Illegal Drug Use, Depressive Symptoms, and General Health: Exploring Co-occurrence across 11 Years in a National Sample.

The co-occurrence of illegal drug use, symptoms of depression, and a lower perception of general health among adolescents continues to be of substantive interest for researchers and the general public alike. Research on this topic, however, remains relatively stagnant, focusing on narrow developmental periods and each association independently, with limited consideration for the existence of a nexus between the three constructs as individuals age. Considering these limitations, the current study examines the longitudinal progression, from adolescence to early adulthood, of illegal drug use, symptoms of depression, and a lower perception of general health. The National Longitudinal Survey of Youth 1997 (NLSY97; N = 8,984), measures over an eleven-year data collection period, and between-and within-individual analytical strategies were used to evaluate the nexus between the constructs. The findings suggested that illegal drug use, depressive symptoms, and general health at previous time periods directly and indirectly predicted illegal drug use, depressive symptoms, and general health at subsequent time periods. Moreover, the within-individual change in illegal drug use was associated with the change in depressive symptoms, and the change in depressive symptoms was associated with the change in general health. Practitioners should consider this co-occurrence when treating symptoms related to illegal drug use, symptoms of depression, and physical health.