Aims: Cell-mediated immune function and the occurrence of mild infectious diseases was investigated. Participants Polydrug consumers of 3,4-methylenedioxymethamphetamine (MDMA) and cannabis (n = 37) compared to cannabis users only (n = 23) and control group (n = 34).
Design: A longitudinal prospective study with three cross-sectional evaluations at time 0 and at 6 months and 1 year was performed.
Findings: At baseline, a significant decrease in interleukin (IL)-2 and an increase in anti-inflammatory transforming growth factor (TGF)-beta1, together with a decrease in the number of total lymphocytes, CD4 and natural killer (NK) cells were observed in the MDMA-cannabis group, with intermediate alterations in the cannabis group. Immune alterations observed at baseline were sustained over time. No differences were found between regular and occasional MDMA users. A significantly higher rate of mild infections in regular MDMA-cannabis users compared with occasional MDMA-cannabis users and the remaining groups was observed.
Conclusions: The present data confirm that long-term alterations in immunological homeostasis may result in general health status impairment and subsequent increased susceptibility to infection and immune-related disorders.