This article reports the results of a cross-national investigation of patterns of comorbidity between substance use and psychiatric disorders in six studies participating in the International Consortium in Psychiatric Epidemiology. In general, there was a strong association between mood and anxiety disorders as well as conduct and antisocial personality disorder with substance disorders at all sites. The results also suggest that there is a continuum in the magnitude of comorbidity as a function of the spectrum of substance use category (use, problems, dependence), as well as a direct relationship between the number of comorbid disorders and increasing levels of severity of substance use disorders (which was particularly pronounced for drugs). Finally, whereas there was no specific temporal pattern of onset for mood disorders in relation to substance disorders, the onset of anxiety disorders was more likely to precede that of substance disorders in all countries. These results illustrate the contribution of cross-national data to understanding the patterns and risk factors for psychopathology and substance use disorders.

To provide background information about previous findings about the prevalence of use, abuse and dependence of various substances (nicotine, alcohol, prescription and illicit drugs) findings of available epidemiological studies in Germany from the 1980s and 1990s are summarized and critically evaluated. Focusing on findings of substance use surveys in adolescents and young adults the review indicates: (a) a considerable number of large scale questionnaire surveys in general population samples documenting the frequency of use and patterns of use of most substances; (b) indications of increasing rates of drug use particularly in East Germany; (c) high rates of illicit drug use, mainly of cannabinoids, but also stimulants and hallucinogens, among young age groups. No data are available from substance use surveys or from clinical epidemiological studies allowing the determination of how frequent substance abuse and substance dependence diagnoses are in the general population or in adolescents and young adults. Priorities for future research to ameliorate this unsatisfactory situation are outlined with emphasis on research in adolescents and young adults.

To provide background information about previous findings about the prevalence of use, abuse and dependence of various substances (nicotine, alcohol, prescription and illicit drugs) findings of available epidemiological studies in Germany from the 1980s and 1990s are summarized and critically evaluated. Focusing on findings of substance use surveys in adolescents and young adults the review indicates: (a) a considerable number of large scale questionnaire surveys in general population samples documenting the frequency of use and patterns of use of most substances; (b) indications of increasing rates of drug use particularly in East Germany; (c) high rates of illicit drug use, mainly of cannabinoids, but also stimulants and hallucinogens, among young age groups. No data are available from substance use surveys or from clinical epidemiological studies allowing the determination of how frequent substance abuse and substance dependence diagnoses are in the general population or in adolescents and young adults. Priorities for future research to ameliorate this unsatisfactory situation are outlined with emphasis on research in adolescents and young adults.

This article reports the results of a cross-national investigation of patterns of comorbidity between substance use and psychiatric disorders in six studies participating in the International Consortium in Psychiatric Epidemiology. In general, there was a strong association between mood and anxiety disorders as well as conduct and antisocial personality disorder with substance disorders at all sites. The results also suggest that there is a continuum in the magnitude of comorbidity as a function of the spectrum of substance use category (use, problems, dependence), as well as a direct relationship between the number of comorbid disorders and increasing levels of severity of substance use disorders (which was particularly pronounced for drugs). Finally, whereas there was no specific temporal pattern of onset for mood disorders in relation to substance disorders, the onset of anxiety disorders was more likely to precede that of substance disorders in all countries. These results illustrate the contribution of cross-national data to understanding the patterns and risk factors for psychopathology and substance use disorders.