Complications and mortality after lumbar spinal fusion in elderly patients with late stage renal disease

Study Design. Retrospective database review. Objective. To assess complication and mortality rates after lumbar spinal fusion surgery in patients with late stage renal disease. Summary of Background Data. Lumbar spinal fusion surgeries are common in elderly patients who are well-known to have increased comorbidity burden. Elderly patients with severe chronic kidney disease (CKD) represent a population with poorly understood mortality and complication rates after spine surgery. Methods. Medicare data from the PearlDiver Database (2005-2012) was queried for patients who underwent primary 1-2 level posterolateral lumbar spine fusion surgeries. This cohort was divided into two study groups: a cohort with a preexisting diagnosis of late stage renal disease (N = 1654) and a control cohort of all other patients (N = 242,085). The control group was matched to the renal disease cohort by age, sex, and comorbidities. Moreover, 90-day complication rates and 90-day and 1-year mortality were assessed. Results. The renal disease cohort had increased rates of all medical complications (21.3 vs. 14.2%; odds ratio, OR, 1.64; 95% confidence intervals, CI, 1.44-1.85; P < 0.0001). Increased rates of infection (4.4 vs. 1.8%; OR 2.43; 95% CI 1.87-3.16; P < 0.0001) and procedure-day blood transfusions (20.7 vs. 14.7%; OR 1.51; 95% CI 1.33-1.72; P < 0.0001) were also observed in the renal disease cohort. Both 90-day (1.1 vs. 0.2%; OR 5.05; 95% CI 2.90-8.77; P < 0.0001) and 1-year mortality (1.9 vs. 0.7%; OR 2.77; 95% CI 1.87-4.11; P < 0.0001) were significantly higher in the renal disease group compared with the control group. Conclusion. Elderly patients with late-stage renal disease treated with 1-2 level posterolateral lumbar fusion have 1.6 times increased odds of experiencing a major medical complication within 3 months of surgery and 2.8 times increased odds of 1-year mortality when compared with matched controls.