A developmental etiological model for drug abuse in men. (1st October 2017) - Kendler, Kenneth S.
Highlights: Drug abuse in men is a highly multifactorial syndrome. Drug abuse is influenced by a wide array of risk factors acting over development. Genetic and psychosocial risk factors for drug abuse are highly inter-twined. 70% of cases of drug abuse come from the top decile of risk. Abstract: Background: We attempt to develop a relatively comprehensive structural model of risk factors for drug abuse (DA) in Swedish men that illustrates developmental and mediational processes. Methods: We examined 20 risk factors for DA in 48, 369 men undergoing conscription examinations in 1969–70 followed until 2011 when 2.34% (n = 1134) of them had DA ascertained in medical, criminal and pharmacy registries. Risk factors were organized into four developmental tiers reflecting i) birth, ii) childhood/early adolescence, iii) late adolescence, and iv) young adulthood. Structural equational model fitting was performed using Mplus. Results: The best fitting model explained 47.8% of the variance in DA. The most prominent predictors, in order, were: early adolescent externalizing behavior, early adult criminal behavior, early adolescent internalizing behavior, early adult unemployment, early adult alcohol use disorder, and late adolescent drug use. Two major inter-connecting pathways emerged reflecting i) genetic/familial risk and ii) family dysfunction and psychosocial adversity. Generated on a first and tested on a second random half of the sample, a model from these variables predicted DA with an ROC area under the curve of 83.6%. Fifty-nine percent of DA cases arose from subjects in the top decile of risk. Conclusions: DA in men is a highly multifactorial syndrome with risk arising from familial-genetic, psychosocial, behavioral and psychological factors acting and interacting over development. Among the multiple predisposing factors for DA, a range of psychosocial adversities, externalizing psychopathology and lack of social constraints in early adulthood are predominant.