Treatment-seeking behaviour among people with opioid use disorder in the high-income countries: A systematic review and meta-analysis

OBJECTIVES: To determine treatment seeking behaviour in those with opioid use disorder (OUD) in the high-income countries. METHODS: Five databases were searched in November 2019 for quantitative studies that reported OUD treatment seeking behaviour. Data analysis involved determining an overall pooled proportion estimate of treatment seeking behaviour for the two base groups, lifetime treatment and past 12-month or less treatment using the IVhet effect model. Subgroup analysis included heroin OUD, prescription OUD and general OUD. The sensitivity analysis included removal of outliers, separating adults and adolescents and the metaXL sensitivity analysis (studies are excluded if outside the pooled proportion confidence interval of the base case). Systematic review Prospero database registration number [CRD42020159531]. RESULTS: There were 13 quantitative studies included in the systematic review, with all studies being from the United States of America (USA). IVhet models showed that 40% (95% CI: 23%, 58%) and 21% (95% CI: 16%, 26%) sought treatment in their lifetime and past 12 months respectively. Sub-group analysis found that lifetime treatment seeking for prescription OUD, 29% (95% CI: 27%, 31%), was less than for heroin plus combined OUD, 54% (95% CI: 26%, 82%). Most of the pooled results had high heterogeneity statistics except for results of lifetime treatment seeking for prescription OUD and past 12-month treatment seeking for prescription OUD. CONCLUSION: All included studies in this meta-analysis were from the USA and indicate modest levels of treatment seeking for those with OUD. In particular, this review found that in the USA one in five people with OUD sought OUD treatment in the previous 12 months and two in five people with OUD sought OUD treatment in their lifetime. Further research is urgently required to explore the barriers and facilitators that can improve this low treatment seeking in those with OUD.