Background: The current study aimed at determining the pattern of drug dependence and its
related factors in mid-term residential treatment centers (MTRCs).
Methods: The current cross-sectional study was conducted on all drug dependent people
residing in MTRCs of Tehran, Iran, who were voluntarily seeking treatment from April to August,
2018. Required data were collected through face-to-face interviews. Drug dependence was
categorized into four groups: soft opioids, hard opioids, methamphetamine, and combination
of hard opioids and methamphetamine. The association of potential risk factors with drug
dependence was measured using chi-square test and multinomial logistic regression.
Results: Out of 1868 participants in the current study, 97% were male. Mean age (SD) of the
participants was 38.1 (9.9). The different types of drug dependence were hard opioids (43.0%),
soft opioids (29.5%), methamphetamine (15.4%), and a combination of hard opioids and
methamphetamine (12.1%). The prevalence of injecting drug use was 2.7%. In comparison with
the reference group (soft opioids), being un-married and unemployment, significantly increased
the risk of using the three groups of drugs (odds ratios [ORs]: 1.5-3.34, P values: <0.001-0.033).
Age ≥30 years at the initiation of drug use, and using current drug for more than 10 years,
significantly increased the risk of using hard opioids and a combination of hard opioids and
methamphetamine (ORs: 1.65-2.31, P values: <0.001-0.030). Age ≥50 years significantly
decreased the risk of using the three groups of drugs (ORs: 0.21-0.43, P ≤ 0.001).
Conclusion: Different pattern of drug dependence found in MTRCs, they were mostly hard
opioid users, lower injecting drug use and higher mean of age.