Adolescent alcohol abuse and adverse adult outcomes: evaluating confounds with drinking-discordant twins.

BACKGROUND: Adolescent alcohol abuse is associated with adverse outcomes in early adulthood, but differences in familial status and structure and household and community environments correlate with both adolescent drinking and adverse adult outcomes and may explain their association. We studied drinking-discordant twin pairs to evaluate such confounds to ask: Will between-family associations replicate in within-family comparisons? METHODS: With longitudinal data from >3,000 Finnish twins, we associated drinking problems at age 18½ with 13 outcomes assessed at age 25; included were sustained substance abuse, poor health, physical symptoms, early coital debut, multiple sexual partners, life dissatisfaction, truncated education, and financial problems. We assessed associations among twins as individuals with linear regression adjusted for correlated observations; within-family analyses of discordant twin pairs followed, comparing paired means for adult outcomes among co-twins discordant for adolescent problem drinking. Defining discordance by extreme scores on self-reported problem drinking at age 18½ permitted parallel analyses of twins as individuals and discordant twin pairs. Alternate definitions of pair-wise discordance and difference score correlations across the entire twin sample yielded supplementary analyses. RESULTS: All individual associations were highly significant for all definitions of discordance we employed. Depending on definitions of discordance, 11 to 13 comparisons of all drinking-discordant twin pairs and 3 to 6 comparisons of discordant monozygotic (MZ) twin pairs replicated between-family associations. For most outcomes, effect size attenuated from individual-level analysis to that within discordant MZ twin pairs providing evidence of partial confounding in associations reported in earlier research. The exception was the General Health Questionnaire (GHQ); at age 25, GHQ-12 had equivalent associations with age 18½ Rutgers Alcohol Problem Index across all comparisons. CONCLUSIONS: Our analyses control for shared family background, and, partly or fully, for shared genes, to yield within-family replications and more compelling evidence than previously available that adolescent alcohol abuse disrupts transitions into early adulthood.

The differences in drinking patterns between Finnish-speaking majority and Swedish-speaking minority in Finland.

BACKGROUND: This study aims to examine whether the Swedish-speaking minority in Finland differ from the Finnish-speaking majority in respect to alcohol consumption and, whether such differences could be explained by aspects of social capital measured by both individual and area level variables. METHODS: This cross-sectional dataset consisted of 17,352 Finnish speakers (baseline response rate 40%) and 2018 Swedish speakers (baseline response rate 37%), aged 25-59 years. Multilevel logistic regression models were used to analyse the differences in alcohol consumption between the language groups, and to adjust for several potential individual and area level confounders. RESULTS: Finnish-speaking men and women reported more frequent drunkenness, suffered more frequent hangovers, and had alcohol-induced pass-outs significantly more often than men and women in the Swedish-speaking population. Demographic, social, or environmental factors did not explain the observed differences in drinking patterns between these groups. Active social participation, social engagement, and trust in others were significantly related to drinking patterns only among Finnish speakers, but not among Swedish speakers. CONCLUSIONS: Drinking patterns are likely to have a direct impact on the health differences between the two populations, especially in relation to alcohol-related acute harm. It seems unlikely that the effect of social capital on the health differences between the two populations would be mediated through drinking patterns.

Sexual behavior in young adulthood: a population-based twin study.

OBJECTIVE: With behavior genetic analyses of data from young adult twins, we evaluated theoretical perspectives that differentially emphasize biological dispositions, social/cultural factors, or universal pathways to explain individual differences in sexual behaviors. DESIGN: We fit biometric sex limitation models to three aspects of sexual behavior reported by 4,925 Finnish twins ages 23-27. MAIN OUTCOME MEASURE: From a postal questionnaire, we obtained self-report information on initiation/abstinence of sexual intercourse, onset age, and number of sexual partners. RESULTS: Genetic and non-shared environmental influences were significant for all three measures. There were trends for common environmental influences on initiation and, in females, age at first intercourse. Some differential effects in males and females were found. Results comparing onset age and number of partners among experienced twins from pairs concordant and discordant for initiation found genetic and environmental influences on initiation/abstinence overlapped those found for the other aspects of sexual behavior. CONCLUSIONS: These results document genetic variation in individual differences in sexual behavior of young adults. Incorporating genetic dispositions into integrated models of sexual behavior will facilitate more effective health promotion and risk taking intervention.

Associations between sexual abstinence ideals, religiosity, and alcohol abstinence: a longitudinal study of Finnish twins.

We analyzed prevalence and stability of attitudes endorsing sexual abstinence ideals from late adolescence into early adulthood and studied associations of these attitudes with religiosity and alcohol abstinence in a sexually liberal Nordic society. Our population-based sample of Finnish twins permitted comparisons of co-twins concordant for religiosity but discordant for drinking to evaluate the association of sexual abstinence ideals with alcohol abstinence, controlling for household environment. From age 17 to 24, endorsement of sexual abstinence as a romantic ideal declined from 25% to 15%. Religiosity and alcohol abstinence correlated, both separately and together, with endorsing sexual abstinence. Abstinence ideals were associated with literal belief in fundamental tenets of the Bible. The association of sexual abstinence ideals with alcohol abstinence was confirmed in within-family comparisons of co-twins discordant for drinking but concordant for religiosity. Alcohol-abstinent twins were significantly more likely than their non-alcohol-abstinent twin siblings to endorse sexual abstinence ideals; that result suggests the association of sexual abstinence ideals with abstaining from alcohol is not explained by unmeasured confounds in familial background and structure. Our longitudinal results and analyses of discordant twins suggest that attitudes toward sexual abstinence ideals are embedded within other conservative attitudes and behaviors.

Work-family conflicts and self-rated health among middle-aged municipal employees in Finland.

Work-family conflicts are common, but their effects on health are not well known. The aim of this study was to examine the associations between work-family conflicts and self-rated health among middle-aged municipal employees. In addition, the effect of social background factors on the association between work-family conflicts and self-rated health were examined. The data were based on cross-sectional postal surveys, which were carried out in 2001 and 2002, among female and male employees of the city of Helsinki, Finland. The participants were aged 40-60, and the response rate for women was 69%, and for men 60%. In the final analysis, 3,443 women and 875 men were included. For men and woman alike, work-to-family and family-to-work conflicts were associated with poor self-rated health. The association remained after adjusting for sociodemographic and socioeconomic factors. This study shows that a better balance between family life and work outside the home would probably have a health promoting effect.

Does religiousness explain regional differences in alcohol use in Finland?

AIMS: Because religiousness, a protective factor for alcohol use, is much more prevalent in rural regions, we examined its importance in explaining the differences in adolescent alcohol use found in the rural and the urban regions. In rural Ostrobothnia (hereafter referred to as the rural region), alcohol use is at the lowest level in all of Finland, whereas in Uusimaa, the urban region that surrounds Helsinki (hereafter referred to as the urban region), alcohol use is at the highest level. METHODS: We analysed cross-sectional questionnaire data collected from Finnish adolescents and their mothers, during 1991-1995. RESULTS: Abstinence was more prevalent, drinking less frequent, and religiousness higher in the rural region. In the urban region, there was but a negligible correlation between alcohol use and religiousness, whereas in the rural region, the correlation was clear, especially when abstainers were included. In modelling the relationship between region and adolescent abstinence, we found an interaction between mothers' religiousness and region: high religiousness among mothers was more protective of abstinence in the rural region. CONCLUSIONS: Our results show the importance of religiousness in explaining differences in adolescent alcohol use in regions with different religious traditions, but further studies will be required to explain why mothers' religiousness affects rates of adolescent abstinence differently in the two regions.

Femininity and fertility in sisters with twin brothers: prenatal androgenization? Cross-sex socialization?

Are sisters of twin brothers behaviorally or physiologically masculinized? Prenatal exposure to their brothers' androgens and postnatal socialization experiences unique to girls growing up with twin brothers might influence their attitudes, pubertal development, and reproductive histories. To investigate, we studied age- and cohort-matched samples of Finnish sisters from same-sex and opposite-sex twin pairs. Using data from two ongoing longitudinal studies of consecutive birth cohorts of Finnish twins, we assessed pubertal development at ages 11 and 14 and endorsement of attitudes associated with femininity at age 16. We also studied fertility in Finnish women from same- and opposite-sex twin pairs born from 1958 through 1971, obtaining information on their child-bearing histories when they were ages 15 to 28. Results of each comparison were unambiguously negative: There was no evidence of differences between sisters from same- and opposite-sex twin pairs, and thus, no evidence of either androgenization or cross-sex socialization.