Disability in traditional versus modern contexts

Little is known about disability in traditional human populations, such as the Tsimane of Bolivia. The Tsimane are an Amazonian forager-horticulturalist group with high levels of physical activity and low prevalence of obesity and cardiovascular disease, but have high levels of inflammation, a life expectancy of only 54 years, and limited access to medical care. We use data from the Tsimane Health and Life History Project (N=610) and the Health and Retirement Study (HRS) (N=13,768) to compare the prevalence of limitations in four activities of daily living (bathing, dressing, eating, and going to the toilet) by sex and 5-year age groups from 50 to 70+ years. Each item was dichotomized to indicate a person either had no difficulty or had difficulty/could not perform the task. We used logistic regression to determine the odds of having at least one limitation for each age group, compared to those aged 50-54. In the US, only men and women aged 70 or older had 87% and 73% higher risk relative to the youngest age group while Tsimane men aged 70+ had 5.47 times higher odds. In contrast, among Tsimane women, odds of functional limitations were significantly higher among all age groups. Women aged 70+ had 15.42 times higher odds of at least one limitation. These results indicate that compared to the U.S. population, disability begins earlier and increases more rapidly among Tsimane women. Among men, differences in disability only become apparent at the oldest ages.