Influence of socioeconomic status on rates of advanced heart failure therapies.

BACKGROUND: Socioeconomic deprivation is associated with a lower likelihood of referral for advanced heart failure (HF) evaluation, but it is not known whether it influences rates of advanced HF therapies independently of key hemodynamic measures and comorbidity following advanced HF evaluation in a universal healthcare system. METHODS: We linked data from a single-center Danish clinical registry of consecutive patients evaluated for advanced HF with patient-level information on socioeconomic status. Patients were divided into groups based on the level of education (low, medium, and high), combined degree of socioeconomic deprivation (low, medium, and high), and household income quartiles. Rates of the combined outcome of left ventricular assist device implantation or heart transplantation (advanced HF therapy) with death as a competing risk were estimated with cumulative incidence functions, and Cox proportional hazards models adjusted for age, sex, central venous pressure, cardiac index, and comorbidities. RESULTS: We included 629 patients, median age 53 years, of whom 77% were men. During a median follow-up of 5 years, 179 (28%) underwent advanced HF therapy. The highest level of education was associated with higher rates (high vs low, adjusted HR 1.81 95% CI 1.14-2.89, p = 0.01), whereas household income quartile groups (Q4 vs Q1, adjusted HR 1.37 95% CI 0.76-2.47, p = 0.30) or groups of combined socioeconomic deprivation (high vs low degree of deprivation, adjusted HR 0.86 95% CI 0.50-1.46, p = 0.56) were not significantly associated with rates of advanced HF therapy. CONCLUSIONS: Patients with a lower level of education might be disfavored for advanced HF therapies and could require specific attention in the advanced HF care center.

Direct and indirect costs of heart failure in relation to diabetes status - A nationwide study.

BACKGROUND AND AIM: Heart failure (HF) and diabetes mellitus (DM) are burdensome chronic diseases with high lifetime risks and numerous studies indicate associations between HF and DM. The objective of this study was to investigate the direct and indirect costs of HF patients with and without DM. METHODS AND RESULTS: Patients with a first-time diagnosis of HF from 1998 to 2016 were identified through nationwide Danish registries and stratified according to DM status into HF with or without DM. The economic healthcare cost analysis was based on both direct costs, including hospitalization, procedures, medication and indirect costs including social welfare and lost productivity. The economic burden was investigated prior to, at, and following diagnosis of HF. Patients with concomitant HF and DM were younger (median age 74 vs. 77), had more comorbidities and fewer were female as compared to patients with HF but without DM. The socioeconomic burden of concomitant HF and DM compared to HF alone was substantially higher; 45% in direct costs (€16,237 vs. €11,184), 35% in home care costs (€3123 vs. €2320), 8% in social transfer income (€17,257 vs. €15,994) and they had 27% lower income (€10,136 vs. €13,845). The economic burden peaked at year of diagnosis, but the difference became increasingly pronounced in the years following the HF diagnosis. CONCLUSION: Patients with concomitant HF and DM had a significantly higher economic burden compared to patients with HF but without DM.

Importance of Risk Assessment in Timing of Invasive Coronary Evaluation and Treatment of Patients With Non-ST-Segment-Elevation Acute Coronary Syndrome: Insights From the VERDICT Trial.

Background The optimal timing of invasive examination and treatment of high-risk patients with non-ST-segment-elevation acute coronary syndrome has not been established. We investigated the efficacy of early invasive coronary angiography compared with standard-care invasive coronary angiography on the risk of all-cause mortality according to the GRACE (Global Registry of Acute Coronary Events) risk score in a predefined subgroup analysis of the VERDICT (Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography) trial. Methods and Results Patients with clinical suspicion of non-ST-segment-elevation acute coronary syndrome with ECG changes indicating new ischemia and/or elevated troponin, in whom invasive coronary angiography was clinically indicated and deemed logistically feasible within 12 hours, were eligible for inclusion. Patients were randomized 1:1 to an early (≤12 hours) or standard (48-72 hours) invasive strategy. The primary outcome of the present study was all-cause mortality. Of 2147 patients randomized in the VERDICT trial, 2092 patients had an available GRACE risk score. Of these, 1021 (48.8%) patients had a GRACE score >140. During a median follow-up of 4.1 years, 192 (18.8%) and 54 (5.0%) patients died in the high and low GRACE score groups, respectively. The risk of death with the early invasive strategy was increased in patients with a GRACE score ≤140 (hazard ratio [HR], 2.04 [95% CI, 1.16-3.59]), whereas there was a trend toward a decreased risk of death with the early invasive strategy in patients with a GRACE score >140 (HR, 0.83 [95% CI, 0.63-1.10]) (Pinteraction=0.006). Conclusions In patients with non-ST-segment-elevation acute coronary syndrome, we found a significant interaction between timing of invasive coronary angiography and GRACE score on the risk of death. Randomized clinical trials are warranted to establish the efficacy and safety among high-risk and low-risk patients with non-ST-segment-elevation acute coronary syndrome. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02061891.

Socioeconomic Disparities in Referral for Invasive Hemodynamic Evaluation for Advanced Heart Failure: A Nationwide Cohort Study.

BACKGROUND: Factors determining referral for advanced heart failure (HF) evaluation are poorly studied. We studied the influence of socioeconomic aspects on the referral process in Denmark, which has a taxpayer-funded national health care system. METHODS: We identified all patients aged 18 to 75 years with a first diagnosis of HF during 2010 to 2018. Hospitalized patients had to be discharged alive and were then followed for the outcome of undergoing a right heart catheterization (RHC) used as a surrogate marker of advanced HF work-up. RESULTS: Of 36 637 newly diagnosed patients with HF, 680 (1.9%) underwent RHC during the follow-up period (median time to RHC of 280 days [interquartile range, 73-914]). Factors associated with a higher likelihood of RHC included the highest versus lowest household income quartile (HR, 1.56 [95% CI, 1.19-2.06]; P=0.001), being diagnosed with HF at a tertiary versus nontertiary hospital (HR, 1.68 [95% CI, 1.37-2.05]; P<0.001) and during a hospitalization versus outpatient visit (HR, 1.67 [95% CI, 1.42-1.95]; P<0.001). Level of education, occupational status, and distance to tertiary hospital were not independently associated with RHC. Older age, cancer, and a psychiatric diagnosis were independently associated with a decreased probability of RHC. CONCLUSIONS: Higher household income, HF diagnosis during hospitalization, and first admission at a tertiary hospital were associated with increased likelihood of subsequent referral for RHC independent of other demographic and clinical variables. Greater attention may be required to ensure timely referral for advanced HF therapies in lower income groups.

Atrial fibrillation burden and cognitive decline in elderly patients undergoing continuous monitoring.

AIMS: To study the relationship between subclinical atrial fibrillation (AF) and changes in cognitive function in a large cohort of individuals with stroke risk factors. METHODS: Individuals with no prior AF diagnosis but with risk factors for stroke were recruited to undergo annual cognitive assessment with the Montreal Cognitive Assessment (MoCA) along with implantable loop recorder (ILR) monitoring for AF for 3 years. If AF episodes lasting ≥6 minutes were detected, oral anticoagulation (OAC) treatment was initiated. RESULTS: A total of 1194 participants (55.2 % men, mean age 74.5 (±3.9)) had a combined duration of heart rhythm monitoring of ≈1.3 million days. Among these, 339 participants (28.3%) had adjudicated AF, with a median AF burden of 0.072% (0.02, 0.39), and 324 (96%) initiated OAC. When stratifying the participants into AF burden groups (No AF, AFlow (AF burden <0.25%), and AFhigh, (AF burden >0.25%)), only participants in the AFlow group had a decrease in MoCA score over time (P = .03), although this was not significant after adjustment for stroke risk factors. A subgroup analysis of 175 participants (14.6%) with a MoCA <26 at 3 years found no association to AF diagnosis or burden. CONCLUSIONS: In a high-risk population, subclinical AF detected by continuous monitoring and subsequently treated with OAC was not associated with a significant change in MoCA score over a 3-year period.

Sex-Related Differences in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: To describe characteristics and outcomes in women and men with heart failure with preserved ejection fraction. METHODS: Baseline characteristics (including biomarkers and quality of life) and outcomes (primary outcome: composite of first heart failure hospitalization or cardiovascular death) were compared in 4458 women and 4010 men enrolled in CHARM-Preserved (Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity) (EF≥45%), I-Preserve (Irbesartan in heart failure with Preserved ejection fraction), and TOPCAT-Americas (Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist trial). RESULTS: Women were older and more often obese and hypertensive but less likely to have coronary artery disease or atrial fibrillation. Women had more symptoms and signs of congestion and worse quality of life. Despite this, the risk of the primary outcome was lower in women (hazard ratio, 0.80 [95% CI, 0.73-0.88]), as was the risk of cardiovascular death (hazard ratio, 0.70 [95% CI, 0.62-0.80]), but there was no difference in the rate for first hospitalization for heart failure (hazard ratio, 0.92 [95% CI, 0.82-1.02]). The lower risk of cardiovascular death in women, compared with men, was in part explained by a substantially lower risk of sudden death (hazard ratio, 0.53 [0.43-0.65]; P<0.001). E/A ratio was lower in women (1.1 versus 1.2). CONCLUSIONS: There are significant differences between women and men with heart failure with preserved ejection fraction. Despite worse symptoms, more congestion, and lower quality of life, women had similar rates of hospitalization and better survival than men. Their risk of sudden death was half that of men. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00853658, NCT01035255.

The economic burden of heart failure in Denmark from 1998 to 2016.

BACKGROUND: Heart failure (HF) imposes a large burden on both the individual and the society. The aim of this study was to investigate the economic burden (either direct or indirect costs) attributed to patients with HF before, at, and after time of diagnosis. METHODS AND RESULTS: Using Danish nationwide registries we identified all patients > 18 years with a first-time diagnosis of HF from 1998-2016 and matched them 1:1 with a control group from the background population on age, gender, marital status, and educational level. The economic analysis of the total costs after diagnosis was based on direct costs including hospitalization, procedures, medication, and indirect costs including social welfare and lost productivity to estimate the annual cost of HF. A total of 176 067 HF patients with a median age of 76 (interquartile range 67-84) years and 55% male were included. Patients with HF incurred an average of €17 039 in total annual direct (€11 926) and indirect (€5113) healthcare costs peaking at year of diagnosis compared to €5936 in the control group with the majority attributable to inpatient admissions. The total annual net costs including public transfer after index HF were €11 957 higher in patients with HF compared to controls and the economic consequences were evident more than 2 years prior to the diagnosis of HF. CONCLUSION: Patients with HF impose significantly higher total annual healthcare costs compared to a matched control group with findings evident more than 2 years prior to HF diagnosis.

Income Inequality and Outcomes in Heart Failure: A Global Between-Country Analysis.

OBJECTIVES: This study examined the relationship between income inequality and heart failure outcomes. BACKGROUND: The income inequality hypothesis postulates that population health is influenced by income distribution within a society, with greater inequality associated with worse outcomes. METHODS: This study analyzed heart failure outcomes in 2 large trials conducted in 54 countries. Countries were divided by tertiles of Gini coefficients (where 0% represented absolute income equality and 100% represented absolute income inequality), and heart failure outcomes were adjusted for standard prognostic variables, country per capita income, education index, hospital bed density, and health worker density. RESULTS: Of the 15,126 patients studied, 5,320 patients lived in Gini coefficient tertile 1 countries (coefficient: <33%), 6,124 patients lived in tertile 2 countries (33% to 41%), and 3,772 patients lived in tertile 3 countries (>41%). Patients in tertile 3 were younger than tertile 1 patients, were more often women, and had less comorbidity and several indicators of less severe heart failure, yet the tertile 3-to-1 hazard ratios (HRs) for the primary composite outcome of cardiovascular death or heart failure hospitalization were 1.57 (95% confidence interval [CI]: 1.38 to 1.79) and 1.48 for all-cause death (95% CI: 1.29 to 1.71) after adjustment for recognized prognostic variables. After additional adjustments were made for per capita income, education index, hospital bed density, and health worker density, these HRs were 1.46 (95% CI: 1.25 to 1.70) and 1.30 (95% CI: 1.10 to 1.53), respectively. CONCLUSIONS: Greater income inequality was associated with worse heart failure outcomes, with an impact similar to those of major comorbidities. Better understanding of the societal and personal bases of these findings may suggest approaches to improve heart failure outcomes.

Assessment of the myocardial area at risk: comparing T2-weighted cardiovascular magnetic resonance imaging with contrast-enhanced cine (CE-SSFP) imaging-a DANAMI3 substudy.

AIMS: Myocardial salvage following treatment for ST-segment elevation myocardial infarction is prognostic for morbidity and mortality. Studies with myocardial salvage as endpoint rely on valid assessment of the myocardial area at risk (AAR). T2-weighted cardiovascular magnetic resonance (CMR) imaging is the preferred method to assess the AAR. However, T2-weighted imaging can be of poor image quality and uninterpretable. Contrast-enhanced (CE) cine imaging can also show AAR and our aim was to investigate if CE-cine can replace T2-weighted imaging. Cine imaging is part of a standard CMR-protocol and implementing CE-cine imaging for assessment of the AAR would mean shorter investigation time. METHODS AND RESULTS: As a DANAMI-3 substudy, we performed successful dual imaging of the AAR in 166 participants using both T2-weighted short tau inversion recovery (T2-STIR) and CE-cine imaging. T2-STIR imaging was non-diagnostic in nine and CE-cine in one scan during the period. CE-cine measured 4.7% of left ventricle (LV) [95% confidence interval 3.2-6.2%] smaller AAR compared with T2-STIR images (P < 0.001). Visual analysis of a plot of infarct size vs. AAR showed an overestimation of the AAR when measured with T2-STIR images. There was no difference in AAR with CE-cine in an interobserver analysis of 46 scans [1.2 g (standard deviation 9.5), P = 0.42]. CONCLUSIONS: CE-cine imaging shows good internal consistency in assessment of the AAR. A visual inspection reveals possible overestimation of AAR with T2-STIR images. There is good interobserver agreement in the analysis of CE-cine imaging. CE-cine can replace T2-STIR imaging resulting in a more valid assessment of the myocardial AAR.

A simple clinical assessment is superior to systematic triage in prediction of mortality in the emergency department.

OBJECTIVE: To compare the Danish Emergency Process Triage (DEPT) with a quick clinical assessment (Eyeball triage) as predictors of short-term mortality in patients in the emergency department (ED). METHODS: The investigation was designed as a prospective cohort study conducted at North Zealand University Hospital. All patient visits to the ED from September 2013 to December 2013 except minor injuries were included. DEPT was performed by nurses. Eyeball triage was a quick non-systematic clinical assessment based on patient appearance performed by phlebotomists. Both triage methods categorised patients as green (not urgent), yellow, orange or red (most urgent). Primary analysis assessed the association between triage level and 30-day mortality for each triage method. Secondary analyses investigated the relation between triage level and 48-hour mortality as well as the agreement between DEPT and Eyeball triage. RESULTS: A total of 6383 patient visits were included. DEPT was performed for 6290 (98.5%) and Eyeball triage for 6382 (~100%) of the patient visits. Only patients with both triage assessments were included. The hazard ratio (HR) for 48-hour mortality for patients categorised as yellow was 0.9 (95% CI 0.4 to 1.9) for DEPT compared with 4.2 (95% CI 1.2 to 14.6) for Eyeball triage (green is reference). For orange the HR for DEPT was 2.2 (95% CI 1.1 to 4.4) and 17.1 (95% CI 5.1 to 57.1) for Eyeball triage. For red the HR was 30.9 (95% CI 12.3 to 77.4) for DEPT and 128.7 (95% CI 37.9 to 436.8) for Eyeball triage. For 30-day mortality the HR for patients categorised as yellow was 1.7 (95% CI 1.2 to 2.4) for DEPT and 2.4 (95% CI 1.6 to 3.5) for Eyeball triage. For orange the HR was 2.6 (95% CI 1.8 to 3.6) for DEPT and 7.6 (95% CI 5.1 to 11.2) for Eyeball triage, and for red the HR was 19.1 (95% CI 10.4 to 35.2) for DEPT and 27.1 (95% CI 16.9 to 43.5) for Eyeball triage. Agreement between the two systems was poor (kappa 0.05). CONCLUSION: Agreement between formalised triage and clinical assessment is poor. A simple clinical assessment by phlebotomists is superior to a formalised triage system to predict short-term mortality in ED patients.

Association between socioeconomic factors and ICD implantation in a publicly financed health care system: a Danish nationwide study.

Aims: For patients surviving out-of-hospital cardiac arrest (OHCA) with a shockable rhythm, implantable cardioverter defibrillator (ICD) is recommended for non-reversible causes of arrest. We aimed to determine factors associated with implantation of ICD and survival in patients surviving non-AMI OHCA in a nationwide register covering all OHCAs in Denmark. Methods and results: We identified 36 950 OHCAs between 2001 and 2012, 1700 of whom were ICD naïve, ≥18 years, of non-AMI cardiac aetiology and surviving until discharge. Six hundred fifty eight patients had ICD implanted during index admission. Association to ICD implantation during index admission was analysed in logistic regression, survival was assessed using Cox regression. Implantable cardioverter defibrillator implantation increased during the study period [odds ratio (OR) 1-year increase: 1.04, 95% confidence intervals (95% CI): 1.00-1.08, P = 0.03]. Non-shockable rhythm and age ≥70 years were associated with lower odds of ICD implantation (ORnon-shockable: 0.27, 95% CI: 0.19-0.37, P < 0.001, OR70-79 years: 0.71, 95% CI: 0.52-0.98, P = 0.04, OR≥80 years: 0.13, 95% CI: 0.07-0.22, P < 0.001). Non-AMI ischaemic heart disease, highest income tertile and chronic heart failure were associated with higher odds (ORIHD: 2.51, 95% CI: 1.77-3.60, P < 0.001, ORhighest income tertile: 1.58, 95% CI: 1.06-2.23, P = 0.02, ORHF: 1.77, 95% CI: 1.35-2.32, P < 0.001). Implantable cardioverter defibrillator implantation was associated with a lower risk of mortality (HR: 0.70, 95% CI: 0.53-0.92, P = 0.01). Conclusion: Implantable cardioverter defibrillator implantation rates increased over the study period. CHF, previous IHD and high income were associated with ICD implantation, while older age and non-shockable rhythm was associated with lower odds of ICD implantation. Implantable cardioverter defibrillator implantation was associated with higher survival rates.

Value of Myocardial Perfusion Assessment With Coronary Computed Tomography Angiography in Patients With Recent Acute-Onset Chest Pain.

OBJECTIVES: The authors sought to perform a randomized controlled trial to evaluate the clinical efficacy of combined examination with coronary computed tomography angiography (CTA) and computed tomography perfusion imaging (CTP) compared to coronary CTA alone. BACKGROUND: Stress myocardial CTP may increase diagnostic specificity when added to coronary CTA in patients suspected of having ischemic heart disease. METHODS: Patients recently hospitalized for acute-onset chest pain, who had acute coronary syndrome had been ruled out by normal electrocardiograms, normal troponin levels, and relief of symptoms, and who had a clinical indication for outpatient noninvasive testing, were screened for inclusion in the CATCH-2 (CArdiac cT in the treatment of acute CHest pain 2) trial (NCT02014311). Patients were randomized 1:1 to examination with coronary CTA or coronary CTA+CTP. The primary endpoint was the frequency of coronary revascularization among patients referred for invasive coronary angiography (ICA) based on index computed tomography evaluation. Secondary endpoints were invasive procedural complications at index-related ICA, post-index cardiac death, hospital admittance because of recurrence of chest pain, unstable angina pectoris, or acute myocardial infarction, ICA, and revascularization. RESULTS: Among 300 patients allocated to the coronary CTA+CTP group, 41 (14%) were referred for ICA compared with 89 (30%) allocated to coronary CTA (p < 0.0001). The primary endpoint occurred in 50% of coronary CTA+CTP patients versus 48% of invasively examined patients (p = 0.85). The total number of revascularizations was significantly lower in the coronary CTA+CTP group compared to the coronary CTA group (n = 20 [7%] vs. n = 42 [14%]; p = 0.0045). At median follow-up of 1.5 years, the occurrence of secondary endpoints was similar in the 2 groups. CONCLUSIONS: A post-discharge diagnostic strategy of coronary CTA+CTP safely reduces the need for invasive examination and treatment in patients suspected of having ischemic heart disease. (CArdiac cT in the treatment of acute CHest pain 2-Myocardial CT Perfusion [CATCH2]; NCT02014311).

Atrial fibrillation detected by continuous electrocardiographic monitoring using implantable loop recorder to prevent stroke in individuals at risk (the LOOP study): Rationale and design of a large randomized controlled trial.

Atrial fibrillation (AF) increases the rate of stroke 5-fold, and AF-related strokes have a poorer prognosis compared with non-AF-related strokes. Atrial fibrillation and stroke constitute an intensifying challenge, and health care organizations are calling for awareness on the topic. Previous studies have demonstrated that AF is often asymptomatic and consequently undiagnosed. The implantable loop recorder (ILR) allows for continuous, long-term electrocardiographic monitoring with daily transmission of arrhythmia information, potentially leading to improvement in AF detection and stroke prevention. METHODS: The LOOP study is an investigator-initiated, randomized controlled trial with 6,000 participants randomized 3:1 to a control group or to receive an ILR with continuous electrocardiographic monitoring. Participants are identified from Danish registries and are eligible for inclusion if 70years or older and previously diagnosed as having at least one of the following conditions: hypertension, diabetes mellitus, heart failure, or previous stroke. Exclusion criteria include history of AF and current oral anticoagulation treatment. When an AF episode lasting ≥6minutes is detected, oral anticoagulation will be initiated according to guidelines. Expected follow-up is 4years. The primary end point is time to stroke or systemic embolism, whereas secondary end points include time to AF diagnosis and death. CONCLUSION: The LOOP study will evaluate health benefits and cost-effectiveness of ILR as a screening tool for AF to prevent stroke in patients at risk. Secondary objectives include identification of risk factors for the development of AF and characterization of arrhythmias in the population. The trial holds the potential to influence the future of stroke prevention.

Copenhagen comorbidity in HIV infection (COCOMO) study: a study protocol for a longitudinal, non-interventional assessment of non-AIDS comorbidity in HIV infection in Denmark.

BACKGROUND: Modern combination antiretroviral therapy (cART) has improved survival for people living with HIV (PLWHIV). Non-AIDS comorbidities have replaced opportunistic infections as leading causes of mortality and morbidity, and are becoming a key health concern as this population continues to age. The aim of this study is to estimate the prevalence and incidence of non-AIDS comorbidity among PLWHIV in Denmark in the cART era and to determine risk factors contributing to the pathogenesis. The study primarily targets cardiovascular, respiratory, and hepatic non-AIDS comorbidity. METHODS/DESIGN: The Copenhagen comorbidity in HIV-infection (COCOMO) study is an observational, longitudinal cohort study. The study was initiated in 2015 and recruitment is ongoing with the aim of including 1500 PLWHIV from the Copenhagen area. Follow-up examinations after 2 and 10 years are planned. Uninfected controls are derived from the Copenhagen General Population Study (CGPS), a cohort study including 100,000 uninfected participants from the same geographical region. Physiological and biological measures including blood pressure, ankle-brachial index, electrocardiogram, spirometry, exhaled nitric oxide, transient elastography of the liver, computed tomography (CT) angiography of the heart, unenhanced CT of the chest and upper abdomen, and a number of routine biochemical analysis are uniformly collected in participants from the COCOMO study and the CGPS. Plasma, serum, buffy coat, peripheral blood mononuclear cells (PBMC), urine, and stool samples are collected in a biobank for future studies. Data will be updated through periodical linking to national databases. DISCUSSION: As life expectancy for PLWHIV improves, it is essential to study long-term impact of HIV and cART. We anticipate that findings from this cohort study will increase knowledge on non-AIDS comorbidity in PLWHIV and identify targets for future interventional trials. Recognizing the demographic, clinical and pathophysiological characteristics of comorbidity in PLWHIV may help inform development of new guidelines and enable us to move forward to a more personalized HIV care. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02382822 .

Identifying Drug-Drug Interactions by Data Mining: A Pilot Study of Warfarin-Associated Drug Interactions.

BACKGROUND: Knowledge about drug-drug interactions commonly arises from preclinical trials, from adverse drug reports, or based on knowledge of mechanisms of action. Our aim was to investigate whether drug-drug interactions were discoverable without prior hypotheses using data mining. We focused on warfarin-drug interactions as the prototype. METHODS AND RESULTS: We analyzed altered prothrombin time (measured as international normalized ratio [INR]) after initiation of a novel prescription in previously INR-stable warfarin-treated patients with nonvalvular atrial fibrillation. Data sets were retrieved from clinical work. Random forest (a machine-learning method) was set up to predict altered INR levels after novel prescriptions. The most important drug groups from the analysis were further investigated using logistic regression in a new data set. Two hundred and twenty drug groups were analyzed in 61 190 novel prescriptions. We rediscovered 2 drug groups having known interactions (ß-lactamase-resistant penicillins [dicloxacillin] and carboxamide derivatives) and 3 antithrombotic/anticoagulant agents (platelet aggregation inhibitors excluding heparin, direct thrombin inhibitors [dabigatran etexilate], and heparins) causing decreasing INR. Six drug groups with known interactions were rediscovered causing increasing INR (antiarrhythmics class III [amiodarone], other opioids [tramadol], glucocorticoids, triazole derivatives, and combinations of penicillins, including ß-lactamase inhibitors) and two had a known interaction in a closely related drug group (oripavine derivatives [buprenorphine] and natural opium alkaloids). Antipropulsives had an unknown signal of increasing INR. CONCLUSIONS: We were able to identify known warfarin-drug interactions without a prior hypothesis using clinical registries. Additionally, we discovered a few potentially novel interactions. This opens up for the use of data mining to discover unknown drug-drug interactions in cardiovascular medicine.

Out-of-hospital cardiac arrests in children and adolescents: incidences, outcomes, and household socioeconomic status.

BACKGROUND: There is insufficient knowledge of out-of-hospital cardiac arrest (OHCA) in the very young. OBJECTIVES: This nationwide study sought to examine age-stratified OHCA characteristics and the role of parental socioeconomic differences and its contribution to mortality in the young population. METHODS: All OHCA patients in Denmark, ≤21 years of age, were identified from 2001 to 2010. The population was divided into infants (<1 year); pre-school children (1-5 years); school children (6-15 years); and high school adolescents/young adults (16-21 years). Multivariate logistic regression analyses were used to investigate associations between pre-hospital factors and study endpoints: return of spontaneous circulation and survival. RESULTS: A total of 459 individuals were included. Overall incidence of OHCA was 3.3 per 100,000 inhabitants per year. The incidence rates for infants, pre-school children, school children and high school adolescents were 11.5, 3.5, 1.3 and 5.3 per 100,000 inhabitants. Overall bystander CPR rate was 48.8%, and for age groups: 55.4%, 41.2%, 44.9% and 63.0%, respectively. Overall 30-day survival rate was 8.1%, and for age groups: 1.4%, 4.5%, 16.1% and 9.3%, respectively. High parental education was associated with improved survival after OHCA (OR 3.48, CI 1.27-9.41). Significant crude difference in survival (OR 3.18, CI 1.22-8.34) between high household incomes vs. low household incomes was found. CONCLUSION: OHCA incidences and survival rates varied significantly between age groups. High parental education was found to be associated with improved survival after OHCA.

Dosage of angiotensin-II receptor blockers in heart failure patients following changes in Danish drug reimbursement policies.

PURPOSE: National reimbursement policies in Denmark were changed in November 2010 favouring a shift in angiotensin-II receptor blocker (ARB) treatment to generic losartan for heart failure (HF) patients. We examined how changes in reimbursement policies affected the fraction of HF patients up-titrated to optimal or suboptimal ARB dosage. METHODS: A historical cohort study was performed including HF patients with at least one prescription of ARB in the months of May-Jul 2010 (baseline). Patients were considered up-titrated at doses 100, 16 or 160 mg for losartan, valsartan and candesartan, respectively. Individual-level linkage of nationwide registries of hospitalization and drug dispensing in Denmark was used to describe patterns of ARB prescriptions and estimate dosage before and after November 2010. Logistic regression models were used to assess the probability for being up-titrated in the period. RESULTS: Of 6036 individuals included (mean age 73.5 [standard deviation 11.2] years; 51% males), 3346 (55.4%) used losartan, 541 (9.0%) valsartan and 2149 (35.6%) candesartan at inclusion, respectively. 2887 (47.8%) were up-titrated at baseline (May-Jul 2010), followed by 2878 (48.2%) in the three months before the policy change (Aug-Oct 2010), and 2492 (43.7%) in the first months after the policy change (Feb-Apr 2011). Odds ratios for being up-titrated according to time period were 1.02 [0.95-1.09] in Aug-Oct 2010 (before policy change) and 0.84 [0.78-0.90] in Feb-Apr 2011 (after policy change), compared with May-Jul 2010 (reference). CONCLUSION: Probability of being up-titrated in ARB treatment was reduced 20% following changes in drug reimbursement policies.

Effect of comprehensive cardiac rehabilitation after heart valve surgery (CopenHeartVR): study protocol for a randomised clinical trial.

BACKGROUND: Heart valve diseases are common with an estimated prevalence of 2.5% in the Western world. The number is rising due to an ageing population. Once symptomatic, heart valve diseases are potentially lethal, and heavily influence daily living and quality of life. Surgical treatment, either valve replacement or repair, remains the treatment of choice. However, post surgery, the transition to daily living may become a physical, mental and social challenge. We hypothesise that a comprehensive cardiac rehabilitation programme can improve physical capacity and self-assessed mental health and reduce hospitalisation and healthcare costs after heart valve surgery. METHODS: A randomised clinical trial, CopenHeartVR, aims to investigate whether cardiac rehabilitation in addition to usual care is superior to treatment as usual after heart valve surgery. The trial will randomly allocate 210 patients, 1:1 intervention to control group, using central randomisation, and blinded outcome assessment and statistical analyses. The intervention consists of 12 weeks of physical exercise, and a psycho-educational intervention comprising five consultations. Primary outcome is peak oxygen uptake (VO2 peak) measured by cardiopulmonary exercise testing with ventilatory gas analysis. Secondary outcome is self-assessed mental health measured by the standardised questionnaire Short Form 36. Also, long-term healthcare utilisation and mortality as well as biochemistry, echocardiography and cost-benefit will be assessed. A mixed-method design is used to evaluate qualitative and quantitative findings encompassing a survey-based study before the trial and a qualitative pre- and post-intervention study. DISCUSSION: The study is approved by the local regional Research Ethics Committee (H-1-2011-157), and the Danish Data Protection Agency (j.nr. 2007-58-0015). TRIAL REGISTRATION: ClinicalTrials.gov (http://NCT01558765).

Combining body mass index with measures of central obesity in the assessment of mortality in subjects with coronary disease: role of "normal weight central obesity".

OBJECTIVES: This study sought to assess the mortality risk of patients with coronary artery disease (CAD) based ona combination of body mass index (BMI) with measures of central obesity. BACKGROUND: In CAD patients, mortality has been reported to vary inversely with BMI ("obesity paradox"). In contrast,central obesity is directly associated with mortality. Because of this bidirectionality, we hypothesized that CAD patients with normal BMI but central obesity would have worse survival compared to individuals with other combinations of BMI and central adiposity. METHODS: We included 15,547 participants with CAD who were part of 5 studies from 3 continents. Multivariate stratifiedCox-proportional hazard models adjusted for potential confounders were used to assess mortality risk according to different patterns of adiposity that combined BMI with measures of central obesity. RESULTS: Mean age was 66 years, 60% were men. There were 5,507 deaths over a median follow-up of 2.4 years (IQR: 0.5 to 7.4 years). Individuals with normal weight central obesity had the worst long-term survival: a person with BMI of 22 kg/m2 and waist circumference (WC) of 101 cm had higher mortality than a person with similar BMI but WC of 85 cm (HR: 1.10[95% CI: 1.05 to 1.17]), than a person with BMI of 26 kg/m2 and WC of 85 cm (HR: 1.20 [95% CI: 1.09 to 1.31]), than a person with BMI of 30 kg/m2 and WC of 85 cm (HR: 1.61 [95% CI: 1.39 to 1.86]) and than a person with BMI of 30kg/m2 and WC of 101 cm (HR: 1.27 [95% CI: 1.18 to 1.39), p < 0.0001 for all). CONCLUSIONS: In patients with CAD, normal weight with central obesity is associated with the highest risk of mortality [corrected].

Comparative cardiovascular safety of dementia medications: a cross-national study.

OBJECTIVES: To compare the cardiovascular safety of currently marketed dementia medications in new users in the United States and Denmark. DESIGN: Retrospective cohort study. SETTING: Nationally representative sample of Medicare beneficiaries from 2006 through 2009 and nationwide Danish administrative registries from 1997 through 2007. PARTICIPANTS: Individuals treated with a dementia medication aged 65 and older. MEASUREMENTS: Hospitalizations for myocardial infarction (MI), heart failure, and syncope or atrioventricular block in both cohorts; fatal or nonfatal MI and cardiac death in the Danish cohort; and all-cause mortality in sensitivity analyses. RESULTS: In 46,737 Medicare beneficiaries and 29,496 Danish participants, donepezil was the most frequently used medication. There were no substantial differences in the risk of MI or heart failure between participants using donepezil and those using other cholinesterase inhibitors (all hazard ratios (HR) crossing 1). In the Danish cohort, memantine was associated with fatal or nonfatal MI (HR = 1.33, 95% confidence interval (CI) = 1.08-1.63), cardiac death (HR = 1.31, 95% CI = 1.12-1.53), and a trend toward higher rates of hospitalization for MI (HR = 1.31, 95% CI = 0.98-1.76). Memantine was also associated with greater risk of all-cause mortality in the Medicare (HR = 1.20, 95% CI = 1.13-1.28) and Danish (HR = 1.83, 95% CI = 1.73-1.94) cohorts, suggesting that sicker individuals were selected for memantine therapy. CONCLUSION: Cholinesterase inhibitors have similar cardiovascular risk profiles. Associations between memantine and fatal outcomes in Denmark may be related, in part, to selection of sicker individuals for memantine therapy.