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Redox flow batteries (RFBs) are a promising stationary energy storage technology for leveling power supply from intermittent renewable energy sources with demand. A central objective for the development of practical, scalable RFBs is to identify affordable and high-performance redox-active molecules as storage materials. Herein, we report the design, synthesis, and evaluation of a new organic scaffold, indolo[2,3- b ]quinoxaline, for highly stable, low-reduction potential, and high-solubility anolytes for nonaqueous redox flow batteries (NARFBs). The mixture of 2- and 3-( tert -butyl)-6-(2-methoxyethyl)-6 H -indolo[2,3- b ]quinoxaline exhibits a low reduction potential (-2.01 V vs Fc/Fc + ), high solubility (>2.7 M in acetonitrile), and remarkable stability (99.86% capacity retention over 49.5 h (202 cycles) of H-cell cycling). This anolyte was paired with N -(2-(2-methoxyethoxy)-ethyl)phenothiazine (MEEPT) to achieve a 2.3 V all-organic NARFB exhibiting 95.8% capacity retention over 75.1 h (120 cycles) of cycling.

Understanding the bonding of gold(I) species has been central to the development of gold(I) catalysis. Herein, we present the synthesis and characterization of the first gold(I)-cyclobutadiene complex, accompanied with bonding analysis by state-of-the-art energy decomposition analysis methods. Analysis of possible coordination modes for the new species not only confirms established characteristics of gold(I) bonding, but also suggests that Pauli repulsion is a key yet hitherto overlooked element. Additionally, we obtain a new perspective on gold(I)-bonding by comparison of the gold(I)-cyclobutadiene to congeners stabilized by p-, d-, and f-block metals. Consequently, we refine the gold(I) bonding model, with a delicate interplay of Pauli repulsion and charge transfer as the key driving force for various coordination motifs. Pauli repulsion is similarly determined as a significant interaction in Au I -alkyne species, corroborating this revised understanding of Au I bonding., (© 2022 Wiley-VCH GmbH.)

Aims: Metformin is the first-line treatment for most patients with type 2 diabetes but many patients need additional treatment with insulin secretagogues (IS) to achieve glycemic control. We aimed to compare mortality and cardiovascular risk among users of metformin in combination with pharmacologically different ISs., Methods: Using nationwide administrative Danish registries, we followed all individuals without prior stroke or myocardial infarction who initiated metformin and an IS from 1997 through 2009. Rate ratios (RR) of all-cause mortality, cardiovascular death, and a composite of myocardial infarction, stroke, or cardiovascular death were compared between user groups using time-dependent multivariable Poisson regression models. The most common combination, glimepiride+metformin, was used as reference., Results: A total of 56,827 patients were included, 56% male, the mean age was 61 ± 12.5 years, and median duration of prior monotherapy was 2.2 (inter quartile range 0.5-4.5) years. Crude incidence rates of mortality for combinations of ISs with metformin were; 15.4 (repaglinide), 28.1 (glipizide), 23.7 (glibenclamide), 21.1 (gliclazide), 20.7 (glimepiride), 27.7 (tolbutamide) deaths per 1000 person years. In adjusted analysis, the associated mortality risk was similar for users of gliclazide+metformin (RR=1.01 [0.88-1.15]), repaglinide+metformin (RR=0.81 [0.62-1.05]), glibenclamide+metformin (RR=0.98 [0.87-1.10]), and tolbutamide+metformin (RR=1.04 [0.85-1.28]). Users of glipizide+metformin was associated with increased all-cause mortality (RR=1.16 [1.02-1.32], p=0.02), cardiovascular death (RR=1.21 [1.01-1.46], p=0.04), and the combined endpoint (RR=1.20 [1.06-1.36, p=0.005)., Conclusion: Most ISs in combination with metformin were associated with similar mortality and cardiovascular risk. Whether glipizide is associated with increased risk compared with other ISs when used in combinations with metformin warrants further study., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Aims/hypothesis: Individual sulfonylureas (SUs) and metformin have, in some studies, been associated with unequal hypoglycaemic, cardiovascular and mortality risks when used as monotherapy in type 2 diabetes. We investigated the outcomes in patients treated with different combinations of SUs and insulin vs a combination of metformin and insulin in a retrospective nationwide study., Methods: All Danish individuals using dual therapy with SU + insulin or metformin + insulin without prior myocardial infarction (MI) or stroke were followed from 1 January 1997 to 31 December 2009 in nationwide registries. Risks of all-cause mortality, cardiovascular death, hypoglycaemia and a composite endpoint of MI, stroke and cardiovascular death were compared. Rate ratios (RR) [95% CIs] were calculated using time-dependent multivariable Poisson regression analysis., Results: A total of 11,081 patients used SU + insulin and 16,910 used metformin + insulin. Patients receiving metformin + insulin were younger and had less comorbidity and a longer history of glucose-lowering treatment. SU + insulin was associated with higher mortality rates compared with metformin + insulin (76-126 vs 23 per 1,000 person-years). In adjusted analyses, SU + insulin was associated with increased all-cause mortality (RR 1.81 [1.63, 2.01]), cardiovascular death (RR 1.35 [1.14, 1.60]) and the composite endpoint (RR 1.25 [1.09, 1.42]) compared with metformin + insulin. Hypoglycaemia was more frequent with SU + insulin than with metformin + insulin (17-23 vs six events per 1,000 person-years) and was associated with increased mortality (RR 2.13 [1.97, 2.37]). There were no significant differences in risk between individual SUs in combination with insulin., Conclusions/interpretation: In combination with insulin, the use of SUs was associated with increased mortality compared with metformin. There were no significant risk differences between SUs.

Aim: Dipeptidyl peptidase-4 (DPP-4) inhibitors and glucagon-like peptide-1 (GLP-1) agonists are widely used in combinations with metformin in the treatment of type 2 diabetes; however, data on long-term safety compared with conventional combination therapies are limited., Methods: Danish individuals without prior myocardial infarction or stroke that initiated combinations of metformin with sulphonylurea (SU), DPP-4 inhibitors, GLP-1 agonists or insulin between 9 May 2007 and 31 December 2011 were followed up for the risk of all-cause mortality, cardiovascular (CV) mortality or a combined end point of myocardial infarction, stroke and CV mortality. Rate ratios (RR) were calculated using time-dependent multivariable Poisson regression analysis., Results: A total of 40 028 patients (59% men, mean age 60 ± 13 years) used metformin with SU (n = 25 092), DPP-4 inhibitor (n = 11 138), GLP-1 agonist (n = 4345) or insulin (n = 6858). Crude incidence rates per 1000 patient years for the combined end point were 18 (SU), 10 (DPP-4 inhibitor), 8 (GLP-1 agonist) and 21 (insulin). In adjusted analyses with metformin + SU as reference, metformin + DPP-4 inhibitor was associated with an RR of 0.65 (0.54-0.80) for mortality, an RR of 0.57 (0.40-0.80) for CV mortality and an RR of 0.70 (0.57-0.85) for the combined end point. For metformin + GLP-1 agonist, the RR for mortality was 0.77 (0.51-1.17), for CV mortality 0.89 (0.47-1.68), and for the combined end point 0.82 (0.55-1.21)., Conclusion: Incretin-based drugs combined with metformin were safe compared with conventional combinations of glucose-lowering therapy. Use of incretin-based therapy may be target for strategies to lower CV risk in type 2 diabetes, although it should be recognized that the multivariable analysis may not have fully accounted for important baseline differences., (© 2014 John Wiley & Sons Ltd.)

Background: Sulfonylureas have been linked to an increased cardiovascular risk by inhibition of myocardial preconditioning. Whether individual sulfonylureas affect outcomes in diabetic patients after emergent percutaneous coronary intervention for myocardial infarction is unknown., Methods: All Danish patients receiving glucose-lowering drugs admitted with myocardial infarction between 1997 and 2006 who underwent emergent percutaneous coronary intervention were identified from national registers. Multivariable Cox proportional hazards models were used to analyze the risk of cardiovascular mortality and morbidity associated with sulfonylureas., Results: A total of 926 patients were included and 163 (17.6%) patients died during the first year of which 155 (16.7%) were cardiovascular deaths. The most common treatment was sulfonylureas which were received by 271 (29.3%) patients, and 129 (13.9%) received metformin. Cox proportional hazard regression analyses adjusted for age, sex, calendar year, comorbidity and concomitant pharmacotherapy showed an increased risk of cardiovascular mortality (hazard ratio [HR] 2.91, 95% confidence interval [CI] 1.26-6.72 ; p=0.012), cardiovascular mortality and nonfatal myocardial infarction (HR 2.69 , 95% CI 1.21-6.00; p=0.016), and all-cause mortality (HR 2.46, 95% CI 1.11-5.47; p=0.027), respectively, with glyburide compared to metformin., Conclusions: Glyburide is associated with increased cardiovascular mortality and morbidity in patients with diabetes mellitus undergoing emergent percutaneous coronary intervention after myocardial infarction. Early reperfusion therapy is the mainstay in modern treatment of myocardial infarction and the time may have come to discard glyburide in favour of sulfonylureas that do not appear to confer increased cardiovascular risk., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Aims: The impact of insulin secretagogues (ISs) on long-term major clinical outcomes in type 2 diabetes remains unclear. We examined mortality and cardiovascular risk associated with all available ISs compared with metformin in a nationwide study., Methods and Results: All Danish residents >20 years, initiating single-agent ISs or metformin between 1997 and 2006 were followed for up to 9 years (median 3.3 years) by individual-level linkage of nationwide registers. All-cause mortality, cardiovascular mortality, and the composite of myocardial infarction (MI), stroke, and cardiovascular mortality associated with individual ISs were investigated in patients with or without previous MI by multivariable Cox proportional-hazard analyses including propensity analyses. A total of 107 806 subjects were included, of whom 9607 had previous MI. Compared with metformin, glimepiride (hazard ratios and 95% confidence intervals): 1.32 (1.24-1.40), glibenclamide: 1.19 (1.11-1.28), glipizide: 1.27 (1.17-1.38), and tolbutamide: 1.28 (1.17-1.39) were associated with increased all-cause mortality in patients without previous MI. The corresponding results for patients with previous MI were as follows: glimepiride: 1.30 (1.11-1.44), glibenclamide: 1.47 (1.22-1.76), glipizide: 1.53 (1.23-1.89), and tolbutamide: 1.47 (1.17-1.84). Results for gliclazide [1.05 (0.94-1.16) and 0.90 (0.68-1.20)] and repaglinide and [0.97 (0.81-1.15) and 1.29 (0.86-1.94)] were not statistically different from metformin in both patients without and with previous MI, respectively. Results were similar for cardiovascular mortality and for the composite endpoint., Conclusion: Monotherapy with the most used ISs, including glimepiride, glibenclamide, glipizide, and tolbutamide, seems to be associated with increased mortality and cardiovascular risk compared with metformin. Gliclazide and repaglinide appear to be associated with a lower risk than other ISs.

Background: Type 2 diabetes is a well-established risk factor for cardiovascular disease and is common among patients with acute myocardial infarction (MI). The extent to which patients with first-time MI develop diabetes requiring glucose-lowering medications (GLM) is largely unknown. The aim of the study was to investigate temporal trends in the initiation of GLM among patients discharged after first-time MI., Methods: All Danish residents aged ≥ 30 years without prior diabetes hospitalized with first-time MI between 1997 and 2006 were identified by individual-level-linkage of nationwide registers. Initiation of GLM during follow-up was assessed by claimed prescriptions from pharmacies. Temporal trends in initiation of GLM were assessed by incidence rate calculations in the MI population as in the general population. Multivariable Cox proportional-hazard models were used to investigate the likelihood of initiating GLM within a year post-MI., Results: The population comprised 66,788 patients. Among these patients 3962 patients initiated GLM, of whom 1567 started within one year post-MI. An increase in incidence rates of GLM initiation in the MI population from 19.6 per 1000 person years in 1997 to approximately 27.6 in 2001 was demonstrated. After 2001 the incidence rates stabilized. A similar trend was observed in the general population where the incidence rates increased from 2.8 in 1997 to 4.0 in 2004 and then stabilized., Conclusion: Our study demonstrated an increase in incidence rates of GLM initiation within the first year post- MI. A similar trend was observed in the general population suggesting that the increase in GLM among MI patients was primarily the effect of a general increased awareness of diabetes. From a public heath perspective, this study underscores a continuous need for diagnostic and therapeutic improvement in the care of MI patients that develop diabetes.

What Is Already Known About This Subject: General use of hormone replacement therapy (HRT) dropped drastically after 2002 when pivotal randomized trials showed increased risk of coronary artery disease and other complications with HRT. HRT is not recommended for primary or secondary prevention of coronary heart disease and guidelines recommend discontinuation of HRT after myocardial infarction (MI). It is unknown whether women actually discontinue HRT after MI., What This Study Adds: Women who use HRT when they experience their MI generally continue using HRT. We found a remarkably low increase in discontinuation after 2002, in contrast to the general drop in use of HRT., Aim: To characterize the pattern of use and discontinuation of postmenopausal hormone replacement therapy (HRT) in women with myocardial infarction (MI) before and after 2002, where the general use of HRT dropped drastically subsequent to the results of the Women's Health Initiative trial., Methods: All Danish women aged ≥40 years hospitalized with MI in the period 1997 to 2005 and their use of HRT were identified by individual-level-linkage of nationwide registers of hospitalization and drug dispensing from pharmacies. Characteristics associated with HRT use at time of MI and subsequent HRT discontinuation were analysed by multivariable logistic regression., Results: In the study period, 34,778 women were discharged after MI. Of these, 3979 (11.4%) received HRT at the time of MI and their most used categories of HRT were vaginal oestrogen and oral oestrogen alone (46.6% and 28.7%, respectively). The percentage of women who continued HRT during the first year after discharge was 85.0% in the period 2000-2002 and had decreased to 79.6% in the period 2003-2005. Vaginal oestrogen use was associated with overall discontinuation of HRT (odds ratio [OR] 1.37, 95% confidence interval [CI] 1.10, 1.72), whereas use of oral oestrogen alone and use of oral cyclic combined oestrogen/progestogen were associated with change of HRT after MI (OR 2.33, 95% CI 1.10, 4.93 and OR 2.94, 95% CI 1.35, 6.39, respectively)., Conclusion: The majority of women experiencing an MI during ongoing HRT continued HRT after discharge and this pattern of HRT use did not change markedly after 2002., (© 2010 The Authors. British Journal of Clinical Pharmacology © 2010 The British Pharmacological Society.)

Background: To investigate the effects of statin use over the last 10 years among diabetic patients who initiated glucose-lowering medications (GLMs) in Denmark., Methods: we identified all Danish citizens 30 years and older who claimed their first GLM between 1997 and 2006, with follow-up until 2007. Use of medications, national background, income, and hospitalizations were obtained by cross-linkage of national registries in Denmark. We analyzed factors related to initiation and interruption of statin treatment. The analyses included country of birth, citizenship and, as proxy for ethnic origin, we constructed variables based on both the subjects and on their parent's country of birth. Countries were grouped as Denmark, Western countries, Eastern countries, and Africa., Results: the cohort included 143,625 subjects. Compared with persons of Danish origin, the initiation of a statin medication during follow-up was significantly lower among patients of non-Danish origin: Odds ratio for subjects of Eastern origin 0.61 [CI 0.49-0.76] and 0.37 for subjects of African origin, [CI 0.24-0.59], both p < 0.001. The risk of interrupting statin treatment once it had been initiated was also higher in these groups (hazard ratio 2.03, [CI 1.91-2.17] for Eastern subjects and 1.94, [CI 1.63-2.32] for African subjects, both p < 0.0001). Combination of ethnic parameters to refine identification of the cohort led to the same conclusions as the analysis based only on country of birth or citizenship respectively., Conclusion: diabetes patients of African and Eastern origin in Denmark have less chance of being treated with a statin than those of western and Danish origin despite similar access to the Danish health care system.

Aims/hypothesis: The safety of metformin in heart failure has been questioned because of a perceived risk of life-threatening lactic acidosis, though recent studies have not supported this concern. We investigated the risk of all-cause mortality associated with individual glucose-lowering treatment regimens used in current clinical practice in Denmark., Methods: All patients aged ≥ 30 years hospitalised for the first time for heart failure in 1997-2006 were identified and followed until the end of 2006. Patients who received treatment with metformin, a sulfonylurea and/or insulin were included and assigned to mono-, bi- or triple therapy groups. Multivariable Cox proportional hazard regression models were used to assess the risk of all-cause mortality., Results: A total of 10,920 patients were included. The median observational time was 844 days (interquartile range 365-1,395 days). In total, 6,187 (57%) patients died. With sulfonylurea monotherapy used as the reference, adjusted hazard ratios for all-cause mortality associated with the different treatment groups were as follows: metformin 0.85 (95% CI 0.75-0.98, p = 0.02), metformin + sulfonylurea 0.89 (95% CI 0.82-0.96, p = 0.003), metformin + insulin 0.96 (95% CI 0.82-1.13, p = 0.6), metformin + insulin + sulfonylurea 0.94 (95% CI 0.77-1.15, p = 0.5), sulfonylurea + insulin 0.97 (95% CI 0.86-1.08, p = 0.5) and insulin 1.14 (95% CI 1.06-1.20, p = 0.0001)., Conclusions/interpretation: Treatment with metformin is associated with a low risk of mortality in diabetic patients with heart failure compared with treatment with a sulfonylurea or insulin.

Background: The optimum oral pharmacological treatment of diabetes mellitus to reduce cardiovascular disease and mortality following myocardial infarction has not been established. We therefore set out to investigate the association between individual oral glucose-lowering drugs and cardiovascular outcomes following myocardial infarction in patients with diabetes mellitus not treated with emergent percutaneous coronary intervention., Materials and Methods: All patients aged 30 years or older receiving glucose-lowering drugs (GLDs) and admitted with myocardial infarction (MI) not treated with emergent percutaneous coronary intervention in Denmark during 1997-2006 were identified by individual-level linkage of nationwide registries of hospitalizations and drug dispensing from pharmacies. Multivariable Cox regression models adjusted for age, sex, calendar year, comorbidity, and concomitant pharmacotherapy were used to assess differences in the composite endpoint of non-fatal MI and cardiovascular mortality between individual GLDs, using metformin monotherapy as reference., Results: The study comprised 9876 users of GLDs admitted with MI. The mean age was 72.3 years and 56.5% of patients were men. A total of 3649 received sulfonylureas and 711 received metformin at admission. The average length of follow-up was 2.2 (SD 2.6) years. A total of 6,171 patients experienced the composite study endpoint. The sulfonylureas glibenclamide, glimepiride, glipizide, and tolbutamide were associated with increased risk of cardiovascular mortality and/or nonfatal MI with hazard ratios [HRs] of 1.31 (95% confidence interval [CI] 1.17-1.46), 1.19 (1.06-1.32), 1.25 (1.11-1.42), and 1.18 (1.03-1.34), respectively, compared with metformin. Gliclazide was the only sulfonylurea not associated with increased risk compared with metformin (HR 1.03 [0.88-1.22])., Conclusions: In patients with diabetes mellitus admitted with MI not treated with emergent percutaneous coronary intervention, monotherapy treatment with the sulfonylureas glibenclamide, glimepiride, glipizide, and tolbutamide was associated with increased cardiovascular risk compared with metformin monotherapy.

Background: Patients with atrial fibrillation (AF) often require anticoagulation and platelet inhibition, but data are limited on the bleeding risk of combination therapy., Methods: We performed a cohort study using nationwide registries to identify all Danish patients surviving first-time hospitalization for AF between January 1, 1997, and December 31, 2006, and their posthospital therapy of warfarin, aspirin, clopidogrel, and combinations of these drugs. Cox proportional hazards models were used to estimate risks of nonfatal and fatal bleeding., Results: A total of 82,854 of 118,606 patients (69.9%) surviving AF hospitalization had at least 1 prescription filled for warfarin, aspirin, or clopidogrel after discharge. During mean (SD) follow-up of 3.3 (2.6) years, 13,573 patients (11.4%) experienced a nonfatal or fatal bleeding. The crude incidence rate for bleeding was highest for dual clopidogrel and warfarin therapy (13.9% per patient-year) and triple therapy (15.7% per patient-year). Using warfarin monotherapy as a reference, the hazard ratio (95% confidence interval) for the combined end point was 0.93 (0.88-0.98) for aspirin, 1.06 (0.87-1.29) for clopidogrel, 1.66 (1.34-2.04) for aspirin-clopidogrel, 1.83 (1.72-1.96) for warfarin-aspirin, 3.08 (2.32-3.91) for warfarin-clopidogrel, and 3.70 (2.89-4.76) for warfarin-aspirin-clopidogrel., Conclusions: In patients with AF, all combinations of warfarin, aspirin, and clopidogrel are associated with increased risk of nonfatal and fatal bleeding. Dual warfarin and clopidogrel therapy and triple therapy carried a more than 3-fold higher risk than did warfarin monotherapy.

Background: The majority of out-of-hospital cardiac arrests (OHCAs) occur in residential locations, but knowledge about strategic placement of automated external defibrillators in residential areas is lacking. We examined whether residential OHCA areas suitable for placement of automated external defibrillators could be identified on the basis of demographic characteristics and characterized individuals with OHCA in residential locations., Methods and Results: We studied 4828 OHCAs in Copenhagen between 1994 and 2005. The incidence and characteristics of OHCA were examined in every 100 x 100-m (109.4 x 109.4-yd) residential area according to its underlying demographic characteristics. By combining > or =2 demographic characteristics, it was possible to identify 100 x 100-m (109.4 x 109.4-yd) areas with at least 1 arrest every 5.6 years (characterized by >300 persons per area and lowest income) to 1 arrest every 4.3 years (characterized by >300 persons per area, lowest income, low education, and highest age). These areas covered 9.0% and 0.8% of all residential OHCAs, respectively. Individuals with OHCA in residential locations differed from public ones in that the patients were older (70.6 versus 60.6 years; P<0.0001), the ambulance response interval was longer (6.0 versus 5.0 minutes; P<0.0001), arrests occurred more often at night (21.2% versus 11.2%; P<0.0001), the patients had ventricular fibrillation less often (12.8% versus 38.1%; P<0.0001), and the patients had a worse 30-day survival rate (3.2% versus 13.9%; P<0.0001)., Conclusions: On the basis of simple demographic characteristics of a city center, we could identify residential areas suitable for automated external defibrillator placement. Individuals with OHCA in residential locations were more likely to have characteristics associated with poor outcome compared with public arrests.

Aims/hypothesis: We assessed secular trends of cardiovascular outcomes following first diagnosis of myocardial infarction (MI) or diabetes in an unselected population., Methods: All Danish residents aged > or = 30 years without prior diabetes or MI were identified by individual-level linkage of nationwide registers. Individuals hospitalised with MI or claiming a first-time prescription for a glucose-lowering medication (GLM) during the period from 1997 to 2006 were included. Analyses were by Poisson regression models. Primary endpoints were death by all causes, cardiovascular death and MI., Results: The study included 3,092,580 individuals, of whom 77,147 had incident MI and 118,247 new-onset diabetes. MI patients had an increased short-term risk of all endpoints compared with the general population. The rate ratio (RR) for cardiovascular death within the first year after MI was 11.1 (95% CI 10.8-11.5) in men and 14.8 (14.3-15.3) in women, respectively. The risk rapidly declined and 1 year after the index MI, RR was 2.11 (2.00-2.23) and 2.8 (2.64-2.97) in men and women, respectively. Patients with diabetes carried a constantly elevated risk of all endpoints compared with the general population. The cardiovascular death RR was 1.90 (1.77-2.04) and 1.92 (1.78-2.07) in men and women, respectively during the first year after GLM initiation., Conclusions/interpretation: Incident MI is associated with high short-term risk, which decreases rapidly over time. Incident diabetes is associated with a persistent excessive cardiovascular risk after initiation of GLM therapy. This further strengthens the necessity of early multi-factorial intervention in diabetes patients for long-term benefit.

Background: Studies have raised concern on the cardiovascular safety of nonsteroidal antiinflammatory drugs (NSAIDs). We studied safety of NSAID therapy in a nationwide cohort of healthy individuals., Methods and Results: With the use of individual-level linkage of nationwide administrative registers, we identified a cohort of individuals without hospitalizations 5 years before first prescription claim of NSAIDs and without claimed drug prescriptions for selected concomitant medication 2 years previously. The risk of cardiovascular death, a composite of coronary death or nonfatal myocardial infarction, and fatal or nonfatal stroke associated with the use of NSAIDs was estimated by case-crossover and Cox proportional hazard analyses. The entire Danish population age 10 years or more consisted of 4,614,807 individuals on January 1, 1997, of which 2,663,706 (57.8%) claimed at least 1 prescription for NSAIDs during 1997 to 2005. Of these; 1,028,437 individuals were included in the study after applying selection criteria regarding comorbidity and concomitant pharmacotherapy. Use of the nonselective NSAID diclofenac and the selective cyclooxygenase-2 inhibitor rofecoxib was associated with an increased risk of cardiovascular death (odds ratio, 1.91; 95% confidence interval, 1.62 to 2.42; and odds ratio, 1.66; 95% confidence interval, 1.06 to 2.59, respectively), with a dose-dependent increase in risk. There was a trend for increased risk of fatal or nonfatal stroke associated with ibuprofen treatment (odds ratio, 1.29; 95% confidence interval, 1.02 to 1.63), but naproxen was not associated with increased cardiovascular risk (odds ratio for cardiovascular death, 0.84; 95% confidence interval, 0.50 to 1.42)., Conclusions: Individual NSAIDs have different degrees of cardiovascular safety, which must be considered when choosing appropriate treatment. In particular, rofecoxib and diclofenac were associated with increased cardiovascular mortality and morbidity and should be used with caution in most individuals, whereas our results suggest that naproxen has a safer cardiovascular risk-profile.

Objectives: We studied the association of clopidogrel with mortality in acute myocardial infarction (AMI) patients with heart failure (HF) not receiving percutaneous coronary intervention (PCI)., Background: Use of clopidogrel after AMI is low in patients with HF, despite the fact that clopidogrel is associated with absolute mortality reduction in AMI patients., Methods: All patients hospitalized with first-time AMI (2000 through 2005) and not undergoing PCI within 30 days from discharge were identified in national registers. Patients with HF treated with clopidogrel were matched by propensity score with patients not treated with clopidogrel. Similarly, 2 groups without HF were identified. Risks of all-cause death were obtained by the Kaplan-Meier method and Cox regression analyses., Results: We identified 56,944 patients with first-time AMI. In the matched cohort with HF (n = 5,050) and a mean follow-up of 1.50 years (SD = 1.2), 709 (28.1%) and 812 (32.2%) deaths occurred in patients receiving and not receiving clopidogrel treatment, respectively (p = 0.002). The corresponding numbers for patients without HF (n = 6,092), with a mean follow-up of 2.05 years (SD = 1.3), were 285 (9.4%) and 294 (9.7%), respectively (p = 0.83). Patients with HF receiving clopidogrel demonstrated reduced mortality (hazard ratio: 0.86; 95% confidence interval: 0.78 to 0.95) compared with patients with HF not receiving clopidogrel. No difference was observed among patients without HF (hazard ratio: 0.98; 95% confidence interval: 0.83 to 1.16)., Conclusions: Clopidogrel was associated with reduced mortality in patients with HF who do not undergo PCI after their first-time AMI, whereas this association was not apparent in patients without HF. Further studies of the benefit of clopidogrel in patients with HF and AMI are warranted.

Aims: Since 2001 guidelines recommend statin treatment in most patients with diabetes. We investigated secular changes in initiation and persistence to statin treatment during a 10-year period in a nationwide cohort of patients initiating glucose-lowering medication (GLM)., Methods: All Danish citizens 30 years and older who claimed prescriptions of GLM between 1997 and 2006 were identified from nationwide registers of drug dispensing from pharmacies and hospitalizations, and followed until 2006. Statin treatment was registered if a prescription was claimed during the period. By logistic regression we analyzed factors related to initiation and persistence to statin treatment., Results: In total 128,106 patients were included. In 1997 only 7% of the patients receiving GLM claimed statins within the first year after GLM initiation. Despite increasing statin prescriptions the following years, only 62% were using statins at the end of follow up. The chance of ever receiving statins was lowest if not initiated within 180-days following the first purchase of GLM (OR 0.75, 95% CI 0.74-0.76). A previous myocardial infarction was associated with increased statin treatment (OR 4.51; 95% CI 4.31 - 4.71), while low income was associated with lower use of statins (OR 0.68; 95%CI 0.66-0.72). Between 75-85 % of the patients who initiated statins treatment were persistent to treatment by 2007., Conclusions: In spite of increasing use of statins in diabetes patients over time, many patients remain untreated. Early initiation of statin treatment in diabetic patients and focus on patients with low socioeconomic status is needed to give long-term benefits.

Background: Depression worsens the prognosis in patients with cardiac disease, and treatment with antidepressants may improve survival. Guidelines recommend use of selective serotonin reuptake inhibitors (SSRIs), but knowledge of the prognostic effect of different classes of antidepressants is sparse., Methods and Results: We studied 99 335 patients surviving first hospitalization for heart failure (HF) from 1997 to 2005. Use of HF medication and antidepressants (divided into tricyclic antidepressants [TCA] and SSRI) was determined by prescription claims. Risk of overall and cardiovascular death associated with antidepressants, HF medication, and coadministration of these 2 drug classes was estimated by Cox proportional hazard analyses. Propensity adjusted models were performed as sensitivity analysis. During the study period, there were 53 988 deaths, of which 83.0% were due to cardiovascular causes (median follow-up, 1.9 years; 5, 95% fractiles, 0.04 to 7.06 years). Use of beta-blockers was associated with decreased risk of cardiovascular death (hazard ratio [HR], 0.77; 95% CI, 0.75 to 0.79). Antidepressants were prescribed to 19 411 patients, and both TCA and SSRI were associated with increased risk of overall and cardiovascular death (TCA: HR, 1.33; CI, 1.26 to 1.40; and HR, 1.25; CI, 1.17 to 1.32; SSRI: HR, 1.37; CI, 1.34 to 1.40; and HR, 1.34; CI, 1.30 to 1.38, respectively). Coadministration of SSRI and beta-blockers was associated with a higher risk of overall and cardiovascular death compared with coadministration of beta-blockers and TCA (P for interaction <0.01)., Conclusions: Use of antidepressants in patients with HF was associated with worse prognosis. Coadministration of SSRIs and beta-blockers was associated with increased risk of overall death and cardiovascular death compared with coadministration of TCAs and beta-blockers. To further clarify this, clinical trials testing the optimal antidepressant strategy in patients with HF are warranted.

Background: Public-access defibrillation with automated external defibrillators (AEDs) is being implemented in many countries worldwide with considerable financial implications. The potential benefit and economic consequences of focused or unfocused AED deployment are unknown., Methods and Results: All cardiac arrests in public in Copenhagen, Denmark, from 1994 through 2005 were geographically located, as were 104 public AEDs placed by local initiatives. In accordance with European Resuscitation Council and American Heart Association (AHA) guidelines, areas with a high incidence of cardiac arrests were defined as those with 1 cardiac arrest every 2 or 5 years, respectively. There were 1274 cardiac arrests in public locations. According to the European Resuscitation Council or AHA guidelines, AEDs needed to be deployed in 1.2% and 10.6% of the city area, providing coverage for 19.5% (n=249) and 66.8% (n=851) of all cardiac arrests, respectively. The excessive cost of such AED deployments was estimated to be $33 100 or $41 000 per additional quality-adjusted life year, whereas unguided AED placement covering the entire city had an estimated cost of $108 700 per quality-adjusted life year. Areas with major train stations (1.8 arrests every 5 years per area), large public squares, and pedestrianized areas (0.6 arrests every 5 years per area) were main predictors of frequent cardiac arrests., Conclusions: To achieve wide AED coverage, AEDs need to be more widely distributed than recommended by the European Resuscitation Council guidelines but consistent with the American Heart Association guidelines. Strategic placement of AEDs is pivotal for public-access defibrillation, whereas with unguided initiatives, AEDs are likely to be placed inappropriately.

Aims: To examine the risk of death associated with antiarrhythmic drug (AAD) therapy in a nationwide unselected cohort of patients with atrial fibrillation (AF)., Methods and Results: All patients admitted with AF in Denmark from 1995 to 2004 and their subsequent use of AADs were identified by individual-level linkage of nationwide registries. Multivariable Cox proportional-hazard models with time-dependent covariates were used to analyse the risk of death associated with AAD therapy. A total of 141,500 patients were included in the study; of these 3356 (2.4%) patients received treatment with flecainide, 3745 (2.6%) propafenone, 23,346 (16.5%) sotalol, and 10,376 (7.3%) amiodarone. Annualized mortality rates were 2.54, 4.25, 5.29, and 7.42 per year per 100 person years for flecainide, propafenone, sotalol, and amiodarone, respectively. Multivariable Cox proportional-hazard models did not show increased risk of death associated with any of the AADs. Hazard ratio (95% confidence interval) for flecainide 0.38 (0.32-0.44), propafenone 0.65 (0.58-0.71), sotalol 0.65 (0.63-0.67), and amiodarone 0.94 (0.89-1.00)., Conclusion: In an unselected cohort of patients with AF, antiarrhythmic treatment with flecainide, propafenone, sotalol, or amiodarone was not associated with increased risk of death. From a safety perspective, this indicates appropriate selection of patients for AAD therapy.

Objective: To analyse how hospital factors influence the use of oral anticoagulants (OAC) in atrial fibrillation (AF) patients and address the clinical consequences of hospital variation in OAC use., Design and Subjects: By linkage of nationwide Danish administrative registers we conducted an observational study including all patients with a first-time hospitalization for AF between 1995 and 2004 as well as prescription claims for OAC. Multivariable logistic regression analysis was used to evaluate hospital factors associated with prescription of OAC therapy. Cox proportional-hazard models were used to estimate the risk of re-hospitalization for thromboembolism and haemorrhagic stroke with respect to discharge from a low, intermediate, or high OAC use hospital., Results: Overall 40,133 (37%) out of 108,504 patients received OAC; ranging from 17% to 50% between the hospitals with the lowest and highest OAC use, respectively. Cardiology departments had the highest use of OAC, but neither tertiary university hospitals nor high volume hospitals had higher OAC use than local community hospitals and low volume hospitals. Risk of a thromboembolic event was significantly increased amongst patients from hospitals with a low OAC use (hazard ratio 1.16, confidence interval 1.10-1.22). Notably, higher OAC use was not associated with a higher risk of haemorrhagic stroke., Conclusion: In Denmark between 1995 and 2004, there was a major hospital variation in AF patients receiving OAC, and consequently, more thromboembolic events were observed amongst patients from low OAC use hospitals. Our study emphasizes the need for a continued vigilance on implementation of international AF management guidelines.

Use of some nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with increased cardiovascular risk in several patient groups, but whether this excess risk exists in apparently healthy individuals has not been clarified. Using a historical cohort design, we estimated the risk of death and myocardial infarction associated with the use of NSAIDs. Participants in the study were selected from the Danish population and were defined as healthy according to a history of no hospital admissions and no concomitant selected pharmacotherapy. The source population consisted of 4,614,807 individuals, of whom 1,028,437 were included in the study after applying selection criteria. Compared to no NSAID use, hazard ratios (95% confidence limits) for death/myocardial infarction were 1.01 (0.96-1.07) for ibuprofen, 1.63 (1.52-1.76) for diclofenac, 0.97 (0.83-1.12) for naproxen, 2.13 (1.89-2.41) for rofecoxib, and 2.01 (1.78-2.27) for celecoxib. A dose-dependent increase in cardiovascular risk was seen for selective COX-2 inhibitors and diclofenac. Caution should be exercised in NSAID use in all individuals, and particularly high doses should be avoided if possible.

Objectives: To study differences in the clinical efficacy of various brands of beta-blocker in secondary prevention after a myocardial infarction (MI)., Methods: All patients hospitalized with a first MI between 1995 and 2002 who were still alive 30 days after discharge and had had at least one prescription for a beta-blocker filled were identified by individual-level linkage of nationwide registries of hospitalizations and drugs dispensed from pharmacies. A total of 32,259 MI patients were included in the study. Multivariable Cox proportional hazard models were used to analyze the risks of death and recurrent MI related to treatment with different beta-blockers., Results: The risks for death and recurrent MI were similar in patients using different beta-blockers, except that mortality from all causes among patients with a prescription for sotalol was higher. Subgroup analyses of high-risk patients with diabetes or congestive heart failure and of patients using comparable dosages of beta-blockers did not show effects on the risk of death or recurrent MI., Conclusion: Except for sotalol, the different types of beta-blocker had similar clinical efficacy in reducing mortality and the recurrence of MI. The equivalent efficacy remained when high-risk patients were analyzed separately., ((c) 2008 S. Karger AG, Basel.)

Purpose: To describe the nationwide pattern of use of non-steroidal anti-inflammatory drugs (NSAIDs) in the Danish population., Methods: All Danish citizens aged 10 or above 1 January 1997 were included in the study. The national prescription registry was used to identify all claimed prescriptions for NSAIDs by the cohort until 2005. By individual-level-linkage of nationwide registries, information was acquired concerning hospitalizations, comorbidity, concomitant pharmacotherapy and socioeconomic factors., Results: The population consisted of 4,614,807 individuals, of which 2,663,706 (57.8%) claimed at least one prescription for NSAID from 1997 to 2005. Ibuprofen and diclofenac were the most frequently used non-selective NSAIDs, whereas rofecoxib and celecoxib were the most frequently used selective cyclooxygenase-2 (COX-2) inhibitors. The usage was similar across all age groups. Female sex and increasing age was associated with increased use of NSAID. Factors predicting extensive NSAID use were: rheumatic disease (odds ratio (OR) = 1.79, 95% confidence interval (CI): 1.69-1.90), gout agents (allopurinol) (OR = 2.54, CI: 2.44-2.64) and other pain medication (OR = 3.27, CI: 3.23-3.31). NSAIDs were most often prescribed for use for one distinct treatment interval and for a short period (overall inter-quartile range [IQR]: 9-66 days). High doses were used in a relatively large proportion of the population (8.9% for etodolac to 19.5% for celecoxib) and 54,373 (2.0%) claimed prescriptions for more than one NSAID at the same time., Conclusion: NSAIDs were commonly used in the Danish population. Since NSAIDs have been associated with increased cardiovascular risk, further research on the overall risk associated with these drugs on a national scale is needed.

Aims: To study evolvement in pharmacotherapy of atrial fibrillation from 1995 to 2004., Methods and Results: All Danish patients were discharged following first-time atrial fibrillation and their pharmacotherapy was identified by individual-level-linkage of nationwide registers of hospitalization and drug dispensing from pharmacies. A total of 108 791 patients survived 30 days after discharge and were included. In 1995-1996, 7.4% of the patients received beta-blockers, increasing to 44.3% in 2003-2004. The corresponding figures for amiodarone were 2.9 and 5.4%. In contrast, use of nondihydropyridine calcium-channel blockers, digoxin, sotalol, and class 1C antiarrhythmics decreased from 20.6, 63.9, 21.3, and 4.0% in 1995-1996 to 12.6, 43.8, 4.2, and 1.3% in 2003-2004, respectively. Notably, patients receiving anticoagulants increased from 29.8 to 43.5%. Multivariate logistic regression analysis revealed females to be associated with more use of digoxin, but less use of amiodarone and oral anticoagulants than males. Patients above 80 years received less pharmacotherapy, apart from digoxin treatment that was more commonly used in elderly., Conclusion: Pharmacotherapy of atrial fibrillation has changed towards increased beta-blocker use with a coincident decrease in the use of other rate-limiting drugs and sotalol. Treatment with amiodarone or class 1C antiarrhythmics remained very low. Oral anticoagulant therapy increased considerably, but women and elderly were apparently undertreated.

What Is Already Known About This Subject: Treatment with an angiotensin-converting enzyme (ACE) inhibitor benefits many patients with cardiovascular disease. ACE inhibitors are generally assumed to be equally effective, but this has never been fully verified in clinical trials., What This Study Adds: Studying the association among ACE inhibitors after myocardial infarction demonstrated similarity in clinical outcome and supports a dosage-response relationship. Therefore, for long-term benefits for patients who need treatment with an ACE inhibitor, a focus of treatment at the recommended dosage is most important and not which ACE inhibitor is used., Aim: Therapy with angiotensin-converting enzyme (ACE) inhibitors is common after myocardial infarction (MI). Given the lack of randomized trials comparing different ACE inhibitors, the association among ACE inhibitors after MI in risk for mortality and reinfarction was studied., Methods: Patients hospitalized with first-time MI (n = 16,068) between 1995 and 2002, who survived at least 30 days after discharge and claimed at least one prescription of ACE inhibitor, were identified using nationwide administrative registries in Denmark., Results: Adjusted Cox regression analysis demonstrated no differences in risk for all-cause mortality, but patients using captopril had higher risk of reinfarction (hazard ratio 1.18, 95% confidence interval 1.05, 1.34). However, following adjustment for differences in used dosages, all ACE inhibitors had similar clinical efficacy. Risk of all-cause mortality: trandolapril (reference) 1.00, ramipril 0.97 (0.89, 1.05), enalapril 1.04 (0.95, 1.150), captopril 0.95 (0.83, 1.08), perindopril 0.98 (0.84, 1.15) and other ACE inhibitors or angiotensin II receptor blockers (ARB) 1.06 (0.94, 1.19). Reinfarction: trandolapril (reference) 1.00, ramipril 0.98 (0.89, 1.08), enalapril 1.04 (0.92, 1.17), captopril 1.05 (0.89, 1.25), perindopril 0.96 (0.81, 1.14) and other ACE inhibitors or ARB 0.99 (0.86, 1.14). Furthermore, the association between ARBs and clinical events was similar to ACE inhibitors (trandolapril reference): all-cause mortality 0.99 (0.84, 1.16) and recurrent MI 0.99 (0.83, 1.19)., Conclusions: Our results suggest a class effect among ACE inhibitors when used in comparable dosages. Focus on treatment at the recommended dosage is therefore most important, and not which ACE inhibitor is used.

Objective: To study the initiation of and long-term refill persistency with statins and beta-blockers after acute myocardial infarction (AMI) according to income and education., Design and Setting: Linkage of individuals through national registers of hospitalisations, drug dispensation, income and education., Participants: 30 078 patients aged 30-74 years surviving first hospitalisation for AMI in Denmark between 1995 and 2001., Main Outcome Measures: Initiation of statin or beta-blocker treatment (out-patient claim of prescriptions within 6 months of discharge) and refill persistency (first break in treatment lasting at least 90 days, and re-initiation of treatment after a break)., Results: When simultaneously estimating the effect of income and education on initiation of treatment, the effect of education attenuated and a clear income gradient remained for both drugs. Among patients aged 30-64 years, high income (adjusted hazard ratio (HR) 1.27; 95% confidence interval (CI) 1.19-1.35) and medium income (HR 1.13; 95% CI 1.06-1.20) was associated with initiation of statin treatment compared with low income. The risk of break in statin treatment was lower for patients with high (HR 0.73; 95% CI 0.66-0.82) and medium (HR 0.82; 95% CI 0.74-0.92) income compared with low income, whereas there was a trend in the opposite direction concerning a break in beta-blocker treatment. There was no gradient in re-initiation of treatment., Conclusion: Patients with low compared with high income less frequently initiated preventive treatment post-AMI, had worse long-term persistency with statins, but tended to have better persistency with beta-blockers. Low income by itself seems not to be associated with poor long-term refill persistency post-AMI.

Background: Use of invasive revascularization [percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG)] after acute myocardial infarction (AMI) in Denmark increased between 1996 and 2004. We investigated how this affected socioeconomic differences in their use., Materials and Methods: All patients aged 30-74 years in hospital for a first AMI in Denmark between 1996 and 2004 were included. Cox proportional hazard models were used to estimate the association between individual income (tertiles) and education (>12, 10-12 and <10 years) and time to revascularization within 6 months. Revascularization was stratified into CABG, acute PCI (within 2 days of admission) and non-acute PCI (after the third day)., Results: A total of 38,803 patients were included. In 1996-1998, 6.8% received CABG, 9.3% non-acute PCI and 2.4% acute PCI; in 2002-2004, these numbers were 11.8, 36.1 and 29.1%. CABG was more likely to be performed for patients with a high income [hazard ratio (HR), 1.18; 95% confidence interval (CI), 1.08-1.28] or a medium income (HR, 1.16; 95% CI, 1.07-1.25) than for those with a low income throughout the period. A similar income gradient was seen for non-acute PCI, but not for acute PCI, for which no gradient was seen. No educational gradient was found for CABG, and that for non-acute and acute PCI decreased during the period; by the end of the period, more patients with low than high education received acute PCI., Conclusion: In the universal health care system of Denmark, income differences in CABG and non-acute PCI persisted, whereas no such differences were seen for acute PCI.

Background: Undertreatment with recommended pharmacotherapy is a common problem in heart failure and may influence prognosis. We studied initiation and persistence of evidence-based pharmacotherapy in 107,092 patients discharged after first hospitalization for heart failure in Denmark from 1995 to 2004., Methods and Results: Prescriptions of dispensed medication and mortality were identified by an individual-level linkage of nationwide registers. Inclusion was irrespective of left ventricular function. Treatment with renin-angiotensin inhibitors (eg, angiotensin-converting enzyme inhibitors and angiotensin-2 receptor blockers), beta-blockers, spironolactone, and statins was initiated in 43%, 27%, 19%, and 19% of patients, respectively. Patients who did not initiate treatment within 90 days of discharge had a low probability of later treatment initiation. Treatment dosages were in general only 50% of target dosages and were not increased during long-term treatment. Short breaks in therapy were common, but most patients reinitiated treatment. Five years after initiation of treatment, 79% patients were still on renin-angiotensin inhibitors, 65% on beta-blockers, 56% on spironolactone, and 83% on statins. Notably, multiple drug treatment and increased severity of heart failure was associated with persistence of treatment. Nonpersistence with renin-angiotensin inhibitors, beta-blockers, and statins was associated with increased mortality with hazard ratios for death of 1.37 (95% CI, 1.31 to 1.42), 1.25 (95% CI, 1.19 to 1.32), 1.88 (95% CI, 1.67 to 2.12), respectively., Conclusions: Persistence of treatment was high once medication was started, but treatment dosages were below recommended dosages. Increased severity of heart failure or increased number of concomitant medications did not worsen persistence, but nonpersistence identified a high-risk population of patients who required special attention. A focused effort on early treatment initiation, appropriate dosages, and persistence with the regimen is likely to provide long-term benefit.