麻豆传媒

AVENTURA, Fla. -- Veterans on methadone maintenance therapy who also had co-morbid serious mental illness used health services and filled prescriptions quite regularly, researchers reported here.

Out of more than 10,000 military veterans in methadone maintenance therapy, 33.2% also had a comorbid serious mental illness and they used available services, as well as filled their prescriptions on a routine basis, despite the perception that there is a general lack of compliance among these patients, said , and , both of Yale University, at the annual meeting.

"Patients who are dually diagnosed with both serious mental illness and substance use disorders are often perceived to have greater difficulty attending appointments, taking their medication; there's a stigma that exists around these patients that they don't actually use very much service, that they're hard to get to come in, they don't follow through with what they're supposed to do," Marienfeld said.

But the study results show that these assumptions "may not be the case," she added. "This could imply that the structure of methadone maintenance therapy leads to improved adherence to medications prescribed and possibly improved health outcomes."

However, the results do raise concerns about drug-drug interactions between methadone and psychiatric medications. "Further study and clinical awareness of potential drug-drug interactions in this high medication and service using population are needed," the authors cautioned.

Using data from the 2012 records of the Veterans' Health Administration (VA), Marienfeld and colleagues looked at patients in methadone maintenance treatment, patients with a serious mental illness, and patients who fell into both categories.

Marienfeld and colleagues defined serious mental illness as schizophrenia, bipolar disorder, or major affective disorder.

They found that according to the 2012 records, 510,722 veterans had bipolar disorder, schizophrenia, or a major affective disorder, and 10,001 veterans were in methadone maintenance therapy.

Only 0.65% of patients with a serious mental illness were also on methadone maintenance therapy. However, 33.2% of patients in methadone maintenance therapy also had a serious mental illness.

Compared with methadone maintenance therapy patients who didn't have a serious mental illness, methadone maintenance patients who did have a serious mental illness were more likely to:

• Have lower incomes
• Have been homeless
• Have higher rates of co-morbid psychiatric diagnoses
• Have had a recent psychiatric hospitalization
• Use more outpatient substance use services
• Have had more outpatient and emergency department visits
• Had more fills for psychotropic drugs

Compared with other patients with serious mental illness, methadone maintenance therapy patients with serious mental illness were more likely to:

• Be diagnosed with both HIV and liver disease (data coding did not distinguish hepatitis C
• Fill psychiatric medications
• Use outpatient substance use services
• Use outpatient psychiatric services
• Have had a mental health inpatient admission or emergency department visit

According to Marienfeld, significant predictors of having a serious mental illness while in methadone maintenance therapy included social factors, such as homelessness and VA service connection benefits status, psychiatric co-morbidity, service use such as having a mental health inpatient admission, and greater psychiatric medication usage.

"However, factors associated with being in methadone maintenance therapy among patients diagnosed with serious mental illness are somewhat different, the most prominent of which, not surprisingly, is having a drug use diagnosis," she said.

"Interestingly, having a mental health inpatient admission predicts both having serious mental illness in methadone maintenance therapy and being in methadone maintenance therapy if you have serious mental illness," Marienfeld said.

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