Midlife changes in wealth may affect a patient’s risk of cardiovascular disease, a new cohort study suggests.
It found that upward wealth mobility relative to peers was independently associated with protection against cardiovascular disease after age 65. In contrast, downward wealth mobility during middle age was linked to an increased risk of adverse cardiovascular events.
“A lot of studies have shown an inverse relationship between wealth and health in cross section at a single timepoint. What we really wanted to understand is whether this risk is modifiable and if this relationship changes over time,” senior author Muthiah Vaduganathan, MD, MPH, Brigham and Women’s Hospital Heart & Vascular Center, Boston, Massachusetts, said in an interview with theheart.org | Medscape Cardiology.
The results were published online June 15 in JAMA Cardiology.
For the primary analysis, the researchers collected data from 5579 US adults aged 50 years and older with no known cardiovascular disease at baseline who participated in the RAND Health and Retirement Study, a longitudinal survey that measures changes in health and wealth every 2 years. The participants had been interviewed in at least two of three 5-year age intervals (50-54, 55-59, 60-64 years) and had follow-up data available after age 65. Survey data from January 1, 1992 to December 31, 2016 was used.
Participants were grouped into quintiles based on wealth, defined as total nonhousing assets in 2012 US dollars, and were further stratified by birth cohort (1931-1935, 1936-1940, 1941-1945, 1946-1950). Upward relative wealth mobility involved an increase of 1 or more wealth quintiles during the observation period, while downward relative wealth mobility was defined as a decrease of 1 or more wealth quintiles. Participants who remained in the same quintile were described as having stable wealth.
Across the birth cohorts, the bottom wealth quintile ranged from –$581,447 to $7460 and the top wealth quintile ranged from $327,064 to $22,661,450.
Over a mean 16.9 years of follow-up, the primary outcome of cardiovascular death or a nonfatal cardiovascular event such as a heart attack or stroke occurred in 1336 participants, including 22.5% whose wealth increased by 1 quintile vs 28.1% whose wealth decreased by 1 quintile.
In adjusted analyses, higher initial wealth was associated with lower cardiovascular risk after turning 65 (adjusted hazard ratio [aHR] per quintile, 0.89; 95% CI, 0.84 – 0.95; P = .001). Additionally, experiencing relative upward wealth mobility by at least one quintile was independently associated with a lower risk of a nonfatal cardiovascular event or cardiovascular death, compared with stable wealth (aHR, 0.84; 95% CI, 0.73 – 0.97; P = .02).
Downward wealth mobility was associated with worse cardiovascular outcomes (aHR, 1.15; 95% CI, 1.00 – 1.32; P = .046). This effect was also observed on the risk of cardiovascular death in a secondary analysis of 3360 participants who had a previous history of cardiovascular disease (aHR, 1.48; 95% CI, 1.13 – 1.93; P = .004).
“We estimate that each $100,000 increase in wealth was associated with a roughly 1% lower hazard of cardiovascular outcome in follow-up,” the authors write.
The protective effect of wealth on cardiovascular health may be the result of factors such as “better access to care, having more time to adhere to a healthier diet or exercise regularly, and reduced stress” Kiarri Kershaw, PhD, a social epidemiologist at the Feinberg School of Medicine, Northwestern University, Chicago, Illinois, said in an interview. Kershaw, who was not involved in the study, added that, “stress can affect health through both biological and behavioral pathways.”
The study did not find a statistical relationship between race, wealth, and health. However, it was observed that the overall risk of cardiovascular events among non-Hispanic Black and Black participants was lower. The authors noted that “these findings are likely a byproduct of collider bias, in which Black and Hispanic participants who experience downward wealth mobility are more likely to experience barriers to care and subsequently less likely to receive a diagnosis of cardiovascular disease.”
Moving forward, the researchers plan to investigate health policy interventions that “best promote and sustain economic opportunity and wealth formed among low-income individuals,” Vaduganathan said.
The study was funded independently. Vaduganathan and Kershaw have disclosed no relevant financial relationships.
JAMA Cardiol. Published online June 15, 2021. Full text
Anna Goshua is a reporting intern with Medscape. She is a dual medical and journalism student who has previously written for STAT, Scientific American, Slate, and other outlets. She can be reached at [email protected] or @AnnaGoshua on Twitter .