Risk factors for worsening sexual function after lumbar spine surgery and characteristics of non-responders to the questionnaire of sex life.

ABSTRACT

PURPOSE: To precisely assess the Oswestry Disability Questionnaire (ODQ) and its total score (Oswestry Disability Index ODI) and reveal characteristics of non-responders of the 8th item of ODQ (ODI-8) relating to sexual function. Furthermore, we evaluated risk factors for aggravation of postoperative sexual function. METHODS: We enrolled patients undergoing lumbar spine surgery at eight hospitals between April 2017 and November 2018. Patients' background data and operative factors were collected. We also assessed pain or dysesthesia (lower back, buttock, leg, and plantar area) on a numerical rating scale, EuroQol 5 Dimension, core outcome measures index back, and ODI before and 1 year after surgery. Factor analysis was conducted for the ODQ. Non-responders of the ODI-8 were compared with full-responders using propensity score matching. Risk factors for worsening ODI-8 were evaluated by multivariate logistic regression analysis. RESULTS: Of the 2,610 patients enrolled, 601 (23.0%) answered all but the ODI-8 item; these patients were likely to show better preoperative clinical symptoms than full-responders, even after adjusting for age and gender using propensity scores. Age, spinal deformity, and the American Society of Anesthesiologists physical status (ASA-PS) 3/4 were significant risk factors for postoperative aggravation of the ODI-8. Factor analysis revealed that the ODQ was composed of dynamic and static activities; the ODI-8 was considered a dynamic activity. CONCLUSION: Almost a fourth of the patients skipped the ODI-8. Age, the presence of spinal deformity, and worse ASA-PS were found to be risk factors for postoperative aggravation of sexual function. LEVEL OF EVIDENCE I Diagnostic individual cross-sectional studies with the consistently applied reference standard and blinding.