Risk Factors for Prolonged Opioid Consumption in Lower Extremity Amputees

Extremity amputation is a common procedure performed to treat a variety of different problems and affects quality of life in a number of ways. In addition to acute postoperative pain, amputations have been shown to cause chronic pain that is often neuropathic in many amputees. This study sought to better characterize the role of opioids in postoperative pain control in lower extremity amputees. Patients who underwent lower extremity amputation between 2010 and 2018 were identified in a national insurance-claims database using ICD-9, ICD-10, and CPT codes. Patient demographics, comorbidities, perioperative opioid use, and prolonged postoperative opioid use were then determined for both groups. Descriptive statistics and logistic regression analysis were utilized to evaluate the association of patient-related risk factors and neuropathic pain conditions with perioperative and prolonged postoperative opioid use. In total, 2247 opioid-naive lower extremity amputees were identified. An estimated 54.7% of patients utilized opioids in the perioperative period, and 44.6% were found to have prolonged opioid use. Younger age (ages 40-50 versus older), history of chronic pain, migraines, lower back pain, Charlson Comorbidity Index greater than 1, preoperative benzodiazepine, muscle relaxant, anticonvulsant, and antidepressant use were all significantly related to prolonged postoperative opioid use. Prolonged postoperative opioid use is a problem that affects nearly half of lower extremity amputees and seems to be significantly related to the preoperative use of benzodiazepines, muscle relaxants, anticonvulsants, and antidepressants. Further research into the diagnosis and treatment of postamputation neuropathic pain is needed to prevent reliance on opioids in this patient population.