Association Between Preoperative Anxiety Scores and Postoperative Pain Severity in Elective Surgical Patients: A Systematic Review

Abstract

Background: Preoperative anxiety is common among patients undergoing elective surgery and may influence postoperative pain intensity, analgesic requirements, recovery, and patient satisfaction. However, the reported association varies because of differences in anxiety-assessment instruments, surgical procedures, anaesthetic techniques, analgesic protocols, and postoperative pain-assessment intervals. Objective: To systematically evaluate the association between validated preoperative anxiety scores and postoperative pain severity among adults undergoing elective surgery. Methods: This systematic review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. MEDLINE/PubMed, Embase, Scopus, Web of Science, PsycINFO, and the Cochrane Library were searched from database inception to 30 January 2026. Eligible studies included adults undergoing elective surgery, assessed anxiety before anaesthesia using a validated instrument, measured postoperative pain using a recognised pain scale, and evaluated the association between anxiety and pain severity or analgesic use. Two reviewers independently screened records, extracted data, and assessed methodological quality using the Quality in Prognosis Studies tool. Owing to substantial clinical and methodological heterogeneity, findings were synthesised narratively. Results: The search identified 504 records. After removal of 137 duplicates, 367 records underwent title and abstract screening, and 58 full-text reports were assessed for eligibility. Forty-one reports were excluded, leaving 17 primary observational studies for qualitative synthesis. Fourteen studies reported that higher preoperative anxiety was associated with at least one adverse postoperative pain-related outcome, including greater early pain intensity, increased opioid or rescue-analgesia requirements, or a higher occurrence of moderate-to-severe pain. The association was most consistent during the first 12–24 postoperative hours. State anxiety demonstrated a clearer relationship with acute postoperative pain and analgesic use than trait anxiety. In several studies, however, the association weakened after adjustment for expected pain, catastrophising, depression, baseline pain, surgical severity, anaesthetic technique, or analgesic regimen. Five studies had a low overall risk of bias, nine had a moderate risk, and three had a high risk. Conclusion: Higher preoperative anxiety is frequently associated with greater acute postoperative pain severity and increased analgesic requirements among adults undergoing elective surgery. The relationship appears strongest during the early postoperative period and is more consistent for state anxiety than for trait anxiety. Preoperative anxiety should be considered as part of a broader biopsychosocial pain-risk assessment. Routine screening may help identify patients who could benefit from targeted counselling, psychological preparation, closer postoperative monitoring, and individualised multimodal analgesia.