I always find it hard to believe so many people are living in poverty: some 39.7 million Americans, or 12.3% of the population. It’s such a wealthy country, yet so many are poor.

In a twist that could be interpreted as good news — it doesn’t seem fair to say there is anything positive about living in poverty — I recently learned that older, low-income Americans tend to be healthier if they live in more affluent areas of the country.

Not only are they healthier, but their physical well-being is better across the board with a lower prevalence of dozens of chronic conditions, particularly if they live in rural communities. This, despite their income having less purchasing power in those better-resourced neighborhoods.

This was the key finding in new research published by Stanford Health Policy’s Maria Polyakova in the Annals of Internal Medicine.

While recent studies have reported that low-income adults living in more affluent areas of the United States have longer life expectancies, less has been known about the relationship between the affluence of a geographic area and morbidity of the low-income population.

“I was interested in figuring out whether the same relationship holds for morbidity: Are poorer people less sick in richer areas?” Polyakova told me. “And if so, are there any specific conditions that drive these differences that could be the target for policy-making?”

So Polyakova, a faculty fellow at the Stanford Institute for Economic Policy Research, and her co-author, Lynn M. Hua at the University of Pennsylvania, set out to evaluate the association between chronic conditions among low-income, older adults and the economic affluence of a local area. 

They focused on nearly 6.4 million Medicare beneficiaries in 2015 aged 66 to 100 years old who received low-income support under Medicare Part D, a prescription drug program for Medicare enrollees. They investigated the prevalence of 48 chronic conditions among these patients, including common chronic conditions such as hypertension, depression, diabetes and Alzheimer’s disease. They found the presence of all conditions is highly correlated: places, where the poor tend to have a high prevalence of one disease, are likely to have a high prevalence of all 48 conditions.

“While we cannot ascertain a causal relationship, our results clearly point towards the importance of further understanding why the socioeconomic environment of low-income, older adults is so tightly linked to such a broad measure of health,” the researchers wrote. 

The results, they said, were broadly consistent with the extensive literature on the social determinants of health. But their work takes that literature even further.

“Our study extends this research by providing measures of the prevalence of chronic conditions among low-income, older adults for a large national sample of the U.S. population,” Polyakova said. 

The researchers used clinical, rather than self-reported measures of diagnoses and reported this group’s variation in morbidity across local areas of the country, rather than nationally. 

“Our results raise the bar for researchers who are trying to find out what factors drive health disparities in the U.S.; these factors would have to be able to explain the differences in nearly 50 condition,” Polyakova said.

The study supported by the National Institute on Aging came to three key conclusions:

1. The health of low-income, older adults in the United States varies substantially across local geographic regions, and this variation cannot be attributed to one specific disease or a narrow set of conditions. 
2. Consistent with their original hypothesis, they found that more affluent local areas of the country have a lower prevalence of chronic conditions in the low-income, older adult population.
3. The researchers found that low-income, older adults have better health in rural areas of the country.

I wondered why these poor, older adults do particularly well in rural communities, as those regions often lack easy access to high-quality health care and state-of-the-art hospitals.

“We don’t know the exact answer, but there is a general sense that differences in the social fabric and lifestyle in rural areas — could contribute to this pattern,” Polyakova told me. “It appears that better health in these areas persists, despite challenges of accessing formal care.”