Identification of substance use and dependence among patients with viral hepatitis

Background: As drug abuse and addiction have been shown to decrease adherence to treatment of hepatitis C virus (HCV) or HIV, screening for substance use should be standard clinical practice in those undergoing an evaluation for these diseases. Aims: To assess the effectiveness of the Kreek-McHugh-Schluger-Kellogg (KMSK) scale to quantify substance use and dependence among patients with viral hepatitis. Methods: The KMSK scale, a validated instrument that quantifies lifetime use of alcohol, cocaine, heroin, and tobacco, was distributed to 161 consecutive patients referred to a hepatology clinic at an academic, tertiary-care center over a 1-year period. Results: Of the 159 patients who returned the KMSK scale, 62% reported illicit drug use and 30% met defined criteria for lifetime dependence on cocaine or heroin. We found that 15% of our population at some time had been co-dependent on cocaine and heroin. The KMSK scale identified significantly more cocaine, heroin, and alcohol use than that detected through the medical record (χ²=7.61, p<0.01, χ²=9.66, p<0.002, respectively). Cocaine dependence was significantly higher among HCV/HIV co-infected than among mono-infected patients (χ²=5.46, p<0.02). Conclusions: The KMSK scale may be useful to diagnose drug and alcohol use and dependence among patients undergoing evaluation for treatment of viral hepatitis.