Incidence and Causes of Death after Cervical or Thoracolumbar Adult Spinal Deformity Surgery

STUDY DESIGN: Prospective multicenter study. OBJECTIVE: To determine the incidence of all-cause mortality after adult spinal deformity surgery. SUMMARY OF BACKGROUND DATA: Patients undergoing adult spinal deformity surgery are often frail and the procedures are invasive. The incidence of all-cause mortality among patients undergoing cervical or thoracolumbar deformity surgery is unclear. METHODS: Using 2 prospective, multicenter databases, we identified patients who underwent surgery for cervical deformity surgery from 2013-2020 (n=169) or thoracolumbar deformity from 2008-2020 (n=1507). Mortality incidence density was calculated as follows: 100 × (number of deaths) / (sum of total years of follow-up for all patients). RESULTS: Of 169 participants in the cervical group (mean±standard deviation age, 61±10 y), death occurred in 19 (11%). The mean time to death was 25±19 months. Mortality incidence density was 4.4 deaths per 100 person-years. The 30-day mortality rate was 0.6% (1/169) and 90-day mortality rate was 1.2% (2/169). The 3 most common causes of death were arrhythmia/cardiac arrest (16%), congestive heart failure (11%), and pneumonia (11%). There were no intraoperative deaths. Of 1507 participants in the thoracolumbar group (mean±standard deviation age, 61±14 y), death occurred in 53 (3.5%). The mean time to death was 32.5±21.5 months. Mean duration of follow-up was 1.8±1.5 years. The mortality incidence density was 0.8 deaths per 100 person-years. The 30-day mortality rate was 0.1% (1/1507) and 90-day mortality rate was 0.3% (4/1507). The 3 most common causes of death were non-spine malignancy (13%), pneumonia (9%), and arrhythmia/cardiac arrest (6%). CONCLUSIONS: The number of deaths per year was higher among cervical deformity patients (4.4 per 100 person-years) than among thoracolumbar deformity patients (0.8 per 100 person-years). Pneumonia and arrhythmia/cardiac arrest were among the most common causes of death in both groups. LEVEL OF EVIDENCE: III.