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.

Hyperlipidemia and statins affect neurological outcome in lumbar spine injury.

The disabling pathophysiologic effects of lipid and neuroprotective effects of statins have recently been demonstrated for acute spinal cord injuries in animal models. This large scale population-based study aimed to investigate the effect hyperlipidemia and the use of statins in patients with lumbar spine injury. The National Health Insurance Research Database of Taiwan was used to identify patients with lumbar spine injury. A total of 2844 patients were grouped into three: no hyperlipidemia, hyperlipidemia using low-dose of statins (≤90 of the defined daily dosage (DDD)), and severe hyperlipidemia using high-dose of statins (>90 DDD). A Cox multiple regression model was used to compare the incidence rates of disability among the three groups. The results showed that patients with hyperlipidemia appeared a higher risk of permanent disability (adjusted HR = 1.38, p = 0.28). In subgroup analysis, patients with severe hyperlipidemia had a higher risk of disability (adjusted HR = 3.1, p < 0.004), whereas hyperlipidemia using low-dose statins had a similar risk of permanently disability (adjusted HR = 0.83, p = 0.661). Hyperlipidemia adversely affected the neurological outcomes of lumbar spinal injury. Statins may have the potential to reverse this higher risk of disability. However, this beneficiary effect of statins only existed in patients using a lower dose (≤90 DDD).

Professional continuous glucose monitoring for the identification of type 1 diabetes mellitus among subjects with insulin therapy.

The identification of type 1 diabetes in diabetic subjects receiving insulin therapy is sometimes difficult. The purpose of this study is to evaluate whether results of professional continuous glucose monitoring can improve the identification of type 1 diabetes.From 2007 to 2012, 119 adults receiving at least twice-daily insulin therapy and professional continuous glucose monitoring were recruited. Type 1 diabetes was diagnosed by endocrinologists according to American Diabetes Association standards, including a very low C-peptide level (<0.35  pg/mL) or the presence of diabetic ketoacidosis. Continuous glucose monitoring was applied for 3 days.Among 119 subjects, 86 were diagnosed with type 1 diabetes. Subjects with type 1 diabetes were younger (33.8 vs 52.3 years old, P < 0.001), had lower body mass index (BMI, 21.95 vs 24.42, P = 0.003), lower serum creatinine (61.77  vs 84.65 µmol/L, P = 0.001), and higher estimated glomerular filtration rate (108.71 vs 76.48 mg/mL/min/1.73m2, P < 0.001) than subjects with type 2 diabetes. Predictive scores for identification of type 1 diabetes were constructed, including age, BMI, average mean amplitude of glucose excursion in days 2 and 3, and the area under the curve of nocturnal hyperglycemic and hypoglycemic states. The area under the receiver operating characteristic curve was 0.90. With the cutoff of 0.58, the sensitivity was 86.7% and the specificity was 80.8%. The good performance was validated by the leave-one-out method (sensitivity 83.3%, specificity 73.1%).Professional continuous glucose monitoring is a useful tool that improves identification of type 1 diabetes among diabetic patients receiving insulin therapy.

Assaying the binding strength of G-quadruplex ligands using single-molecule TPM experiments.

G-quadruplexes are stable secondary structures formed by Hoogsteen base pairing of guanine-rich single-stranded DNA sequences in the presence of monovalent cations (Na(+) or K(+)). Folded G-quadruplex (G4) structures in human telomeres have been proposed as a potential target for cancer therapy. In this study, we used single-molecule tethered particle motion (TPM) experiments to assay the binding strength of possible G4 ligands. We found that individual single-stranded DNA molecules containing the human telomeric sequence d[AGGG(TTAGGG)3] fluctuated between the folded and the unfolded states in a 10 mM Na(+) solution at 37 °C. The durations of folded and unfolded states were single-exponentially distributed, and in return the folding and unfolding rate constants were 1.68 ± 0.01 and 1.63 ± 0.03 (s(-1)), respectively. In the presence of G4 ligands, such as TMPyP4, DODCI, BMVC, and BMVPA, the unfolding rate constant decreased appreciably. In addition, combining the Cu(2+)-induced G4 unfolding and TPM assay, we showed that BMVC and TMPyP4 are better G4 stabilizers than DODCI. The capability of monitoring the fluctuation between the folded and the unfolded state of G4 DNA in real time allows the determination of both kinetic and thermodynamic parameters in a single measurement and offers a simple way to assay binding strength under various conditions.

Mutations altering the interplay between GkDnaC helicase and DNA reveal an insight into helicase unwinding.

Replicative helicases are essential molecular machines that utilize energy derived from NTP hydrolysis to move along nucleic acids and to unwind double-stranded DNA (dsDNA). Our earlier crystal structure of the hexameric helicase from Geobacillus kaustophilus HTA426 (GkDnaC) in complex with single-stranded DNA (ssDNA) suggested several key residues responsible for DNA binding that likely play a role in DNA translocation during the unwinding process. Here, we demonstrated that the unwinding activities of mutants with substitutions at these key residues in GkDnaC are 2-4-fold higher than that of wild-type protein. We also observed the faster unwinding velocities in these mutants using single-molecule experiments. A partial loss in the interaction of helicase with ssDNA leads to an enhancement in helicase efficiency, while their ATPase activities remain unchanged. In strong contrast, adding accessory proteins (DnaG or DnaI) to GkDnaC helicase alters the ATPase, unwinding efficiency and the unwinding velocity of the helicase. It suggests that the unwinding velocity of helicase could be modulated by two different pathways, the efficiency of ATP hydrolysis or protein-DNA interaction.

Epidemiology of acute mountain sickness on Jade Mountain, Taiwan: an annual prospective observational study.

Acute mountain sickness (AMS) is a pathophysiological symptom complex that occurs in high altitude areas. The AMS prevalence is reportedly 28% on Jade Mountain, the highest mountain (3952 m) in Taiwan. We conducted this study owing to the lack of annual epidemiological data on AMS in Taiwan. Between April 2007 and March 2008, 1066 questionnaires were completed by trekkers visiting Paiyun Lodge on Jade Mountain. Information in the questionnaire included demographic data, mountaineering experience, AMS history, and trekking schedule. Weather data were obtained from the Central Weather Bureau of Taiwan. The Lake Louise AMS score was used to record symptoms and diagnose AMS. The chi-square test or the Student t test was used to evaluate associations between variables and AMS. In our study, the AMS prevalence was 36%. It increased significantly at different rates at different locations on the Jade Mountain trail and varied significantly in different months. Rainy weather tended to slightly increase the incidence of AMS. A lower incidence of AMS was correlated with hig-altitude trekking experience or preexposure (p < 0.05), whereas a higher incidence of AMS was correlated with a prior history of AMS (p < 0.05). The trekkers with AMS were significantly younger, ascended faster from their residence to the entrance or to Paiyun Lodge, and ascended slower from the entrance to the Paiyun Lodge (p < 0.05), but the differences lacked clinical significance. No differences in the incidence of AMS based on blood type, gender, or obesity were observed. The most common symptom among all trekkers was headache, followed by difficulty sleeping, fatigue or weakness, gastrointestinal (GI) symptoms, and dizziness or lightheadedness. In conclusion, the AMS prevalence on Jade Mountain was 36%, varied by month, and correlated with trekking experience, preexposure, and a prior history of AMS. The overall presentation of AMS was similar to that on other major world mountains.

A rare case of massive retroperitoneal hemorrhage after bone marrow aspiration alone.

The use of dapsone is increasing even though overdose is rarely reported and physicians must be aware of its toxicity and management. Mortality can occur due to methemoglobinemia and hemolytic anemia. Although activated charcoal and methylene blue are recommended, the use of hemodialysis is reported only in few studies. Literature on the kinetic profile indicates that 50% to 80% of dapsone is protein bound and indicates a possibility to dialyze the unbound form. This study describes a case of deliberate severe dapsone overdose with cyanosis, methemoglobinemia, and hemolytic anemia, which improved after repetitive hemodialysis.

Collision tumor of the stomach: a case report of mixed gastrointestinal stromal tumor and adenocarcinoma.

Collision tumors of the stomach are uncommon. To the best of our knowledge, this is the first case report of gastric collision tumor composed of gastrointestinal stromal tumor (GIST) intermixed with primary adenocarcinoma in the English literature. The adenocarcinoma was determined to be the primary tumor based on histologic features. The tumor cells of the GIST were diffusely and strongly positive for CD34 and CD117, weakly positive for smooth muscle actin (5% of cells), and negative for desmin, S-100 protein, synaptophysin, and cytokeratin. There was no transition between the different components. We hypothesized that the stomach was influenced by the same unknown carcinogen, resulting in a simultaneous proliferation of different cell lines (epithelial and stromal cell). This case represents an example of two independent tumors in a unique one-on-another pattern, namely growth of adenocarcinoma on GIST.