Renewed support and illuminating results for faculty-led research on cognitive decline in rural South Africa

Even after global setbacks from COVID-19, the average life expectancy continues to increase for humans everywhere. This is generally regarded as good news: Longer life typically correlates with access to wellness resources, social connections, and similar aspects of a healthy life. But a longer life doesn't necessarily translate to a better life—particularly if aging persons develop cognitive conditions that affect their ability to care for themselves and others. This important distinction drives ongoing research by Molly Rosenberg, Ph.D. of the Indiana University School of Public Health-Bloomington (SPH-B).

An associate professor in the Department of Epidemiology and Biostatistics, Rosenberg has spent the last several years exploring the relationship between socio-economic conditions and the development of Alzheimer's disease and related dementias (ADRD) in rural South Africa. Despite general gains in life expectancy, a grim statistic casts a shadow over this region: By 2050, about three-quarters of ADRD cases will occur in low- and middle-income areas such as these.

Rosenberg began investigating these issues in 2020 with more than $2 million in funding from the National Institute on Aging of the National Institutes of Health (NIH). The project tested whether cash transfer interventions affected memory decline and ADRD risk. The researchers suspected that when aging adults lived in households with more cash on hand, they would experience slower or less severe cognitive decline.

"These are remarkable findings," says Grace Sembajwe, Ph.D., interim chair of the Department of Epidemiology and Biostatistics. "They highlight tangible ways in which public health actions that may complement clinical interventions, can independently and definitively improve individual level health outcomes."

Meanwhile, the NIH recently funded a five-year renewal of the project, enabling Rosenberg and collaborators to leverage their initial findings into deeper understanding: "We want our work to tell us how cash transfers can protect cognitive health in older ages," Rosenberg says. "What are people investing their money in that could potentially be cognitively stimulating?"

There are implications beyond this rural setting, as well. Rosenberg explains that while most countries use some sort of cash transfer program to support people's financial well-being, "We want to understand the best way to structure cash transfer programs [for] the biggest impact on cognitive health. Are there certain life course periods that are more sensitive to the income? Certain members of households who are 'better' investments?"

The recent NIH renewal of funding for this study guarantees that Rosenberg and her colleagues will have important resources to examine these questions—and perhaps more. This means that the results of their investigation have the potential to inform both the development and administration of similar cash transfer programs in communities around the world.

"Groundbreaking research produced by dedicated faculty like you has a major influence," IU President Pamela Whitten said in a congratulatory letter to Dr. Rosenberg. "We are grateful for your dedication...to expanding knowledge that will have a positive, innovative impact on society—today and for generations to come."

For more stories about SPH-B making a big difference both locally and worldwide, visit go.iu.edu/48bx.