Complication Rates, Operative Times and Hospital Cost Following Anterior Cervical Discectomy and Fusion in Obese versus Non-Obese Patients: A Systematic Review and Meta-analysis

Introduction: Anterior cervical discectomy and fusion (ACDF) is one of the most commonly performed surgical approaches in the US. Obese patients may be at risk of more complications after ACDF and operative times and hospital costs may be adversely affected in this patient group. However, current evidence in the literature is conflicting and no systematic review has been conducted.

Methods: In this PRISMA-compliant systematic review, the MEDLINE database was searched to identify all comparative patients that reported patient and hospital outcomes in obese versus non-obese patients. Primary outcomes included immediate postoperative complication rates, operative (skin-to-skin) times and total hospital costs. Secondary outcomes included estimated blood loss, length of stay, readmission and reoperation rates.

Results: In total, 10 studies encompassing 1,489,746 patients (161,541 obese and 1,328,205 non-obese) fulfilled the inclusion criteria. The mean age range was 50-60.9, 47.7% were males, and the mean follow-up was 26 months. Postoperative dysphagia (Obese 4.3%; Non-Obese 3.6%; OR 1.28; CI 1.25-1.32; I2 0%, P< 0.0001) and DVT/PE rates (Obese 0.3%; Non-Obese 0.2%; OR 1.59; CI 1.02-2.48; I2 92%, P=0.04) were higher in the obese compared to the non-obese group. Rates of postoperative anemia (P=0.9), GU (P=0.2), respiratory (P=0.3), cardiac (P=0.7), wound complications (P=0.4), as well as total complication rates (P=0.4) were comparable among groups. In addition, readmission rates (P=0.97), reoperation rates (P=0.2), operative times (P=0.1), and estimated blood loss (P=0.2) did not differ among groups. Length of stay (Mean Difference 0.28 days; CI 0.11-0.44; I2 %, P=0.001) and total hospital costs (Mean Difference 607.2 $; CI 67-1147.3; I2 70%, P=0.03) (Figure 17) were slightly higher in the obese group and the differences were statistically significant.

Conclusion : In this systematic review, morbidity and complication rates were generally similar between obese and non-obese patients undergoing ACDF. However, there were statistically significant differences in the obese group, including higher rates of dysphagia, DVT/PE, longer hospital stays, and increased total hospital costs. Further research is required to assess the clinical significance of these findings.