Psychiatric disorders in first-degree relatives of patients with opiate dependence

High rates of psychiatric disorders, particularly major depression, alcohol ism, drug-use disorder and antisocial personality disorder in the relatives of opiate-dependent patients compared with normal controls, have been repo rted in some previous studies. This study was designed to evaluate the prev alence rates of drug-use and other psychiatric disorders in the first-degre e relatives of opiate-dependent patients and compare these with rates in th e first-degree relatives of surgical and psychiatric patients. A case-control study was conducted to compare the prevalence of psychiatric and drug-use disorders (which were estimated by the Family History Method) in 241 biological first-degree relatives of 50 opiate-dependent patients t o that in 235 and 222 first-degree relatives of 50 surgical and 50 psychiat ric patients respectively. The main outcome measure was the relative risk ( expressed as odds ratio) of psychiatric and drug-use disorders. First-degree relatives of opiate-dependent patients were found to have sign ificantly higher rates of drug-use and antisocial personality disorders, co mpared with relatives of surgical and psychiatric probands. The odds ratio for alcoholism appeared significantly higher only in first-degree female re latives of opiate users, suggesting effect modification by sex. The study provides further evidence for the higher rate of drug-use disorde r in the fu st-degree relatives of opiate-dependent patients. These finding s suggest that familial drug-use disorder contributes to a vulnerability to opiate misuse. Implications of these findings for the classification and treatment of opia te dependence are discussed.