Early-Life Conditions, Rapid Demographic Changes, and Older Adult Health in the Developing World.

The demographic transition of the 1930s-1960s dramatically improved life expectancy in some developing countries. Cohorts born during this time are increasingly characterized by their survivorship of poor early-life conditions, such as poor nutrition and infectious diseases. As a result, they are potentially more susceptible to the effects of these conditions at older ages. This study examines this conjecture by comparing obesity, diabetes, and hypertension in older adults born in the beginning portion of the 1930s-1960s across different mortality regimes using a subset of harmonized cross-national data from seven low- and middle-income countries (RELATE, n = 16,836). Using birthplace and height as indicators of early-life conditions, the results show (1) higher prevalence of obesity and diabetes and higher likelihood of obesity, diabetes, and hypertension in middle-income countries, but (2) no convincing evidence to indicate stronger effects of early-life conditions on health in these countries. However, shorter adults living in urban areas were more likely to be obese, indicating the overall importance of early-life conditions and the potential negative impact of urban exposures during adulthood. Obesity results may foreshadow the health of future cohorts born in the later portion of the 1930s-1960s as they reach older ages (60+).