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.

Characteristics of Non-Emergent Visits in Emergency Departments: Profiles and Longitudinal Pattern Changes in Taiwan, 2000-2010.

An increasing number of emergency department (ED) visits have posed a challenge to health systems in many countries, but an understanding of non-emergent ED visits has remained limited and contentious. This retrospective study analyzed ED visits using three representative cohorts from routine data to explore the profiles and longitudinal pattern changes of non-emergent ED visits in Taiwan. Systematic-, personal-, and ED visit-level data were analyzed using a logistic regression model. Average marginal effects were calculated to compare the effects of each factor. The annual ED visit rate increased up to 261.3 per 1000 population in 2010, and a significant one-third of visits were considered as non-emergent. The rapidly growing utilization of ED visits underwent a watershed change after cost-sharing payments between patients and medical institutions were increased in 2005. In addition to cohort effects resulting from cost-sharing payment changes, all factors were significantly associated with non-emergent ED visits with different levels of impact. We concluded that non-emergent ED visits were associated with multifaceted factors, but the change to cost-sharing payment, being female, younger age, and geographical residence were the most predictive factors. This information would enhance the implementation of evidence-based strategies to optimize ED use.

Tetanus Vaccination and Extra-Immunization among Adult Populations: Eight-Year Follow Up Cohort Study of 771,443 Adults in Taiwan, 2006⁻2013.

Under-and extra-immunization of tetanus boosters are important issues to consider in reducing the burden of vaccine-preventable disease in adults. The present study aimed to analyze the trend of vaccination coverage (VC) and risk factors associated with extra-immunization of tetanus during an 8-year period using a national-scale cohort database. Taiwan's one-million representative research database, the Longitudinal Health Insurance Database (LHID2005) was used. A total of 771,443 adults aged between 20 and 79 years were enrolled and followed from 1 January 2006 to 31 December 2013. VC at the beginning was as low as 35.1%, declining gradually and dropping to 33.9% at the end of follow-up. While a total of 303,480 tetanus boosters were used during the study period, more than half (55.5%) of these boosters were considered as extra-immunized. Both individual characteristics and visit characteristics were strongly associated with extra-immunization. Males, young and older adults, and those with a higher number of comorbidities were more likely to receive extra-immunization boosters, especially when they had more severe symptoms, visited an emergency room, or visited a hospital with lower accreditation levels located in a less urbanized area. This information could enhance implementation of evidence-based programs for tetanus boosters.

Increased Risk of Stroke in Patients of Concussion: A Nationwide Cohort Study.

Long-term morbidities can develop after traumatic brain injury (TBI). Some studies have suggested that the risk of stroke is higher after TBI, but the association between concussion and stroke remains unclear. Using a national cohort, the authors analyzed the incidence of both hemorrhagic and ischemic strokes in patients with previous concussion. A representative cohort of approximately one million people was followed up for four years. Patients with new-onset concussion were identified (n = 13,652) as the concussion group. Subsequently, the incidence rates of later stroke events in the concussion group were compared to a sex-, age- and propensity score-matched comparison group (n = 13,652). The overall incidence rate of stroke in the concussion group was higher than that of the comparison group (9.63 versus 6.52 per 1000 person-years, p < 0.001). Significantly higher stroke risk was observed in the concussion group than in the comparison group (crude hazard ratio 1.48, p < 0.001; adjusted HR 1.65, p < 0.001). In the concussion group, the cumulative incidence rates of both ischemic stroke and hemorrhagic stroke were higher than those of the comparison group (8.9% vs. 5.8% and 2.7% vs. 1.6%, respectively, both p < 0.001). Concussion is an independent risk factor for both ischemic and hemorrhagic strokes. Prevention and monitoring strategies of stroke are therefore suggested for patients who have experienced concussion.

Lower Risk of Stroke after Deformity Surgery: Long Term Benefit Demonstrated by a National Cohort Study.

OBJECTIVES: This study aimed to investigate the long-term risk of stroke in adult patients with spinal deformity. Specifically, the study addressed the possible protective effect of surgery for spinal deformity against stroke. METHODS: Using the National Health Insurance Research Database (NHIRD), a monopolistic national database in Taiwan, this retrospective cohort study analyzed the incidence of stroke in patients with adult spinal deformity (ASD) in a 11-year period. A total of 13,503 patients, between 55 and 75 years old, were identified for the diagnosis of ASD. The patients were grouped into two: the surgical group (n = 10,439) who received spinal fusion surgery, and the control group (n = 2124) who received other medical treatment. The incidence rates of all subsequent cerebrovascular accidents, including ischemic and hemorrhagic strokes, were calculated. Hazard ratios for stroke were calculated use a full cohort and a propensity score matched cohort. Adjustments for co-morbidities that may predispose to stroke, including hypertension, diabetes mellitus, arrhythmia and coronary heart disease were conducted. Kaplan-Meier and Cox regression analyses were performed to compare the risk of stroke between the two groups. RESULTS: During the total observation period of 50,450 person-years, the incidence rate of stroke in the surgical group (15.55 per 1000 person-years) was significantly lower than that of the control group (20.89 per 1000 person-years, p < 0.001). Stroke was more likely to occur in the control group than in the surgical group (crude hazard ratio 1.34, p < 0.001; adjusted HR 1.28, p < 0.001, by a propensity score matched model). CONCLUSIONS: In this national cohort of more than 13,000 ASD patients covering 10 years, stroke was approximately 25% less likely to happen in patients who underwent spinal fusion surgery than those who received medical management. Therefore, spinal fusion surgery may provide a protective effect against stroke in adult patients with spinal deformity.