People suffering from mental health issues face numerous challenges in the United States, including limited access to mental health providers, shortages of psychiatric beds, and widespread incarceration. But another oft-overlooked issue harms the lives of millions of Americans with mental illness—cigarette smoking.

The national effort to reduce tobacco consumption has been cited among the foremost public health achievements in the last century—the percentage of American adults who smoke cigarettes dropped from 42 percent in 1965 to 15 percent in 2015, according to government statistics. But smoking rates remain high among people with mental illness. Recent surveys have found that over 30 percent of adults with mental illness smoked cigarettes in the last month. Estimates from the National Survey on Drug Use and Health suggest adults with mental illness or substance use disorders smoked nearly 40 percent of all cigarettes consumed by U.S. adults between 2009 and 2011.

These smoking habits are part of the reason why people with mental illness generally suffer from poorer health and shorter lives compared to the broader public. A 2015 systematic review of international studies found people who have mental disorders lose a median of 10 years from their life expectancies compared to others; much of this discrepancy appears to be due to chronic medical conditions that people with mental illness develop as a result of risk factors like smoking.

Why is smoking so prevalent among people with mental illness?

From a demographic standpoint, individuals suffering from mental health issues often fall into high-risk categories for smoking. In particular, mental illness is associated with lower household income, and people with lower incomes are far more likely to smoke compared to those with higher incomes. People with mental illness are also less likely to have access to health services, including routine preventive care that might discourage tobacco use, compared to the general population.

A longstanding belief is that many patients smoke to cope with symptoms of mental illness. In my training as a psychiatrist, I’ve met plenty of patients who tell me that tobacco helps distract them from depression, paranoia, auditory hallucinations or other psychiatric symptoms. For instance, some research supports the notion that smoking affects nicotine receptors and other brain networks that have been implicated in schizophrenia; the presumption has therefore been that smoking may alleviate some of the symptom burdens of schizophrenia, explaining high rates of smoking among people with this condition.

Tobacco companies seem to have encouraged these high smoking rates among individuals with mental health issues. According to researchers at the University of California, San Francisco, documents obtained by litigation against tobacco companies reveal that the industry sponsored a great deal of research behind the so-called “self-medication hypothesis.” The authors found that the tobacco industry had marketed cigarettes towards people with mental illness and had distributed cigarettes to psychiatric facilities.

An embedded culture of smoking in psychiatric facilities has also perpetuated tobacco use. It might seem unusual today for health care providers to embrace cigarettes; yet many psychiatric providers encouraged smoking because of the self-medication hypothesis and even provided cigarettes to patients as rewards for adhering to treatment in hospitals. Some mental health professionals went so far as to write letters to tobacco companies requesting more cigarettes for their patients. In the 1990s, the Joint Commission on Accreditation of Healthcare Organizations required that U.S. hospitals become smoke-free, but inpatient psychiatric and substance abuse facilities received exemptions from this smoking ban after protests from patients and advocacy groups.

Today, health care providers are often wary about smoking cessation for mental health patients. Since changes in smoking habits can affect the metabolism of medications like antipsychotics, a common fear is that smoking cessation may destabilize patients and their treatment regimens. However, clinical trials have found this isn’t always the case and that some patients may actually experience improved mental health after quitting smoking.

Further complicating the matter is that one of the few medications shown to help patients quit smoking—varenicline—carried a black box warning between 2009 and 2016 that the drug could worsen psychiatric symptoms. The Food and Drug Administration removed this warning after new findings suggested these side effects were less prominent than previously thought; even so, many clinicians remain uncomfortable prescribing varenicline to patients with psychiatric issues.

Another problem is that patients with mental health issues are frequently excluded from tobacco cessation research. Researchers may worry that participants with psychiatric histories will muddy the study results or make trials more difficult to conduct; however, these fears ignore the reality that people with mental illness represent a huge population of smokers that need to be included in these studies. Multiple addiction experts have called on researchers to include more people with mental illness in smoking cessation trials to better address this discrepancy.

Indeed, many smokers with mental illness are motivated to quit using tobacco. As an example, a 2011 survey of over 500 current smokers with bipolar disorder found 74 percent reported a desire to quit. And despite pervasive institutional and cultural barriers against quitting, there is considerable evidence that smoking cessation strategies like therapy and medications work for patients with mental health issues too.

Fortunately, these patients are not alone, and awareness around this issue is spreading. More psychiatric institutions are banning smoking inside and outside of their facilities. Public agencies including the Centers for Disease Control and Prevention are collaborating with academic organizations like the American Psychiatric Association around smoking cessation efforts. In 2017, Truth Initiative, a non-profit focused on curbing tobacco use, launched an ad campaign denouncing the tobacco industry for targeting people suffering from mental health issues.

The fight against tobacco has helped countless Americans lead healthier lives. People with mental illness deserve that chance too.