Do Patients with high ASA Grades Benefit from CSM Surgery?: A Report From the Quality Outcomes Database.

Abstract

Analysis of prospectively collected data. To assess if systemic illness severity affects cervical spondylotic myelopathy (CSM) surgery outcomes. It remains unclear if CSM patients with poor physical status/severe systemic illness benefit as much from surgery as those in good condition. Using the Quality Outcomes Database CSM cohort and the American Association of Anesthesiology (ASA) grade as a surrogate for illness burden, we compared patients with (ASA 3-4) and without (ASA 1-2) severe systemic illness, including rates of readmission and 24-month minimal clinically important differences (MCID) achievement for patient-reported outcomes (PROs)-numerical rating score (NRS) arm and neck pain, neck pain-related disability (NDI), and quality of life (EQ-5D). Of 1141 CSM patients, 1062 had ASA grades recorded. Of these 1062 patients, 70.2% had a 2-year follow-up for mJOA, and 81%-84% had a follow-up for NRS arm and neck, NDI, and EQ-5D. Five hundred twenty-one patients (49.1%) had mild (ASA 1-2) and 541 (50.9%) had severe systemic illness (ASA 3-4). The severe disease cohort was older (63.3±11.0 vs. 57.4±11.7), had higher BMI (31.4±7.0 vs. 28.9±5.6), had more comorbidities (diabetes, coronary artery disease, depression), and had less independent ambulation (71.3% vs. 90.6%) (P<0.05). At baseline, severe disease patients had worse NRS arm (5.2±3.5 vs. 4.7±3.4) and neck (5.5±3.2 vs. 5.1±3.3) pain, NDI (40.5±20.1 vs. 36.8±21.0), and EQ-5D (0.53±0.22 vs. 0.59±0.22) scores (P<0.05). Perioperatively, the severe disease cohort had longer hospitalizations (2.4±2.6 vs. 1.7±2.0 days) and increased nonhome discharges (17% vs. 5%) (P<0.05).The severe disease cohort had higher 90-day readmissions (7.6% vs. 2.5%), including surgery-related (3.7% vs. 1.5%) and non-surgery-related reasons (3.9% vs. 1.0%) (P<0.05). On multivariate analysis, increased ASA grade was significantly associated with 90-day readmissions (OR: 2.55 per 1-grade increase, 95% CI: 1.38-4.83). However, both severe and mild disease cohorts had similarly high rates of achieving 2-year MCID for mJOA (67.5% vs. 66.0%), NRS arm (72.0% vs. 74.1%), neck (69.5% vs. 69.4%) pain, NDI (63.1% vs. 68.1%), and EQ-5D (67.9% vs. 66.9%) (P>0.05). Patients with severe systemic illness (higher ASA) have worse baseline PROs and higher 90-day readmissions. However, they achieve similar MCID rates for mJOA and all measured PROs 2 years postoperatively.