Comparing risk factors for postoperative dysphagia following single- or multilevel anterior cervical spine surgery

OBJECTIVE: Studies have shown that patients undergoing multilevel cervical operations are at greater risk for postoperative dysphagia compared to those who undergo single-level operations. This study aimed to compare risk factors for postoperative dysphagia in patients undergoing single- versus multilevel anterior cervical surgery. METHODS: A prospectively collected quality registry was retrospectively reviewed to identify candidates who underwent anterior cervical procedures. Procedures involving 1 disc space were categorized as single level, and procedures involving ≥ 2 consecutive disc spaces were categorized as multilevel. Dysphagia rates were determined using Eating Assessment Tool-10 (EAT-10) scores. Univariate and multivariate analyses were performed to identify significant risk factors for postoperative dysphagia within 12 months of surgery. RESULTS: Of 1705 patients who met the inclusion criteria, 804 (47.2%) underwent single-level and 901 (52.8%) underwent multilevel procedures. Both groups had similar rates of baseline dysphagia (14% vs 14%, p > 0.9). Multilevel patients had significantly higher rates of dysphagia at 1 month (64% vs 54%, p = 0.001), 3 months (32% vs 25%, p = 0.004), and 12 months (29% vs 21%, p = 0.004) postoperatively. Multivariable regression revealed that for single-level surgery, Black race (OR 2.40, p = 0.021), higher American Society of Anesthesiologists (ASA) class (OR 1.45, p = 0.018), symptom duration for more than 12 months (OR 1.66, p = 0.043), baseline dysphagia (OR 4.53, p < 0.001), diabetes (OR 1.76, p = 0.014), peripheral vascular disease (OR 3.74, p = 0.049), and operations involving C3-4 (OR 2.25, p = 0.004) were independent predictors of postoperative dysphagia within 12 months of surgery. For multilevel procedures, baseline dysphagia (OR 7.31, p < 0.001), diabetes (OR 1.61, p = 0.022), and operations involving C3-4 (OR 1.85, p = 0.011) or C4-5 (OR 1.64, p = 0.010) were independent predictors of postoperative dysphagia, while listhesis (OR 0.63, p = 0.042) was an independent predictor of no postoperative dysphagia. CONCLUSIONS: Patients undergoing single-level cervical procedures are at lower risk for postoperative dysphagia. Preexisting dysphagia, diabetes, and the inclusion of upper cervical levels independently contribute to dysphagia risk following both single-level and multilevel surgical procedures. Black race, ASA class, prolonged preoperative symptom duration, and peripheral vascular disease are associated with dysphagia risk particularly in single-level procedures, while listhesis predicts lower dysphagia risk specifically in multilevel surgical procedures. These results can aid patient counseling by providing stratified risk factors for postoperative dysphagia.