Preoperative medications is one of the factor affecting patient-reported outcomes after total hip arthroplasty.

Although the reported clinical outcomes of total hip arthroplasty (THA) for hip osteoarthritis are satisfactory, not all patients are completely satisfied. Thus, there is interest in predicting postoperative satisfaction before surgery. The influence of comorbidities and preoperative medications on the incidence of complications and duration of hospitalization following THA has become apparent. However, studies about the associations of preoperative medication with clinical outcomes of THA are limited. Therefore, this study aimed to clarify the relationship between preoperative medications and postoperative patient-reported outcomes. This retrospective cross-sectional multicenter study enrolled post-THA patients (79 patients, 90 hips) who were examined from February to March 2019 in eight general hospitals. Outcome measures included patient-reported outcome as Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) score. Preoperative medications were investigated from medical records. Medications were categorized, and analgesics were categorized into non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen, pregabalin, duloxetine, neurotropin (an extract from inflammatory rabbit skin inoculated by vaccinia virus), and opioid. To identify the factors associated with JHEQ score, the patients were divided into lower (<55 score) and higher (≥55) JHEQ score groups. Spearman rank correlation coefficient (r) showed significant difference between the total number of preoperative medications and postoperative JHEQ movement subscale (r = -0.37, p < 0.01), mental subscale (r = -0.29, p < 0.01), and JHEQ (r = -0.30, p < 0.01) scores. In the multiple logistic regression analysis, only the total number of preoperative medications was identified as a risk factor for lower JHEQ score (p < 0.01). This study clarified an inverse correlation between the total preoperative medication count and postoperative outcomes and found that larger total count of preoperative medications is a risk factor of poor postoperative patient-reported outcomes of THA.