[Prevalence and predictors of psychoactive substance use among men in prisons]

The use of psychoactive substances among the prison population is an important public health issue because of its magnitude and health consequences. The aim of this study was to estimate the prevalence of psychoactive substance use among the prison population and to analyse its association with sociodemographic and penitentiary factors, particularly the size of the prison.

Data were gathered using a self-administered questionnaire among 2,484 random male inmates in eight prisons of different sizes in Spain. The prevalence of psychoactive substance use with 95% confidence intervals (95% CI) during the last 6 months in prison were estimated. Prevalence ratios were used to estimate the association between psychoactive substance use and sociodemographic and penitentiary characteristics.

The prevalence of psychoactive substance use in the past 6 months in prison was 59.9% (95% CI: 57.9-62.0). Notable among the sociodemographic variables associated with substance use were drug consumption prior to imprisonment (6.90; 95% CI: 5.51-8.65) and recidivism in prison (2.41; 95% CI: 2.04-2.85). The largest prisons showed a higher frequency of drug use than other prisons.

A high prevalence of psychoactive substance use was found in prisons and significant differences were found according to delinquent profile and the size of the prison.