Susan E. Short

Multiple Independent Loci at Chromosome 15q25.1 Affect Smoking Quantity: a Meta-Analysis and Comparison with Lung Cancer and COPD

Recently, genetic association findings for nicotine dependence, smoking behavior, and smoking-related diseases converged to implicate the chromosome 15q25.1 region, which includes the CHRNA5-CHRNA3-CHRNB4 cholinergic nicotinic receptor subunit genes. In particular, association with the nonsynonymous CHRNA5 SNP rs16969968 and correlates has been replicated in several independent studies. Extensive genotyping of this region has suggested additional statistically distinct signals for nicotine dependence, tagged by rs578776 and rs588765. One goal of the Consortium for the Genetic Analysis of Smoking Phenotypes (CGASP) is to elucidate the associations among these markers and dichotomous smoking quantity (heavy versus light smoking), lung cancer, and chronic obstructive pulmonary disease (COPD). We performed a meta-analysis across 34 datasets of European-ancestry subjects, including 38,617 smokers who were assessed for cigarettes-per-day, 7,700 lung cancer cases and 5,914 lung-cancer-free controls (all smokers), and 2,614 COPD cases and 3,568 COPD-free controls (all smokers). We demonstrate statistically independent associations of rs16969968 and rs588765 with smoking (mutually adjusted p-values<10−35 and <10−8 respectively). Because the risk alleles at these loci are negatively correlated, their association with smoking is stronger in the joint model than when each SNP is analyzed alone. Rs578776 also demonstrates association with smoking after adjustment for rs16969968 (p<10−6). In models adjusting for cigarettes-per-day, we confirm the association between rs16969968 and lung cancer (p<10−20) and observe a nominally significant association with COPD (p = 0.01); the other loci are not significantly associated with either lung cancer or COPD after adjusting for rs16969968. This study provides strong evidence that multiple statistically distinct loci in this region affect smoking behavior. This study is also the first report of association between rs588765 (and correlates) and smoking that achieves genome-wide significance; these SNPs have previously been associated with mRNA levels of CHRNA5 in brain and lung tissue.

Household Context and Subjective Well-Being Among the Oldest Old in China

This article investigates the importance of household context to subjective well-being among the oldest old (aged 80 years and older) in China. Using data from the Chinese Longitudinal Healthy Longevity Survey, the authors find that living arrangements have strong implications for elderly emotional health. First, living alone is associated with lower subjective well-being. Second, coresidence with immediate family (spouse or children) is associated with positive subjective well-being. Third, compared to living with a son, the traditionally dominant type of living arrangement, coresidence with a daughter appears positively linked to the emotional health of the oldest old. Results highlight the importance of family and cultural context to subjective well-being of the oldest old. They also suggest that the gendered nature of caregiving merits further attention in China and other patrilineal societies.

GENDER AND FAMILY BUSINESSES IN RURAL CHINA

The authors investigate the roles played by women and men in the emerging private sector in rural China. Specifically the authors explore gender and the allocation of labor in household-run businesses in the rural areas of eight provinces. Data collected in the China Health and Nutrition Survey (1989) indicate that households with a large pool of female labor are at no advantage in starting and running a small business; rather business involvement depends on the male labor pool especially the presence of older men. Furthermore if a household runs a business men are more likely than women to work in it. Men apparently have led the development and expansion of household business in rural China; while women increasingly specialize in agricultural activities. Possible reasons for these findings are discussed. (authors)

Looking locally at China's one-child policy.

Of all the reforms and policies set in motion in the early 1980s in China, the one-child policy has been called the most far-reaching in its implications for Chinas population and economic development. Almost two decades later, little is known about what the policy looks like across local neighborhoods and villages. To sketch a more general picture of the one-child policy, this article presents panel data from three waves of the China Health and Nutrition Survey (1989, 1991, and 1993) collected in 167 communities in eight provinces. Local policy, including policy strength and policy incentives and disincentives, is detailed separately for urban and rural areas. These data confirm that no single one-child policy exists; policy varied considerably from place to place and within individual communities during the 1989-93 period.

Grandmother Coresidence, Maternal Orphans, and School Enrollment in Sub-Saharan Africa

The HIV/AIDS pandemic in sub-Saharan Africa has brought renewed attention to the role of grandmothers as caregivers of children. Using 2004 Lesotho Demographic and Health Survey data, the authors examine the relationship between coresidence with a grandmother and child schooling in Lesotho, a country with one of the highest rates of HIV infection. Results confirm the critical role grandmothers play in the event of maternal death. Maternal orphans who live with a grandmother are just as likely to be in school as children living with a mother. The protective effect of living with a grandmother is also important for children whose mothers are alive but not affiliated with their households. The results of the analysis underscore the importance of attending to the simultaneous presence of mothers and grandmothers, as well as the circumstances associated with mother absence, when assessing the relationship between grandmother coresidence and child outcomes.

Use of maternal health services in rural China

We use data from the nationally representative 1997 Demographic and Reproductive Health Survey to examine use of maternity services in rural China. The data indicate that roughly 60 per cent of women had at least one prenatal visit, while 40 per cent had a professionally assisted birth over the period 1988–97. Despite Chinas shift from a more socialist to a more privatized health care system, use of maternity services increased over this period. These increases are consistent with the push toward integration of reproductive health into family planning that emerged after the 1994 International Conference on Population and Development and the 1995 Fourth World Womens Conference held in Beijing. At the same time, we find indirect evidence that the target-based population policy may well have exerted downward pressure on use of maternity services; differences by parity are marked and multilevel models predicting use of maternity services indicate underdispersion at the individual level.

Sex, gender, genetics, and health.

This article addresses 2 questions. First, to what extent are sex and gender incorporated into research on genetics and health? Second, how might social science understandings of sex and gender, and gender differences in health, become more integrated into scholarship in this area? We review articles on genetics and health published in selected peer-reviewed journals. Although sex is included frequently as a control or stratifying variable, few articles articulate a conceptual frame or methodological justification for conducting research in this way, and most are not motivated by sex or gender differences in health. Gender differences in health are persistent, unexplained, and shaped by multilevel social factors. Future scholarship on genetics and health needs to incorporate more systematic attention to sex and gender, gender as an environment, and the intertwining of social and biological variation over the life course. Such integration will advance understandings of gender differences in health, and may yield insight regarding the processes and circumstances that make genomic variation relevant for health and well-being.

Dynamic relations between fast-food restaurant and body weight status: a longitudinal and multilevel analysis of Chinese adults

Background Mixed findings have been reported on the association between Western fast-food restaurants and body weight status. Results vary across study contexts and are sensitive to the samples, measures and methods used. Most studies have failed to examine the temporally dynamic associations between community exposure to fast-food restaurants and weight changes. Methods Bayesian hierarchical regressions are used to model changes in body mass index, waist-to-height ratio (WHtR) and waist-to-hip ratio (WHpR) as a function of changes in Western fast-food restaurants in 216 communities for more than 9000 Chinese adults followed up multiple times between 2000 and 2009. Results Number of Western fast-food restaurants is positively associated with subsequent increases in WHtR and WHpR among rural population. More fast-food restaurants are positively associated with a future increase in WHpR for urban women. Increased availability of fast food between two waves is related to increased WHtR for urban men over the same period. A past increase in number of fast-food restaurants is associated with subsequent increases in WHtR and WHpR for rural population. Conclusions The associations between community exposure to Western fast food and weight changes are temporally dynamic rather than static. Improved measures of exposure to community environment are needed to achieve more precise estimates and better understanding of these relationships. In light of the findings in this study and Chinas rapid economic growth, further investigation and increased public health monitoring is warranted since Western fast food is likely to be more accessible and affordable in the near future.

Birth planning and sterilization in China

Sterilization is the most prevalent method of contraception in China. Approximately half of all women of reproductive age report that they or their husbands are sterilized. Using data from the China Health and Nutrition Survey we describe patterns of sterilization in eight Chinese provinces. With a discrete-time event history model we investigate the link between characteristics of local birth planning policy and the risk of sterilization. After controlling for parity, the risk of sterilization is highest in communities where birth planning policy is least strong as measured by exceptions to the one-child policy. These results suggest that couples with more flexibility in family building may have less control over contraceptive method use. Other factors affecting the risk of sterilization are a womans age, parity, and whether or not she has a son. Our results emphasize the importance of taking into account multiple dimensions of reproductive behaviour when assessing one-child policy changes.

Re-focusing the gender lens: caregiving women, family roles and HIV/AIDS vulnerability in Lesotho.

Gender and HIV risk have been widely examined in southern Africa, generally with a focus on dynamics within sexual relationships. Yet the social construction of women’s lives reflects their broader engagement with a gendered social system, which influences both individual-level risks and social and economic vulnerabilities to HIV/AIDS. Using qualitative data from Lesotho, we examine women’s lived experiences of gender, family and HIV/AIDS through three domains: (1) marriage; (2) kinship and social motherhood, and (3) multigenerational dynamics. These data illustrate how women caregivers negotiate their roles as wives, mothers, and household heads, serving as the linchpins of a gendered family system that both affects, and is affected by, the HIV/AIDS epidemic. HIV/AIDS interventions are unlikely to succeed without attention to the larger context of women’s lives, namely their kinship, caregiving, and family responsibilities, as it is the family and kinship system in which gender, economic vulnerability and HIV risk are embedded.