Serious dysphagia following anterior cervical discectomy and fusion: long-term incidence in a national cohort.

Background: Although dysphagia is often self-limiting after anterior cervical discectomy and fusion (ACDF), its incidence, risks, and long-term outcomes remain unclear. The present study aimed to analyze dysphagia up to 5 years post-ACDF using a nation-scaled cohort.

Methods: Incidences of permanent dysphagia requiring nasogastric-tube feeding after ACDF were analyzed using three million-sample cohorts derived from the National Health Insurance Research Database of Taiwan. All identified subjects were stratified into four groups (40's, 50's, 60's, and >70) according to their age at operation, and were subsequently followed up for 5 years. The risks of dysphagia were compared between the groups using Kaplan-Meier analysis and Cox regression hazard ratio model.

Results: A total of 2723 patients (>40 years old) who received first-time ACDF surgery were identified from a cohort of three million and followed up for a maximum of 5 years post-operation. The 5-year incidence rates of persistent dysphagia (requiring use of a nasogastric tube) were 6.1, 4.0, 12.0, and 22.8 per 1000 person-years for each age group (40's, 50's, 60's, and 70+ years old, respectively). The overall incidence rate of dysphagia after ACDF was 18.4, 10.9, and 8.9 per 1000 person-years at 3 months, 1 year, and 5 years follow-up, respectively. The incidence rates of dysphagia and use of home care services were highest at 3 months postoperatively in all age groups, but dropped to a stable level after one year post-operation. The risks of dysphagia and the necessity of using home care services were higher (hazard ratio= 2.69 and 4.96) in the elderly group (aged 70 years and over) at all follow-up time points.

Conclusions: The elderly patients had higher risks of short- and long-term severe dysphagia after ACDF. Therefore, although the incidence rates were still low (approximately 2.3%), older patients (aged 70 years and over) should be cautioned for dysphagia requiring a nasogastric tube and home care services if they undergo ACDF.