Measures of socioeconomic status have long been associated with the incidence of cardiovascular disease (CVD), with lower income people having a higher risk of cardiovascular events like heart attacks and strokes. Less clear has been whether part of the issue isn't that preventive services, such as blood pressure and cholesterol screenings, to reduce CVD risk are not used as often by people with less money.
To get a picture of how individuals at different income levels use or don't use preventive services, researchers at Johns Hopkins Hospital analyzed patient data from the Medical Expenditure Panel Survey (2006-2015). Their sample included nearly 33,000 adults diagnosed with cardiovascular disease and over 185,000 adults without CVD.
Thirty-six percent of those in the survey were in the high income category, 29 percent were in the middle income category, 16 percent were low income and 19 percent reported incomes placing them in the poor/very low income group. Income levels were based on individuals' earnings as a percentage of the Federal poverty line.
Healthcare disparities are often made worse during a crisis such as the COVID-19 pandemic, when low-income populations are often disproportionally affected, both economically and medically.
The less money a person had, the less likely they were to be given tests to prevent heart problems. Participants with low incomes and no CVD diagnosis were 58 percent less likely to have had their cholesterol checked within the last five years, compared to high income individuals. Similarly, they were 55 percent less likely to have had their blood pressure checked within the last two years, making higher income participants over twice as likely to receive preventive care.
The numbers were even greater for those with very low incomes and no CVD diagnosis: they were 64 percent less likely to have had their cholesterol checked within the last five years and 59 percent less likely to have had their blood pressure checked within the last two years, compared to those with high incomes.
The disparities in preventive testing were even more pronounced among those who had been diagnosed with cardiovascular disease. Participants with CVD and low and very low incomes were up to 68 percent less likely to have had their cholesterol checked within the last five years or their blood pressure checked within the last two years.
The quality of healthcare that people receive in lower versus higher income areas is likely one of the factors behind the lack of preventive testing. Hospitals serving poorer people are less likely than private practices to remind patients of the need for renewed testing. Lower income populations also tend to have more stress in their lives compared to higher income populations, whether due to poverty, discrimination or lack of a support system.
Another factor is the physical environment, explained Shahu. In general, transportation tends to be worse in low-income areas, so people there have a harder time getting to the doctor.
The less money a person had, the less likely they were to be given tests to prevent heart problems.
Going forward, researchers need to find ways to best study factors like quality of care, stress and the physical environment, so they can determine which of these is most relevant. “We need to think creatively about how we can dig deeper into the disparities we see, so we can better understand the underlying causes,” he said. The next step, which may not happen for years, is coming up with ways to close the economic gaps in preventive care.