Comorbid psychiatric disorders, sex, and methamphetamine use in adolescents: a case-control study.

The purpose of this case-control study was to elucidate the relative proportions of amphetamine use disorder (AUD) and amphetamine-induced disorder (AID) in a group of adolescents with the use of methamphetamine (MAMP) and to examine the risks for psychiatric comorbidity and sex for MAMP use. Psychiatric comorbidity in the preceding year was determined for 200 adolescent MAMP users and 400 drug-free control subjects by diagnostic interview using the Kiddie epidemiologic version of the Schedule for Affective Disorders and Schizophrenia. The proportions of AUD and AID were calculated, and the association between psychiatric comorbidity, sex, and MAMP use was assessed. The results revealed that among the MAMP users, 65 subjects (32.5%) had AUD, whereas 19 (9.5%) had AID. Early use of MAMP use was seen in AUD, whereas high-frequency MAMP use was associated with the occurrence of AID. Alcohol, nicotine, and betel nut use disorders were more prevalent in MAMP users for both sexes. By applying conditional logistic regression analysis, it was demonstrated that MAMP use was associated with conduct disorder in males, whereas in females, it was associated with conduct disorder and adjustment disorder. The results indicated that age of first use and subsequent frequency of MAMP use appeared to be associated with the development of amphetamine-related disorders. Sex differences in the association between psychiatric comorbidity and MAMP use were demonstrated. These factors have to be taken into consideration when intervening for adolescent MAMP use.