Back HCV Treatment Adherence to Hepatitis C Treatment among Recovering Heroin Users on Methadone Maintenance

Adherence to Hepatitis C Treatment among Recovering Heroin Users on Methadone Maintenance

As reported in the September 2007 issue of the European Journal of Gastroenterology and Hepatology, Diana Sylvestre, MD, from the University of California at San Francisco and colleagues evaluated the impact of mental health issues, active drug use, and other potential adherence barriers in a real-world sample of recovering drug users on methadone maintenance therapy.

Because hepatitis C virus (HCV) is easily transmitted via contaminated needles and other drug injection equipment, a large proportion of injection drug users (IDUs) have chronic hepatitis C.

However, IDUs are often denied treatment for hepatitis C due to concerns about adherence. This is the case despite limited and conflicting data about the impact on adherence of issues such as psychiatric conditions and concurrent illegal drug use. HCV treatment guidelines state that IDUs should not be excluded from treatment as a group, but that each individual should be evaluated for treatment on a case-by-case basis.

Some past studies have produced good sustained response rates for IDUs treated withinterferon-based therapy, but results from clinical trials do not always carry over into “real world” settings.

This prospective observational study included 71 patients on methadone maintenance who received interferon plus ribavirin combination therapy in a community-based clinic staffed by providers with expertise in treating addiction disorders. Adherence was assessed using monthly interviews, medication counts, and urine toxicology testing.

Results

  • Overall, 48 patients (68%) were adherent to anti-HCV therapy.
  • Adherent patients were significantly more likely than non-adherent patients to achieve a sustained virological response (42% vs 4%, respectively).
  • Patients with and without a prior psychiatric history had similar rates of adherence (64% vs 72%, respectively; P > 0.5).
  • Initiation of new psychiatric medications during HCV treatment was associated with improved adherence overall (P = 0.02) and in patients that did not have a pre-existing psychiatric diagnosis (P = 0.04).
  • There was a trend towards reduced adherence in patients without a period of drug abstinence before starting HCV treatment compared with those who had been abstinent for at least 1 month (46% vs 72%; P = 0.10).
  • Although occasional drug users were similarly adherent compared with those who were completely abstinent, patients who relapsed to regular drug use showed a significantly lower level of adherence (P = 0.03).

Conclusion

“We conclude that the majority of methadone-maintained drug users can adhere to HCV treatment, even those with psychiatric illness and relatively limited pretreatment drug abstinence,” the study authors wrote.

"Lack of pre-HCV treatment drug abstinence and regular drug use during HCV treatment may be relative barriers to medication adherence, but the initiation of psychiatric medications during HCV treatment may be a helpful intervention,” they added.

They concluded that, “This report provides further evidence for an individualized approach to HCV treatment that does not categorically exclude patients with potential barriers such as mental illness and limited drug abstinence.”

10/23/07

References

DL Sylvestre and BJ Clements. Adherence to hepatitis C treatment in recovering heroin users maintained on methadone. European Journal of Gastroenterology and Hepatology 19(9): 741-747. September 2007.