Tramadol use and public health consequences in Iran: a systematic review and meta-analysis

Background and Aims Misuse of tramadol, an opioid prescription analgesic, is known as a public health challenge globally. We aimed to systematically review studies on the prevalence of non-prescribed use, regular tramadol use and dependence, tramadol-induced poisoning and mortality in Iran. Methods Consistent with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, international (Medline, Scopus, Web of Science) and Persian (SID) databases were systematically searched up to June 2019. Other relevant data were collected through personal contacts and review of reference lists. Pooled estimates of prevalence of tramadol use in subgroups of males and females, percentage of tramadol poisoning among admitted poisoning cases, tramadol-associated seizures and mortality among tramadol poisonings and percentage of tramadol as a cause of death among fatal drug-poisoning records were estimated through a random-effects model. Results A total of 84 records were included. Pooled estimates of last 12-month use of tramadol in the Iranian general population were 4.9% [95% confidence interval (CI) = 4.1-5.9] and 0.8% (95% CI = 0.2-1.8) among males and females, respectively. The estimates for last 12-month use among Iranian male and female university students were 4.8% (95% CI = 1.9-8.9) and 0.7% (95% CI = 0.3-1.1), respectively. Six heterogeneous reports indicated the existence of regular use of tramadol and dependence in Iran. Sixty-two studies provided data on tramadol-induced poisoning, seizures and mortality. The pooled estimate of the percentage of tramadol poisoning among all drug-poisoning patients was 13.1% (95% CI = 5.7-22.9). The overall estimates of seizures and mortality among tramadol-poisoning patients were 34.6% (95% CI = 29.6-39.8) and 0.7% (95% CI = 0.0-1.9), respectively. The pooled percentage of tramadol-related fatalities among drug-poisoned cases was 5.7% (95% CI = 0.5-15.4). Conclusion Despite control policies, tramadol use is as prevalent as the use of illicit opioids in Iran. Numerous cases of tramadol abuse, dependence, poisonings, seizures and hundreds of tramadol-related deaths have been reported in recent years.