Did Finland's Tobacco Control Act of 1976 have an impact on ever smoking? An examination based on male and female cohort trends.
(17/105)
OBJECTIVE: To examine patterns of ever smoking among Finnish adults by gender and birth cohort from 1978 to 2001, with special emphasis on the possible effects of the 1976 Tobacco Control Act (TCA). METHODS: The data were derived from independent, annual cross sectional postal surveys among 15-64 year olds (n = 91,342), average response rate 75%. For the analyses 13 five year birth cohorts from 1916 to 1980 were constructed. Birth cohort variations in ever regular smoking were first examined graphically, and then logistic models were used to test the impact of the TCA. RESULTS: Among men there was a decrease in smoking from older to younger cohorts. For women an increase in smoking was observed between successive cohorts. A clear decline in the prevalence of ever smokers concurrent with the TCA was found among both men and women. CONCLUSIONS: The smoking behaviour trends across successive birth cohorts suggest the impact of tobacco policy in decreasing smoking initiation in youth. These findings thus support the acceptability and effectiveness of antismoking and smoke free policy measures in society. (+info)
Longitudinal patterns and predictors of alcohol consumption in the United States.
(18/105)
OBJECTIVES: We examined demographic predictors of longitudinal patterns in alcohol consumption. METHODS: We used mixed-effects models to describe individual alcohol consumption and change in consumption with age, as well as the associations between consumption and birth year, national alcohol consumption, and demographic factors, among 14 105 adults from the National Health and Nutrition Examination Survey I Epidemiologic Follow-Up Study. RESULTS: Alcohol consumption declined with increasing age, and individual consumption mirrored national consumption. Higher consumption was associated with male gender, being White, being married, having a higher educational level, having a higher income, being employed, and being a smoker. Faster age-related decline in consumption was associated with earlier cohorts, being male, being married, having a lower educational level, and being a smoker. CONCLUSIONS: Compared with alcohol consumption among earlier cohorts, that among recent cohorts declined more slowly with increasing age, suggesting that negative health effects of alcohol could increase in the future. (+info)
Heritability of schizophrenia and major affective disorder as a function of age, in the presence of strong cohort effects.
(19/105)
It remains unclear whether age at onset for major psychiatric disorders is a useful marker of etiologic and genetic heterogeneity. The authors examined how heritability of schizophrenia and major affective disorders varied with age at onset. The sample was drawn from a large archival data set collected by Lionel Penrose, comprising 3,109 families with two or more members first hospitalized in Ontario between 1874 and 1944. The authors studied 1,295 sibships with schizophrenia (n = 487), major affective disorder (n = 378), both (n = 234) or neither (n = 196) of these disorders. Proportional hazards models were used to estimate how the hazard of hospitalization for each disorder (schizophrenia or major affective disorder) varied with proband age at onset, adjusted for changes in age at onset distribution between 1874 and 1944. A sibling's risk of hospitalization for the same illness significantly increased for each 10-year decrease in age at onset of the proband both for schizophrenia (hazard ratio = 1.21, 95 % confidence interval: 1.06, 1.39), and for affective disorder (hazard ratio = 1.29,95 % CI: 1.14, 1.45). Gender of proband was unrelated to sibling risk of the same illness, and tests of interaction effects between proband age at onset and gender on sibling risk were nonsignificant. (+info)
Child mortality and cohort lifespan: a test of diminished entelechy.
(20/105)
BACKGROUND: The literature implies a 'diminished entelechy' hypothesis in which birth cohorts subjected to relatively many or relatively virulent environmental insults early in life do not realize their otherwise expected lifespan. No direct test of this hypothesis appears in literature. METHODS: We test the hypothesis directly by measuring the association between mortality in the first 5 years and life expectancy at age 5 for male and female cohorts born in Sweden (1751-1912), Denmark (1835-1913), and England and Wales (1841-1912). The methods control for trends, seasonal cycles, and other forms of autocorrelation that could induce spurious associations. RESULTS: Our results support the hypothesis in that life expectancy at age 5 fell below the values expected from history in cohorts in which child mortality before age 5 increased over its expected value. We find no evidence for culling effects in which a cohort remaining after suffering relatively many environmental insults may be smaller but hardier than expected. CONCLUSIONS: These findings converge with individual-level studies and suggest that suffering relatively virulent or many environmental insults during childhood reduces the subsequent lifespan of birth cohorts. (+info)
Influence of mom and dad: quantitative genetic models for maternal effects and genomic imprinting.
(21/105)
The expression of an imprinted gene is dependent on the sex of the parent it was inherited from, and as a result reciprocal heterozygotes may display different phenotypes. In contrast, maternal genetic terms arise when the phenotype of an offspring is influenced by the phenotype of its mother beyond the direct inheritance of alleles. Both maternal effects and imprinting may contribute to resemblance between offspring of the same mother. We demonstrate that two standard quantitative genetic models for deriving breeding values, population variances and covariances between relatives, are not equivalent when maternal genetic effects and imprinting are acting. Maternal and imprinting effects introduce both sex-dependent and generation-dependent effects that result in differences in the way additive and dominance effects are defined for the two approaches. We use a simple example to demonstrate that both imprinting and maternal genetic effects add extra terms to covariances between relatives and that model misspecification may over- or underestimate true covariances or lead to extremely variable parameter estimation. Thus, an understanding of various forms of parental effects is essential in correctly estimating quantitative genetic variance components. (+info)
Why some generations are more violent than others: assessment of age, period, and cohort effects.
(22/105)
Empirical longitudinal studies assessing why community-level violence rates change over time are lacking. Despite a wide-ranging literature, questions remain as to whether changes over time are due to factors occurring in specific periods (period effects) or individuals in successive cohorts (cohort effect). The objective was to assess the relative contribution of age, period, and cohort effects on violence trends. The authors assessed differences in self-reported violence between two cohorts of males (n = 1,009) from the Pittsburgh Youth Study, which tracked delinquency and risk factors from 1987 to 2000. The youngest cohort were aged 7-19 years, and the oldest cohort were aged 13-25 years. Yearly measures of violence were examined through generalized estimating equations. The oldest cohort reported higher levels of violence even after adjustment for age and major individual-level risk factors (odds ratio (OR) = 1.45, 95% confidence interval (CI): 1.17, 1.81) such as gang participation and drug dealing, as well as community-level factors (OR = 2.16, 95% CI: 1.65, 2.82). However, when period effects were included, cohort differences were rendered insignificant (OR = 1.23, 95% CI: 0.78, 1.94). The authors conclude that differences in the rates of violence over time may be attributed to changing social factors (period effects) and not to differences between the individuals (cohort effect) of cohorts. (+info)
The prevalence and correlates of eating disorders in the National Comorbidity Survey Replication.
(23/105)
BACKGROUND: Little population-based data exist on the prevalence or correlates of eating disorders. METHODS: Prevalence and correlates of eating disorders from the National Comorbidity Replication, a nationally representative face-to-face household survey (n = 9282), conducted in 2001-2003, were assessed using the WHO Composite International Diagnostic Interview. RESULTS: Lifetime prevalence estimates of DSM-IV anorexia nervosa, bulimia nervosa, and binge eating disorder are .9%, 1.5%, and 3.5% among women, and .3% .5%, and 2.0% among men. Survival analysis based on retrospective age-of-onset reports suggests that risk of bulimia nervosa and binge eating disorder increased with successive birth cohorts. All 3 disorders are significantly comorbid with many other DSM-IV disorders. Lifetime anorexia nervosa is significantly associated with low current weight (body-mass index <18.5), whereas lifetime binge eating disorder is associated with current severe obesity (body-mass index > or =40). Although most respondents with 12-month bulimia nervosa and binge eating disorder report some role impairment (data unavailable for anorexia nervosa since no respondents met criteria for 12-month prevalence), only a minority of cases ever sought treatment. CONCLUSIONS: Eating disorders, although relatively uncommon, represent a public health concern because they are frequently associated with other psychopathology and role impairment, and are frequently under-treated. (+info)
Adolescent participation in preventive health behaviors, physical activity, and nutrition: differences across immigrant generations for Asians and Latinos compared with Whites.
(24/105)
OBJECTIVES: We investigated preventive health behaviors (bicycle helmet, seat belt, and sunscreen use), physical activity, television viewing or video game playing, and nutrition (fruit, vegetable, milk, and soda consumption) among Asian and Latino adolescents living in the United States; assessed trends across generations (first-, second-, and third-generation immigrants or later); and compared each generation with White adolescents. METHODS: We used data from 5801 adolescents aged 12 to 17 years in the representative 2001 California Health Interview Survey. RESULTS: In multivariate analysis, first-generation Asians measured worse than Whites for preventive health behaviors (lower participation), physical activity (less activity), and television viewing or video game playing (more hours), but improved across generations. For these same behaviors, Latinos were similar to or worse than Whites, and generally showed no improvement across generations. First-generation Asians and Latinos had healthier diets than Whites (higher fruit and vegetable consumption, lower soda consumption). With succeeding generations, Asians' fruit, vegetable, and soda consumption remained stable, but Latinos' fruit and vegetable consumption decreased and their soda consumption increased, so that by the third generation Latinos' nutrition was poorer than Whites'. CONCLUSIONS: For the health behaviors we examined, Asian adolescents' health behaviors either improved with each generation or remained better than that of Whites. Latino adolescents demonstrated generally worse preventive health behaviors than did Whites and, in the case of nutrition, a worsening across generations. Targeted interventions may be needed to address behavioral disparities. (+info)