Nationwide Population-based Retrospective Study Research Articles

Prevalence of age-related macular degeneration among optometric telemedicine users in Spain: a retrospective nationwide population-based study

To evaluate the prevalence of AMD among optometric telemedicine users in Spain and to identify risk factors. Retrospective analysis of a nationwide database conducted on subjects attending to optometry centers, between January 2013 and December 2019. Fundus photographs were performed by optometrists, using non-mydriatic cameras, and evaluated by a group of 12 retina specialists. Among the 119,877 subjects included, the overall prevalence of AMD was 7.6%. The prevalence of early, intermediate, and advanced AMD was 2.9%, 2.7%, and 2.0%, respectively. Of the 9129 AMD subjects, 1161 (12.7%) had geographic atrophy, and 1089 (11.9%) had neovascular AMD, either scar (4.5%) or exudative (7.4%). There was a significant association between AMD and age (per year older, adjusted odds ratio, OR 1.116; 95% CI 1.114 to 1.119, p<0.0001). Women had higher prevalence (adjusted OR 1.17; 95% CI 1.12 to 1.23, p<0.0001). Every diopter (spherical equivalent) of progress toward hyperopia was associated with a significant increase in early AMD prevalence (adjusted OR 1.02, 95 CI 1.01 to 1.04, p=0.0074). Presence of diabetes was associated with a lower AMD prevalence (p<0.0001). The prevalence of AMD (any eye and any severity) was 7.6%, with a prevalence of advanced AMD of 2.0%. Older age and women were significantly associated with a higher prevalence of AMD, whereas myopia and presence of diabetes were associated with significantly lower odds of any AMD.

Pediatric Sedation in the Emergency Department: Trends from a Nationwide Population-based Study in Korea, 2007-2018.

BackgroundPediatric sedation in the emergency department (ED) is widely performed in Korea; thus exploring the trends of its use is necessary. This study aimed to investigate the characteristics of patients and sedatives use in the ED and verify their changes over recent years.MethodsA nationwide population-based retrospective study was conducted including pediatric patients aged ≤ 15 years who received sedative medication in the ED and were discharged during 2007–2018, using the Korean Health Insurance Review and Assessment Service database. Patient characteristics (age, sex, level of ED, and diagnosis) and type of sedative used were analyzed.ResultsSedation was performed in total 468,221 visits during 2007–2018 (399,320 visits, at least 3.8% of overall ED visits during 2009–2018). Among these, 71.0% were children aged 1–3 years and 93.5% were sedated to support diagnosis of injury. An increase in total sedation was observed in patients aged 4–6 years during the study period (from 13.8% to 21.8%). A gradual decrease in the use of chloral hydrate (CH) compared with an increase in ketamine use was observed (CH, from 70.6% to 28.6%; ketamine, from 23.8% to 60.7%). Therefore, ketamine was the most used sedative since 2014. The most frequently used sedatives over the study period differed according to age groups (CH in <1 year and 1–3 years; ketamine in 4–6 years and 7–10 years; and midazolam in 11–15 years).ConclusionsThe characteristics of patients related to sedatives use in the ED have changed over time. These changes should be considered in the development of future Korean guidelines regarding pediatric sedation in the ED.

Comment on Katsarelias, D., et al. "The Effect of Beta-Adrenergic Blocking Agents in Cutaneous Melanoma-A Nation-Wide Swedish Population-Based Retrospective Register Study" Cancers 2020, 12, 3228.

We read the paper by Katsarelias et al. with great interest, regarding the effect of beta-adrenergic blocking agents on cutaneous melanoma [1]. However, the study presents some methodology biases that do not allow us to support the authors' conclusions. The paper suffers from the unification and evaluation of multiple registries, which do not provide essential data for any of the targets for research. Unlike studies in the literature [...].

Reply to Comment on Katsarelias, D., et al. "The Effect of Beta-Adrenergic Blocking Agents in Cutaneous Melanoma-A Nation-Wide Swedish Population-Based Retrospective Register Study." Cancers 2020, 12, 3228.

We thank De Giorgi et al for their interest in our study, and for raising important and relevant questions [...].

The Effect of Beta-Adrenergic Blocking Agents in Cutaneous Melanoma-A Nation-Wide Swedish Population-Based Retrospective Register Study.

Simple SummaryPrevious smaller studies have showed that a common heart medication, beta-blockers, potentially could reduce the risk of recurrence in patients with malignant melanoma and thereby increase survival. By combining different Swedish population-based registries, a total of 12,738 patients with melanoma were identified. Out of these patients 3702 had been prescribed beta-blockers and the remaining 9036 patients served as the control group. In a statistical analysis adjusting for known risk factors there was no effect of beta-blockers in reducing the risk of dying from melanoma. In conclusion, this population-based registry study could not verify the hypothesis that the use of beta blockers would improve survival in patients with melanoma.Previous studies have demonstrated an anti-tumoral effect of beta-adrenergic blocking agents on cutaneous melanoma (CM). The aim of this study was to investigate if beta-adrenergic blocking agents have an impact on survival in Swedish patients with melanoma. A population-based retrospective registry study including all patients diagnosed with a primary invasive melanoma between 2009 and 2013 was performed. Data from the Swedish Melanoma Register were linked to the Swedish Prescribed Drug Registry and the Swedish Cause of Death Register. Cox regression analyses including competing risk assessments were performed. There were 12,738 patients included, out of which 3702 were exposed to beta-blockers vs. 9036 non-exposed patients. Age, male sex, Breslow thickness, ulceration, and nodal status were independent negative prognostic factors for melanoma-specific survival (MSS). Adding beta-blockers to the analysis did not add any prognostic value to the model (HR 1.00, p = 0.98), neither when adjusting for competing risks (HR 0.97, p = 0.61). When specifically analyzing the use of non-selective beta-blockers, the results were still without statistical significance (HR 0.76, p = 0.21). In conclusion, this population-based registry study could not verify that the use of beta-adrenergic blocking agents improve survival in patients with melanoma.

Clinical Characteristics and Risk Factors for Fatality and Severity in Patients with Coronavirus Disease in Korea: A Nationwide Population-Based Retrospective Study Using the Korean Health Insurance Review and Assessment Service (HIRA) Database.

Background: We aimed to investigate the clinical characteristics and risk factors for fatality and severity in these patients. Methods: In this nationwide population-based retrospective study, we investigated the data of 7339 laboratory-confirmed COVID-19 patients, aged ≥ 18 years, using the Korean Health Insurance Review and Assessment Service (HIRA) database. Comorbidities and medications used were identified using HIRA codes, and severe COVID-19 was defined as that requiring oxygen therapy, mechanical ventilator, cardiopulmonary resuscitation, or extracorporeal membrane oxygenation. The outcomes were death due to COVID-19 and COVID-19 severity. Results: Mean patient age was 47.1 years; 2970 (40.1%) patients were male. Lopinavir/ritonavir, hydroxychloroquine, antibiotics, ribavirin, oseltamivir, and interferon were administered to 35.8%, 28.4%, 38.1%, 0.1%, 0.3%, and 0.9% of patients, respectively. After adjusting for confounding factors, diabetes mellitus, chronic kidney disease, previous history of pneumonia, aging, and male were significantly associated with increased risk of death and severe disease. No medication was associated with a reduced risk of fatality and disease severity. Conclusions: We found several risk factors for fatality and severity in COVID-19 patients. As the drugs currently used for COVID-19 treatment have not shown significant efficacy, all efforts should be made to develop effective therapeutic modalities for COVID-19.

The harm of anticoagulation in patients with low-risk by CHADS2 and reclassified as high-risk by CHA2DS2VASc: inferences from TRAF cohort.

There is a gap in the knowledge concerning oral anticoagulation (OAC) in atrial fibrillation (AF) patients with a non-high risk of stroke. CHA2DS2VASc and CHADS2 scores generated imprecise risk estimates for low risk patients. We aimed to assess OAC in patients with low risk by CHADS2 and reclassified as high-risk by CHA2DS2VASc. In this study, retrospective nationwide population-based study, data were obtained from the Turkish claims and utilization management system. Patients with non-valvular AF (n=451,113) between 2007 and 2012 sub-divided into those with a CHA2DS2VASc≥1 and CHADS2=0 (n=41,273) who were off-warfarin (n=29,448) and on-warfarin (n=11,825). Stroke and systemic embolism, major bleeding, all-cause mortality, net clinical benefit (NCB) and ultimate NCB (UNCB) were assessed. Of the total cohort (mean age 66.1 ± 14.1 years, 56.1% female), CHA2DS2VASc improved the net reclassification index of observed 5-year composite thromboembolic endpoint by 6.9% (p<0.05). CHA2DS2VASc reclassified 9.7% low risk patients as high risk. Among reclassified-high-risk category (patients with a CHA2DS2VASc score of ≥1 and CHADS2 score of 0), major bleeding for that prescribed warfarin was 3% and higher than the rate of thromboembolism among those off-warfarin. NCB (-0.035) and UNCB (-0.021) were negative. Death and hospitalization at 1 year were significantly higher for on-warfarin group. Clinical outcomes, net clinical benefit indices are negative; rates of death and hospitalization were significantly higher for OAC in reclassified category. This emphasizes the importance of greater attention to balancing the risks and benefits of OAC in patients with low risk by CHADS2 and reclassified as high-risk by CHA2DS2VASc.

Increased risk of cancer in patients with retinal vein occlusion: a 12-year nationwide cohort study

AimsTo investigate the association between incident retinal vein occlusion (RVO) and the subsequent development of cancer.MethodsIn this nationwide population-based retrospective study using 2002–2013 National Health Insurance Service database which covers...

Preradiation tooth extraction and jaw osteoradionecrosis: Nationwide population-based retrospective study in Taiwan.

Radiotherapy (RT) for head and neck cancer (HNC) within 7days of tooth extraction is contraindicated because it may increase the risk of osteoradionecrosis of the jaw (ORNJ). However, delayed RT could compromise survival in patients with HNC. By using a national healthcare database, we reviewed the contraindications and analysed other risk factors for ORNJ. A retrospective cohort study. By using Taiwan's National Health Insurance Research Database, 5,062 HNC patients with at least one tooth extraction 1-21days before the first RT day (index day) and without any extractions during or after RT from 2000 to 2013 were included. The patients were divided into two groups according to the time of tooth extraction before the index day: 1-7days and 8-21days. Taiwanese patients with head and neck cancer. Univariate and multivariate Cox proportional hazard regression models were used to evaluate the risk factors of ORNJ. The overall incidence of ORNJ in the included patients was 1.03% (mean follow-up duration, 4.07±3.01years; range, 1.00-13.99years). Tooth extraction within 7days before RT was not associated with increased ORNJ risk (hazard ratio [HR] =0.734; P=.312). Significant risk factors for ORNJ included oral cancer (adjusted HR=3.961), tumour excision surgery within 3months before RT (adjusted HR=3.488) and mandibulectomy within 3months before RT (adjusted HR=5.985; all P<.001). In a mean follow-up of 4years, tooth extraction within 7days before RT for HNC treatment did not increase the ORNJ risk compared with tooth extraction 7-21days before RT.

Epidemiology and comorbidities of adult multiple sclerosis and neuromyelitis optica in Taiwan, 2001–2015

BackgroundThe epidemiology of multiple sclerosis (MS) and neuromyelitis optica (NMO) remains to be clarified or updated in many parts of Asia. This study aims to investigate the epidemiology and comorbidities of MS and NMO during 2001–2015 in Taiwan. MethodsWe conducted a retrospective nationwide population-based study using data from Taiwan's National Health Insurance Research Database. Cases of MS and NMO aged 20 years or above during 2001–2015 were enrolled. The incidence, prevalence, demographic features, and comorbidities were investigated. ResultsWe identified 4627 MS and 861 NMO incident cases aged 20 or above during 2003–2015. The incidence of MS was relatively stationary, while that of NMO apparently rose steeply during the study period. The age-standardized incidence rate of MS and NMO in 2015 were 1.34 and 0.61 per 100,000 person-years, respectively. The age-standardized prevalence rate of MS and NMO in 2015 were 6.69 and 1.47 per 100,000 persons, respectively. The female preponderance was evident for both MS and NMO. Except for diabetes mellitus, the most common autoimmune comorbidities for MS and NMO were Sjogren syndrome and systemic sclerosis, and Sjogren syndrome and systemic lupus erythematosus, respectively. ConclusionsTaiwan has transitioned from low- to medium-risk zone during 2001–2015 in terms of MS prevalence, although its incidence remained stationary. The apparent upsurge of NMO over the period probably reflects increased awareness of this clinical entity. Comorbid autoimmune disorders were relatively common, and overlapping but differential autoimmune comorbidity profiles were noted for MS and NMO.

Osteoporosis and the risk of temporomandibular disorder in chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a major cause of chronic morbidity and mortality worldwide. The coexistence of COPD and temporomandibular disorder (TMD) has been noted, and dysfunctional mastication resulting from TMD can worsen individuals' nutritional status. This association between COPD and TMD has been rarely discussed in previous studies. Therefore, this study aimed to determine whether osteoporosis increases the risk of TMD in COPD and whether anti-osteoporosis medications can prevent TMD. This retrospective nationwide population-based study utilized the Taiwan National Health Insurance Research Database. We enrolled 52,652 COPD patients between 2000 and 2015: 13,163 with osteoporosis and 39,489 without osteoporosis. Groups of COPD patients with and without osteoporosis were age- and sex-matched. A multivariable Cox proportional hazards regression model was used to evaluate the risk of TMD development in COPD patients with and without osteoporosis over 15years. There was a higher risk of TMD occurrence in COPD patients with osteoporosis than in those without osteoporosis (adjusted hazard ratio 2.564, P < 0.001) after adjusting for demographic variables and associative comorbidities. Osteoporosis, hypertension, vertebral compression fracture, and nonpsychotic mental disorders were risk factors contributing to TMD development in patients with COPD. Anti-osteoporosis medications were associated with the prevention of TMD development concomitant with osteoporosis and COPD (adjusted hazard ratio 0.617, P = 0.004). Patients with COPD and osteoporosis are at a higher risk of developing TMD, and anti-osteoporosis medications can prevent the development of TMD in this context.

Twelve-year incidence of retinal vein occlusion and its trend in Korea.

To estimate the 12-year incidence and trends of clinically diagnosed retinal vein occlusion (RVO) in Korea. This is a nationwide population-based retrospective study using the Korean national health claims database from 2002 to 2015. The study consisted of the entire Korean population based on the 2015 Census of Population. We identified patients with incident RVO in 2004-2015. We estimated the crude incidence rates and age- and sex-standardized incidence rates in each 12-year study period. To determine the trend, we also performed joinpoint regression analyses. We identified 240,495 incident RVO cases. The average incidence rate was 48.09 (95% confidence interval [CI], 47.92-48.27). Women showed a 1.24 times higher incidence rate (53.18 [95% CI, 52.92-53.44]) compared with men (42.78 [95% CI, 42.55-43.02]), while, among patients aged less than 50years and those aged 80years or over, men showed higher incidence rates than did women. The highest incidence of 193.56 (95% CI, 191.06-196.06) was observed in the age group of 75 to 79years. The joinpoint analysis showed an increasing trend of RVO incidence among patients at the age of 70years and older (annual percentage change, 2.1; 95% CI, 0.2-4.0; p < 0.01). RVO is a disease of the elderly that peaks in the late 70s and occurs more in women than in men. In Korea, RVO incidence increased from 2004 to 2015 among the population aged 70years or older, while among those aged less than 70years, no trend was observed in RVO incidence rates.

Association between hypertensive pregnancy disorders and future risk of stroke in Taiwan: a Nationwide population-based retrospective case-control study

BackgroundThe incidence of female stroke has increased gradually and has begun occurring at a younger age in recent years. Given that women live longer than men, stroke would cause more negative and longer-term impacts on the rest of the lives of women. There are few related studies on Asian women. We aimed to evaluate stroke risk in Asian women following hypertensive pregnancy disorders.MethodsUsing the Taiwan National Health Insurance database, we designed a retrospective study that included pregnant women between 2000 and 2013. We selected an age-matched control group of women without hypertensive pregnancy disorders at a 1:3 ratio. The endpoint was any episode of stroke; otherwise, the patients were tracked until December 31, 2013. After the index date until the end of 2013, Cox proportional hazards analysis was used to compare the risk of incident stroke. The risk factors for stroke were determined using Cox proportional regression to calculate the hazard ratio (HR) compared with the control group.ResultsDuring the follow-up period, the Kaplan-Meier analysis indicated that patients with hypertensive pregnancy disorders had a significantly higher risk of developing stroke than did patients without hypertensive pregnancy disorders (log-rank test P < 0.001). Multivariate Cox regression analysis demonstrated that the case group had a 2.134-fold increased risk of stroke (HR = 2.134; 95% CI = 1.817–2.505; P < 0.001).ConclusionOur study provided evidence of an increased risk of stroke in patients with hypertensive pregnancy disorders. Compared with those without such disorders, the patients who had experienced the disorders had a 2.134-fold (P < 0.001) higher risk of developing stroke in the future.

Magnesium oxide and hip fracture in the elderly: a population-based retrospective cohort analysis.

The purpose of this study was to investigate the association between MgO use and hip fracture risk in the elderly (age > 65years). This nationwide population-based retrospective study was conducted from 1996 to 2013. Individuals with (n = 26,069) and without (n = 26,069) MgO use were enrolled after propensity score matching. Primary outcome was a hip fracture. After adjusting for age, sex, comorbidities, and medications, multivariate Cox proportional hazards regression models were used to calculate incidences and risk of hip fracture [hazard ratio (HR)]. During the mean follow-up duration of 4.8years in the MgO cohort and 5.7years in the non-MgO cohort, respectively 1547 and 1107 cases developed a hip fracture. MgO use was identified as a risk factor for hip fracture in both univariate [crude HR, 1.68; 95% confidence interval (CI), 1.55-1.81; p < 0.001] and multivariate [adjusted HR (aHR), 1.66; 95% CI, 1.54-1.80; p < 0.001] Cox proportional hazards regression models. The cumulative incidence of hip fracture was significantly higher in the MgO cohort than in the non-MgO cohort (1.23 per 100 person-years vs. 0.74 per 100 person-years, logrank test, p < 0.001). MgO use is an independent risk factor for hip fracture in the elderly.

Epidemiology of pediatric multiple sclerosis, neuromyelitis optica, and optic neuritis in Taiwan.

The epidemiology of pediatric acquired demyelinating disorders remains to be clarified in many parts of Asia. We carry out this study to depict the epidemiology of pediatric multiple sclerosis (MS), neuromyelitis optica (NMO), and optic neuritis (ON) in Taiwan. We conducted a retrospective nationwide population-based study using data from Taiwan's National Health Insurance Research Database. Prevalent cases of pediatric MS and NMO during 2001-2015, and incident cases of pediatric MS, NMO, and ON during 2003-2015 were identified. The demographic features and comorbidities were investigated. We identified 403 MS, 42 NMO, and 1496 ON incident cases under the age of 20 during 2003-2015. The majority of pediatric MS (86.1%) and NMO (90.5%) patients were 10years old or above. The incidence of MS and ON was relatively steady, while that of NMO increased prominently later during the study period. The average incidence of pediatric MS and NMO during 2011-2015 was 0.52 and 0.11 per 100,000 person-years, respectively. The female preponderance was evident for pediatric MS and NMO, and less so for pediatric ON. The most common autoimmune comorbidities for pediatric MS were thyrotoxicosis (1.0%) and systemic lupus erythematosus (0.7%). The epidemiology of pediatric MS was largely stationary in Taiwan during 2001-2015, while the prevalence of pediatric NMO rose steeply during this period, probably reflecting better recognition of this clinical entity. Autoimmune comorbidities were uncommon for pediatric MS and NMO in Taiwan.

Characteristics of patients treated by the Danish Helicopter Emergency Medical Service from 2014-2018: a nationwide population-based study

BackgroundA national Helicopter Emergency Medical Service (HEMS) was introduced in Denmark in 2014 to ensure the availability of physician-led critical care for all patients regardless of location.Appropriate dispatch of HEMS is known to be complex, and resource utilisation is a highly relevant topic. Population-based studies on patient characteristics are fundamental when evaluating and optimising a system. The aim of this study was to describe the patient population treated by the Danish HEMS in terms of demographics, pre-hospital diagnostics, severity of illness or injury, and the critical care interventions performed.MethodThe study is a retrospective nationwide population-based study based on data gathered from the Danish HEMS database. We included primary missions resulting in a patient encounter registered between October 1st 2014 and April 30th 2018.ResultsOf 13.391 dispatches registered in the study period we included 7133 (53%) primary missions with patient encounter: 4639 patients were air lifted to hospital, 174 patients were escorted to hospital by the HEMS physician in an ambulance, and in 2320 cases HEMS assisted the ground crew on scene but did not escort the patient to hospital. Patient age ranged from 0-99 years and 64% of the population were men. The median age was 60 years.The main diagnostic groups were cardio-vascular emergencies (41%), trauma (23%) and neurological emergencies (16%). In 61% of the cases, the patient was critically ill/injured corresponding to a NACA (National Advisory Committee for Aeronautics) score between 4 and 7 (both included). In more than one third of the missions a critical care intervention was performed. Ultrasound examination and endo-tracheal intubation were the critical care interventions most frequently performed (21% and 20%, respectively).ConclusionThe national Danish HEMS primarily attends severely ill or injured patients and often perform critical care interventions. In addition, the Danish HEMS provides rapid transport to highly specialised treatment for patients in the more rural parts of the country.Patients with cardio-vascular emergencies, trauma and neurological emergencies are among those patient groups most commonly seen.We conclude that the overall dispatch profile appears appropriate but emphasise that continuous development and refinement is essential.

Epidemiology and Comorbidities of Psoriasis among Israeli Adolescents: A Large Cross-Sectional Study

Background and Aims: Although psoriasis can develop at any age, the data regarding its characteristics in adolescents are sparse. This study was designed to determine the psoriasis prevalence and its associations with the body mass index (BMI), lipid profile, and comorbidities in adolescents. Methods: This was a nationwide population-based cross-sectional retrospective study of adolescents (16–18 years old) evaluated for military service between January 1999 and January 2014. Results: Our database included 887,765 adolescents (57.1% males), of whom 3,112 (0.35%) were diagnosed with psoriasis. During the 15-year study period, the psoriasis prevalence increased by 1.4-fold, from 0.3 to 0.42% (1.25-fold for the males and 1.63-fold for the females). Certain comorbidities, such as contact dermatitis, hyperhidrosis, and arthritis, were significantly associated with psoriasis (odds ratios [ORs] of 2.26, 1.51, and 5.3, respectively). The adolescents with psoriasis had significantly elevated BMI and triglyceride values. We found increased ORs of 1.34 (95% confidence interval [CI] = 1.25–1.56) and 1.56 (95% CI = 1.32–1.83) for the overweight and obese adolescents, respectively, while a lower BMI (<20) had an opposite effect with psoriasis (OR = 0.8). Conclusions: Based on our results, the psoriasis prevalence in Israeli adolescents is rising. Dermatological comorbidities and an increased BMI were associated with psoriasis in these adolescents. A better understanding of the distinctive epidemiological characteristics of juvenile psoriasis may allow for the early detection of comorbidities and improve its management.

Should we pay attention to surgeon or hospital volume in total knee arthroplasty? Evidence from a nationwide population-based study.

BackgroundAlthough prior research into the relationship between volume and outcome indicates that this relationship is not linear and that an optimal volume should be specified, consensus is lacking regarding the ideal value of this optimal volume. The purposes of this study were to use a visual method to identify surgeon- and hospital-volume thresholds and to examine the relationships of surgeon and hospital volume thresholds to 30-day readmission.MethodsA retrospective nationwide population-based study design was adopted. Patients who received total knee replacement surgery between 2007 and 2008 in any hospital in Taiwan were included. After adjusting for patient, physician, and hospital characteristics, a restricted cubic spline regression model was used to identify optimal surgeon- and hospital-volume thresholds. Further, a patient-level mixed effect model was conducted to test the respective relationships between these thresholds and 30-day readmission.ResultsA total of 30,828 patients who had received their surgeries from 1,468 surgeons in 437 hospitals were included in this study. Thresholds of 50 cases a year for surgeons and 75 cases a year for hospitals were identified using a restricted cubic spline regression model. However, only the surgeon volume threshold was associated with 30-day readmission using a patient-level mixed effect model after adjusting for patient-, surgeon- and hospital-level covariates.ConclusionsAccording to the results of the restricted cubic spline models, the optimal volume thresholds for surgeons and hospitals are 50 cases and 75 cases a year, respectively. However, only the surgeon volume threshold is associated with 30-day readmission.

Risk for cervical herniated intervertebral disc in dentists: a nationwide population-based study

BackgroundProlonged static postures (PSPs) may predispose dentists to develop cervical herniated intervertebral disc (C-HIVD); however, there is limited evidence supporting this in the literature thus far. We conducted this study to fit the data gap.MethodsWe conducted a retrospective nationwide population-based study using the Taiwan National Health Insurance Research Database to identify 10,930 dentists, an identical number of age- and sex-matched participants from the general population, and 73,718 other health care providers (HCPs, non-dentists). Comparisons for the risk of developing C-HIVD between dentists and the general population, and between dentists and other HCPs were performed by tracing their medical histories between 2007 and 2011.ResultsDentists had a cumulative incidence rate of 1.1% for C-HIVD during the 5-year follow-up period. Overall, there was no difference of the risk for C-HIVD between dentists and the general population after adjusting for hypertension, hyperlipidemia, liver disease, mental disorders, diabetes mellitus, coronary artery disease, chronic obstructive pulmonary disease, malignancy, stroke, and renal disease (adjusted odds ratio [AOR]: 1.2, 95% confidence interval [CI]: 0.9–1.6). However, stratified analysis showed that younger dentists (≤ 34 years) had a trend of higher risk for C-HIVD than members of the younger general population (AOR: 1.9, 95% CI: 0.9–4.1). There was no difference found between dentists and other HCPs (AOR: 0.9, 95% CI: 0.8–1.1).ConclusionYounger dentists had a trend of higher risk of developing C-HIVD than members of the general population.

Penetrating stab injuries in Iceland: a whole-nation study on incidence and outcome in patients hospitalized for penetrating stab injuries

BackgroundStudies on penetrating injuries in Europe are scarce and often represent data from single institutions. The aim of this study was to describe the incidence and demographic features of patients hospitalized for stab injury in a whole nation.Materials and methodsThis was a retrospective nationwide population-based study on all consecutive adult patients who were hospitalized in Iceland following knife and machete-related injuries, 2000–2015. Age-standardized incidence was calculated and Injury Severity Score (ISS) was used to assess severity of injury.ResultsAltogether, 73 patients (mean age 32.6 years, 90.4% males) were admitted during the 16-year study period, giving an age-standardized incidence of 1.54/100,000 inhabitants. The incidence did not vary significantly during the study period (P = 0.826). Most cases were assaults (95.9%) occurring at home or in public streets, and involved the chest (n = 32), abdomen (n = 26), upper limbs (n = 26), head/neck/face (n = 21), lower limbs (n = 10), and the back (n = 6). Median ISS was 9, with 14 patients (19.2%) having severe injuries (defined as ISS > 15). The median length of hospital stay was 2 days (range 0–53). Forty-seven patients (64.4%) underwent surgery and 26 of them (35.6%) required admission to an intensive care unit (ICU), all with ISS scores above 15. Three patients did not survive for 30 days (4.1%); all of them had severe injuries (ISS 17, 25, and 75).ConclusionStab injuries that require hospital admission are rare in Iceland, and their incidence has remained relatively stable. One in every five patients sustained severe injuries, two-thirds of whom were treated with surgical interventions, and roughly one-third required ICU care. Although some patients were severely injured with high injury scores, their 30-day mortality was still low in comparison to other studies.