Increased Age at Time of Spinal Fusion Does Not Increase Risk of Adverse Outcomes: A Propensity Score-Matched Multicenter Retrospective Cohort Study.

BACKGROUND: The US population is aging, with the number of individuals aged 85 or older expected to triple by 2060. As such, spine surgeons are operating on an increasing number of elderly patients. This propensity score-matched retrospective analysis aimed to determine whether 30-day postoperative outcomes from spinal fusion surgery differ between super-elderly patients (aged ≥85 years) and younger patients (≤65 years). METHODS: Patients in the 2015 to 2023 National Surgical Quality Improvement Program datasets were included if they were treated by an orthopedic or neurological surgeon with a primary Current Procedural Terminology code corresponding to spinal fusion at any level. Patients were separated into a younger cohort (≤65 years) and a super-elderly cohort (≥85 years). Propensity score matching was performed to balance demographics, comorbidities, surgical indications, and specific surgical procedures. Univariate statistical analysis followed by false-discovery rate correction was performed using Python 3.10.16. RESULTS: Following matching, there were 1298 patients in each cohort. There was a 2.6% higher rate of pneumonia (P < 0.01), a 1.8% greater risk of reintubation (P < 0.01), a 1.2% increase in failure to wean from the ventilator after 48 hours (P < 0.01), a 1.9% higher rate of urinary tract infection (P < 0.01), a 1.2% higher risk of myocardial infarction (P < 0.01), and a 1.2% increase in mortality rate (P < 0.01) in the super-elderly compared with younger patients. Older patients were also more likely to be discharged to a skilled care facility (P < 0.01) and had a shorter operative duration (P < 0.01) and longer hospital stay (P < 0.01) relative to younger patients. CONCLUSIONS: Although we identified statistically significant increases in the risk of several adverse outcomes in the super-elderly population, the magnitude of these differences ranged from 1.2% to 2.6%, implying minimal clinical significance. Considering the increased risk of medical complications independent of surgical intervention in the super-elderly population, the minor increase in the risk of complications observed in this study can be considered acceptable, suggesting that advanced age alone is not a contraindication to surgery. CLINICAL RELEVANCE: The results of this study provide insights into the safety of spinal arthrodesis in the growing super-elderly population.