Patient-Related Predictors of Opioid Use, Pain and Opioid-Related Adverse Events in the First 24 h After Surgery: A Systematic Review and Meta-Analysis

Background and Objectives: Acute postoperative pain is typically managed with titration of opioids, balancing pain intensity and opioid-related adverse events (ORADEs). Often, the dosing strategy is individualised based on the clinician's intuition or expertise. The influence of broader patient-related predictors remains insufficiently synthesised. This systematic review aimed to synthesise evidence on associations between patient-related predictors and opioid use, pain intensity and ORADEs within 24 h after surgery. Databases and Data Treatment: In this systematic review, we searched MEDLINE, Embase and CENTRAL for studies examining associations between patient-related predictors and opioid use, pain, or ORADEs within 0–24 h postoperatively. We used Quality in Prognosis Studies (QUIPS) for risk of bias and conducted meta-analyses. Results: We included 39 studies (294,221 patients) investigating 31 patient-related predictors. Meta-analyses showed that young age and chronic pain were associated with moderate–severe pain risk and large opioid consumption. Smoking, non-normal BMI, anxiety and preoperatively opioid use or pain were associated with moderate–severe pain. Female sex and lower ASA-scores were associated with postoperative nausea and vomiting. No other ORADEs were assessed. All but two studies were high risk of bias. Conclusion: The certainty of evidence was low due to high risk of bias and substantial heterogeneity in designs, populations and exposure/outcome definitions. Within 24 h after surgery, younger age, female sex, lower ASA score, smoking, abnormal BMI, anxiety, chronic pain and chronic opioid use were associated with greater postoperative complexity in terms of increased pain intensity, opioid use, or risk of nausea and vomiting. Significance Statement: This comprehensive review provides important understanding of patient-related predictors, which can contribute to a more individualised perioperative pain management, including dosing of preventive analgesia at the end of surgery and in adjusting as-needed opioid doses postoperatively. Prospero-Identifier: CRD42024559821.