Fluctuating personal income is also bad for your health

Study finds much wider gender pay gap

Fluctuations in personal income will likely harm your financial well-being, but more surprisingly, unpredictable changes in income are also bad for your physical health, a new study shows.

Long-term income volatility — a sudden and usually negative change in one's income over time — was shown to carry a nearly two-fold risk of cardiovascular disease and death, according an article based on the study, "Coronary Artery Risk Development in Young Adults" published in the American Heart Association's journal Circulation.

Researchers observed nearly 4,000 individuals ages 23-35 across four different American cities, assessing participants' income over a period of 15 years from 1990 to 2005. They subsequently followed the cohort for 10 years to assess cardiovascular incidents and mortality based on medical records and death certificates, Tali Elfassy, one of the study's lead authors, told CBS MoneyWatch.

The findings, which were adjusted to account for health factors such as subjects' body mass indexes and cholesterol levels, "reinforce the urgency and growing public health threat associated with income volatility in the United States," the study said.

Strong association

Its findings show a tight connection between fluctuating incomes and negative health outcomes. For example, the mortality rate was 5.28 per 1,000 patients for individuals with higher income volatility, compared to 2.12 per 1,000 patients with low income volatility.

"We were surprised by the strength of the association between income volatility and an increase in cardiovascular and premature mortality," Elfassy said.

Fluctuating incomes are on the rise in the U.S., where one-third of Americans weather large swings in income, according to research from The Pew Charitable Trusts.

The pervasiveness of income volatility is a pressing threat to public health, according to the study's authors. "Income volatility is very common, and it's something that needs to be considered in terms of cardiovascular disease risk since we are finding it is an independent contributor," Elfassy said.

Even financial gains can be negative, as changes in a family's income can hamstring their ability to plan financially.

More commonly, drops in income can lead to stress and affect patients' ability to manage their own care, leading to lapses in treatment or medication. "For example, low-income patients with chronic diseases may give up medications and medical visits to cope with unexpected financial instability, resulting in increased risk of disease, including heart attack and stroke," according to the study.

Multiple mechanisms

Elfassy said a number of criteria likely factor into the association.

"My hunch is that I don't think there is going to be just one particular biological or behavioral mechanism that will account for the entire association, but perhaps a number of them altogether will account for it," she said. "Each contributing factor may partially explain what we are seeing."

Unpredictable drops in income are also associated with all causes of mortality, according to the study. However, Elfassy noted that because the study's sample size was small and its participants were young, few mortalities were observed.

As far as possible remedies go, Elfassy suggested policies and programs to help individuals who experience traumatic financial events. "We should seek help and social coping mechanisms that deal with the implications of losing a substantial amount of income," she said.