Epidemiology of Drug Dependence

If one judges solely by the cumulative table of contents of the official journal of the American College of Neuropsychopharmacology, Neuropsychopharmacology, the intersection where epidemiology meets neuropsychopharmacology is quite empty. When one looks elsewhere, the traffic becomes visible, with a scope that encompasses topics such as the characteristics of incarcerated drug users, adolescent drug use, epidemics of drug taking, the ‘‘overmedication’’ of American society, and postmarketing surveillance of new neuropsychopharmacologic drug products (e.g., see refs. 1–4). One of the possible reasons that epidemiologic research articles have been seen rarely in Neuropsychopharmacology is the generally nonexperimental and observational character of the studies. In this respect, epidemiology shares features of astronomy, geology, ecology, and other sciences in which the evidence comes mainly from field studies, without the benefit of maximal control over experimental error and sometimes with heavy reliance on retrospection. This reliance on retrospection has been a source of considerable criticism, and a countervailing trend has developed toward prospective, longitudinal, and even randomized experimental studies in epidemiology. Nonetheless, the scale and environment of epidemiologic research introduce constraints not seen elsewhere in human biology and the biomedical sciences, even when epidemiology harnesses the power of a randomized trial. Against a such a background, the primary goal of this chapter is to describe the focus of epidemiologic research in drug dependence and to elucidate the contributions that such research can make when connected with that in other areas of neuropsychopharmacology. A secondary goal is to aid neuropsychopharmacologists who may wish to know more about what can be learned by collaborating with epidemiologists. For focus, this overview concentrates on the clinical syn-