RT Journal Article SR Electronic T1 B347 Patient factors associated with opioid consumption in the 30 days following major surgery JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP A251 OP A251 DO 10.1136/rapm-2022-ESRA.421 VO 47 IS Suppl 1 A1 Koufopoulou, C A1 Savva, C A1 Kalogiannis, E A1 Stratigopoulou, P YR 2022 UL http://rapm.bmj.com/content/47/Suppl_1/A251.1.abstract AB Background and Aims New chronic opioid use may represent common complication after elective surgery.As many as 71% of opioid pills prescribed after surgery go unused and may become a source for misuse, abuse, and diversion.The aim of this study was to determine preoperative patient characteristics independently associated with home opioid use during the first postoperative 30 days.Methods 250 patients not taking opioids before major abdominal/thoracic surgery were included in this single-center prospective observational cohort study. Validated questionnaires to assess pain, catastrophizing, depression, anxiety, functional status, fatigue and sleep disturbance were applied preoperatively.Primary outcome was total opioid use in oral morphine equivalents (OMEs) assessed by self-report through phone calls at 2 weeks and 1 month after surgery.OMEs were standardized across all surgery types.Multivariate linear regression models were used to predict total OMEs consumed in the first 30 postoperative days.Results The median total OMEs prescribed was 600 mg (IR 450 mg), while median opioid consumption was 187.5 mg (IR 475 mg) 32 patients (13.0%) did not take any opioids after discharge;34 (13.4%) continued opioid use for 4 weeks.Older age, college graduate status and increased functional status were significantly associated with decreased opioid consumption (age:B coefficient -0.02 p<0.001;college graduate status:B coefficient -0.16 p=0.044;functional status:B coefficient -0.03 p=0.008).Higher anxiety scores were significantly associated with increased opioid consumption (B coefficient 0.05, p=0.002).Conclusions There was a marked discrepancy between prescribed and consumed opioids. Age, college graduates, more active, and less anxious patients consumed significantly fewer opioids during the first month after surgery.Physicians should consider adjusting postoperative prescribing amounts accordingly.