Neil K. Mehta

Weight Status and Restaurant Availability: A Multilevel Analysis

BACKGROUND Empiric studies find that contextual factors affect individual weight status over and above individual socioeconomic characteristics. Given increasing levels of obesity, researchers are examining how the food environment contributes to unhealthy weight status. An important change to this environment is the increasing availability of away-from-home eating establishments such as restaurants. METHODS This study analyzed the relationship between the restaurant environment and weight status across counties in the United States. Individual data from the 2002-2006 Behavioral Risk Factor Surveillance System (N=714,054) were linked with restaurant data from the 2002 U.S. Economic Census. Fast-food and full-service restaurant density, along with restaurant mix (the ratio of fast-food to full-service restaurants), were assessed. RESULTS Fast-food restaurant density and a higher ratio of fast-food to full-service restaurants were associated with higher individual-level weight status (BMI and the risk of being obese). In contrast, a higher density of full-service restaurants was associated with lower weight status. CONCLUSIONS Area-level restaurant mix emerged as an important correlate of weight status, with components of the restaurant environment exhibiting differential associations. Hence, it is the availability of fast-food relative to other away-from-home choices that appears salient for unhealthy weight outcomes. Areas with a high density of full-service restaurants were indicative of a more healthful eating environment, suggesting a need for research into the comparative healthfulness of foods served at different types of restaurants. Future prospective studies are required to delineate causal pathways.

Health Care Provider Recommendation, Human Papillomavirus Vaccination, and Race/Ethnicity in the US National Immunization Survey

OBJECTIVES Human papillomavirus (HPV) is a common sexually transmitted infection in the United States, yet HPV vaccination rates remain relatively low. We examined racial/ethnic differences in the prevalence of health care provider recommendations for HPV vaccination and the association between recommendation and vaccination. METHODS We used the 2009 National Immunization Survey-Teen, a nationally representative cross-section of female adolescents aged 13 to 17 years, to assess provider-verified HPV vaccination (≥ 1 dose) and participant-reported health care provider recommendation for the HPV vaccine. RESULTS More than half (56.9%) of female adolescents received a recommendation for the HPV vaccine, and adolescents with a recommendation were almost 5 times as likely to receive a vaccine (odds ratio = 4.81; 95% confidence interval = 4.01, 5.77) as those without a recommendation. Racial/ethnic minorities were less likely to receive a recommendation, but the association between recommendation and vaccination appeared strong for all racial/ethnic groups. CONCLUSIONS Provider recommendations were strongly associated with HPV vaccination. Racial/ethnic minorities and non-Hispanic Whites were equally likely to obtain an HPV vaccine after receiving a recommendation. Vaccine education efforts should target health care providers to increase recommendations, particularly among racial/ethnic minority populations.

Mortality Attributable to Obesity Among Middle-Aged Adults in the United States

Obesity is considered a major cause of premature mortality and a potential threat to the longstanding secular decline in mortality in the United States. We measure relative and attributable risks associated with obesity among middle-aged adults using data from the Health and Retirement Study (1992–2004). Although class II/III obesity (BMI _ 35.0 kg/m2) increases mortality by 40% in females and 62% in males compared with normal BMI (BMI = 18.5-24.9), class I obesity (BMI = 30.0-34.9) and being overweight (BMI = 25.0-29.9) are not associated with excess mortality. With respect to attributable mortality, class II/III obesity (BMI _ 35.0) is responsible for approximately 4% of deaths among females and 3% of deaths among males. Obesity is often compared with cigarette smoking as a major source of avoidable mortality. Smoking-attributable mortality is much larger in this cohort: about 36% in females and 50% in males. Results are robust to confounding by preexisting diseases, multiple dimensions of socioeconomic status (SES), smoking, and other correlates. These findings challenge the viewpoint that obesity will stem the long-term secular decline in U.S. mortality.

Obesity and muscle strength as long-term determinants of all-cause mortality—a 33-year follow-up of the Mini-Finland Health Examination Survey

Objective:To examine the independent and combined associations of obesity and muscle strength with mortality in adult men and women.Design:Follow-up study with 33 years of mortality follow-up.Subjects:A total of 3594 men and women aged 50–91 years at baseline with 3043 deaths during the follow-up.Measurement:Body mass index (BMI) and handgrip strength were measured at baseline.Results:Based on Cox models adjusted for age, sex, education, smoking, alcohol use, physical activity and chronic conditions, baseline obesity (BMI⩾30 kg m−2) was associated with mortality among participants aged 50–69 years (hazard ratio (HR) 1.14, 95% confidence interval (CI), 1.01–1.28). Among participants aged 70 years and older, overweight and obesity were protective (HR 0.77, 95% CI, 0.66–0.89 and HR 0.76, 95% CI, 0.62–0.92). High handgrip strength was inversely associated with mortality among participants aged 50–69 (HR 0.89, 95% CI, 0.80–1.00) and 70 years and older (HR 0.78, 95% CI, 0.66–0.93). Compared to normal-weight participants with high handgrip strength, the highest mortality risk was observed among obese participants with low handgrip strength (HR 1.23, 95% CI, 1.04–1.46) in the 50–69 age group and among normal-weight participants with low handgrip strength (HR 1.30, 95% CI, 1.09–1.54) among participants aged 70+ years. In addition, in the old age group, overweight and obese participants with high handgrip strength had significantly lower mortality than normal-weight participants with high handgrip strength (HR 0.79, 95% CI, 0.67–0.92 and HR 0.77, 95% CI, 0.63–0.94).Conclusion:Both obesity and low handgrip strength, independent of each other, predict the risk of death in adult men and women with additive pattern. The predictive value of obesity varies by age, whereas low muscle strength predicts mortality in all age groups aged>50 years and across all BMI categories. When promoting health among older adults, more attention should be paid to physical fitness in addition to body weight and adiposity.

Secular Declines in the Association Between Obesity and Mortality in the United States

Recent research suggests that rising obesity will restrain future gains in US life expectancy and that obesity is an important contributor to the current shortfall in us longevity compared to other high-income countries. Estimates of the contribution of obesity to current and future national-level mortality patterns are sensitive to estimates of the magnitude of the association between obesity and mortality at the individual level. We assessed secular trends in the obesity/mortality association among cohorts of middle-aged adults between 1948 and 2006 using three long-running US data sources: the Framingham Heart Study, the National Health and Nutrition Examination Survey, and the National Health Interview Survey. We find substantial declines over time in the magnitude of the association between obesity and overall mortality and, in certain instances, cardiovascular-specific mortality. We conclude that estimates of the contribution of obesity to current national-level mortality patterns should take into account recent reductions in the magnitude of the obesity and mortality association.

Projecting the Effect of Changes in Smoking and Obesity on Future Life Expectancy in the United States

We estimate the effects of declining smoking and increasing obesity on mortality in the United States over the period 2010–2040. Data on cohort behavioral histories are integrated into these estimates. Future distributions of body mass indices are projected using transition matrices applied to the initial distribution in 2010. In addition to projections of current obesity, we project distributions of obesity when cohorts are age 25. To these distributions, we apply death rates by current and age-25 obesity status observed in the National Health and Nutrition Examination Survey, 1988–2006. Estimates of the effects of smoking changes are based on observed relations between cohort smoking patterns and cohort death rates from lung cancer. We find that changes in both smoking and obesity are expected to have large effects on U.S. mortality. For males, the reductions in smoking have larger effects than the rise in obesity throughout the projection period. By 2040, male life expectancy at age 40 is expected to have gained 0.83 years from the combined effects. Among women, however, the two sets of effects largely offset one another throughout the projection period, with a small gain of 0.09 years expected by 2040.

Child health in the United States: Recent trends in racial/ethnic disparities

In the United States, race and ethnicity are considered key social determinants of health because of their enduring association with social and economic opportunities and resources. An important policy and research concern is whether the U.S. is making progress toward reducing racial/ethnic inequalities in health. While race/ethnic disparities in infant and adult outcomes are well documented, less is known about patterns and trends by race/ethnicity among children. Our objective was to determine the patterns of and progress toward reducing racial/ethnic disparities in child health. Using nationally representative data from 1998 to 2009, we assessed 17 indicators of child health, including overall health status, disability, measures of specific illnesses, and indicators of the social and economic consequences of illnesses. We examined disparities across five race/ethnic groups (non-Hispanic white, non-Hispanic black, Hispanic, non-Hispanic Asian, and non-Hispanic other). We found important racial/ethnic disparities across nearly all of the indicators of health we examined, adjusting for socioeconomic status, nativity, and access to health care. Importantly, we found little evidence that racial/ethnic disparities in child health have changed over time. In fact, for certain illnesses such as asthma, black-white disparities grew significantly larger over time. In general, black children had the highest reported prevalence across the health indicators and Asian children had the lowest reported prevalence. Hispanic children tended to be more similar to whites compared to the other race/ethnic groups, but there was considerable variability in their relative standing.

Modeling Obesity Histories in Cohort Analyses of Health and Mortality

There is great interest in understanding the role of weight dynamics over the life cycle in predicting the incidence of disease and death. Beginning with a Medline search, we identify, classify, and evaluate the major approaches that have been used to study these dynamics. We identify four types of models: additive models, duration-of-obesity models, additive-weight-change models, and interactive models. We develop a framework that integrates the major approaches and shows that they are often nested in one another, a property that facilitates statistical comparisons. Our criteria for evaluating models are two-fold: the model’s interpretability and its ability to account for observed variation in health outcomes. We apply two sets of nested models to data on adults age 50–74 years at baseline in two national probability samples drawn from National Health and Nutrition Examination Survey. One set of models treats obesity as a dichotomous variable and the other treats it as a continuous variable. In three of four applications, a fully interactive model does not add significant explanatory power to the simple additive model. In all four applications, little explanatory power is lost by simplifying the additive model to a duration model in which the coefficients of weight at different ages are set equal to one another. Other versions of a duration-of-obesity model also perform well, underscoring the importance of obesity at early adult ages for mortality at older ages.

Disability Among Native-born and Foreign-born Blacks in the United States

Using the 5% Public Use Micro Data Sample (PUMS) from the 2000 U.S. census, we examine differences in disability among eight black subgroups distinguished by place of birth and Hispanic ethnicity. We found that all foreign-born subgroups reported lower levels of physical activity limitations and personal care limitations than native-born blacks. Immigrants from Africa reported lowest levels of disability, followed by non-Hispanic immigrants from the Caribbean. Sociodemographic characteristics and timing of immigration explained the differences between these two groups. The foreign-born health advantage was most evident among the least-educated except among immigrants from Europe/Canada, who also reported the highest levels of disability among the foreign-born. Hispanic identification was associated with poorer health among both native-born and foreign-born blacks.

Continued increases in the relative risk of death from smoking.

OBJECTIVES We examined changes in the relative risk of death among current and former smokers over recent decades in the United States. METHODS Data from the National Health Interview Survey (NHIS) and National Health and Nutrition Examination Survey (NHANES) were linked to subsequent deaths. We calculated age-standardized death rates by gender and smoking status, and estimated multivariate discrete time logit regression models. RESULTS The risk of death for a smoker compared with that for a never-smoker increased by 25.4% from 1987 to 2006 based on NHIS data. Analysis of NHANES data from 1971 to 2006 showed an even faster annual increase in the relative risk of death for current smokers. Former smokers also showed an increasing relative risk of death, although the increase was slower than that among current smokers and not always statistically significant. These trends were not related to increasing educational selectivity of smokers or increased smoking intensity or duration among current smokers. Smokers may have become more adversely selected on other health-related variables. CONCLUSIONS A continuing increase in the relative risk of death for current and former smokers suggests that the contribution of smoking to national mortality patterns is not decreasing as rapidly as would be implied by the decreasing prevalence of smoking among Americans.