Dana A. Glei

Utilization of care during pregnancy in rural Guatemala: does obstetrical need matter?

This study examines factors associated with the use of biomedical care during pregnancy in Guatemala, focusing on the extent to which complications in an ongoing or previous pregnancy affect a womans decisions to seek care. The findings, based on multilevel models, suggest that obstetrical need, as well as demographic, social, and cultural factors, are important predictors of pregnancy care. In contrast, measures of availability and access to health services have modest effects. The results also suggest the importance of unobserved variables--such as quality of care--in explaining womens decisions about pregnancy care. These results imply that improving proximity to biomedical services is unlikely to have a dramatic impact on utilization in the absence of additional changes that improve the quality of care or reduce barriers to access. Moreover, current efforts aimed at incorporating midwives into the formal health-care system may need to extend their focus beyond the modification of midwife practices to consider the provision of culturally appropriate, high-quality services by traditional and biomedical providers alike.

The role of clinical risk factors in understanding self-rated health

PURPOSE This study examines the importance of clinical risk factors for predicting self-ratings of general health status, with and without controls for a broad range of self-reported indicators of physical and psychological well-being. METHODS Ordered probit models, estimated on 928 respondents aged 54 years and older who participated in an ongoing national survey in Taiwan, are used to examine the correlates of self-rated health. The model is estimated in two stages, first testing the association between clinical risk factors and self-rated health and second, examining whether those clinical measures remain significant after controlling for a large number of other factors hypothesized to affect self-ratings. RESULTS Most of the clinical variables are significantly associated with self-rated health, even in the presence of control variables. The largest effects pertain to the BMI, ratio of total to HDL cholesterol (among men) and presence of the epsilon4 allele of the APOE gene (among women). CONCLUSIONS The results suggest a variety of pathways linking clinical measures to the self-ratings. The findings also suggest that the clinical measures are less powerful predictors than self-reports about diverse aspects of well-being.

A new method for estimating smoking-attributable mortality in high-income countries

BACKGROUND Cigarette smoking is responsible for a massive loss of life in both developed and developing countries. This article develops an alternative to the Peto-Lopez method for estimating the number or fraction of smoking-attributable deaths in high-income countries. METHODS We use lung cancer death rates as an indicator of the damage caused by smoking. Using administrative data for the population aged > or =50 years from 20 high-income countries in the period from 1950 to 2006, we estimate a negative binomial regression model that predicts mortality from causes other than lung cancer as a function of lung cancer mortality and other variables. Using this regression model, we estimate smoking-attributable deaths based on the difference between observed death rates from lung cancer and expected rates among non-smokers. RESULTS Combining the estimated number of excess deaths from lung cancer with those from other causes, we find that among males in 1955 the smoking-attributable fraction was highest in Finland (18%); among women, no country exceeded 1%. By 2003, Hungary had the highest fraction of smoking-attributable deaths among males (32%), whereas the USA held that position among women (24%). Our estimates are remarkably similar to those produced by the Peto-Lopez method, a result that supports the validity of each approach. CONCLUSIONS We provide a simple and straightforward method for estimating the proportion of deaths attributable to smoking in high-income countries. Our results demonstrate that smoking has played a central role in levels, trends and international differences in mortality over the past half century.

Do Chronic Stressors lead to Physiological Dysregulation? Testing the theory of Allostatic Load

Objectives: To explore three questions: 1) Do chronic stressors predict physiological dysregulation? 2) Is that relationship moderated by characteristics of the individual and his or her social environment? and 3) Do perceived levels of stress mediate the relationship between stressors and dysregulation? Methods: Data come from a nationally representative, longitudinal study of older Taiwanese (n = 916). Regression models are used to examine the relationship between the number of life challenges (i.e., stressors) during 1996 to 2000 and physiological dysregulation (in 2000) based on 16 biomarkers that reflect neuroendocrine function, immune system, cardiovascular function, and metabolic pathways. We include interaction terms to test whether psychosocial vulnerability moderates the impact of stressors. Additional models evaluate the mediating effects of perceived stress. Results: We find a positive association between the number of stressors and physiological dysregulation. The results indicate that this relationship is stronger for persons with greater psychosocial vulnerability, but even so, the magnitude of the effect remains modest. We find some evidence that the level of perceived stress mediates the relationship between chronic stressors and physiological dysregulation. Conclusions: Our results provide some support for the theory of allostatic load, although the relationship between life challenges and physiological dysregulation is weak. The evidence also supports the stress-buffering hypothesis: the combination of low social position, weak social networks, and poor coping ability is associated with greater physiological consequences of life challenges. BMI = body mass index; DHEAS = dehydroepiandrosterone sulfate; HDL = high-density lipoprotein; HPA = hypothalamic-pituitary-adrenal; IGF-1 = insulin-like growth factor 1; IL-6 = interleukin-6; SD = standard deviation; SEBAS = Social Environment and Biomarkers of Aging Study; SEI = socioeconomic index; SNS = sympathetic nervous system; UCL = Union Clinical Laboratories.

Social Ties and Perceived Support: Two Dimensions of Social Relationships and Health Among the Elderly in Taiwan

Objectives: Assess the effects of social relationships on physical and mental health among the elderly in Taiwan. Methods: Using 4 waves of a survey of the elderly, we examine the relationship between social ties and perceived support and four health outcomes—mortality, functional status, self-assessed health, and depression. Results:Perceived support and social ties are related to health, but many of the apparent effects are attenuated in the presence of controls for prior health. However, positive perceptions about support are protective of mental (but not physical) health. Discussion: If baseline health is ignored, estimates of the effects of social relationships on health at a given stage of life are likely to be inflated by reverse causality or by effects occurring prior to baseline. Inclusion of controls for initial health reveals that, in general, the relationship between social support and health at the older ages in Taiwan is relatively modest.

A Comparative Analysis of Measurement Approaches for Physiological Dysregulation in an Older Population

The theory of allostatic load describes how the cumulative experience of emotional challenges and stressful events over the life course may take a significant physiological toll on multiple interrelated systems of the body. Various summary measures of these effects have been proposed in the literature, but few studies focus on systematically evaluating them. We use data from a population-based sample of older Taiwanese to compare the explanatory power and cross-sectional predictive performance of several measures of allostatic load for diverse health outcomes. We find that choices regarding which biomarkers to include in a summary measure and how the measure is formed have modest effects across the basic prediction models we evaluate. Our findings suggest that count-based summary measures incorporating risk at both high and low tails and measures that preserve the continuous properties of the biological variables are strategies that may yield stronger predictions of a wider array of health outcomes than other measures. These fundamental insights are useful for researchers in search of empirical formulations of allostatic load and for those who are focused on the development of improved measurement strategies.

The Serotonin Transporter Polymorphism (5-HTTLPR): Allelic Variation and Links with Depressive Symptoms

Background: We compare the genotype distribution for the serotonin transporter polymorphism (5‐HTTLPR) in a sample of older Taiwanese adults with samples of various racial and ethnic groups collected in other studies. We also explore interactions among sex, stressors, and 5‐HTTLPR genotype on depressive symptoms in our sample. Methods: Using a nationally representative sample of 984 Taiwanese aged 53 and older, we model depressive symptoms as a function of 5‐HTTLPR genotype and two classes of stressors: lifetime trauma and recent major life events. We test two‐ and three‐way interactions among stressors, 5‐HTTLPR, and sex. >Results: This sample exhibits higher frequency of S/S and lower frequency of L/L genotype than Western samples, but the distribution is comparable to those in East Asian populations. Nearly 9% carry an allele (XL) that has rarely been reported in the literature. Although the gene–environment (G×E) interaction with recent major life events is not significant, our results suggest that trauma has a worse effect on depressive symptoms for those with S/S or S/L genotype than for those who do not carry the S allele (P<0.05). We find no evidence that this G×E interaction varies by sex. Conclusions: Previous studies of this G×E interaction have been inconclusive, perhaps because interactions between genotype and stressful events are more prominent under extreme stressors. Our findings underscore the need to move beyond a bi‐allelic parameterization of the 5‐HTTLPR polymorphism and raise questions about why East Asian populations exhibit low rates of depression despite a high frequency of the S allele. Depression and Anxiety, 2010.

The narrowing sex differential in life expectancy in high-income populations: Effects of differences in the age pattern of mortality

Using data from the Human Mortality Database for 29 high-income national populations (1751–2004), we review trends in the sex differential in e(0). The widening of this gap during most of the 1900s was due largely to a slower mortality decline for males than females, which previous studies attributed to behavioural factors (e.g., smoking). More recently, the gap began to narrow in most countries, and researchers tried to explain this reversal with the same factors. However, our decomposition analysis reveals that, for the majority of countries, the recent narrowing is due primarily to sex differences in the age pattern of mortality rather than declining sex ratios in mortality: the same rate of mortality decline produces smaller gains in e(0) for women than for men because womens deaths are less dispersed across age (i.e., survivorship is more rectangular).

Evaluation of midwifery care: results from a survey in rural Guatemala

In an effort to reduce infant and maternal morbidity and mortality in developing countries, the World Health Organization has promoted the training of traditional birth attendants (midwives) and their incorporation into the formal health care system. In this paper, we examine several aspects of the integration of traditional and biomedical maternity care that are likely to reflect the quality of care received by Guatemalan women. Specifically, we examine the extent to which women combine traditional and biomedical pregnancy care, the frequency with which midwives refer women to biomedical providers, the content and quality of care offered by midwives, and the effects of midwife training programs on referral practices and quality of care. The analysis is based on data from the 1995 Guatemalan Survey of Family Health. The results offer a mixed assessment of the efficacy of midwife training programs. For example, although trained midwives are much more likely than other midwives to refer their clients to biomedical providers, most pregnant women do not see a biomedical provider, and the quality of midwife care, as defined and measured in this study, is similar between trained and untrained midwives.

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 Healtha 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.