Naltrexone versus acamprosate: One year follow-up of alcohol dependence treatment

Naltrexone and acamprosate reduce relapse in alcohol dependence. They have not yet been compared in a published trial. The aim of this study was to co mpare the efficacy of these compounds in conditions similar to those in rou tine clinical practice. Random allocation to a year of treatment with naltr exone (50 mg/day) or acamprosate (1665-1998 mg/day) was made in 157 recentl y detoxified alcohol-dependent men with moderate dependence (evaluated usin g the Addictions Severity Index and Severity of Alcohol Dependence Scale). All were patients whom a member of the family would accompany regularly to appointments. Alcohol consumption, craving and adverse events were recorded weekly for the first 3 months, and then bi-weekly, by the treating psychia trist who was not blinded. At 3-monthly intervals, investigators who were b linded to the treatment documented patients' alcohol consumption based on p atients' accounts, information given by the psychiatrists when necessary, a nd reports from patients' families. Serum gamma-glutamyltransferase (GGT) w as also measured. Efforts were made to sustain the blindness of the investi gators. The same investigator did not assess the same patient twice. The in tegrity of the blindness was not checked. There was no difference between t reatments in mean time to first drink (naltrexone 44 days, acamprosate 39 d ays) but the time to first relapse (five or more drinks in a day) was 63 da ys (naltrexone) versus 42 days (acamprosate) (P = 0.02). At the end of 1 ye ar, 41% receiving naltrexone and 17% receiving acamprosate had not relapsed (P = 0.0009). The cumulative number of days of abstinence was significantl y greater, and the number of drinks consumed at one time and severity of cr aving were significantly less, in the naltrexone group compared to the acam prosate group, as was the percentage of heavy drinking days (P = 0.038). Mo re patients in the acamprosate than the naltrexone group were commenced on disulfiram during the study. Naltrexone patients attended significantly mor e group therapy sessions, though this could not explain their better outcom e. There were non-significant trends for the naltrexone group to comply bet ter with medication, to stay in the study longer, and to show greater impro vement over baseline in serum GGT.