Familial obesity as a proxy for omitted variables in the obesity-mortality relationship

Obesity and health expenditures: evidence from Australia

Rising rates of obesity are a public health concern in every industrialized country. This study investigates the relationship between obesity and health care expenditure in Australia, where the rate of obesity has tripled in the last three decades. Now one in four Australians is considered obese, defined as having a body mass index (BMI, kg/m(2)) of 30 or over. The analysis is based on a random sample survey of over 240,000 adults aged 45 and over that is linked at the individual-level to comprehensive administrative health care claims for the period 2006-2009. This sub-population group has an obesity rate that is nearly 30% and is a major consumer of health services. Relative to the average annual health expenditures of those with normal weight, we find that the health expenditures of those with a BMI between 30 and 35 (obese type I) are 19% higher and expenditures of those with BMI greater than 35 (obese type II/III) are 51% higher. We find large and significant differences in all types of care: inpatient, emergency department, outpatient and prescription drugs. The obesity-related health expenditures are higher for obese type I women than men, but in the obese type II/III state, obesity-related expenditures are higher for men. When we stratify further by age groups, we find that obesity has the largest impact among men over age 75 and women aged 60-74 years old. In addition, we find that obesity impacts health expenditures not only through its link to chronic diseases, but also because it increases the cost of recovery from acute health shocks.

Child and Adolescent Obesity and Employment Sector in Urban China

Despite its importance as a part of the economic reform in China, sectoral employment has been overlooked as a potential determinant of child and adolescent obesity (CAO). Using large-scale longitudinal data from surveys conducted from 1989 to 2006, this paper examines the relationship between the sector in which a parent is employed and CAO, with the sector being based on ownership and categorised as either state or non-state. Analyses of over 1,700 children and adolescents show that children and adolescents whose parents work in the state sector are less likely to be obese. Patterns of sectoral employment's effect are robust across time periods, in fixed-effects models, and across multiple measures of obesity. Additionally, the paper shows that socioeconomic characteristics of the parent, such as income, education, and occupation, typically thought to be important predictors of CAO, are not as important when the parental working sector is included in the models.

Similar associations of parental prenatal smoking suggest child blood pressure is not influenced by intrauterine effects

Maternal smoking in pregnancy may be associated with higher offspring blood pressure; however, results of previous studies have been inconsistent and included varying confounder adjustments. We studied the association between maternal smoking in pregnancy and offspring blood pressure at 7 years in the Avon Longitudinal Study of Parents and Children, accounting for important social and environmental confounders and using partner smoking to investigate intrauterine effects. Analysis was carried out in 6509 children with maternal smoking data and 7149 children with partner smoking data. In models adjusting for child age and sex, modest differences in systolic blood pressure were observed between children of mothers who did and did not smoke during pregnancy (beta=0.64 mm Hg; 95% CI: 0.09 to 1.20; P=0.02). Adjusting for all of the confounders attenuated this difference toward the null (beta=0.05 mm Hg; 95% CI: -0.59 to 0.68; P=0.9), mostly because of adjustment for breastfeeding, maternal education, and family social class. Associations were similar between maternal and partner smoking with offspring systolic blood pressure (for partner smoking: beta=0.62 mm Hg; 95% CI: 0.17 to 1.07; P=0.07 minimally adjusted and beta=0.26 mm Hg; 95% CI: -0.36 to 0.87; P=0.4 fully adjusted), providing further evidence that differences in child blood pressure observed in minimally adjusted models are not because of a biological influence of maternal smoking on the intrauterine environment.