Wealth Mobility, Both Positive and Negative, Could Influence Risk of Cardiovascular Events in Middle-Aged Patients

Muthiah Vaduganathan, MD, MPH

Using data from the RAND Health and Retirement Study (HRS), a new analysis is providing insight into how changes in midlife wealth, both negative and positive, can influence a patient’s risk of cardiovascular events.

Results of the analysis, which included more than 5500 patients without cardiovascular disease at baseline, suggested midlife wealth mobility, independent of baseline wealth, was associated with incident cardiovascular events.

"Low wealth is a risk factor that can dynamically change over a person's life and can influence a person's cardiovascular health status," said Muthiah Vaduganathan, MD, MPH, a Cardiologist at Brigham and Women’s Hospital, in a statement. ”So, it's a window of opportunity we have for an at-risk population. Buffering large changes in wealth should be an important focus for health policy moving ahead."

To describe the impact of changes in socioeconomic status might influence risk of cardiovascular events, Vaduganathan and colleagues from the University of Texas Southwestern Medical Center and London School of Economics designed their study as a longitudinal, retrospective cohort study using data obtained from 4 birth cohorts within HRS. Using cohorts from 1931-1935, 1936-1940, 1941-1945, and 1946-1950, investigators identified 42,052 participants for potential inclusion in their analyses.

As part of HRS protocol, all participants were surveyed every 2 years and these surveys record information related to changes in health and wealth. For the current analysis, investigators only included patients interviewed in at least 2 of the 5-year age intervals, which were defined as 50-54, 55-59, and 60-64 years, and who had follow-up after the age of 65 years.

Ultimately, 5579 participants without known cardiovascular disease were identified for inclusion. This cohort had a mean age at enrollment was 54.2 years, 55.2% were women, and 76.4% were White individuals.

For the purpose of analysis, participants were divided into quintiles according to wealth at the time of survey response for each 5-year interval. Wealth was defined as total nonhousing assets and was expressed in 2012 US dollars. Wealth mobility, both upward and downward, was defined as a change of at least 1 quintile.

"Income and wealth, while perhaps informally used interchangeably, actually provide different and complementary perspectives," said Sara Machado, PhD, an Economist at the Department of Health Policy at the London School of Economics. "Income reflects money received on a regular basis, while wealth is more holistic, encompassing both assets and debts. Could paying off one's debt with a large relative wealth increase be important in promoting cardiovascular health, even without changes in income?"

The bottom wealth quintile ranged from -$581,447 to $7460 and top wealth quintile ranged from $327,064 to $22,661,450. The primary outcome of interest for the analysis was a composite outcome of nonfatal cardiovascular events, which included myocardial infarction, heart failure, cardiac arrhythmia, or stroke, and cardiovascular death.

During a mean follow-up of 16.9 (SD, 5.8) years, 24% (n=1336) of participants experienced a primary outcome event (14.4 [95% CI, 13.6-15.2] per 1000 person-years).

Investigators noted those who started in the bottom quintile had an event rate of 15.3 per 1000 person-years and those who started in the top quintile had an event rate of 13.0 per 1000 years. Additionally, those who ended in the bottom quintile had an event rate of 17.6 per 1000 person-years compared to 12.3 per 1000 person-years among those who ended in the top quintile. In covariate-adjusted Cox proportional hazards regression models, higher initial wealth was associated with a lower cardiovascular risk (aHR per quintile, 0.89; 95% CI, 0.84-0.95; P=.001).

Results of the main analysis indicated participants who experienced upward wealth mobility had an independently lower risk of experiencing a primary outcome event (aHR, 0.84; 95% CI, 0.73-0.97; P=.02 and participants who experienced down wealth mobility had an increased risk of such an event (aHR, 1.15; 95% CI, 1.00-1.32; P=.046), when compared to those with stable wealth.

"Decreases in wealth are associated with more stress, fewer healthy behaviors, and less leisure time, all of which are associated with poorer cardiovascular health," said Andrew Sumarsono, MD, an Internal Medicine Resident from University of Texas Southwestern's Division of Hospital Medicine. "It is possible that the inverse is true and may help to explain our study's findings."

This study, “Midlife Wealth Mobility and Long-term Cardiovascular Health,” was published in JAMA Cardiology.