Smoking reduces wealth's tendency to increase life expectancy

"Our results suggest that even if wealth has a causal effect on mortality, it cannot compete with the impact of smoking. If you want to live longer, you better avoid the cancer sticks," said corresponding author Dana Glei, a senior research investigator at Georgetown University's Center for Population and Health.

The new study finds that the percentage of Americans surviving from age 65 to 85 was 19 percentage points higher for someone with at least $300,000 in wealth than for those with no assets. But there was a 37 percentage point difference between those who never smoked and current smokers. Due to how the data was collected, wealth was measured in 1995 dollars. $300,000 is the equivalent of $558,000 today.

The wealth-related disparity in mortality was larger than the disparities by education, occupation, income, or childhood socioeconomic status. But smoking made the greatest difference among all factors.

"Our finding further confirmed that smoking shortens our lives and that abstaining from smoking might be cheaper and more effective for living longer," said Chioun Lee, an assistant professor of sociology at UC Riverside.

Glei, along with Lee and Maxine Weinstein, a professor at Georgetown University, used data from 6,320 participants in the Midlife in the United States, or MIDUS, study funded by the National Institute on Aging to examine the effects of childhood socioeconomic status, education, occupation, income, wealth, and smoking history on mortality for adults aged 20-92 years old.

In fully adjusted models -- which also controlled for age, sex, race, marital status, health insurance coverage, employment status, and numerous health-related measures -- the researchers found that wealth outpaced all other measures of socioeconomic status associated with living past age 65. Mortality declined at higher levels of wealth, but wealth above $500,000 (in 1995 dollars) yielded no further mortality benefit. This amount is the equivalent of more than $925,000 today.

"We already know having a good education, a well-paid job, and extra savings are critical factors that help us live longer and stay healthier. Among education, occupation, income, and wealth, we found that wealth seems to be most important for longevity. However, beyond a certain amount, additional wealth may not yield extra years of life," said Lee.

For smokers, however, the picture was much grimmer. Above age 65, the mortality rate among current smokers was three times higher than never-smokers. Former smokers had significantly lower mortality than current smokers, but slightly higher mortality than never-smokers.

"Health care practitioners cannot modify their patient's wealth, but they should continue to discourage smoking. Wealth may be associated with longevity, but just don't smoke," said Glei.

The open-access paper, "Assessment of mortality disparities by wealth relative to other measures of socioeconomic status among us adults," is published in Jama Network Open.