Affordable Care Act linked to reduced smoking among US adults with mental health and substance use disorders

During the first decade following passage of the Affordable Care Act (enacted March 2010), U.S. adults with mental health and substance use disorders (MH/SUD) experienced significant increases in health insurance coverage. They also showed significant reductions in smoking and increases in recent smoking abstinence. A new study published by the journal Addiction has found that those two changes—increased health insurance coverage and improved smoking outcomes—appear to be linked.

This study, by a team that included researchers at Harvard Medical School/Cambridge Health Alliance, compared smoking and insurance coverage trends among almost 450,000 US adults with and without MH/SUD, using 2008-19 data from the National Survey on Drug Use and Health, an annual, cross-sectional survey.

The study's findings are among the first to identify meaningful, population-level reductions in smoking and increases in abstinence among adults with MH/SUD, a group that has maintained significantly higher smoking rates in recent decades despite public health measures and interventions that have driven change in the general adult population. A substantial proportion of the estimated improvements in smoking and abstinence outcome for those with MH/SUD can be explained by increases in health insurance coverage.

Changes in smoking

From 2008 to 2019, US adults with MH/SUD reduced their smoking and increased their abstinence rates more than those without MH/SUD.

Specifically, current smoking rates of adults with MH/SUD decreased from 37.9% to 27.9% while current smoking rates of adults without MH/SUD decreased from 21.4% to 16.3%, a significant difference in decrease of 4.9%. Daily smoking followed a similar pattern, with a difference in decrease of 3.9%. Recent smoking abstinence rates for adults with MH/SUD increased from 7.4% to 10.9% while recent smoking abstinence rates for adults without MH/SUD increased from 9.6% to 12.0%, a difference in increase of 1.0%.

Changes in health insurance availability

People with MH/SUD have historically had more limited access to care. Health insurance coverage for people with MH/SUD increased after 2014, when ACA provisions expanded the potential pool of individuals able to afford insurance coverage and improved evidence-based treatment options for those with insurance.

In 2008-09, the prevalence of insurance coverage was 6.2 percentage points lower for adults with MH/SUD (71.9%) than for adults without MH/SUD (78.2%). By 2018-19, that difference had shrunk to 2.0 percentage points.

The link between changes in smoking and changes in health insurance availability

This study found that in 2018-19, 11% of net reductions in current smoking, 12% of net reductions in daily smoking, and 12% of net increases in recent smoking abstinence coincided with greater gains in insurance coverage for adults with MH/SUD compared with adults without MH/SUD.

The study excluded adults who were 65 years or older and most likely to be covered by Medicare (public health insurance covering the elderly), and therefore less subject to most ACA provisions.