Methadone Maintenance Programs May Reduce Rates of Hepatitis C

Methadone Maintenance Programs May Reduce Rates of Hepatitis C


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Findings from a new study on hepatitis C (HCV) infection among individuals in methadone maintenance treatment add to the growing body of literature that shows that substance abuse treatment is effective not only for drug addiction but also for reducing risk for infectious disease.

Presented here at the American Society of Addiction Medicine (ASAM) 41st Annual Medical-Scientific Conference, investigators at the Dr. Miriam and Sheldon G.

Adelson Clinic for Drug Abuse Treatment & Research at the Tel Aviv Sourasky Medical Center in Israel found that among 207 HCV-negative patients admitted to the Tel Aviv clinic between 1993 and 2008, only 25 patients became HCV positive or 2.2 per 100 person-years of follow-up. Patients with at least 2 tests for HCV were followed up until their second test or seroconversion.

“The rate of seroconversion to hepatitis C we found in our study was low, and we hope it will stay that way,” lead researcher Einat Peles, PhD, told Medscape Psychiatry.

The investigators also examined the risk factors for hepatitis C seroconversion. Those risk factors that were the strongest predictors of HCV seroconversion were having been an injection drug user, benzodiazepine use on admission, and readmission to the methadone maintenance program, said Dr. Peles.

The seroconversion rate was significantly higher among the 118 patients who had been drug injectors, for the 103 patients with a urine test result positive for benzodiazepine use on admission to methadone maintenance, and among 43 patients who left treatment and then were readmitted.

“Specific interventions may be needed to reduce the risk of seroconversion among these high-risk groups,” Dr. Peles said. These interventions might include long-term medication treatment for addiction and monitoring for HCV, according to researchers here.

Lifelong Disease

“Addiction is a chronic, lifelong disease that may require lifelong medication — not just to treat the addiction but also to prevent infections such as hepatitis C,” commented Gavin Bart, MD, director of the Division of Addiction Medicine at the Hennepin County Medical Center and assistant professor of medicine at the University of Minnesota Medical School, Minneapolis.

Dr. Bart chaired the ASAM meeting and moderated the session at which the Israeli study was presented. “This is a very important study because it shows that not only does treatment work for the addiction itself but is a preventive measure for hepatitis C,” he said during an interview with Medscape Psychiatry. Dr. Bart added that that the study also supports continued monitoring or intermittent screening of those with risk factors for seroconversion to hepatitis C, such as continued drug use, he said.

In the study, Peles and fellow researcher Miriam Adelson, MD, found that the hazard ratio for being a drug injector was 3.9 (P = .002), for readmission to methadone maintenance treatment was 2.5 (P = .03), and for benzodiazepine abuse was 3.4 (P = .009).

There was also a trend toward greater risk for seroconversion among those who were female, those younger than 30 years, and those positive for hepatitis B, Dr. Peles said. She noted that methadone dose was not a risk factor for seroconversion to hepatitis C, and having children seemed to protect against seroconversion.

Dr. Bart pointed out that benzodiazepines tend to be a commonly abused drug in Israel, and substance abuse clinics there do not see the same prevalence of cocaine drug abuse as in the United States, for instance.

Signal for Infectious Disease Screening

“The risk factor for hepatitis C seroconversion isn’t specific to benzodiazepine use. The behavior that puts people at risk is ongoing drug use,” he said. Continued abuse of drugs — whether or not these drugs are injectable drugs, such as heroin — may be a signal to substance abuse counselors to recommend that these patients undergo screenings for infectious diseases, such as HCV, hepatitis B, and HIV, he said.

But all in all, the low rate of seroconversion to hepatitis C seen in the Israeli study is a validation of drug addiction treatments, such as methadone maintenance, Dr. Bart said.

“Hepatitis C is a huge epidemic among infection drug users with rates of 60% to 90%. So it’s good to know that those who get treatment are less likely to go on to get hepatitis C,” he added.

Dr. Peles and Dr. Bart have disclosed no relevant financial relationships.
American Society of Addiction Medicine (ASAM) 41st Annual Medical-Scientific Conference: Abstract 3. Presented April 16, 2010.
Medscape Today 19/4/2010