Obese Patients Benefit, but do not Fare as Well as Nonobese Patients, Following Lumbar Spondylolisthesis Surgery: An Analysis of the Quality Outcomes Database

Abstract BACKGROUND Given recent differing findings following 2 randomized clinical trials on degenerative lumbar spondylolisthesis (DLS) surgery, there is a need to better define how subsets of patients fare following surgery. OBJECTIVE To investigate the impact of obesity on patient-reported outcomes (PROs) following DLS surgery. METHODS A total of 12 high-enrolling sites were queried, and we found 797 patients undergoing surgery for grade 1 DLS. For univariate comparisons, patients were stratified by BMI ≥ 30 kg/m 2 (obese) and < 30 kg/m 2 (nonobese). Baseline, 3-mo, and 12-mo follow-up parameters were collected. PROs included the North American Spine Society satisfaction questionnaire, numeric rating scale (NRS) back pain, NRS leg pain, Oswestry Disability Index (ODI), and EuroQoL-5D (EQ-5D) Questionnaire. RESULTS We identified 382 obese (47.9%) and 415 nonobese patients (52.1%). At baseline, obese patients had worse NRS back pain, NRS leg pain, ODI, and EQ-5D scores ( P < .001, P = .01, P < .001, and P = .02, respectively). Both cohorts improved significantly for back and leg pain, ODI, and EQ-5D at 12 mo ( P < .001). At 12 mo, similar proportions of obese and nonobese patients responded that surgery met their expectations (62.6% vs 67.4%, P = .24). In multivariate analyses, BMI was independently associated with worse NRS leg pain and EQ-5D at 12 mo ( P = .01 and P < .01, respectively) despite adjusting for baseline differences. CONCLUSION Obesity is associated with inferior leg pain and quality of life—but similar back pain, disability, and satisfaction—12 mo postoperatively. However, obese patients achieve significant improvements in all PRO metrics at 12 mo.