The Dunedin Study - DMHDRU


All peer reviewed publications are listed below.

Displaying page 6 of 21.

Thomson, W. M. , Poulton, R., Broadbent, J. M. , Al-Kubaisy, S. | 2006
Xerostomia and medications among 32-year-olds

Acta Odontologica Scandinavica, 2006, 64(64), 249-254.
Our ref: RO510

Show abstract » Objective. To describe the prevalence and associations of xerostomia among adults in their early thirties, with particular attention to medication exposure as a putative risk factor. Material and Methods. The prevalence and associations of xerostomia were investigated among 32-year-old participants in a long-standing prospective cohort study. Some 950 individuals were assessed at ages 26 and 32 years, with medications being recorded on both occasions. Results. The prevalence of xerostomia was 10.0% (with no apparent gender difference), and was significantly higher among those taking antidepressants (odds ratio/4.7), iron supplements (OR/4.1) or narcotic analgesics (OR/2.4). Those taking antidepressants at both ages 26 and 32 years had 22 times the odds of reporting xerostomia. Conclusion. Xerostomia may be a problem for a sizeable minority of young adults.
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Thomson, W. M. , Broadbent, J. M. , Poulton, R., Beck, J.D. | 2006
Changes in periodontal disease experience from age 26 to 32 years of age in abirth cohort

Journal of Periodontology, 2006, 77(77), 947-54.
Our ref: RO509

Show abstract » BACKGROUND: Information is lacking on the natural history of periodontitis through the third and fourth decades of life. METHODS: Periodontal examinations were conducted at 26 and 32 years of age in a longstanding prospective study of a birth cohort born in Dunedin, New Zealand, in 1972 and 1973. At each age, gingival recession (GR) and probing depth (PD) were recorded at three sites per tooth using a diagonal half-mouth design (measurements were made in all four quadrants at 32 years of age, but longitudinal comparisons were made using only the half-mouth data). RESULTS: A total of 882 individuals were examined at both ages. The mean number of measured sites fell between 26 and 32 years of age. The overall prevalence of one or more sites with >or=4 mm combined attachment loss (CAL) rose from 18.6% to 21.8%, whereas there were greater increases in the proportion with two or more sites with >or=4 mm CAL (from 8.0% to 12.6%) and one or more sites with >or=5 mm CAL (from 3.6% to 8.0%). The extent and severity of CAL also increased. A total of 403 individuals (45.7%) had an increase in CAL >or=2 mm at one or more sites, whereas 110 (12.5%) had a CAL increase >or=3 mm at one or more sites. Seen in approximately 4% of sites, negative GR (i.e., gingival enlargement) had a substantial effect on PD-based estimates. An increase in PD >or=2 mm at one or more sites was experienced by 345 individuals (39.1%), whereas 88 people (10.0%) had an increase in PD >or=3 mm at one or more sites. The greatest mean attachment loss was experienced at disto-lingual sites on molars, and most manifested as PD increases. Notable increases in GR were seen with lower incisors and canines. CONCLUSIONS: Periodontal loss of attachment continues among a sizable proportion of people from the third to the fourth decade of life; however, contrary to patterns in older adults, changes in the PD component are greater than the changes in the recession component. Incident attachment loss is most frequently observed at proximal sites on posterior teeth.
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Welch, D. , Dawes, P. J. | 2006
The effects of childhood otitis media on the acoustic reflex threshold at age 15

International Journal of Audiology, 2006, 45(45), 353-9.
Our ref: RO508

Show abstract » Previous research has found that childhood otitis media leads to elevated adulthood acoustic reflex thresholds because of worsened audiometric thresholds in the stimulation ear, and abnormality of the tympanic membrane in the ear from which acoustic reflexes were measured. To confirm and expand this finding, our research utilized longitudinal data from 631 general-population-sampled children assessed between ages 5 and 15. Otitis media was assessed to age 9, audiometric thresholds were measured at age 11, and otoscopy and acoustic reflex thresholds testing were performed at age 15. Our findings support the earlier research, in that acoustic reflex threshold was higher in those with the worst experience of childhood otitis media. However, this was directly mediated not by audiometric threshold in the ear to which the stimulus was delivered, but by the amount of tympanic membrane abnormality in both the stimulus and probe ears. This appeared to have an effect independent of audiometric threshold. Furthermore, only those who suffered the worst, persistent, binaural childhood otitis media showed raised acoustic reflex thresholds.
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Jaffee, S.R., Belsky, J., Harrington, H. L., Caspi, A., Moffitt, T. E. | 2006
When parents have a history of conduct disorder: how is the caregiving environment affected?

Journal of Abnormal Psychology, 2006, 115(115), 309-319.
Our ref: RO507

Show abstract » Individuals with early-emerging conduct problems are likely to become parents who expose their children to considerable adversity. The current study tested the specificity of and alternative explanations for this trajectory. The sample included 246 members of a prospective, 30-year cohort study and their 3-year-old children. Parents who had a history of conduct disorder were specifically at elevated risk for socioeconomic disadvantage and relationship violence, but suboptimal parenting and offspring temperament problems were common to parents with any history of disorder. Recurrent disorder, comorbidity, and adversity in the family of origin did not fully account for these findings. The cumulative consequences of early-onset conduct disorder and assortative mating for antisocial behavior may explain the long-term effects of conduct disorder on young adult functioning.
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Trzesniewski, K. H. , Donnellan, M. B. , Moffitt, T. E. , Robins, R. W. , Poulton, R. , Caspi, A. | 2006
Low self-esteem during adolescence predicts poor health, criminal behavior, and limited economic prospects during adulthood

Developmental Psychology, 2006, 42(42), 381-90.
Our ref: RO506

Show abstract » Using prospective data from the Dunedin Multidisciplinary Health and Development Study birth cohort, the authors found that adolescents with low self-esteem had poorer mental and physical health, worse economic prospects, and higher levels of criminal behavior during adulthood, compared with adolescents with high self-esteem. The long-term consequences of self-esteem could not be explained by adolescent depression, gender, or socioeconomic status. Moreover, the findings held when the outcome variables were assessed using objective measures and informant reports; therefore, the findings cannot be explained by shared method variance in self-report data. The findings suggest that low self-esteem during adolescence predicts negative real-world consequences during adulthood.
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Broadbent, J. M. , Thomson, W. M. , Poulton, R. | 2006
Oral health beliefs in adolescence and oral health in young adulthood

Journal of Dental Research, 2006, 85(85), 339-43.
Our ref: RO505

Show abstract » According to theory, health beliefs are related to health behaviors. We investigated whether individuals who hold favorable oral-health-related beliefs over time have better adult oral health than those who do not. Beliefs about the efficacy of water fluoridation, keeping the mouth clean, avoiding sweet foods, visiting the dentist, using dental floss, and using fluoridated toothpaste were assessed in a birth cohort at ages 15, 18, and 26 years. At each age, the majority of participants endorsed the importance of each practice. However, there was also evidence of instability across time. Individuals who held stable favorable dental beliefs from adolescence through adulthood had fewer teeth missing due to caries, less periodontal disease, better oral hygiene, better self-rated oral health, and more restorations. Dental beliefs can change between adolescence and young adulthood, and these changes are related to oral health. In particular, unfavorable dental health beliefs are related to poorer oral health.
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Ehrensaft, M. K. , Moffitt, T. E. , Caspi, A. | 2006
Is domestic violence followed by an increased risk of psychiatric disorders among women but not among men? A longitudinal cohort study

American Journal of Psychiatry, 2006, 163(163), 885-92.
Our ref: RO504

Show abstract » OBJECTIVE: The association between violence between intimate partners and psychiatric disorders is assumed to reflect a causal link. This assumption is now questioned because several longitudinal studies have documented that adolescents with psychiatric disorders grow up to be overrepresented among adults involved in partner violence. METHOD: The study followed a representative birth cohort prospectively. Adolescent mental disorders were diagnosed at age 18 years. Between ages 24 and 26 years, the authors identified individuals involved in nonabusive relationships versus those involved in clinically abusive relationships (i.e., resulting in injury and/or official intervention). At age 26 years, mental disorders were again diagnosed. RESULTS: Male and female adolescents with psychiatric disorders were at greatest risk of becoming involved in abusive adult relationships. After the authors controlled for earlier psychiatric history, women who were involved in abusive relationships, but not men, had an increased risk of adult psychiatric morbidity. CONCLUSIONS: 1) Psychiatric disorders pose risk for involvement in abusive relationships for both sexes; 2) partner abuse is a contributing source of psychiatric disorders among women but not among men.
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Mill, J. S., Caspi, A. , Williams, B. S. , Craig, I. , Taylor, A. , Polo-Tomas, M. , Berridge, C. W. , Poulton, R. , Moffitt, T. E. | 2006
Prediction of heterogeneity in intelligence and adult prognosis by genetic polymorphisms in the dopamine system among children with attention-deficit/hyperactivity disorder: evidence from 2 birth cohorts

Archives of General Psychiatry, 2006, 63(63), 462-9.
Our ref: RO503

Show abstract » CONTEXT: The study and treatment of psychiatric disorders is made difficult by the fact that patients with identical symptoms often differ markedly in their clinical features and presumably in their etiology. A principal aim of genetic research is to provide new information that can resolve such clinical heterogeneity and that can be incorporated into diagnostic practice. OBJECTIVE: To test the hypothesis that the DRD4 seven-repeat allele and DAT1 ten-repeat allele would prove useful in identifying a subset of children with attention-deficit/hyperactivity disorder (ADHD) who have compromised intellectual functions. DESIGN: Longitudinal epidemiologic investigation of 2 independent birth cohorts. SETTING: Britain and New Zealand. PARTICIPANTS: The first cohort was born in Britain in 1994-1995 and includes 2232 children; the second cohort was born in New Zealand in 1972-1973 and includes 1037 children. MAIN OUTCOME MEASURES: Evaluation of ADHD, IQ, and adult psychosocial adjustment. RESULTS: We present replicated evidence that polymorphisms in the DRD4 and DAT1 genes were associated with variation in intellectual functioning among children diagnosed as having ADHD, apart from severity of their symptoms. We further show longitudinal evidence that these polymorphisms predicted which children with ADHD were at greatest risk for poor adult prognosis. CONCLUSION: The findings indicate that genetic information of this nature may prove useful for etiology-based psychiatric nosologies.
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Fergusson, D.M., Poulton, R., Smith, P.F., Boden, J.M. | 2006
Cannabis and psychosis: a summary and synthesis of the evidence

BMJ, 2006, 332(332), 172-175.
Our ref: RO502

Show abstract » The link between cannabis and psychosis has been extensively investigated in both epidemiological and neuroscientific studies. Epidemiological studies focus on the association between use of cannabis and development of psychosis (box), whereas neuroscientific studies have looked at how cannabis affects neurochemical functioning. However, these two lines of research have been poorly integrated, with little disciplinary cross fertilisation. We have brought together both strands of evidence to give a broader picture.
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McGee, R. , Williams, S.M. , Howden-Chapman, P. , Martin, J. , Kawachi, I. | 2006
Participation in clubs and groups from childhood to adolescence and its effects on attachment and self-esteem

Journal of Adolescence, 2006, 29(29), 1-17.
Our ref: RO501

Show abstract » We examined social participation in organized clubs and groups from childhood to adolescence in a sample of young people from Dunedin, New Zealand. Groups were broadly categorized as sports and cultural/youth groups. While the results indicated high levels of participation in childhood with a decline over the ensuing adolescent years, path analyses suggested strong continuities in participation over time. Both family active-recreational orientation (ARO) and intellectual-cultural orientation (ICO) predicted participation, and mediated the effects of disadvantage on participation. Participation was significantly related to adolescent attachment to parents, friends and school/workplace, as well as self-perceived strengths, after controlling for early family disadvantage and social support, peer attachment and literacy. The effect of participation in adolescence is to widen the social convoy to which young people are exposed as well as strengthening relationships within that convoy.
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Williams, M. J. A., Williams, S. M. , Poulton, R. | 2006
Breast feeding is related to C reactive protein concentration in adult women

Journal of Epidemiology and Community Health, 2006, 60(60), 146-148.
doi: 10.1136/jech.2005.039222
Our ref: RO500

Show abstract » Objective: To assess the influence of infant breast feeding on C reactive protein (CRP), a marker of low grade inflammation associated with cardiovascular mortality independent of serum cholesterol concentrations. Design: Serum CRP, total cholesterol, anthropometric, and blood pressure measurements were performed along with assessment of infant breast feeding duration, birth weight, smoking status, adult socioeconomic status, number of health problems, and hormonal contraceptive use. Setting: A New Zealand predominantly European descent community birth cohort. Participants: 822 men and women aged 26 years. Main results: There was a significant linear relation (p<0.001) between duration of breast feeding and adult CRP level in women. The geometric means (IQR) for CRP were 2.22 (1, 4) mg/l for women breast fed for six months or more and 3.95 (2, 8) mg/l for women not breast fed (ratio, 95% confidence interval (CI): 0.69 (0.55 to 0.87). The linear association between cholesterol and breast feeding was also significant (p = 0.01), the geometric mean (IQR) total cholesterol levels being 4.62 (4.10, 5.10) for those breast fed for six months or more and 5.04 (4.5, 5.80) for those not breast fed (ratio, 95% CI: 0.92 (0.87, 0.98). There was no relation between CRP or total cholesterol and duration of breast feeding in men. Conclusions: The findings of lower CRP with an increased duration of breast feeding in women suggest early postnatal nutrition may influence long term cardiovascular risk.
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Hancox, R. J. , Poulton, R. | 2006
Watching television is associated with childhood obesity - but is it clinically important?

International Journal of Obesity, 2006, 30(30), 171-175.
Our ref: RO490

Show abstract » Objective: To assess the impact of television viewing during childhood and adolescence on body mass index (BMI) in children up to the age of 15 years. Design: Unselected birth cohort, assessed at birth and every 2 years from age 3 to 15 years. Subjects: In all, 1037 individuals were assessed at age 3 years. At age 15 years, 976 (95% of living cohort) continued to participate. Measurements: Parental estimates of weekday television viewing between age 5 and 11 years. Self-reports of television viewing at age 13 and 15 years. Weight and height were measured at each age to calculate BMI. Results: BMI and prevalence of overweight at all ages were significantly associated with mean hours of television viewing reported in the assessments up to that age. These associations were stronger in girls than boys. The associations remained significant after adjusting for parental body mass indices and socio-economic status. Conclusion: Time spent watching television is a significant predictor of BMI and overweight in childhood. Although the effect size appears small, it is larger than the effect sizes commonly reported for nutritional intake and physical activity. Television viewing should be regarded as an important contributing factor to childhood obesity.
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Broadbent, J. M. , Thomson, W. M. | 2005
For debate: problems with the DMF index pertinent to dental caries data analysis

Community Dentistry and Oral Epidemiology, 2005, 33(6), 400-409.
Our ref: RO488.2

Show abstract » Abstract – The Decayed, Missing, Filled (DMF) index has been used for over 50 years and is well established as the key measure of caries experience in dental epidemiology. Despite its long history of use, there is debate about the most appropriate number of surfaces to include for a missing tooth. Assigning the maximum possible value for the ‘M’ component of DMFS (Surfaces) leads to overestimation of an individual's caries experience, and in any associated comparisons of in-caries experience, whereas assigning the minimum possible value for the ‘M’ component has the opposite effect. Alternative methods of assigning the number of caries-affected surfaces for an extracted tooth are considered. The net caries increment and adjusted caries increment (common methods of correction of the crude increment measure for reversals) are discussed, along with incidence density, a measure of caries extent. Problems exist with the adjusted caries increment, particularly among cohorts with low mean baseline caries experience. Development of an alternative method of estimating the relationship of ‘true’ and ‘examiner’ reversals is advocated, as well as greater utilization of incidence density in dental epidemiology.
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Barker, M.J., Thomson, W. M. , Poulton, R. | 2005
Personality traits in adolescence and satisfaction with orthodontic treatment in young adulthood

Australian Orthodontic Journal, 2005, 21(21), 87-93.
Our ref: RO498

Show abstract » Objective: This study aimed to determine whether personality traits are associated with satisfaction with orthodontic treatment by age 26. Methods: A prospective observational cohort study was conducted with 1,037 individuals, one-third of whom had received orthodontic treatment by age 26. A comprehensive personality assessment was conducted at age 18 using the multidimensional personality questionnaire. At age 26, orthodontic outcome was rated as either Excellent, Pretty good, Fair or Poor. Results: Those who were less satisfied (rating their treatment outcome as Fair or Poor) scored lower on the personality traits of control and social closeness, and higher on stress reactivity. Individuals with low scores on social closeness were twice as likely (Odds ratio: 2.07) to be less satisfied with their orthodontic result. Conclusions: Individuals who are impulsive, stress-reactive or socially isolated are more likely to be disappointed with their orthodontic outcome. Pretreatment knowledge about certain aspects of personality might be useful to practising orthodontists.
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Andrews, G., Poulton, R., Skoog, I. | 2005
Lifetime risk of depression: restricted to a minority or waiting for most? Editorial

British Journal of Psychiatry, 2005, 187(187), 495-496.
Our ref: RO497

Show abstract » Depression remits and recurs, but among what proportion of the population? Retrospective surveys report the lifetime risk to be around 10%. A modelling study and two prospective studies concur that close to half the population can expect one or more episodes of depression in their lifetime.
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Piquero, A.R., Brame, B., Moffitt, T.E. | 2005
Extending the study of continuity and change: gender differences in the linkage between adolescent and adult offending

Journal of Quantitative Criminology, 2005, 21(21), 219-243.
Our ref: RO496

Show abstract » Recently, Paternoster et al. used data from the Cambridge Study in Delinquent Development, a longitudinal study of 411 South London boys mostly born in 1953, to investigate the linkage between adolescent and adult offending and found that variations in adult offending were consistent with a random process after conditioning on adolescent offending. In this paper, we test the robustness of this early study across data sources and genders. Here, we use data from the Dunedin New Zealand 1972 birth cohort study to replicate previous findings regarding stability and change in criminal offending between the adolescent and adult years. In particular, our interest centers on the stochastic properties of the adolescent and adult conviction distribution in the cohort and whether the structure of this distribution is similar for males and females. This replication and extension of prior work is especially important since criminologists have little understanding of the pattern of female adolescent offending or how the patterns are linked to adult offending for women. The analysis reveals that variation in adult offending after conditioning on adolescent offending is consistent with a random (Poisson) process. Furthermore, this pattern is evident for both the males and the females in the Dunedin New Zealand 1972 birth cohort.
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Mandhane, P. J. , Greene, J. M. , Cowan, J. O. , Taylor, D. R. , Sears, M. R. | 2005
Sex differences in factors associated with childhood- and adolescent-onset wheeze

American Journal of Respiratory and Critical Care Medicine, 2005, 172(172), 45-54.
Our ref: RO495

Show abstract » RATIONALE: Factors predicting the development of wheeze may differ between sexes and between childhood and adolescence. METHODS: A New Zealand birth cohort of 1,037 children was followed to age 26. For this analysis, those reporting recurrent wheezing at two or more assessments were classified as wheezers. We examined risk factors for development of wheeze before age 10 (childhood) and subsequently (adolescent-onset) for males and for females separately using Cox regression modeling. RESULTS: Males more often developed childhood wheeze (p = 0.002) and females adolescent-onset wheeze (p < 0.001). Maternal atopy (asthma or hay fever) was a risk factor for childhood wheeze in both sexes (hazard ratio [HR], 1.48, p < 0.05 for males; HR, 2.37, p < 0.001 for females). Paternal atopy also influenced childhood wheeze, significantly for males (HR, 1.72; p = 0.01), and similarly but not significantly for females (HR, 1.70; p = 0.08). For adolescent-onset wheeze, neither maternal (HR, 1.41; p = 0.19) nor paternal history (HR, 0.73; p = 0.42) was a risk factor in males, but maternal history (HR, 2.08; p < 0.01) was a significant risk factor for females. When both age ranges were combined, providing greater power for analysis, paternal history was a stronger risk factor for wheeze in females (HR, 1.62; p = 0.02) than in males (HR, 1.35; p = 0.12). CONCLUSION: The influence of parental atopy on the development for wheeze differs between males and females and between childhood- and adolescent-onset wheeze.
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Silver, E., Arseneault, L., Langley, J.D., Caspi, A., Moffitt, T.E. | 2005
Mental disorder and violent victimisation in a total birth cohort

American Journal of Public Health, 2005, 95(95), 2015-2021.
Our ref: RO494

Show abstract » We examined the association between mental disorder and violent victimization in a general population sample. We performed a multivariate analysis of violent victimization in a 12-month period on a total birth cohort with follow-up data that assessed, during their 21st year, males and females born in Dunedin, New Zealand, in the early 1970s. Compared with people with no mental disorder, (1) people with anxiety disorders experienced more sexual assaults, (2) people with schizophreniform disorders experienced more threatened and completed physical assaults, (3) people with alcohol dependence disorders experienced more completed physical assaults, and (4) people with marijuana dependence disorders experienced more attempted physical assaults. These results held after control for psychiatric comorbidity, demographic characteristics, and the study participants' own violent behavior. Mentally disordered young adults tend to experience more violent victimization in the community than those without a mental disorder.
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Gulliver, P. , Begg, D. J. | 2005
Usual water-related behaviour and 'near-drowning' incidents in young adults

Australian and New Zealand Journal of Public Health, 2005, 29(29), 238-243.
Our ref: RO493

Show abstract » OBJECTIVE: To describe usual water-related behaviour and 'near-drowning' incidents in a cohort of young New Zealand adults. METHOD: This was a cross-sectional study based on data collected as part of the Dunedin Multidisciplinary Health and Development Study, which is the study of a cohort (n = 1,037) born between 1 April 1972 and 31 March 1973 in Dunedin, New Zealand. The data analysed were collected at age 21 (1993/94). Each study member was given a face-to-face interview using a structured questionnaire. RESULTS: Males reported a higher level of water confidence, exposure to risk behaviours, and exposure to unsafe locations, and more 'near-drowning' incidents, than the females, but protective behaviour did not differ. Males and females who were 'confident' in the water were more likely to be exposed to unsafe water locations, and water-confident males were more likely to drink alcohol before water activities, but not boating. A total of 169 'near-drowning' incidents were reported by 141 study members (63% males). 'Near-drowning' incidents were associated with unsafe swimming environments for males (p < 0.001) and boating within two hours of consuming alcohol for females (p = 0.002). CONCLUSIONS: This study described usual water-related behaviour and has provided preliminary evidence of the factors associated with 'near-drowning' incidents among a high-risk age group. Larger case-control studies are required to further investigate risk factors for 'near-drowning'. IMPLICATIONS FOR PRACTITIONERS: Further investigation is required to determine the effectiveness of providing water skills acquisition in both safe and unsafe environments on 'near-drowning' experience.
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Howell, S., Poulton, R., Talley, N. J. | 2005
The natural history of childhood abdominal pain and its association with adult irritable bowel syndrome: birth cohort

American Journal of Gastroenterology, 2005, 100(100), 2071-2078.
Our ref: RO491

Show abstract » NTRODUCTION: The natural history of childhood abdominal pain (CAP) and its association with adult irritable bowel syndrome (IBS) remain poorly described. We aim to investigate the characteristics of CAP over the first 11 yr of life and evaluate the association of CAP to IBS at age 26 yr. METHOD: The data were collected from a 1972 birth cohort (Dunedin, NZ) who were re-assessed at ages 3, 5, 7, 9, 11, 13, 15, 18, 21, and 26 yr. IBS was classified according to Manning Criteria, as assessed using symptom data collected at age 26 yr. A history of CAP was established by scrutinizing data for all assessments completed from birth to age 11 yr. Three measures were described: medical service encounters for CAP, parental (mainly maternal) report of stomach pain (frequency over the past year), and a composite measure which included both medical encounters and parent report: three childhood time frames were evaluated-ages 0-7, 7-9, and 9-11 yr. RESULTS: A history of CAP was reported by 18.1% of children. This was typically characterized by CAP on one assessment; complaints over two or more assessment were rare. CAP was slightly more common in females and appeared to peak at age 7-9 yr. IBS at age 26 yr was significantly more common among individuals with a history of CAP between ages 7 and 9 yr compared to those with no such history, as assessed by any history (OR = 1.85; p= 0.02), parental report (OR = 1.82; p= 0.03), and medical service encounters (OR = 3.75; p= 0.03). The association between CAP at age 7-9 yr and adult IBS was not altered by adjustment for sex, socio-economic status, psychiatric disorder at age 26 yr, childhood emotional distress, or mother's score on the Malaise Inventory. CONCLUSIONS: CAP is a common complaint, which can progress to adult IBS in some children.
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Dickson, N., van Roode, T., Paul, C. | 2005
Herpes simplex virus type-2 status at age 26 is not related to early circumcision in a birth cohort

Sexually Transmitted Diseases, 2005, 32(32), 517-519.
Our ref: RO489

Show abstract » Objectives: To determine if circumcision in early childhood affects the risk of acquiring herpes simplex virus type-2 (HSV-2) infection. Study Design: Study members were born in 1972/73 in Dunedin, New Zealand. Circumcision status was sought at age 3, when the cohort was established. Information about sexual behaviour was obtained at ages 21 and 26. Serum was tested for HSV-2 antibodies at age 26 for 435 men (82.9% of the surviving cohort). Results: Of eligible men, 40.2% had been circumcised. The prevalence of HSV-2 antibodies was 7.3% in uncircumcised men and 7.4% in circumcised men. Social and sexual factors were very similar between the two groups and adjustment had no effect on the association (odds ratio=1.1, 95% CI 0.46-2.5). Seroconversion rates according to years since first sexual intercourse were 0.85 and 0.86 per 100 person-years for uncircumcised and circumcised men. Conclusion: The results support a lack of association between circumcision status and HSV-2 acquisition, although a small effect cannot be ruled out.
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Broadbent, J. M. , Thomson, W. M. , Williams, S. M. | 2005
Does caries in primary teeth predict enamel defects in permanent teeth? A longitudinal study

Journal of Dental Research, 2005, 84(84), 260-4.
Our ref: RO488

Show abstract » The notion that caries in primary teeth causes developmental defects of enamel in permanent teeth has been recently revived. The research objective was to test this hypothesis through analysis of data from the Dunedin Multidisciplinary Health and Development Study, a longstanding prospective cohort study. The maxillary incisors of 663 children were assessed for existing restorations and dental caries at age five and for developmental defects of enamel at age nine. Where a primary tooth had been carious, the permanent successor was more likely to have a demarcated opacity after adjustment for gender, family socio-economic status, years of exposure to water fluoridation, trauma to primary teeth, and early loss of primary teeth (unadjusted OR = 2.3, 95% CI 1.3, 4.1; adjusted OR = 2.2, 95% CI 1.1, 4.3). These findings support a time-ordered association between dental caries in primary maxillary incisors and demarcated opacities in their permanent successors.
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Williams, S. M. | 2005
Weight and height growth rate and the timing of adiposity rebound

Obesity Research, 2005, 13(13), 1123-1130.
Our ref: RO487

Show abstract » OBJECTIVE: Adiposity rebound occurs when the ratio of the velocities of log(weight) to log(height) changes from <2 to >2. This study examined the timing of adiposity rebound in the context of the velocities of weight and height in early childhood because it is not known whether faster weight gain or slower gain in stature is the more important determinant. RESEARCH METHODS AND PROCEDURES: This was a longitudinal study of 406 boys and 397 girls born in Dunedin, New Zealand, in 1972 and 1973. Each child's height and weight were measured at 3 years of age and at least twice more as part of their two yearly assessments until 11 years of age. RESULTS: The mean age of adiposity rebound was 6.6 +1.10 years (SD) for boys and 6.0 + 1.21 years for girls. After adjusting for sex, the correlations between the timing of rebound and z-scores for BMI, weight, and height at rebound were -0.35, -0.30, and -0.14, respectively. Correlations between the timing of rebound and estimated values of weight and height velocities at 3 years were -0.48 and -0.00. The correlations with BMI and waist girth at 26 years were -0.39 and -0.35. DISCUSSION: Children with an earlier adiposity rebound were heavier and had above average BMIs. Early rebound is the result of higher rates of weight gain, measured in percentage terms, rather than slower than average accrual of stature. This suggests that restraining weight gain could delay adiposity rebound and prevent obesity in early adulthood.
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Slutske, W., Caspi, A., Poulton, R., Moffitt, T. E. | 2005
Personality and problem gambling: a prospective study of a birth cohort of young adults

Archives of General Psychiatry, 2005, 62(62), 769-775.
Our ref: RO486

Show abstract » Context Individual differences in dimensions of personality may play an important role in explaining risk for disordered gambling behavior as well as the comorbidity between disordered gambling behavior and other substance-related addictive disorders. Objectives To identify the personality correlates of problem gambling in a representative nontreatment-seeking sample, as well as to determine whether these are similar to the personality correlates of other substance-related addictive disorders and whether individual differences in personality might account for the comorbidity between disordered gambling behavior and other substance-related addictive disorders. Design Longitudinal population-based study. Participants A complete birth cohort of young adults born in Dunedin, New Zealand, between April 1, 1972, and March 31, 1973 (N=939; 475 men, 464 women). Main Outcome Measures Multidimensional Personality Questionnaire assessments of personality were obtained at age 18 years; structured interview-based diagnoses of past-year problem gambling and alcohol, cannabis, and nicotine dependence were obtained at age 21 years. Results Problem gambling at age 21 years was associated with higher scores on the higher-order personality dimension of negative emotionality (d=0.90) and with lower scores on the personality dimension of constraint (d=0.72) measured at age 18 years compared with control subjects who did not have a past-year addictive disorder at age 21 years. Problem gambling was also associated with Multidimensional Personality Questionnaire indicators of risk-taking (d=0.50) and impulsivity (d=0.56). The personality profile associated with problem gambling was similar to the profiles associated with alcohol, cannabis, and nicotine dependence. The relations between problem gambling and the substance-related addictive disorders (odds ratios=3.32-3.61) were reduced after controlling for individual differences in personality (odds ratios=1.90-2.32). Conclusions From the perspective of personality, problem gambling has much in common with the addictive disorders, as well as with the larger class of externalizing or disinhibitory disorders. Knowledge gained from the study of common personality underpinnings may be helpful in determining where disordered gambling behavior should reside in our diagnostic classification system.
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Hancox, R. J. , Milne, B.J., Poulton, R. | 2005
Association of television viewing during childhood with poor educational achievement

Archives of Pediatrics & Adolescent Medicine, 2005, 159(159), 614-618.
Our ref: RO485

Show abstract » Background: Excessive television viewing in childhood has been associated with adverse effects on health and behavior. A common concern is that watching too much television may also have a negative impact on education. However, no long-term studies have measured childhood viewing and educational achievement. Objective: To explore these associations in a birth cohort followed up to adulthood. Design: Prospective birth cohort study. Setting: Dunedin, New Zealand. Participants: Approximately 1000 unselected individuals born between April 1, 1972, and March 31, 1973. Ninety-six percent of the living cohort participated at 26 years of age. Main Outcome Measures: Educational achievement by 26 years of age. Results: The mean time spent watching television during childhood and adolescence was significantly associated with leaving school without qualifications and negatively associated with attaining a university degree. Risk ratios for each hour of television viewing per weeknight, adjusted for IQ and sex, were 1.43 (95% confidence interval [CI], 1.24-1.65) and 0.75 (95% CI, 0.67- 0.85), respectively (both, P<.001). The findings were similar in men and women and persisted after further adjustment for socioeconomic status and early childhood behavioral problems. Television viewing during childhood (ages 5-11 years) and adolescence (ages 13 and 15 years) had adverse associations with later educational achievement. However, adolescent viewing was a stronger predictor of leaving school without qualifications, whereas childhood viewing was a stronger predictor of non-attainment of a university degree. Conclusions: Television viewing in childhood and adolescence is associated with poor educational achievement by 26 years of age. Excessive television viewing in childhood may have long-lasting adverse consequences for educational achievement and subsequent socioeconomic status and well-being.
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Fawcett, J. P. , Barbezat, G. O. , Poulton, R. , Milne, B. J. , Xia, H. H. , Talley, N. J. | 2005
Helicobacter pylori serology in a birth cohort of New Zealanders from age 11 to 26

World Journal of Gastroenterology, 2005, 11(11), 3273-3276.
Our ref: RO484

Show abstract » AIM: To determine seroprevalence of Helicobacter pylori (H pylori) in the Dunedin Multidisciplinary Health and Development Study (DMHDS) at age 26 in order to investigate seroconversion and seroreversion from age 11 to 26 and the association of seropositivity with risk factors for H pylori infection. METHODS: Participants in the DMHDS at age 26 and retrospectively at age 21 were tested for H pylori antibodies using two commercially available ELISA kits. Gender, socioeconomic status (SES), smoking, educational attainment and employment at age 26 were tested for association with H pylori seropositivity. RESULTS: At ages 21 and 26, seroprevalence of H pylori using one or other kit was 4.2% (n = 795) and 6.3% (n = 871) respectively. Seroreversion rate was lower than seroconversion rate (0.11% vs 0.53% per person-year) in contrast to the period from age 11 to 21 when seroreversion rate exceeded seroconversion rate (0.35% vs 0.11% per person-year). Serology in those tested at ages 11, 21, and 26 remained unchanged in 93.6% of the sample. Seroprevalence at age 26 was lower among those with a secondary school qualification (P = 0.042) but was not associated with gender, SES, smoking or employment status. CONCLUSION: H pylori seroprevalence in a New Zealand birth cohort remains low between ages 11 and 26. H pylori infection remains stable from childhood to adulthood although seroreversion seems to be more common in the adolescent years than in young adults.
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Williams, M. J. A., Milne, B. J. , Hancox, R. J. , Poulton, R. | 2005
C-reactive protein and cardiorespiratory fitness in young adults

European Journal of Cardiovascular Prevention and Rehabilitation, 2005, 12(12), 216-20.
Our ref: RO483

Show abstract » BACKGROUND: Fitness and obesity are both independently associated with cardiovascular events and mortality. C-reactive protein (CRP), a predictor of cardiovascular events is associated with obesity; but its association with cardiorespiratory fitness in early adulthood is uncertain. The aim of this study was to examine the relationship between cardiorespiratory fitness and CRP, controlling for obesity in an unselected cohort of young adults. DESIGN: A cross-sectional study in a representative birth cohort. METHODS: We measured CRP levels, cardiorespiratory fitness, anthropometric variables, blood pressure and smoking in 26-year-old men (n=400) and women (n=315). Log CRP levels were compared across cardiorespiratory fitness with adjustment for body mass index (BMI), sex, blood pressure, smoking and combined oral contraceptive use. RESULTS: Geometric mean CRP levels were higher in women (3.23 mg/l, 95% CI 2.85-3.64) compared with men (1.70 mg/l, 1.52-1.89). Regression analysis adjusting for sex and weight showed an inverse association between fitness and CRP (beta=-0.16, P<0.001). This association held after statistical controls were added for BMI, systolic blood pressure and smoking and combined oral contraceptive use (P
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Stanton, W. R. , Barnett, A. G. , Silva, P. A. | 2005
Adolescents' intentions to smoke as a predictor of smoking

Preventive Medicine, 2005, 40(40), 221-226.
Our ref: RO482

Show abstract » BACKGROUND: Adolescents' intentions to smoke are generally regarded as a valid and reliable predictor of subsequent smoking. This association is largely based on research with adults and needs a more detailed analysis for adolescents. METHODS: Data on intentions and smoking status were collected as part of a longitudinal, birth-cohort study when the study members were 9, 11, 13, 15, 18, and 21 years of age. RESULTS: The results showed that intention to smoke only had an important predictive power in the subgroup of previous nonsmokers. Among those already smoking (on a monthly basis or greater), previous level of smoking was a more important predictor of future behavior than intention to smoke. In addition, the effect of positive intention to smoke was nonlinear over age and had the greatest effect at age 15. CONCLUSION: The results indicated that in adolescence, measurement of intentions to smoke or not smoke cannot be assumed to be a general predictor of behavior at a later age for all groups of adolescents.
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Taylor, D.R. , Cowan, J.O., Greene, J.M., Willan, A., Sears, M.R. | 2005
Asthma in remission: can relapse in early adulthood be predicted at age 18 years of age

Chest, 2005, 127(127), 845-850.
Our ref: RO481

Show abstract » Study Objective: To determine the frequency of relapse of asthma in young adults in remission at age 18, during a follow-up period of 8 years, and to identify possible prognostic markers for relapse. Design: Longitudinal study of birth cohort (n=1037) born in New Zealand in 1972/3. Setting: University Hospital research clinic. Measurements: Participants were assessed at age 9, 11, 13, 15, 18, 21 and 26 using a respiratory questionnaire (all ages), spirometry (all ages), bronchodilator response (ages 18 and 26), methacholine challenge (ages 9, 11, 13, 15 and 21) and allergen skin prick testing (ages 13 and 21). Results: Approximately one third (35%) of study members whose asthma was in remission at age 18 experienced relapse by age 21 or 26. Atopy and lower FEV1/VC ratio at age 18 were significant independent prognostic factors for relapse in multiple logistic regression analyses. Increased responsiveness to methacholine (PC20 less than 8mg/ml) or bronchodilator (improvement in FEV1 of 10% or greater) at age 21 were more common among those who relapsed, but the positive and negative predictive values for a previous positive methacholine challenge test at age 15 were low. Asthma after relapse was generally mild (mean FEV1 97.1% predicted). Totally new adult asthma developed by age 26 in 9% of study members who had no asthma or wheezing at any time up to age 18. Conclusions: Subsequent relapse of previously diagnosed asthma which is in remission at age 18 occurs in one in three young adults. Such relapse is not easily predicted, especially by measurements of airway responsiveness. A history of asthma currently in remission should not be used to prejudice employment opportunities for young adults.
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Donnellan, M. B., Trzesniewski, K. H., Robins, R. W., Moffitt, T. E., Caspi, A. | 2005
Low self-esteem is related to aggression, antisocial behavior, and delinquency

Psychological Science, 2005, 16(16), 328-35.
Our ref: RO480

Show abstract » The present research explored the controversial link between global self-esteem and externalizing problems such as aggression, antisocial behavior, and delinquency. In three studies, we found a robust relation between low self-esteem and externalizing problems. This relation held for measures of self-esteem and externalizing problems based on self-report, teachers' ratings, and parents' ratings, and for participants from different nationalities (United States and New Zealand) and age groups (adolescents and college students). Moreover, this relation held both cross-sectionally and longitudinally and after controlling for potential confounding variables such as supportive parenting, parent-child and peer relationships, achievement-test scores, socioeconomic status, and IQ. In addition, the effect of self-esteem on aggression was independent of narcissism, an important finding given recent claims that individuals who are narcissistic, not low in self-esteem, are aggressive. Discussion focuses on clarifying the relations among self-esteem, narcissism, and externalizing problems.
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Gregory, A.M., Caspi, A., Eley, T.C., Moffitt, T. E. , O'Connor, T.G., Poulton, R. | 2005
Prospective longitudinal associations between persistent sleep problems in childhood and anxiety and depression disorders in adulthood

Journal of Abnormal Child Psychology, 2005, 33(33), 157-163.
Our ref: RO479

Show abstract » The objective of this study was to examine the associations between persistent childhood sleep problems and adulthood anxiety and depression. Parents of 943 children (52% male) participating in the Dunedin Multidisciplinary Health and Development Study provided information on their children's sleep and internalizing problems at ages 5, 7, and 9 years. When the participants were 21 and 26 years, adult anxiety and depression were diagnosed using a standardized diagnostic interview. After controlling for childhood internalizing problems, sex, and socioeconomic status, persistent sleep problems in childhood predicted adulthood anxiety disorders (OR (95% CI) = 1.60 (1.05-2.45), p = .030) but not depressive disorders (OR (95% CI) = .99 (.63-1.56), p = .959). Persistent sleep problems in childhood may be an early risk indicator of anxiety in adulthood.
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Caspi, A., Moffitt, T.E., Cannon, M., McClay, J., Murray, R. M., Harrington, H. L., Taylor, A., Arseneault, L., Williams, B.S., Braithwaite, A., Poulton, R., Craig, I. | 2005
Moderation of the effect of adolescent-onset cannabis use on adult psychosis by a functional polymorphism in the COMT gene: Longitudinal evidence of a gene x environment interaction

Biological Psychiatry, 2005, 57(57), 1117-1127.
Our ref: RO478

Show abstract » Background: Recent evidence documents that cannabis use by young people is a modest statistical risk factor for psychotic symptoms in adulthood, such as hallucinations and delusions, as well as clinically significant schizophrenia. The vast majority of cannabis users do not develop psychosis, however, prompting us to hypothesize that some people are genetically vulnerable to the deleterious effects of cannabis. Methods: In a longitudinal study of a representative birth cohort followed to adulthood, we tested why cannabis use is associated with the emergence of psychosis in a minority of users, but not in others. Results: A functional polymorphism in the catechol-O-methyltransferase (COMT) gene moderated the influence of adolescent cannabis use on developing adult psychosis. Carriers of the COMT valine allele were most likely to exhibit psychotic symptoms and to develop schizophreniform disorder if they used cannabis. Cannabis use had no such adverse influence on individuals with two copies of the methionine allele. Conclusions: These findings provide evidence of a gene environment interaction and suggest that a role of some susceptibility genes is to influence vulnerability to environmental pathogens.
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Belsky, J., Jaffee, S.R., Sligo, J., Woodward, L., Silva, P.A. | 2005
Intergenerational transmission of warm-sensitive-stimulating parenting: A prospective study of mothers and fathers of 3-year-olds

Child Development, 2005, 76(76), 384-396.
Our ref: RO477

Show abstract » More than 200 New Zealand men and women studied repeatedly since age 3 were videotaped interacting with their own 3-year-old children to determine (a) whether childrearing and family climate experienced in 3 distinct developmental periods while growing up (i.e., early childhood, middle childhood, early adolescence) predicted parenting and (b) whether romantic relationship quality moderated the effect of childrearing history on observed parenting. Support for the first hypothesis emerged across all 3 developmental periods for mothers (only), with no evidence of moderating effects of romantic relationship quality for mothers or fathers. Results are discussed in terms of supportive versus harsh parenting, motherfather differences, and the characteristics of the sample.
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Poulton, R. , Caspi, A. | 2005
Commentary: How does socioeconomic disadvantage during childhood damage health in adulthood? Testing psychosocial pathways

International Journal of Epidemiology, 2005, 34(34), 344-345.
ISSN 0300-5771
Our ref: RO476

Show abstract » Commentary in Special Theme Section on Socioeconomic Position and Health
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McGee, R., Williams, S.M., Nada-Raja, S. | 2005
Is cigarette smoking associated with suicidal ideation among young people?

American Journal of Psychiatry, 2005, 162(162), 619-620.
Our ref: RO475

Show abstract » OBJECTIVE The authors examined the association between suicidal ideation in early adulthood and daily tobacco smoking in a community sample of adolescents. METHOD Participants were enrolled in a longitudinal study of health and development. The factors of disadvantage, impulsiveness, stress, depressed mood, tobacco smoking, other substance use, and parental attachment were included in multivariate modelling of suicidal ideation. RESULTSData on tobacco use were available for 764 participants. Early tobacco smoking was significantly predictive of later suicidal ideation, but there was no longer a significant relationship when high levels of stress and depression and low levels of parental attachment in adolescence were included in the multivariate model. CONCLUSIONS Tobacco smoking in adolescence does not appear to elevate the risk of later suicidal ideation
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Goulding, A., Jones, I.E., Williams, S.M., Grant, A.M., Taylor, R.W., Manning, P.J., Langley, J.D. | 2005
First fracture increases risk of new fractures during growth

Journal of Pediatrics, 2005, 146(146), 286-288.
Our ref: RO474

Show abstract » Prior fracture was associated with increased risk of new fracture in 601 members of a cohort studied between birth and l8 years. Hazard ratios for new fracture in data adjusted for age and sex were l.90 (95%CI l.51-2.39) after first fracture and 3.04 (95% CI 2.23-4.15) after second fracture.
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Hancox, R. J. , Milne, B. J. , Poulton, R. , Taylor, D. R. , Greene, J. M. , McLachlan, C. R. , Cowan, J. O. , Flannery, E. M. , Herbison, G. P. , Sears, M. R. | 2005
Sex Differences in the relation between Body Mass Index and asthma and atopy in a Birth Cohort

American Journal of Respiratory and Critical Care Medicine, 2005, 171(171), 440-445.
Our ref: RO473

Show abstract » Rationale: Several studies have identified an association between asthma and obesity in women. It remains unclear if this association is due to genuine asthma or to symptoms caused by overweight, at what age the association develops, and whether it is confined to females. Objective: To explore the relations between body mass index, asthma, and atopy in a birth cohort of approximately 1,000 individuals. Methods: Information on asthma and measurements of lung function, airway responsiveness, and atopy were obtained on multiple occasions between ages 9 and 26. Associations between these outcomes and body mass index were analyzed using generalized mixed linear regression models. Further analyses adjusted for potential covariates including breastfeeding, birth order, parental asthma, and personal and family smoking history. Main results: Body mass index was positively associated with asthma, wheeze, asthma treatment, atopy, immunoglobulin E, and inversely with the FEV1/ FVC ratio in females. There was no significant association with airway responsiveness to methacholine or salbutamol. There was little evidence of an association between body mass index and asthma or atopy in males. Analyses adjusting for potential covariates showed similar findings. Asthma was not associated with a raised body mass index in childhood and childhood asthma did not lead to being overweight as an adult. Conclusions: A raised body mass index is associated with asthma and atopy in women but not men. Population attributable fraction calculations estimate that28%(95% confidence interval 745) of asthma developing in women after age 9 is due to overweight.
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McBride, D.L., Begg, D.J., Herbison, G.P., Buckingham, K. | 2004
Low back pain in young New Zealanders

New Zealand Medical Journal, 2004, 117(117), U1099.
Our ref: NZ88

Show abstract » AIMS: To describe the occupational implications and impact of low back pain (LBP) in a birth cohort now aged 26. METHODS: The LBP data were collected by an interviewer-administered questionnaire. Study members were asked about the prevalence and frequency of LBP and, for the worst episode, details were sought on occupation, time off work or job limitation, the severity of the discomfort, and disability. RESULTS: The cohort comprised 980 individuals, and 969 individuals answered the questionnaire. Of these 969 individuals, 524 (54%) experienced LBP in the previous 12 months, with a modal frequency of three or more times a year. For the 448 individuals with a current occupation, there was no difference in the distribution of LBP between those with professional, clerical, and technical jobs and those with production or trades jobs. Fifty-six individuals had to have time off work (the majority for less than 7 days), and 13 individuals could not look after themselves because of pain. Based on data gathered on 26 year olds, the cost to the economy is estimated as NZ500 million dollars per annum. CONCLUSION: LBP is prevalent and disabling even in young people, and has high costs. The natural history of the disorder is still largely unknown, but work does play a part. Although getting a person back to work may still be the best treatment, it is important to address the workplace factors.
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Keller-Olaman, S., Williams, S.M., Knight, R.G., McGee, R. | 2004
The self-rated health of women in mid-life: a cross-sectional and longitudinal study of a New Zealand sample

New Zealand Journal of Psychology, 2004, 33(33), 66-77.
Our ref: NZ87

Show abstract » Correlates of self-rated health were examined among 704 New Zealand women in mid-life. Logistic regression was used and the variables were grouped within six domains: Health status variables, socio-demographics, social integration, health-influencing behaviours, preventive behaviours, and service utilisation. The final models were dominated by the health status variables. When health status was excluded, poor self-rated health was predicted by not having paid work, low satisfaction with social support, and use of hospital services. A low level of physical activity, being overweight, and two or more visits to a health professional in the past 12 months were associated with good rather than very good self-rated health. The models validated the use of self-rated health as an indicator of health status. The findings also identified the importance of social circumstances when interpreting poor health and lifestyle factors when interpreting good health.
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Stanton, W.R., Flay, B.R., Colder, C.R., Mehta, P. | 2004
Identifying and predicting adolescent smokers' developmental trajectories

Nicotine & Tobacco Research, 2004, 6(6), 843-852.
Our ref: RO499

Show abstract » Very few studies have defined trajectories of smoking. In the present study, we modeled growth in adolescent smoking and empirically identified prototypical trajectories. We conceptualized escalation of smoking as a growth process and modeled rates of change and heterogeneity of these patterns using latent growth mixture modeling. The analysis identified six trajectories with low ambiguity about group membership (early rapid escalators, late rapid escalators, late moderate escalators, late slow escalatorssmokers, stable puffers, and late slow escalatorspuffers). A trajectory of quitters was not identified. We also examined predictors of the smoking trajectories. The predictors were assessed across the adolescent years and included variables related to smoking and other substance use, as well as a range of variables related to sociodemographic factors and mental health. Observed change in the pattern of predictors across age has implications for the mechanism of effect of these variables in relation to smoking trajectories, including predictors that differentiated among daily smokers, variables that may determine the trajectory (e.g., friends smoking), and variables that may result from the trajectory (e.g., marijuana use, less attachment to friends).
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