Adults under the age of 65 who lacked private health insurance were 35 percent more likely to die between 1986 and 1995 than similar adults who had such insurance, according to a new study examining factors associated with mortality in the United States.
Previous studies have highlighted the effects of income and education on mortality and both of these factors also have important links to heath insurance, according to three sociology professors in Colorado, Texas and Florida.
Income reduced the risk of death because it is used to purchase health insurance and products and services used to promote health and prevent disease, the study found. Education reduced the risk of dying because it provides the knowledge needed to obtain insurance coverage, either private or governmental, and to know what the insurance covered and did not cover.
The result is one of many findings contained in "Living and Dying in the USA," by Richard G. Rogers of the University of Colorado at Boulder, Robert A. Hummer of the University of Texas at Austin and Charles B. Nam of Florida State University. The book was published by Academic Press in October.
The authors examined the National Health Interview Study, which is given to 120,000 different people each year. They then linked the responses of everyone aged 18 years old and over in the study to mortality data for each year during the nine-year study period.
The professors examined the links between mortality and an array of possible factors including attending religious services, race, gender, family composition, mental health, smoking, alcohol consumption, exercise, functional limitations and health insurance coverage.
The 35 percent health insurance figure "is even more disturbing when the number of uninsured individuals is considered: in 1986, almost 31 million individuals aged 18 to 64 lacked private health insurance," the study found. Young and middle-aged adults who used Medicare or Medicaid also were more likely to die over the follow-up period.
The high mortality of individuals without health insurance may be due to their inability to get appropriate care during lapses or gaps in insurance coverage, or perhaps to other socioeconomic factors including unemployment and a lack of education, the study found. Individuals without health insurance also may delay seeking medical care, increasing the chance that a health condition will worsen and become life-threatening.
Overall, the authors emphasized the importance of social factors when examining the risk of dying. When researchers address the subject, they tend to focus on behavioral factors like smoking, proper diet and exercise, Rogers said.
"All of those factors are important but money may make a bigger difference," he said. "For example, factors that indirectly encourage people to smoke include low education, low income and unemployment. So socioeconomic factors must be underscored as important factors that influence mortality."
The study also found that foreign-born individuals of most U.S. ethnic groups had lower risks of death in the follow-up period compared to U.S.-born individuals of the same ethnic groups. This suggests that the generally low mortality of the foreign-born populations helps to maintain the largely favorable health profile of several U.S. ethnic groups, particularly Hispanics and Asian Americans.
Though not often discussed in debates about immigration policy, such patterns suggest that continued streams of healthy and select immigrants may be important in maintaining a health profile for several U.S. ethnic groups.
"The force of death is not the same for everyone," the study concluded.
"The force of death in the contemporary United States is stronger for the poor, the less educated, the unemployed and the uninsured than for the rich, the highly educated and the insured; for males rather than for females; for those who rarely attend religious services rather than for those who frequently attend; for those with mental and functional disorders and limitations rather than for those who are disorder and limitation-free; and for those who smoke, drink heavily and are inactive rather than for those who have never smoked, who drink moderately and exercise regularly."
The study was supported by the National Institute on Aging, the National Science Foundation and the National Center for Health Statistics.