Introduction: Two conflicting randomized trials on surgery for degenerative lumbar spondylolisthesis (DLS) call for identification of patients who may benefit most from surgery. This study investigates the impact of obesity on patient reported outcomes (PROs) following surgery for DLS.
Methods: This was an analysis of 477 patients who underwent surgery for grade 1 DLS in a prospectively-collected national spine registry. For univariate comparisons, patients were stratified by BMI=>30 kg/m2 (obese) and <30 kg/m2 (non-obese). Baseline and one year follow-up parameters were collected. PROs included the North American Spine Society (NASS) satisfaction questionnaire, numeric rating scale (NRS) back pain, NRS leg pain, Oswestry Disability Index (ODI), and EuroQoL-5D (EQ-5D).
Results: We identified 224 obese (47.0%) and 253 non-obese patients (53.0%). Obese patients were younger (60.0 vs 63.3 years, p<0.01), more often had diabetes mellitus (25.4% vs 10.7%, p<0.01), and had higher ASA grades (56.3% vs 32.8% with ASA grades 3 or 4, p<0.01). Obese patients more often presented with sensory predominant symptoms (46.4% vs 38.9%, p=0.02) and were less independently ambulatory (82.5% vs. 93.7%, p<0.01). Obese patients more often underwent fusion surgery (87.9% vs 78.3%, p<0.01), had higher estimated blood loss (302.9±327.5 vs 213.3±227.0 ml, p<0.01), longer operative times (212.7±95.2 vs 177.2 ± 80.4 min, p<0.01), and longer hospitalizations (3.3±1.6 vs 2.9±2.0 days, p<0.01). At baseline, obese patients had worse NRS back pain, ODI, and EQ-5D scores (p<0.05). Both cohorts improved significantly from baseline for back and leg pain, ODI, and EQ-5D at 12 months (p<0.01). At 12 months, fewer obese patients responded that surgery met their expectations (64.4% vs. 70.1%, p<0.01). In adjusted multivariate analyses, increasing BMI was associated with worse NRS leg pain, ODI, and EQ-5D at 12 months (p<0.05).
Conclusions: Obesity was associated with worse pain, disability, and quality of life 12-months postoperatively. Preoperative weight loss may be considered to optimize outcomes.
Patient Care: This study helps to define patient populations that may benefit most from surgery for degenerative grade 1 lumbar spondylolisthesis. As obesity is associated with inferior outcomes, surgeons may utilize this data to encourage obese patients to pursue preoperative weight loss in order to optimize surgical outcomes.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Understand the negative impact of obesity on outcomes following surgery for grade 1 degenerative lumbar spondylolisthesis 2) Understand that despite the negative impact, patients with obesity still benefit significantly from surgery for grade 1 degenerative lumbar spondylolisthesis