Effects of Medical Comorbidities on the Surgical Outcomes of Deep Brain Stimulation for Parkinson Disease: A Retrospective, Single-Institution Study

Objective: Advancing age and greater number of medical comorbidities are well-known risk factors for higher rates of surgical complications and undesirable outcomes. We sought to determine the risk of increasing medical comorbidities on surgical outcomes for patients with Parkinson disease undergoing deep brain stimulation (DBS) surgery.

Methods: We retrospectively reviewed 107 consecutive patients who underwent DBS for Parkinson disease at Ochsner Medical Center in 2008-2018. Patients were stratified into 3 groups based on Elixhauser comorbidity index (ECI) at the time of surgery: 0, 1, or ≥2. Outcome measures were changes in Unified Parkinson's Disease Rating Scale III scores, changes in medications, and surgical complications. Analysis of variance, paired t test, and nonparametric equivalents were used for statistical analysis.

Results: Of patients, 31 (29.0%) had ECI score 0, 44 (41.1%) had ECI score 1, and 32 (29.9%) had ECI score ≥2. For all groups, Unified Parkinson's Disease Rating Scale III scores decreased significantly postoperatively (P = 0.0014, P < 0.0001, P < 0.0001). All groups had a reduction in mean levodopa equivalent daily dose after surgery; however, only the group with ≥2 comorbidities achieved statistical significance (P = 0.0026). The rate of postoperative complications was significantly correlated with comorbidity score on univariate logistic regression analysis (P = 0.0425).

Conclusions: Our findings indicate that DBS is efficacious in patients with multiple medical comorbidities. However, patients with ≥1 medical comorbidities may be more likely to have complications. The most common observed complication was wound infection. Patients with medical comorbidities may still benefit significantly from DBS when performed at experienced centers.