The number of adults living beyond age 45 in sub-Saharan Africa is rapidly expanding, yet many of these older men and women experience physical illnesses and disabilities that limit their ability to function, according to a study by researchers at the University of Pennsylvania and in Malawi.

The research, conducted by Collin F. Payne, a doctoral candidate in demography at Penn; James Mkandawire of the Malawi research firm Invest in Knowledge; and Hans-Peter Kohler, the Frederick J. Warren Professor of Demography in Penn’s Sociology Department, shows that the physical limitations of a 45-year-old in Malawi are comparable to those of an 80-year-old in the United States.  

The study, “Disability Transitions and Health Expectancies among Adults 45 Years and Older in Malawi: A Cohort-Based Model,” is published in the May issue of the journal PLOS Medicine.

Using information from surveys conducted between 2006 and 2010, the researchers analyzed levels of disability and health expectancies among Malawi adults 45 and older.

They found that the likelihood of having a physical disability rapidly increased with age, with 45-year-old women in rural areas expected to spend 58 percent of their estimated remaining 28 years with functional limitations and 45-year-old men expected to live 41 percent of their remaining 25 years with functional limitations.

The authors also calculated that, on average, a 45-year-old woman in Malawi will spend almost three years of her life with a moderate functional limitation and more than six months with a severe functional limitation before she reaches 55. For a 45-year-old man in Malawi, the corresponding figures were one-and-a-half years and almost six months.

“Given the strong association of disabilities with work efforts and subjective well-being, this research suggests that current national health policies and international donor-funded health programs in sub-Saharan Africa inadequately target the physical health of mature and older adults,” Payne said.

Individuals in the population studied experienced a lengthy struggle with disabling conditions in adulthood, with high probabilities of “relapsing between states of functional limitation,” Payne said.

The research stresses the importance of investing in the health of older people to improve their ability to perform physical work in Malawi’s rural agricultural settings and ultimately boost the economy.

In an accompanying PLOS Medicine Perspective, Andreas Stuck from the University of Bern in Switzerland and his colleagues concluded that the study emphasizes that health policy should urgently address disability in older persons, an issue largely ignored.

They wrote, “Investments in improving health in older people will not only improve quality of life across generations but bring economic return for generations to come.”