Objective: The aim of this study was to compare the rate of achievement of the minimal clinically important difference (MCID) in patient-reported outcomes (PROs) and satisfaction between cervical spondylotic myelopathy (CSM) patients with and without class III obesity who underwent surgery.
Methods: The authors analyzed patients from the 14 highest-enrolling sites in the prospective Quality Outcomes Database CSM cohort. Patients were dichotomized based on whether or not they were obese (class III, BMI ≥ 35 kg/m2). PROs including visual analog scale (VAS) neck and arm pain, Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA), EQ-5D, and North American Spine Society patient satisfaction scores were collected at baseline and 24 months after cervical spine surgery.
Results: Of the 1141 patients with CSM who underwent surgery, 230 (20.2%) were obese and 911 (79.8%) were not. The 24-month follow-up rate was 87.4% for PROs. Patients who were obese were younger (58.1 ± 12.1 years vs 61.2 ± 11.6 years, p = 0.001), more frequently female (57.4% vs 44.9%, p = 0.001), and African American (22.6% vs 13.4%, p = 0.002) and had a lower education level (high school or less: 49.1% vs 40.8%, p = 0.002) and a higher American Society of Anesthesiologists grade (2.7 ± 0.5 vs 2.5 ± 0.6, p < 0.001). Clinically at baseline, the obese group had worse neck pain (VAS score: 5.7 ± 3.2 vs 5.1 ± 3.3), arm pain (VAS score: 5.4 ± 3.5 vs 4.8 ± 3.5), disability (NDI score: 42.7 ± 20.4 vs 37.4 ± 20.7), quality of life (EQ-5D score: 0.54 ± 0.22 vs 0.56 ± 0.22), and function (mJOA score: 11.6 ± 2.8 vs 12.2 ± 2.8) (all p < 0.05). At the 24-month follow-up, however, there was no difference in the change in PROs between the two groups. Even after accounting for relevant covariates, no significant difference in achievement of MCID and satisfaction was observed between the two groups at 24 months.
Conclusions: Despite the class III obese group having worse baseline clinical presentations, the two cohorts achieved similar rates of satisfaction and MCID in PROs. Class III obesity should not preclude and/or delay surgical management for patients who would otherwise benefit from surgery for CSM.
Keywords: Quality Outcomes Database; cervical spondylotic myelopathy; obesity; patient-reported outcomes; satisfaction.