ObjectiveTo examine the risk factors for new chronic opioid use in elderly patients who underwent hip fracture surgery.DesignProspective population-based cohort study.Setting and participantsUsing Danish nationwide health registries, we identified all opioid non-user patients aged ≥65 years who had undergone hip fracture surgery from 2005 to 2016 and were alive within the first year following surgery.Main outcome measuresNew chronic opioid use defined by the dispensing of at least two prescription opioids within two of the last three quarters during the first year following surgery.ResultsWe identified 37 202 opioid non-user patients who underwent hip fracture surgery. Of these, 5497 (15%) developed new chronic opioid user within 1 year of surgery. Risk factors for new chronic opioid use were Body Mass Index (BMI) of <18.5 (adjusted OR (aOR) 1.22, 95% CI 1.09 to 1.36), BMI of 25.0–29.9 (aOR 1.12, 95% CI 1.04 to 1.21) and BMI of ≥30 (aOR 1.57, 95% CI 1.40 to 1.76) with BMI 18.6–24.9 as reference, a pertrochanteric/subtrochanteric fracture (aOR 1.27, 95% CI 1.20 to 1.34) with femoral neck fracture as reference, preoperative use (vs no-use) of non-steroidal anti-inflammatory drug (aOR 1.68, 95% CI 1.55 to 1.83), selective serotonin reuptake inhibitor (aOR 1.42, 95% CI 1.32 to 1.53), antidepressants (aOR 1.36, 95% CI 1.24 to 1.49), antipsychotics (aOR 1.21, 95% CI 1.07 to 1.35), corticosteroids (aOR 1.54, 95% CI 1.35 to 1.76), statins (aOR 1.09, 95% CI 1.02 to 1.18), antibiotics (aOR 1.32, 95% CI 1.22 to 1.42), antiosteoporosis drugs (aOR 1.33, 95% CI 1.19 to 1.49) and anticoagulatives (aOR 1.24, 95% CI 1.17 to 1.32). Presence of cardiovascular comorbidities, diabetes, gastrointestinal diseases, dementia, chronic obstructive pulmonary disease or renal diseases was further identified as a risk factor.ConclusionIn this large nationwide cohort study, we identified several risk factors associated with new chronic opioid use after hip fracture surgery among patients who were alive within the first year following surgery. Although not all factors are modifiable preoperative, this will allow clinicians to appropriately counsel patients preoperatively and tailor postoperative treatment.