Background: Psychosocial factors have been considered important in the init
iation of drug abuse and seem to affect its clinical course and outcome. Se
veral studies have reported psychopathology, namely depression, to be consi
stently high in addiction. The aim of this investigation was to evaluate th
e prevalence of depression and its relationship to the severity of drug abu
se in a Portuguese sample of drug addicts. Methods: Two hundred and eighty-
five drug addicts (23 women and 262 men, aged between 16 and 41 years old),
diagnosed according to the DSM-IV criteria, were contacted during their fi
rst visit for treatment at public health centres. Social, demo graphic and
behavioural characteristics of the study sample were obtained by interview
using a structured questionnaire. The severity of drug abuse was evaluated
using a Portuguese version of the Drug Abuse Screening Test, and depression
was assessed by the Zung self-rating depression scale. Results: The preval
ence of depression was 51.2% and was higher in females than males (77.8 vs.
48.7%, p = 0.034), A significant correlation was also found between the se
verity of drug abuse and depression scores, which was also stronger in fema
les (r = 0.53 vs. r = 0.24). Conclusions: This study showed a high prevalen
ce of depression in drug addicts, regardless of the type and duration of dr
ug abuse, and a significant association between depression and severity of
drug addiction. Copyright (C) 2000 S .Karger AG. Basel.