Continued versus discontinued oxytocin stimulation in the active phase of labour (CONDISOX): individual management based on artificial intelligence - a secondary analysis.

BACKGROUND: Current guidelines regarding oxytocin stimulation are not tailored to individuals as they are based on randomised controlled trials. The objective of the study was to develop an artificial intelligence (AI) model for individual prediction of the risk of caesarean delivery (CD) in women with a cervical dilatation of 6 cm after oxytocin stimulation for induced labour. The model included not only variables known when labour induction was initiated but also variables describing the course of the labour induction. METHODS: Secondary analysis of data from the CONDISOX randomised controlled trial of discontinued vs. continued oxytocin infusion in the active phase of induced labour. Extreme gradient boosting (XGBoost) software was used to build the prediction model. To explain the impact of the predictors, we calculated Shapley additive explanation (SHAP) values and present a summary SHAP plot. A force plot was used to explain specifics about an individual's predictors that result in a change of the individual's risk output value from the population-based risk. RESULTS: Among 1060 included women, 160 (15.1%) were delivered by CD. The XGBoost model found women who delivered vaginally were more likely to be parous, taller, to have a lower estimated birth weight, and to be stimulated with a lower amount of oxytocin. In 108 women (10% of 1060) the model favoured either continuation or discontinuation of oxytocin. For the remaining 90% of the women, the model found that continuation or discontinuation of oxytocin stimulation affected the risk difference of CD by less than 5% points. CONCLUSION: In women undergoing labour induction, this AI model based on a secondary analysis of data from the CONDISOX trial may help predict the risk of CD and assist the mother and clinician in individual tailored management of oxytocin stimulation after reaching 6 cm of cervical dilation.

Using Explainable Artificial Intelligence to Predict Potentially Preventable Hospitalizations: A Population-Based Cohort Study in Denmark.

BACKGROUND: The increasing aging population and limited health care resources have placed new demands on the healthcare sector. Reducing the number of hospitalizations has become a political priority in many countries, and special focus has been directed at potentially preventable hospitalizations. OBJECTIVES: We aimed to develop an artificial intelligence (AI) prediction model for potentially preventable hospitalizations in the coming year, and to apply explainable AI to identify predictors of hospitalization and their interaction. METHODS: We used the Danish CROSS-TRACKS cohort and included citizens in 2016-2017. We predicted potentially preventable hospitalizations within the following year using the citizens' sociodemographic characteristics, clinical characteristics, and health care utilization as predictors. Extreme gradient boosting was used to predict potentially preventable hospitalizations with Shapley additive explanations values serving to explain the impact of each predictor. We reported the area under the receiver operating characteristic curve, the area under the precision-recall curve, and 95% confidence intervals (CI) based on five-fold cross-validation. RESULTS: The best performing prediction model showed an area under the receiver operating characteristic curve of 0.789 (CI: 0.782-0.795) and an area under the precision-recall curve of 0.232 (CI: 0.219-0.246). The predictors with the highest impact on the prediction model were age, prescription drugs for obstructive airway diseases, antibiotics, and use of municipality services. We found an interaction between age and use of municipality services, suggesting that citizens aged 75+ years receiving municipality services had a lower risk of potentially preventable hospitalization. CONCLUSION: AI is suitable for predicting potentially preventable hospitalizations. The municipality-based health services seem to have a preventive effect on potentially preventable hospitalizations.

Effects of a transitional care intervention on readmission among older medical inpatients: a quasi-experimental study.

PURPOSE: To evaluate the effect of a transitional care intervention (TCI) on readmission among older medical inpatients. METHODS: This non-randomised quasi-experimental study was conducted at Horsens Regional Hospital in Denmark from 1 February 2017 to 31 December 2018. Inclusion criteria were patients ≥ 75 years old admitted for at least 48 h. First, patients were screened for eligibility. Then, the allocation to the intervention or control group was performed according to the municipality of residence. Patients living in three municipalities were offered the hospital-based intervention, and patients living in a fourth municipality were allocated to the control group. The intervention components were (1) discharge transportation with a home visit, (2) a post-discharge cross-sectorial video conference and (3) seven-day telephone consultation. The primary outcome was 30-day unplanned readmission. Secondary outcomes were 30- and 90-day mortality and days alive and out of hospital (DAOH). RESULTS: The study included 1205 patients (intervention: n = 615; usual care: n = 590). In the intervention group, the median age was 84.3 years and 53.7% were females. In the control group, the median age was 84.9 years and 57.5% were females. The 30-day readmission rates were 20.8% in the intervention group and 20.2% in the control group. Adjusted relative risk was 1.00 (95% confidence interval: 0.80, 1.26; p = 0.99). No significant difference was found between the groups for the secondary outcomes. CONCLUSION: The TCI did not impact readmission, mortality or DAOH. Future research should conduct a pilot test, address intervention fidelity and consider real-world challenges. TRIAL REGISTRATION: Clinical trial number: NCT04796701. Registration date: 24 February 2021.

Interventions to Prevent Potentially Avoidable Hospitalizations: A Mixed Methods Systematic Review.

Background: The demand for healthcare is increasing due to an aging population, more people living with chronic diseases and medical comorbidities. To manage this demand, political institutions call for action to reduce the potentially avoidable hospitalizations. Quantitative and qualitative aspects should be considered to understand how and why interventions work, and for whom. The aim of this mixed methods systematic review was to identify and synthesize evidence on interventions targeting avoidable hospitalizations from the perspectives of the citizens and the healthcare professionals to improve the preventive healthcare services. Methods and Results: A mixed methods systematic review was conducted following the JBI methodology using a convergent integrated approach to synthesis. The review protocol was registered in PROSPERO, reg. no. CRD42020134652. A systematic search was undertaken in six databases. In total, 45 articles matched the eligibility criteria, and 25 of these (five qualitative studies and 20 quantitative studies) were found to be of acceptable methodological quality. From the 25 articles, 99 meaning units were extracted. The combined evidence revealed four categories, which were synthesized into two integrated findings: (1) Addressing individual needs through care continuity and coordination prevent avoidable hospitalizations and (2) Recognizing preventive care as an integrated part of the healthcare work to prevent avoidable hospitalizations. Conclusions: The syntheses highlight the importance of addressing individual needs through continuous and coordinated care practices to prevent avoidable hospitalizations. Engaging healthcare professionals in preventive care work and considering implications for patient safety may be given higher priority. Healthcare administers and policy-makers could support the delivery of preventive care through targeted educational material aimed at healthcare professionals and simple web-based IT platforms for information-sharing across healthcare settings. The findings are an important resource in the development and implementation of interventions to prevent avoidable hospitalizations, and may serve to improve patient safety and quality in preventive healthcare services.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=134652, identifier: CRD42020134652.

Healthcare Use in the Five Years Before a First Infertility Diagnosis: A Danish Register-Based Case-Control Study in the CROSS-TRACKS Cohort.

Purpose: Infertility may affect somatic and mental health later in life. Nevertheless, health status before diagnosed infertility is sparsely studied in women. We aimed to describe healthcare use in primary and secondary care before a first infertility diagnosis and compare use between cases and controls. Materials and Methods: The case-control study was based on register data and used incidence density sampling. From the CROSS-TRACKS Cohort, we included women residing in the Horsens area in Denmark in 2012-2018 (n = 54,175). Eligible women were aged 18-40 years, nulliparous, and living in heterosexual relationships. Cases were women with a first infertility diagnosis in the Danish National Patient Registry (index date). Five controls were matched on age, birth year, and calendar time. Through linkage to Danish national health registries, we identified general practitioner (GP) attendance, paraclinical examinations, hospital contacts, diagnoses, and redeemed prescriptions. Healthcare use from one year to five years before index date was compared with conditional logistic regression. Results: We identified 711 cases and 3555 controls. At one year before index date, cases consulted their GP (odds ratio (OR) = 5.2, 95% confidence interval (CI): 3.2, 8.3) and visited hospital (OR = 1.2, 95% CI: 1.0, 1.4) and redeemed prescriptions (OR = 2.3 95% CI: 1.9, 2.7) more often compared to controls. Cases more often had blood and hemoglobin tests performed, redeemed more drugs related to genitourinary and hormonal diseases, and were more often diagnosed with endocrine and genitourinary diseases in the year before a first infertility diagnosis compared to controls. Cases and controls had comparable healthcare use from five years to one year before a first infertility diagnosis. Conclusion: Cases and controls had similar healthcare use from five years to one year before a first infertility diagnosis. However, cases had a higher healthcare use in the year preceding a first infertility diagnosis compared to controls.

Risk of asbestosis, mesothelioma, other lung disease or death among motor vehicle mechanics: a 45-year Danish cohort study.

INTRODUCTION: The risk of asbestosis, malignant mesothelioma and lung cancer among motor vehicle mechanics is of concern because of potential exposure to chrysotile asbestos during brake, clutch and gasket repair and maintenance. Asbestos has also been used in insulation and exhaust systems. METHODS: We examined the long-term risk of incident mesothelioma, lung cancer, asbestosis and other lung diseases and mortality due to mesothelioma, lung cancer, asbestosis and other lung diseases in a nationwide cohort of all men registered as motor vehicle mechanics since 1970 in Denmark. This was compared with the corresponding risk in a cohort of male workers matched 10:1 by age and calendar year, with similar socioeconomic status (instrument makers, dairymen, upholsterers, glaziers, butchers, bakers, drivers, farmers and workers in the food industry, trade or public services). RESULTS: Our study included 138 559 motor vehicle mechanics (median age 24 years; median follow-up 20 years (maximum 45 years)) and 1 385 590 comparison workers (median age 25 years; median follow-up 19 years (maximum 45 years)). Compared with other workers, vehicle mechanics had a lower risk of morbidity due to mesothelioma/pleural cancer (n=47 cases) (age-adjusted and calendar-year-adjusted HR=0.74 (95% CI 0.55 to 0.99)), a slightly increased risk of lung cancer (HR=1.09 (95% CI 1.03 to 1.14)), increased risk of asbestosis (HR=1.50 (95% CI 1.10 to 2.03)) and a chronic obstructive pulmonary disease risk close to unity (HR=1.02 (95% CI 0.99 to 1.05)). Corresponding HRs for mortality were 0.86 (95% CI 0.64 to 1.15) for mesothelioma/pleural cancer, 1.06 (95% CI 1.01 to 1.12) for lung cancer, 1.79 (95% CI 1.10 to 2.92) for asbestosis, 1.06 (95% CI 0.86 to 1.30) for other lung diseases caused by external agents and 1.00 (95% CI 0.98 to 1.01) for death due to all causes. CONCLUSIONS: We found that the risk of asbestosis was increased among vehicle mechanics. The risk of malignant mesothelioma/pleural cancers was not increased among vehicle mechanics.

The Framing of machine learning risk prediction models illustrated by evaluation of sepsis in general wards.

Problem framing is critical to developing risk prediction models because all subsequent development work and evaluation takes place within the context of how a problem has been framed and explicit documentation of framing choices makes it easier to compare evaluation metrics between published studies. In this work, we introduce the basic concepts of framing, including prediction windows, observation windows, window shifts and event-triggers for a prediction that strongly affects the risk of clinician fatigue caused by false positives. Building on this, we apply four different framing structures to the same generic dataset, using a sepsis risk prediction model as an example, and evaluate how framing affects model performance and learning. Our results show that an apparently good model with strong evaluation results in both discrimination and calibration is not necessarily clinically usable. Therefore, it is important to assess the results of objective evaluations within the context of more subjective evaluations of how a model is framed.

Cohort profile: CROSS-TRACKS: a population-based open cohort across healthcare sectors in Denmark.

PURPOSE: This paper describes the open cohort CROSS-TRACKS, which comprises population-based data from primary care, secondary care and national registries to study patient pathways and transitions across sectors while adjusting for sociodemographic characteristics. PARTICIPANTS: A total of 221 283 individuals resided in the four Danish municipalities that constituted the catchment area of Horsens Regional Hospital in 2012-2018. A total of 96% of the population used primary care, 35% received at least one transfer payment and 66% was in contact with a hospital at least once in the period. Additional clinical information is available for hospital contacts (eg, alcohol intake, smoking status, body mass index and blood pressure). A total of 23% (n=8191) of individuals aged ≥65 years had at least one potentially preventable hospital admission, and 73% (n=5941) of these individuals had more than one. FINDINGS TO DATE: The cohort is currently used for research projects in epidemiology and artificial intelligence. These projects comprise a prediction model for potentially preventable hospital admissions, a clinical decision support system based on artificial intelligence, prevention of medication errors in the transition between sectors, health behaviour and sociodemographic characteristics of men and women prior to fertility treatment, and a recently published study applying machine learning methods for early detection of sepsis. FUTURE PLANS: The CROSS-TRACKS cohort will be expanded to comprise the entire Central Denmark Region consisting of 1.3 million residents. The cohort can provide new knowledge on how to best organise interventions across healthcare sectors and prevent potentially preventable hospital admissions. Such knowledge would benefit both the individual citizen and society as a whole.

Rheumatoid Arthritis as a Risk Factor for Coronary Artery Calcification and Obstructive Coronary Artery Disease in Patients with Chest Pain: A Registry Based Cross-Sectional Study.

PURPOSE: To examine the occurrence and severity of coronary artery disease (CAD) in patients with rheumatoid arthritis (RA) compared to non-RA patients in a population referred for coronary computed tomography angiography (CTA) due to chest pain. PATIENTS AND METHODS: In this cross-sectional study, 46,210 patients from a national CTA database were included. Patients with RA were stratified on serology, treatment with conventional synthetic or biological disease-modifying antirheumatic drugs (DMARDs), and the need for relapse or flare treatment with intraarticular or -muscular glucocorticoid injections (GCIs). Primary outcomes were coronary artery calcium score (CACS) >0 and CACS ≥400, and secondary outcome was obstructive CAD. Associations between RA and outcomes were examined using logistic regression and results were adjusted for age, sex, cardiovascular risk factors and comorbidities. RESULTS: A total of 395 (0.9%) RA patients were identified. In overall RA, crude odds ratio (OR) for having CACS >0 was 1.48 (1.21-1.82) and 1.52 (1.15-2.01) for CACS ≥400, whereas adjusted ORs were 1.08 (0.86-1.36) and 1.21 (0.89-1.65), respectively. Seropositive RA patients had adjusted OR of 1.16 (0.89-1.50) for CACS >0 and 1.37 (0.98-1.90) for CACS ≥400. Patients who had received ≥1 GCI in the period of 3 years prior to the CTA had an adjusted OR of 1.37 (0.94-2.00) for having CACS >0 and 1.46 (0.92-2.31) for CACS ≥400. CONCLUSION: This is the first large-scale, CTA-based study examining the occurrence and severity of CAD in RA patients with symptoms suggestive of cardiovascular disease. A higher prevalence of coronary artery calcification was found in RA patients. After adjusting for age, sex, cardiovascular risk factors and comorbidities, the tendency was less pronounced. We found a trend for increased coronary calcification in RA patients being seropositive or needing treatment with GCI for a relapse or flare.

​Risk of major adverse cardiovascular events among patients with rheumatoid arthritis after initial CT-based diagnosis and treatment.

OBJECTIVE: Rheumatoid arthritis (RA) is a known risk factor for developing coronary artery disease (CAD). The influence of RA on the prognosis after initial CAD diagnosis and treatment is however largely unknown. We examined the risk of major cardiovascular events among RA and non-RA patients with chest pain referred to cardiac CT. METHODS: This was a follow-up study, using data from the Western Denmark Heart Registry, containing data on CT angiography examinations (Cardiac CT). Information on RA diagnosis and covariates were identified through nationwide administrative registers. The primary outcome was a combined outcome including, myocardial infarction, ischaemic or unspecified stroke, coronary artery bypass grafting, percutaneous coronary intervention, and all-cause mortality. Median time until events or censoring was 3.5 years (min/max: 0.0: 9.2). Cox proportional hazard models were used to examine the association between RA/non-RA patients and outcomes. RESULTS: Among 42 257 patients, referred between 2008 and 2016, we identified 358 (0.8%) with RA. An increased risk was seen in RA compared with non-RA (adjusted HR 1.35, 95% CI 0.93 to 1.96). Among patients who had received flare treatment more than once prior to cardiac CT the adjusted HR 1.80 (95% CI 1.08 to 3.00), and among patients with seropositive RA the adjusted HR 1.42 (95% CI 0.93 to 2.16). CONCLUSION: In patients referred to cardiac CT due to chest pain, we found a trend of an association between RA and the combined primary outcome, supporting that RA per se, but in particular seropositive and active RA, may increase the risk of CAD even after initial CAD diagnosis and treatment.

Nitrosatable drug exposure during pregnancy and risk of stillbirth.

PURPOSE: Nitrosatable drugs can react with nitrite in the stomach and form N-nitroso compounds. Exposure to nitrosatable drugs has been associated with congenital malformations and preterm birth, but use during pregnancy as a cause of fetal death is not well-known. We examined if prenatally nitrosatable drug use is associated with risk of stillbirth. METHODS: A nationwide cohort was conducted using 554 844 women with singleton and first recorded pregnancies regardless of previous pregnancy history from the Danish Medical Birth Register from 1996 to 2015. Exposure was recorded by use of the Danish National Prescription Register and defined as women who had redeemed a prescribed nitrosatable drug in the first 22 weeks of pregnancy. The reference group was women with no redeemed prescribed nitrosatable drug in this time period. We categorized nitrosatable drugs as secondary amines, tertiary amines, and amides. Cox hazard regression was used to estimate crude and adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) for stillbirth. RESULTS: Among the 84 720 exposed women, 348 had a stillbirth compared with 1690 stillbirths among the 470 124 unexposed women. Women who used any prescribed nitrosatable drug were more likely to have a stillbirth compared with unexposed women (aHRs 1.24; 95% CI, 1.03-1.49). CONCLUSION: Nitrosatable drug use during the first 22 weeks of pregnancy might increase risk of stillbirth. The findings should be interpreted cautiously because of important unmeasured factors that might influence the observed association, including maternal vitamin C intake, dietary, and other sources of nitrate/nitrite intake.

The potential impact of paternal age on risk of asthma in childhood: a study within the Danish National Birth Cohort.

BACKGROUND: Advanced paternal age has been associated with offspring morbidity and mortality, possibly due to de novo mutations and epigenetic changes in male germ cells. Epigenetic changes in the cord blood cells have been linked to asthma symptoms in offspring, but the role of paternal age has been less studied. METHODS: From the Danish National Birth Cohort, 48,785 children who completed the 7-year follow-up were included. Parental reports of physician-diagnosed asthma had been obtained by a posted or web-based questionnaire. Paternal age at delivery was obtained through linkage with maternal civil registration number in the Danish Civil Registration System and classified into four groups: ≤24, 25-34 (reference), 35-39, and >40 years. We calculated the prevalence proportion of asthma and prevalence ratios (PRs) with 95% confidence intervals (CIs) using log-binomial regression, adjusting for paternal smoking, paternal asthma, and paternal socioeconomic status. RESULTS: At the 7-year follow-up, 5875 children (12%) had physician-diagnosed asthma. The prevalence of asthma in 7-year old children was higher with paternal age of ≤24 (adjusted PR 1.40; 95% CI: 1.26; 1.55) and lower with the paternal age of ≥35 years (adjusted PR 0.84; 95% CI: 0.78; 0.89) compared to the reference group. CONCLUSIONS: Paternal age of ≥35 years was associated with a lower prevalence of asthma in childhood, and paternal age of ≤24 years with higher prevalence compared with paternal age of 25-34 years. The potential causes of higher asthma prevalence among offspring of young fathers warrant further investigation.

Impact of Allogeneic Stem Cell Transplantation in First Complete Remission in Acute Myeloid Leukemia: A National Population-Based Cohort Study.

To examine the outcomes of allogeneic stem cell transplantation (HSCT) in first complete remission (CR1) compared with chemotherapy alone in a population-based setting, we identified a cohort of patients with acute myeloid leukemia (AML) aged 15 to 70 years diagnosed between 2000 and 2014 in Denmark. Using the Danish National Acute Leukemia Registry, we compared relapse risk, relapse-free survival (RFS), and overall survival (OS) between patients with unfavorable cytogenetic features receiving postremission therapy with conventional chemotherapy only versus those undergoing HSCT in CR1. To minimize immortal time bias, we performed Cox proportional hazards regression, included date of allogeneic HSCT as a time-dependent covariate, and stratified the results by age (<60 or ≥60 years) and cytogenetic risk group. Overall, 1031 patients achieved a CR1. Of these, 196 patients (19%) underwent HSCT. HSCT was associated with a lower relapse rate (24% versus 49%) despite a similar median time to relapse (287 days versus 265 days). In all subgroups, the risk of relapse was lower and both RFS and OS were superior in recipients of HSCT (OS, adjusted mortality ratios: all patients, .54 [95% confidence interval (CI), .42-.71]; patients age <60 years, .58 [95% CI, .42-.81]; patients age ≥60 years, .42 [95% CI, .26-.69]; patients with intermediate-risk cytogenetics, .63 [95% CI, .43-.87]; patients with adverse-risk cytogenetics, .40 [95% CI, .24-.67]). In conclusion, in this population-based nationwide cohort study, HSCT was associated with improved survival in both younger and older patients and in patients with both intermediate and adverse cytogenetic risk.

Out-of-hours and weekend admissions to Danish medical departments: admission rates and 30-day mortality for 20 common medical conditions.

OBJECTIVES: Knowledge on timing of admissions and mortality for acute medical patients is limited. The aim of the study was to examine hospital admission rates and mortality rates for patients with common medical conditions according to time of admission. DESIGN: Nationwide population-based cohort study. SETTING: Population of Denmark. PARTICIPANTS: Using the Danish National Registry of Patients covering all Danish hospitals, we identified all adults with the first acute admission to a medical department in Denmark during 2010. PRIMARY AND SECONDARY OUTCOME MEASURES: Hourly admission rates and age-standardised and sex-standardised 30-day mortality rates comparing weekday office hours, weekday out of hours, weekend daytime hours and weekend night-time hours. RESULTS: In total, 174,192 acute medical patients were included in the study. The admission rates (patients per hour) were 38.7 (95% CI 38.4 to 38.9) during weekday office hours, 13.3 (95% CI 13.2 to 13.5) during weekday out of hours, 19.8 (95% CI 19.6 to 20.1) during weekend daytime hours and 7.9 (95% CI 7.8 to 8.0) during weekend night-time hours. Admission rates varied between medical conditions. The proportion of patients admitted to an intensive care unit (ICU) increased outside of office hours. The age-standardised and sex-standardised 30-day mortality rate was 5.1% (95% CI 5.0% to 5.3%) after admission during weekday office hours, 5.7% (95% CI 5.5% to 6.0%) after admission during weekday out of hours, 6.4% (95% CI 6.1% to 6.7%) after admission during weekend daytime hours and 6.3% (95% CI 5.9% to 6.8%) after admission during weekend night-time hours. For the majority of the medical conditions examined, weekend admission was associated with highest mortality. CONCLUSIONS: While admission rates decreased from office hours to weekend hours there was an observed increase in mortality. This may reflect differences in severity of illness as the proportion admitted to an ICU increased during the weekend.

Acute admissions to medical departments in Denmark: diagnoses and patient characteristics.

BACKGROUND: Despite extensive research on individual diseases, population-based knowledge about reasons for acute medical admissions remains limited. Our aim was to examine primary diagnoses, Charlson Comorbidity Index (CCI) score, age, and gender among patients admitted acutely to medical departments in Denmark. METHODS: In this population-based observational study, 264,265 acute medical patients admitted during 2010 were identified in the Danish National Registry of Patients (DNRP), covering all hospitals in Denmark. Reasons for acute admissions were assessed by primary diagnoses, grouped according to the International Classification of Diseases 10th edition. Additionally, the CCI score, age and gender were presented according to each diagnostic group. RESULTS: Two-thirds of the patients had one of the four following reasons for admission: cardiovascular diseases (19.3%), non-specific Z-diagnoses ("Factors influencing health status and contact with health services") (16.9%), infectious diseases (15.5%), and non-specific R-diagnoses ("Symptoms and abnormal findings, not elsewhere classified") (11.8%). In total, 45% of the patients had a CCI score of one or more and there was a considerable overlap between the patients' chronic diseases and the reason for admission. The median age of the study population was 64 years (IQR 47-77 years), ranging from 46 years (IQR 27-66) for injury and poisoning to 74 years (IQR 60-83) for hematological diseases. Gender representation varied considerably within the diagnostic groups, for example with male predominance in mental disorders (59.0%) and female predominance in diseases of the musculoskeletal system (57.8%). CONCLUSION: Our study identifies that acute medical patients often present with non-specific symptoms or complications related to their chronic diseases.

Registration of acute medical hospital admissions in the Danish National Patient Registry: a validation study.

BACKGROUND: In recent years, the number of acute hospital admissions has increased and this has imposed both organizational and financial strains on the health care system. Consequently, it is of crucial importance that we have valid data on admission types in the administrative databases in order to provide data for health care planning and research. OBJECTIVE: To examine the validity of registration of acute admissions among medical patients in the Danish National Patient Registry (DNPR) using medical record reviews as the reference standard. METHODS: We used the nationwide DNPR to identify a sample of 160 medical patients admitted to a hospital in the North Denmark Region during 2009. Data on admission type was obtained from the DNPR and confirmed by a medical record review. We computed positive predictive values, sensitivity, and specificity including 95% confidence intervals (CI) using the medical record review as the reference standard. RESULTS: Among the 160 medical inpatients identified in the DNPR, 128 were registered with an acute admission, and 32 were registered with a nonacute admission. Two medical records could not be located. Thus, the analyses included 158 medical patients. Among the 127 patients registered with acute admission, 124 were confirmed to be correctly classified. Correspondingly, 28 of the 31 patients with a registered nonacute admission were confirmed to be correctly classified. The overall positive predictive value of the acute admissions among medical patients was 97.6% (95% CI, 93.8%-99.3%). Sensitivity was 97.6% (95% CI, 93.8%-99.3%) and specificity was 90.3% (95% CI, 76.4%-97.2%). CONCLUSION: The registration of acute admission among medical patients in the DNPR has high validity.

The impact of statin use on pneumonia risk and outcome: a combined population-based case-control and cohort study.

INTRODUCTION: The impact of statin use on pneumonia risk and outcome remains unclear. We therefore examined this risk in a population-based case-control study and did a 5-year update of our previous 30-day mortality analyses. METHODS: We identified 70,953 adults with a first-time hospitalization for pneumonia between 1997 and 2009 in Northern Denmark. Ten age- and sex-matched population controls were selected for each pneumonia patient. To control for potential confounders, we retrieved individual-level data on other medications, comorbidities, recent surgery, socioeconomic indicators, influenza vaccination, and other markers of frailty or health awareness from medical databases. We followed all pneumonia patients for 30 days after hospital admission. RESULTS: A total of 7,223 pneumonia cases (10.2%) and 64,523 controls (9.1%) were statin users before admission, corresponding to an age- and sex-matched odds ratio (OR) of 1.17 (95% confidence interval [CI]: 1.14-1.21). After controlling for higher comorbidity and a wide range of other potential confounders, the adjusted OR for pneumonia associated with current statin use dropped to 0.80 (95% CI: 0.77-0.83). Previous statin use was not associated with decreased pneumonia risk (adjusted OR = 0.97, 95% CI: 0.91-1.02). Decreased risk remained significant after further adjustment for frailty and health awareness markers. CONCLUSIONS: Current statin use was associated with both a decreased risk of hospitalization for pneumonia and lower 30-day mortality following pneumonia.

Impact of diabetes and poor glycaemic control on risk of bacteraemia with haemolytic streptococci groups A, B, and G.

BACKGROUND: Diabetes has been associated with bacteraemia due to haemolytic streptococci but epidemiological evidence is limited. METHODS: We conducted a 15-year population-based case-control study of all adults with first-time bacteraemia with groups A, B, and G haemolytic streptococci and matched population controls. The study setting was Northern Denmark between 1992 and 2006. We computed odds ratios (ORs) for streptococcal bacteraemia according to diabetes and glycaemic control, using regression analysis for confounder adjustment. RESULTS: We identified 397 adult patients with bacteraemia due to haemolytic streptococci (median age 67 years, 51% women), of which 63 (17%) had diabetes. Persons with diabetes had a 2.1-fold increased risk of streptococcal bacteraemia compared with population controls (adjusted odds ratio (OR) 2.1; 95% confidence interval (CI), 1.5-2.9). For persons with type 1 diabetes, the adjusted OR was 14.8 (2.4-91.2). Longer diabetes duration and poor glycaemic control conferred higher risk estimates: adjusted OR 1.5 (0.8-3.0) for HbA(1c) level <7%, and OR 3.6 (1.6-8.1) for HbA(1c) level ≥9%. The association between diabetes and HS bacteraemia was independent of the underlying foci of infection and was strongest for group B streptococcal bacteraemia (OR 3.5; 1.8-7.0) and for group G streptococcal bacteraemia (OR 2.6; 1.6-4.4). There was no clear increase in risk for group A streptococcal bacteraemia (OR 1.2; 0.7-2.2). CONCLUSIONS: Diabetes is a strong risk factor for group B and group G, but not group A, haemolytic streptococcal bacteraemia. The risk increase is particularly high for type 1 diabetes, long diabetes duration, and poor long-term glycaemic control.

Neither long-term statin use nor atherosclerotic disease is associated with risk of colorectal cancer.

BACKGROUND & AIMS: Statin use has been reported to reduce risk for colorectal cancer (CRC) whereas atherosclerotic disease has been reported to increase risk, but findings have been inconsistent. We aimed to establish the association of statin use and coronary atherosclerosis with CRC. METHODS: We performed a population-based case control study of patients with a first diagnosis of CRC cancer between January 1, 1991, and December 31, 2008 (n = 9979), using the Danish National Registry of Patients. As many as 10 population controls were matched to each patient using risk set sampling (n = 99,790). Statin use before cancer diagnosis (or control index date) was determined via county prescription databases and evidence of coronary atherosclerosis using International Classification of Diseases codes. We calculated incidence rate ratios using conditional logistic regression, adjusted for multiple covariates. RESULTS: Among patients with CRC, statin use was modest (7.7%), but 23.5% of use was long term (≥5 years). Ever use of statins (≥2 prescriptions) slightly reduced CRC risk, compared with relative to never/rare use (incidence rate ratio [IRR] = 0.87, 95% confidence interval = 0.80-0.96). However, long-term use did not affect risk compared with never/rare use (IRR = 0.95, 95% 0.80-1.12). No associations were observed between atherosclerosis, myocardial infarction, or stroke, and CRC incidence. CONCLUSIONS: Although there is a weak inverse association between ever use of statins and CRC incidence, there was no trend with increasing duration of use, so statins do not appear to reduce CRC risk. We did not confirm the reported association between atherosclerosis and CRC risk.

Statin use and risk of amyotrophic lateral sclerosis and other motor neuron disorders.

BACKGROUND: Use of statins has been associated with an amyotrophic lateral sclerosis-like syndrome in 2 analyses of overlapping surveillance databases that record adverse events potentially related to prescription drug use. We assessed whether statin use is associated with the occurrence of amyotrophic lateral sclerosis and other motor neuron disorders. METHODS AND RESULTS: We conducted a population-based case-control study in Northern Denmark, with a population of 1.8 million. From the Danish National Registry of Patients, we identified incident cases coded with amyotrophic lateral sclerosis or other motor neuron syndromes during the period from 1999 to 2008. We selected 10 population control subjects matched to cases on sex, birth year, and calendar time. Statin use was ascertained in the prescription database in the region--and so recorded before diagnosis--and associated with disease occurrence by conditional logistic regression adjusting for covariates. We identified 556 cases of amyotrophic lateral sclerosis or other motor neuron syndromes and 5560 population control subjects. The odds ratio associating disease occurrence with statin use was 0.96 (95% confidence interval, 0.73 to 1.28). Recent users of statins, former users, and users of short or long duration had similarly near-null associations. CONCLUSIONS: Any risk of amyotrophic lateral sclerosis associated with statin use probably is small, so outweighed by the important clinical advantages of statin medications to prevent and treat cardiovascular diseases.