Drug Use and the Risk of Major Depressive Disorder, Alcohol Dependence, and Substance Use Disorders

Abstract

MANY CLINICAL and community studies have confirmed that there is a significant link between legal and illegal drug use and psychopathology.^1-24 Drug use itself has been found to be significantly related to substance use disorders(SUDs),^{3-8,11,13-15,25} including nicotine dependence,^1,3 anxiety, and affective disturbances.^{1,3-5,9,13,15,19,22,23} In fact, in general, drug users have both higher rates and more severe levels of psychological impairments than do individuals who do not use drugs.^1,4,7,17 Yet, despite the finding that drug use is related to psychiatric disorders, it has been unclear whether drug use precedes the development of psychiatric disorders.^2,15 A more complete delineation of the relationship between earlier drug use and later psychiatric disorders will contribute information for prevention and intervention.