Opioid analgesics prescribing in Latin America: systematic review and meta-analysis

BACKGROUND: Improving access to opioids in Latin America requires better understanding of prescription patterns in palliative care. AIM: To describe opioid prescribing patterns, including types and doses in morphine equivalent daily dose (MEDD), among patients receiving palliative care, including patients with cancer and non-cancer conditions in Latin America. DESIGN: Systematic review and meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES: We searched MEDLINE, EMBASE, PubMed, LILACS and SciELO from inception to January 2025. Quantitative studies reporting opioid prescriptions in adult patients receiving palliative care were included. Two reviewers independently screened, extracted data and assessed methodological quality using the Effective Public Health Practice Project tool. A narrative synthesis and descriptive statistics were conducted. Meta-analysis of MEDD was performed post hoc using random-effects models. RESULTS: Of 2855 records, 51 studies from seven countries met inclusion criteria. Most were observational (75%), with 8641 patients analysed. Cancer pain was the main indication (98%). Morphine (61%) and tramadol (15%) were the most frequently prescribed opioids. A meta-analysis of 48 studies (8433 patients) yielded a pooled mean MEDD of 98.06 mg (95% CI 77.07 to 119.05), with substantial heterogeneity (I²=100%). Most studies were rated as low to moderate quality. CONCLUSIONS: This review provides a regional synthesis of opioid prescribing patterns for palliative care in Latin America. Although morphine is the most used opioid, data show limited dosing variability and a scarcity of high-quality studies. Strengthening research capacity is essential to inform clinical guidelines and policy for equitable and adequate pain management in palliative care across the region. PROSPERO REGISTRATION NUMBER: CRD42024497564.