Preoperative Risk Factors for Opioid Utilization After Total Hip Arthroplasty.

BACKGROUND: Opioid prescriptions following orthopaedic procedures may contribute to the opioid epidemic in the United States. Risk factors for greater and prolonged opioid utilization following total hip arthroplasty have yet to be fully elucidated. We sought to determine the prevalence of preoperative and postoperative opioid utilization in a cohort of patients who underwent total hip arthroplasty and to identify preoperative risk factors for prolonged utilization of opioids following total hip arthroplasty.

METHODS: A cohort study of patients who underwent primary elective total hip arthroplasty at Kaiser Permanente from January 2008 to December 2011 was conducted. The number of opioid prescriptions dispensed per 90-day period after total hip arthroplasty (up to 1 year) was the outcome of interest. The risk factors evaluated included preoperative analgesic medication use, patient demographic characteristics, comorbidities, and other history of chronic pain. Poisson regression models were used, and relative risks (RRs) and 95% confidence intervals (CIs) are presented.

RESULTS: Of the 12,560 patients who underwent total hip arthroplasty and were identified, 58.5% were female and 78.6% were white. The median age was 67 years (interquartile range, 59 to 75 years). Sixty-three percent of patients filled at least 1 opioid prescription in the 1 year prior to the total hip arthroplasty. Postoperative opioid use went from 88.6% in days 1 to 90 to 24% in the last quarter. An increasing number of preoperative opioid prescriptions was associated with a greater number of prescriptions over the entire postoperative period, with an RR of 1.10 (95% CI, 1.10 to 1.11) at days 271 to 360. Additional factors associated with greater utilization over the entire year included black race, chronic pulmonary disease, anxiety, substance abuse, and back pain. Factors associated with greater utilization in days 91 to 360 (beyond the early recovery phase) included female sex, higher body mass index, acquired immunodeficiency syndrome, peripheral vascular disease, and history of non-specific chronic pain.

CONCLUSIONS: We identified preoperative factors associated with greater and prolonged opioid utilization long after the early recovery period following total hip arthroplasty. Patients with these risk factors may benefit from targeted multidisciplinary interventions to mitigate the risk of prolonged opioid use.

CLINICAL RELEVANCE: Opioid prescriptions following orthopaedic procedures are one of the leading causes of chronic opioid use; strategies to reduce the risk of misuse and abuse are needed. At 1 year postoperatively, almost one-quarter of patients who underwent total hip arthroplasty used opioids in the last 90 days of the first postoperative year, which makes understanding risk factors associated with postoperative opioid utilization imperative.