Patient-reported outcome scores underestimate the impact of major complications in patients undergoing spine surgery for degenerative conditions

Abstract

OBJECTIVE Patient-reported outcomes (PROs) such as the Oswestry Disability Index (ODI) and EuroQol-5D (EQ-5D) are widely used to evaluate treatment outcomes following spine surgery for degenerative conditions. The goal of this study was to use the Charlson Comorbidity Index (CCMI) as a measure of general health status, for comparison with standard PROs. METHODS The authors examined serial CCMI scores, complications, and PROs in 371 patients treated surgically for degenerative lumbar spine conditions who were enrolled in the Quality and Outcomes Database from a single center. The cohort included 152 males (41%) with a mean age of 58.7 years. Patients with no, minor, or major complications were compared at baseline and at 1 year postoperatively. RESULTS Minor complications were observed in 177 patients (48%), and major complications in 34 (9%). There were no significant differences in preoperative ODI, EQ-5D, or CCMI among the 3 groups. At 1 year, there was a significantly greater deterioration in CCMI in the major complication group (1.03) compared with the minor (0.66) and no complication groups (0.44, p < 0.006), but no significant difference in ODI or EQ-5D. CONCLUSIONS Despite equivalent improvements in PROs, patients with major complications actually had greater deterioration in their general health status, as evidenced by worse CCMI scores. Because CCMI is predictive of medical and surgical risk, patients who sustained a major complication now carry a greater likelihood of adverse outcomes with future interventions, including subsequent spine surgery. Although PRO scores are a key metric, they fail to adequately reflect the potential long-term impact of major perioperative complications.