Collaborative meta-analysis finds no evidence of a strong interaction between stress and 5-HTTLPR genotype contributing to the development of depression.

The hypothesis that the S allele of the 5-HTTLPR serotonin transporter promoter region is associated with increased risk of depression, but only in individuals exposed to stressful situations, has generated much interest, research and controversy since first proposed in 2003. Multiple meta-analyses combining results from heterogeneous analyses have not settled the issue. To determine the magnitude of the interaction and the conditions under which it might be observed, we performed new analyses on 31 data sets containing 38 802 European ancestry subjects genotyped for 5-HTTLPR and assessed for depression and childhood maltreatment or other stressful life events, and meta-analysed the results. Analyses targeted two stressors (narrow, broad) and two depression outcomes (current, lifetime). All groups that published on this topic prior to the initiation of our study and met the assessment and sample size criteria were invited to participate. Additional groups, identified by consortium members or self-identified in response to our protocol (published prior to the start of analysis) with qualifying unpublished data, were also invited to participate. A uniform data analysis script implementing the protocol was executed by each of the consortium members. Our findings do not support the interaction hypothesis. We found no subgroups or variable definitions for which an interaction between stress and 5-HTTLPR genotype was statistically significant. In contrast, our findings for the main effects of life stressors (strong risk factor) and 5-HTTLPR genotype (no impact on risk) are strikingly consistent across our contributing studies, the original study reporting the interaction and subsequent meta-analyses. Our conclusion is that if an interaction exists in which the S allele of 5-HTTLPR increases risk of depression only in stressed individuals, then it is not broadly generalisable, but must be of modest effect size and only observable in limited situations.

Association between child behavior problems and frequent physician visits.

OBJECTIVE: To determine the association between parent-reported behavior problems and health care utilization, especially among physically healthy children. DESIGN: Analysis of data from the 1988 National Health Interviews Survey--Child Health Supplement. The sample for analysis consisted of 11,840 children aged 5 to 17 years. The independent measure of primary interest are behavior problems as measured by the Behavior Problems Index. For the bivariate analysis, children in the lowest quartile, highest quartile and middle half were compared. For the multivariate analysis, children in the highest quartile with behavior problems were compared with all other children. MAIN OUTCOME MEASURES: The number of reported physician visits in the past year and the past 2 weeks, Two common behavior syndromes--antisocial and depressed or anxious--were analyzed separately to determine whether a specific type of behavior problem was associated with frequent health care utilization. RESULTS: Eighteen percent of the children aged 5 to 17 years had four or more health visits during the past year, and 2% had two or more visits during the past 2 weeks. Children in the top quartile for parent-reported behavior problems were more likely to have four or more physician visits than children in the middle half and bottom quartile. Children reported to be in "excellent," "very good," or "good" health who were in the top quartile of behavior problems were more likely to report four or more physician visits during the past year, but no statistically significant differences were seen among children reported to be in "fair" or "poor" health. Controlling for confounding variables, children in the top quartile of the Behavior Problems Index are significantly more likely to report four or more visits during the past year and two or more visits during the past 2 weeks compared with other children. Anxious or depressed and antisocial subscales of the Behavior Problems Index showed independent and significant associations with four or more physician visits in the past year. CONCLUSION: Children with parent-reported behavior problems are likely to have more frequent physician visits compared with children without behavior problems, even when confounding sociodemographic and health status variables are controlled. The association is concentrated among physically healthy children.

Measuring contraceptive use patterns among teenage and adult women.

CONTEXT: Measures of contraceptive use at one point in time do not account for its changing nature. A measure that addresses the pattern of method use over time may better predict the cumulative risk of unintended pregnancy. METHODS: Women at risk of unintended pregnancy were selected from the 1995 National Survey of Family Growth, and their contraceptive use patterns were compared across age-groups. Survival analysis was used to validate women's long-term use pattern as an indicator of pregnancy risk, and multivariate regression analyses were used to explore potential covariates of current patterns of contraceptive use. RESULTS: More than two-thirds of women aged 15-19 report long-term uninterrupted contraceptive use, but they are more likely to report sporadic use and less likely to report uninterrupted use of a very effective method than are women aged 25-34. Compared with women aged 25-34, women aged 20-24 have higher rates of sporadic use and lower rates of effective uninterrupted use. Among teenagers, nonusers are 12 times as likely as uninterrupted effective users to experience an unintended pregnancy within 12 months at risk. Women in less stable relationships, those having more infrequent intercourse and women who have recently experienced nonvoluntary intercourse for the first time are more likely than others to have a high-risk contraceptive pattern. Women aged 17 and younger whose current partner is more than three years older are significantly less likely to practice contraception than are their peers whose partner is closer in age. CONCLUSIONS: Long-term contraceptive use pattern is a valid predictor of unintended pregnancy risk. Policies aimed at reducing unintended pregnancies should target women who do not practice contraception and those who are sporadic users. Women in unstable relationships, those having infrequent sex and women who experience sexual coercion need access to methods, such as emergency contraception, that can be used sporadically or after unprotected intercourse.

PIP: This study examined determinants of unintended pregnancy in the US. Data were obtained from the 1995 National Survey of Family Growth among 7221 women 15-44 years old at risk of unintended pregnancy. Findings indicate that adolescents were not mainly sporadic method users in 1995. Most used a method without interruption for an extended period. Teenagers were more likely to report sporadic contraceptive use and were less likely to be uninterrupted users of effective methods. Women 20-24 years old were no more likely than 18-19 year old women to report long-term sporadic use and were more likely than women 25-34 years old to report long-term sporadic use. Nonusers and sporadic users contributed significantly to the high rate of unintended pregnancies. Logistic models reveal that women who were married or cohabiting were more likely to be uninterrupted effective contraceptive users than those not in long-term relationships. Frequency of intercourse had a consistent, strong positive relationship with contraceptive use. Women who had nonvoluntary intercourse and teenagers with significantly older partners were less likely to use contraceptives. Condoms are appropriate for infrequent intercourse, but couples must know the risks of pregnancy even with infrequent intercourse and know about postcoital methods of pregnancy prevention.

Understanding ethnic variation in pregnancy-related care in rural Guatemala.

OBJECTIVES: This study examines the relatively low use of modern pregnancy-related care in Guatemala, especially among indigenous women, and explores the role of socioeconomic status, social and cultural variables, and access to biomedical health facilities in accounting for ethnic differences in care. METHODS: The data for the analysis come from the Guatemalan Survey of Family Health--a population-based survey of rural women that contains detailed data on care received during pregnancy and delivery along with extensive background information. Binomial and multinomial logit models are used to identify the variables that affect the likelihood of receiving different types of care during pregnancy and delivering in a medical facility and the extent to which sociocultural factors and measures of access account for the observed ethnic differences. RESULTS: The estimates not only confirm previous findings of a large ethnic difference in the use of modern pregnancy-related care, but also extend them by identifying a gradient within the indigenous population. The analysis demonstrates that, in general, sociocultural variables are more strongly associated with modern pregnancy-related care than are measures of access and that the former variables explain more of the ethnic variation in care than the latter. The results also demonstrate that pregnant women, especially indigenous women, are more likely to seek biomedical care in conjunction with traditional midwifery care rather than to rely solely on the former. CONCLUSION: The findings suggest that midwives are likely to continue to be key providers of pregnancy-related care in the future, even as access to modern health facilities improves. Current efforts directed toward the training and integration of midwives into the formal health system are likely to be much more effective at improving pregnancy-related care than the replacement of midwives with biomedical providers.

Pregnancies averted among U.S. teenagers by the use of contraceptives.

CONTEXT: The personal and social costs associated with teenage pregnancy in the United States concern many policymakers and researchers, yet the role of contraception in preventing these pregnancies has not been adequately quantified. METHODS: Published estimates of contraceptive effectiveness were applied to 1995 National Survey of Family Growth data on sexual and contraceptive practices in order to estimate the number of pregnancies averted through the use of contraceptives by U.S. teenagers. Four scenarios of contraceptives access--from current levels of access to highly restricted access--and teenagers' sexual and contraceptive practices in response to such restrictions are used to project the potential impact on pregnancies among teenagers. RESULTS: Current levels of contraceptive use averted an estimated 1.65 million pregnancies among 15-19-year-old women in the United States during 1995. If these young women had been denied access to both prescription and over-the-counter contraceptive methods, an estimated one million additional pregnancies (ranging from 750,000 to 1.25 million) would have occurred, assuming some decrease in sexual activity. These pregnancies would have led to 480,000 live births, 390,000 abortions, 120,000 miscarriages, 10,000 ectopic pregnancies and 37 maternal deaths. CONCLUSIONS: Contraceptive use by teenage women prevents pregnancies and negative pregnancy-related health consequences that can disrupt the lives of adolescent women and that have substantial societal costs. Continued and expanded access to contraceptives for adolescents is a critically important public health strategy.

PIP: An analysis of the number of adolescent pregnancies and pregnancy outcomes that are averted in the US each year by contraceptive use highlighted the importance of continued and expanded access on the part of young people to contraception. In this analysis, published estimates of contraceptive effectiveness were applied to 1995 National Survey of Family Growth data on sexual and contraceptive practices among US teenagers. Four scenarios of contraceptive access--from current levels to highly restricted access--and sexual and fertility control practices in response to such restrictions were constructed. The 651 sexually active female adolescents enrolled in the national survey had used contraception during 80% of the times in which they were at risk of pregnancy. Current levels of contraceptive use averted an estimated 1.65 million pregnancies among 15- to 19-year-old US women in 1995. If these adolescents had been denied access to prescription and over-the-counter contraceptive methods, an estimated 750,000 to 1.25 million additional pregnancies would have occurred, assuming some decrease in sexual activity. These pregnancies would have resulted in 480,000 live births, 390,000 induced abortions, 120,000 miscarriages, 10,000 ectopic pregnancies, and 37 maternal deaths. The prevalence of adolescent sexual activity would have to decrease by 83% over current levels to avert the same number of pregnancies that are presently prevented by contraceptive use.