The Impact of Obesity on Patient-Reported Outcomes Following Two-Level Cervical Disc Replacement

Background: Body mass index (BMI) is an important consideration in perioperative evaluation. High BMI is correlated with more comorbidities and poorer operative outcomes; however, there is limited literature on the impact of BMI on patient-reported outcome measures (PROMs) after multilevel cervical disc replacement (CDR) surgery. Objective: The objective was to evaluate the relationship between BMI and PROMs in two-level CDR. Methods: A single-surgeon database was retrospectively reviewed for patients who underwent two-level CDR between August 2017 and October 2024. Patients were stratified as non-obese (BMI < 30 kg/m²; n = 44) or obese (BMI ≥ 30 kg/m²; n = 34). The final analytic cohort included 78 patients. Mean follow-up was 7.65 ± 5.53 months. Multivariable linear and logistic regression models adjusted for age, hypertension, diabetes, and Charlson Comorbidity Index. Patient-reported outcome measures (PROMs) and minimal clinically important difference (MCID) were also analyzed. Statistical analysis was conducted using Stata 18.0 (StataCorp LP, College Station, TX, USA). Results: Obese patients had a higher CCI than non-obese patients (0.90 ± 1.06, 1.87 ± 1.31, p = 0.001). Patient-reported outcomes were collected and analyzed after controlling for hypertension, diabetes, CCI scores, and age. At the final postoperative follow-up, only VR12-MCS differed, with the obese cohort having worse scores (60.7 ± 5.0 versus 53.9 ± 10.2, p = 0.040). MCID achievement rates did not differ between groups across PROMs (p > 0.183 for all). Conclusion: Patients with and without obesity demonstrated comparable early-to-midterm PROM trajectories and MCID achievement following two-level CDR. These findings suggest that obesity was not associated with substantially different patient-reported recovery during the observed follow-up period.