Behavioral health facilities have been slow to adopt smoke-free policies, partly because of arguments that cigarettes ease stress and anxiety in a vulnerable patient population. But that is changing as studies prove the specific harms that tobacco causes people with mental illnesses.

Two providers in Minnesota — Avivo and Mental Health Resources — announced that they would no longer allow patients or workers to smoke indoors or outdoors. People Inc. will add the policy, which was urged by the American Lung Association, this fall.

While 88 percent of Avivo patients smoke, most want to quit, said Kelly Matter, chief executive of Avivo, which operates outpatient mental health and chemical dependency clinics in the Twin Cities and central Minnesota. “Providers in the addiction treatment arena are uniquely positioned to provide tobacco cessation treatment as part of overall wellness support.”

Minnesota has lagged nationally in the share of mental health and substance abuse treatment programs that have smoke-free campuses, said a May report by the U.S. Centers for Disease Control and Prevention. Only 15.2 percent of the state’s substance abuse facilities were smoke-free in 2015, the third-worst rate in the nation.

Smoking rates have declined overall, but remain disproportionately higher among people with behavioral or substance abuse disorders. They smoke an estimated 44 percent of all cigarettes in the U.S.

The three mental health providers going smoke-free treat 40,000 patients and employ 1,400 people. All will receive access to counseling and nicotine patches.

The National Alliance on Mental Illness has favored removing tobacco from behavioral health facilities, noting that they have been “inappropriately accepted” and used by staff as rewards or coercion.

Studies have found that smoking can interfere with psychiatric drugs, requiring patients to take higher dosages that can increase side effects. Patients with mental health or substance abuse disorders who smoke are more likely to die from smoking-related illnesses than their conditions.

Despite these realities, smoking remains common among people with delusional disorders who mistakenly think that it helps, said Sue Abderholden, director of NAMI’s Minnesota chapter. “Some think it helps with stress and voices,” she said, when really its just “the nicotine addiction being filled.”