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How Lack of Insurance Hurts Health and Wellbeing

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Northwestern University

Despite spending over twice as much on health care per person as any other nation, the United States remains the only wealthy country that fails to ensure health insurance coverage for all. The United States is also the only country where the value of health insurance is widely debated. As numerous Republican-led states refuse to accept federal funding to expand Medicaid to almost all of their low-income residents, conservative critics claim that such coverage is undesirable – in effect worse than going without any kind of health insurance. In the face of such claims, it is useful to summarize what research shows about the health benefits of insurance.

The Poor Health Consequences of Going without Insurance

Dozens of scientific studies conducted over more than four decades have documented that going without health insurance or having only intermittent coverage is a real detriment. Compared to insured adults:

  • Adults who are not continuously insured visit doctors less often and enjoy less preventative care, fewer mammograms, pap tests, cholesterol tests and influenza vaccinations.

  • With less access to routine and preventive care, the uninsured face a greater risk of sharp declines in general health and physical functioning, especially after age fifty.

  • The uninsured have been found to have much higher rates of undiagnosed high blood pressure and elevated cholesterol. They more often experience severe strokes and poorly controlled diabetes, and they tend to be diagnosed with cancer at more advanced stages.

  • When uninsured people end up in the hospital, they consistently have worse outcomes.

For example, uninsured patients hospitalized in an unconscious state after severe motor vehicle crashes found that they received less care and had a 40% higher mortality rate than insured patients, even after researchers took into account hospital characteristics, patients’ income level and residential neighborhoods, as well as the types of vehicles and injuries involved.

The Cost in Premature Deaths

Several recent nationally representative studies that followed late-middle-age adults into old age found that individuals who were uninsured died at younger ages than those of the same age and original health status who had private health insurance. The one-third greater mortality of older adults who lacked health insurance was roughly equivalent to the risk of smoking. If we counted “lack of health insurance” in late middle age as a health risk, it would rank as the third leading cause of death behind heart disease and cancer. According to one recent study, between 35,000 and 45,000 Americans aged 18-64 die annually due to lack of health insurance. Another study estimated that universal health insurance coverage would lower the premature death rate of those under age 64 from 6.7% to 3.9%.

Several studies have used the transition to Medicare insurance at age 65 to probe what difference it makes for the previously uninsured to gain coverage. When previously uninsured individuals finally became eligible for Medicare, they more regularly visit physicians and get more preventive and hospital care than individuals with the same personal and health characteristics who had enjoyed insurance coverage all along. Sharp declines in health also become less common for the previously uninsured.

Why are Doubters Still Arguing Against Expanded Coverage?

Detecting the specific consequences of lack of health insurance is difficult. At any given time, most uninsured people do reasonably well; and when stricken they can get treatment in emergency rooms or public hospitals or clinics. The fact that America does not literally let people visibly die in the streets leads some to argue that health insurance is not necessary.

Arguments have recently raged anew over early results from a widely publicized “Oregon Lottery Study.” With resources to expand Medicaid to 10,000 additional low-income residents, Oregon conducted a lottery among all who applied for the new coverage. Researchers have been able to measure early outcomes for lottery winners compared to losers.

  • Newly insured Oregonians more often visited physicians, got more cholesterol and blood sugar tests, and were more often diagnosed with diabetes and given appropriate medication. 

  • During the relatively short span of two years, measured control of diabetes, high blood pressure, and high cholesterol did not differ significantly for lottery winners and losers. 

  • Winners nevertheless enjoyed a 30% reduction in symptoms of depression, and they more often reported that their health was the same or better than the previous year. 

  • Winners had a 25% lower rate of unpaid medical bills sent to collection agencies and catastrophic expenditures were over 80% less than lottery losers. 

Opponents of Medicaid ignore financial gains and reduced depression levels, and point instead to insignificant differences in initial physical health measures. Not only do critics downplay very real gains, they also take no account of studies that have repeatedly found that people who report enhanced feelings of wellbeing are, in fact, likely to enjoy better health in the future.

A recent analysis by a researcher involved in the Oregon study found that U.S. states that expanded Medicaid coverage to low-income childless adults between 1997 and 2007 had a six percent decline in deaths among adults age 20-64 over the following five years, compared to states that did not expand the program. For every 176 additional adults covered, the study concluded, one death per year can be prevented. As numerous Republican-led states refuse to use Affordable Care funds to expand Medicaid, America will continue to pay the price that lack of insurance exacts in human life and wellbeing.

Research and data for this brief are drawnfrom J. Michael McWilliams, “Health Consequences of Uninsurance among Adults in the United States: Recent Evidence and Implications.” The Milbank Quarterly 87, no. 2 (2009): 443-494, and Benjamin D. Sommers, Katherine Baicker, and Arnold M. Epstein, “Mortality and Access to Care among Adults after State Medicaid Expansions.” The New England Journal of Medicine 367, no. 11 (2012).