Changes in quality of life (WHOQOL-BREF) and addiction severity index (ASI) among participants in opioid substitution treatment (OST) in low and middle income countries: An international systematic review

Background: Opioid substitution treatment (OST) can increase quality of life (WHOQOL-BREF) and reduce addiction severity index (ASI) scores among participants over time. OST program participants have noted that improvement in quality of life is one of the most important variables to their reduction in drug use. However, there is little systematic understanding of WHOQOL-BREF and ASI domain changes among OST participants in low and middle-income countries (LMIC). Methods: Utilizing PRISMA guidelines we conducted a systematic literature search to identify OST program studies documenting changes in WHOQOL-BREF or ASI domains for participants in buprenorphine or methadone programs in LMIC. Standardized mean differences for baseline and follow-up domain scores were compared along with relationships between domain scores, OST dosage, and length of follow-up. Results: There were 13 OST program studies with 1801 participants from five countries eligible for inclusion in the review. Overall, statistically significant changes were noted in all four WHOQOL-BREF domain and four of the seven ASI domain scores (drug, psychological, legal, and family) documented in studies. Dosage of pharmacologic medication and length of follow-up did not affect changes in domain scores. Conclusion: WHOQOL-BREF and ASI domain scoring is a useful tool in measuring overall quality of life and levels of addiction among OST participants. Coupled with measurements of blood-borne infection, drug use, relapse, and overdose, WHOQOL-BREF and ASI represent equally important tools for evaluating the effects of OST over time and should be further developed as integrated tools in the evaluation of participants in LMIC.