Administrative discharge codes are widely used in epidemiology, but the specificity and sensitivity of this coding is unknown and must be validated. We assessed the validity of the discharge diagnosis of syncope in administrative registers and reviewed the etiology of syncope after workup.
Two samples were investigated. One sample consisted of 5262 randomly selected medical patients. The other sample consisted of 750 patients admitted or seen in the emergency department (ED) for syncope (ICD-10: R55.9) in three hospitals in Denmark. All charts were reviewed for baseline characteristics and to confirm the presence/absence of syncope and to compare with the administrative coding. In a sample of 600 admitted patients 570 (95%) and of 150 patients from ED 140 (93%) had syncope representing the positive predictive values. Median age of the population was 69 years (IQR: ± 14). In the second sample of 5262 randomly selected medical patients, 75 (1.4%) had syncope, of which 47 were coded as R55.9 yielding a sensitivity of 62.7%, a negative predictive value of 99.5%, and a specificity of 99.9%.
ED and hospital discharge diagnostic coding for syncope has a positive predictive value of 95% and a sensitivity of 63%.
An increasing number of octogenarians are being subjected to coronary artery bypass grafting (CABG). The purpose of this study was to examine age-dependent trends in postoperative mortality and preoperative comorbidity over time following CABG.
All patients who underwent isolated CABG surgery between January 1996 and December 2012 in Denmark were included. Patients were identified through nationwide administrative registers. Age was categorized into five different groups and time into three periods to see if mortality and preoperative comorbidity had changed over time. Predictors of 30-day mortality were analysed in a multivariable Cox proportional-hazard models and survival at 1 and 5 years was estimated by Kaplan-Meier curves.
A total of 38 830 patients were included; the median age was 65.4 ± 9.5 years, increasing over time to 66.6 ± 9.5 years. Males comprised 80%. The number of octogenarians was 1488 (4%). The median survival was 14.7 years (60-69 years), 10.7 years (70-74 years), 8.9 years (75-79 years) and 7.2 years (=80 years). The 30-day mortality rate was 3%, increasing with age (1% in patients 80 years), respectively. The proportion of patients >75 years increased from 10 to 20% during the study period as well as the proportion of patients undergoing urgent or emergency surgery. The burden of comorbidities increased over time, e.g. congestive heart failure 13-17%, diabetes 12-21%, stroke 9-11%, in all age groups. Age and emergency surgery were the main predictors of 30-day mortality: age >80 years [hazard ratio (HR): 5.75, 95% confidence interval (CI): 4.41-7.50], emergency surgery (HR: 5.23, 95% CI: 4.38-6.25).
Patients are getting older at the time of surgery and have a heavier burden of comorbidities than before. The proportion of patients undergoing urgent or emergency surgery increased with age and over time. Despite this, the 30-day mortality decreased over time and long-term survival increased, except in octogenarians where it was stable. Octogenarians had substantially higher 30-day mortality compared with younger patients but surgery can be performed with acceptable risks and good long-term outcomes.
The revised cardiac risk index (RCRI) holds a central role in preoperative cardiac risk stratification in noncardiac surgery. Its performance in unselected populations, including different age groups, has, however, not been systematically investigated. We assessed the relationship of RCRI with major adverse cardiovascular events in an unselected cohort of patients undergoing elective, noncardiac surgery overall and in different age groups.
We followed up all individuals = 25 years who underwent major elective noncardiac surgery in Denmark (January 1, 2005, to November 30, 2011) for the 30-day risk of major adverse cardiovascular events (ischemic stroke, myocardial infarction, or cardiovascular death). There were 742 of 357,396 (0.2%), 755 of 74.889 (1.0%), 521 of 11,921 (4%), and 257 of 3146 (8%) major adverse cardiovascular events occurring in RCRI classes I, II, III, and IV. Multivariable odds ratio estimates were as follows: ischemic heart disease 3.30 (95% confidence interval, 2.96-3.69), high-risk surgery 2.70 (2.46-2.96), congestive heart failure 2.65 (2.29-3.06), cerebrovascular disease 10.02 (9.08-11.05), insulin therapy 1.62 (1.37-1.93), and kidney disease 1.45 (1.33-1.59). Modeling RCRI classes as a continuous variable, C statistic was highest among age group 56 to 65 years (0.772) and lowest for those aged >85 years (0.683). Sensitivity of RCRI class >I (ie, having = 1 risk factor) for capturing major adverse cardiovascular events was 59%, 71%, 64%, 66%, and 67% in patients aged = 55, 56 to 65, 66 to 75, 76 to 85, and >85 years, respectively; the negative predictive values were >98% across all age groups.
In a nationwide unselected cohort, the performance of the RCRI was similar to that of the original cohort. Having = 1 risk factor was of moderate sensitivity, but high negative predictive value for all ages.
The cumulative burden and importance of cardiovascular risk factors have changed over the past decades. Specifically, obesity rates have increased among younger people, whereas cardiovascular health has improved in the elderly. Little is known regarding how these changes have impacted the incidence and the mortality rates of heart failure. Therefore, we aimed to investigate the age-specific trends in the incidence and 1-year mortality rates following a first-time diagnosis of heart failure in Denmark between 1995 and 2012.
We included all Danish individuals >18 years of age with a first-time in-hospital diagnosis of heart failure. Data were collected from 3 nationwide Danish registries. Annual incidence rates of heart failure and 1-year standardized mortality rates were calculated under the assumption of a Poisson distribution.
We identified 210?430 individuals with a first-time diagnosis of heart failure between 1995 and 2012; the annual incidence rates per 10?000 person-years declined among older individuals (rates in 1995 versus 2012: 164 versus 115 in individuals >74 years, 63 versus 35 in individuals 65-74 years, and 20 versus 17 in individuals 55-64 years; P50 years of age, and 1.52 (95% confidence interval, 1.33-1.73; P50 years), but increased among younger (=50 years) individuals. These observations may portend a rising burden of heart failure in the community.
Severe hypokalaemia can aggravate arrhythmia tendency and prognosis, but less is known about risk of mild hypokalaemia, which is a frequent finding. We examined the associations between mild hypokalaemia and ambulatory cardiac arrhythmias and their prognosis.
Subjects from the cohort of the 'Copenhagen Holter Study' (n = 671), with no history of manifest cardiovascular (CV) disease or stroke, were studied. All had laboratory tests and 48-h ambulatory electrocardiogram (ECG) recording. The median follow-up was 6.3 years. p-Potassium was inversely associated with frequency of premature ventricular complexes (PVCs) especially in combination with diuretic treatment (r = -0.22, P = 0.015). Hypokalaemia was not associated with supraventricular arrhythmias. Subjects at lowest quintile of p-potassium (mean 3.42, range 2.7-3.6 mmol/L) were defined as hypokalaemic. Cardiovascular mortality was higher in the hypokalaemic group (hazard ratio and 95% confidence intervals: 2.62 (1.11-6.18) after relevant adjustments). Hypokalaemia in combination with excessive PVC worsened the prognosis synergistically; event rates: 83 per 1000 patient-year in subjects with both abnormalities, 10 and 15 per 1000 patient-year in those with one abnormality, and 3 per 1000 patient-year in subjects with no abnormality. One variable combining hypokalaemia with excessive supraventricular arrhythmias gave similar results in univariate analysis, but not after multivariate adjustments.
In middle-aged and elderly subjects with no manifest heart disease, mild hypokalaemia is associated with increased rate of ventricular but not supraventricular arrhythmias. Hypokalaemia interacts synergistically with increased ventricular ectopy to increase the risk of adverse events.
Since the initial description in 2010 of anoctamin 5 deficiency as a cause of muscular dystrophy, a handful of papers have described this disease in cases of mixed populations. We report the first large regional study and present data on new aspects of prevalence, muscular and cardiac phenotypic characteristics, and muscle protein expression. All patients in our neuromuscular unit with genetically unclassified, recessive limb girdle muscular dystrophy (LGMD2), Miyoshi-type distal myopathy (MMD) or persistent asymptomatic hyperCK-emia (PACK) were assessed for mutations in the ANO5 gene. Genetically confirmed patients were evaluated with muscular and cardiopulmonary examination. Among 40 unclassified patients (28 LGMD2, 5 MMD, 7 PACK), 20 were homozygous or compound heterozygous for ANO5 mutations, (13 LGMD2, 5 MMD, 2 PACK). Prevalence of ANO5 deficiency in Denmark was estimated at 1:100.000 and ANO5 mutations caused 11 % of our total cohort of LGMD2 cases making it the second most common LGMD2 etiology in Denmark. Eight patients complained of dysphagia and 3 dated symptoms of onset in childhood. Cardiac examinations revealed increased frequency of premature ventricular contractions. Four novel putative pathogenic mutations were discovered. Total prevalence and distribution of phenotypes of ANO5 disease in a representative regional cohort are described for the first time. A high prevalence of ANO5 deficiency was found among patients with unclassified LGMD2 (46 %) and MMD (100 %). The high incidence of reported dysphagia is a new phenotypic feature not previously reported, and cardiac investigations revealed that ANO5-patients may have an increased risk of ventricular arrhythmia.
To examine the risk of death associated with antiarrhythmic drug (AAD) therapy in a nationwide unselected cohort of patients with atrial fibrillation (AF).
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).
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.
The aim of this study was to investigate the impact of atrial fibrillation (AF) and antithrombotic treatment on the prognosis in patients with heart failure (HF) as well as vascular disease.
HF, vascular disease, and AF are pathophysiologically related, and understanding antithrombotic treatment for these conditions is crucial.
In hospitalized patients with HF and coexisting vascular disease (coronary artery disease or peripheral arterial disease) followed from 1997 to 2009, AF status was categorized as prevalent AF, incident AF, or no AF. Risk of thromboembolism (TE), myocardial infarction (MI), and serious bleeding was assessed by Cox regression models (hazard ratio [HR] with 95% confidence interval [CI]) with antithrombotic therapy and AF as time-dependent variables.
A total of 37,464 patients were included (age, 74.5 ± 10.7 years; 36.3% females) with a mean follow-up of 3 years during which 20.7% were categorized as prevalent AF and 17.2% as incident AF. Compared with vitamin K antagonist (VKA) in prevalent AF, VKA plus antiplatelet was not associated with a decreased risk of TE (HR: 0.91; 95% CI: 0.73 to 1.12) or MI (HR: 1.11; 95% CI: 0.96 to 1.28), whereas bleeding risk was significantly increased (HR: 1.31; 95% CI: 1.09 to 1.57). Corresponding estimates for incident AF were HRs of 0.77 (95% CI: 0.56 to 1.06), 1.07 (95% CI: 0.89 to 1.28), and 2.71 (95% CI: 1.33 to 2.21) for TE, MI, and bleeding, respectively. In no AF patients, no statistical differences were seen between antithrombotic therapies in TE or MI risk, whereas bleeding risk was significantly increased for VKA with and without single-antiplatelet therapy.
In AF patients with coexisting HF and vascular disease, adding single-antiplatelet therapy to VKA therapy is not associated with additional benefit in thromboembolic or coronary risk, but notably increased bleeding risk.
Comment In: J Am Coll Cardiol. 2014 Jun 24;63(24):2699-70124794117
Clinical guidelines have been criticized for encouraging the use of ß-blockers in noncardiac surgery despite weak evidence. Relevant clinical trials have been small and have not convincingly demonstrated an effect of ß-blockers on hard end points (ie, perioperative myocardial infarction, ischemic stroke, cardiovascular death, and all-cause death).
To assess the association of ß-blocker treatment with major cardiovascular adverse events (MACE) and all-cause mortality in patients with ischemic heart disease undergoing noncardiac surgery. DESIGN, SETTING, PARTICIPANTS, AND EXPOSURE: Individuals with ischemic heart disease with or without heart failure (HF) and with and without a history of myocardial infarction undergoing noncardiac surgery between October 24, 2004, and December 31, 2009, were identified from nationwide Danish registries. Adjusted Cox regression models were used to calculate the 30-day risks of MACE (ischemic stroke, myocardial infarction, or cardiovascular death) and all-cause mortality associated with ß-blocker therapy.
Thirty-day risk of MACE and all-cause mortality.
Of 28,263 patients with ischemic heart disease undergoing surgery, 7990 (28.3%) had HF and 20,273 (71.7%) did not. ß-Blockers were used in 4262 (53.3%) with and 7419 (36.6%) without HF. Overall, use of ß-blockers was associated with a hazard ratio (HR) of 0.90 (95% CI, 0.79-1.02) for MACE and 0.95 (0.85-1.06) for all-cause mortality. Among patients with HF, use of ß-blockers was associated with a significantly lower risk of MACE (HR, 0.75; 95% CI, 0.70-0.87) and all-cause mortality (0.80; 0.70-0.92), whereas among patients without HF, there was no significant association of ß-blocker use with MACE (1.11; 0.92-1.33) or mortality (1.15; 0.98-1.35) (P
Pharmacodynamic studies have shown that persistently high platelet reactivity is common in patients with diabetes in spite of clopidogrel treatment. Clinical trials have not convincingly demonstrated that clopidogrel benefits patients with diabetes as much patients without diabetes.
To estimate the clinical effectiveness associated with clopidogrel treatment after myocardial infarction (MI) in patients with diabetes.
By individual-level linkage of the Danish nationwide administrative registries between 2002-2009, patients who were hospitalized with incident MI and who had survived and not undergone coronary artery bypass surgery 30 days after discharge were followed up for as long as 1 year (maximally until December 31, 2009). Adjusted for age, sex, comorbidity, calendar year, concomitant pharmacotherapy, and invasive interventions, hazard ratios that were associated with clopidogrel in patients with and without diabetes were analyzed by Cox proportional-hazard models and propensity score-matched models.
All-cause mortality, cardiovascular mortality, and a composite end point of recurrent MI and all-cause mortality.
Of the 58,851 patients included in the study, 7247 (12%) had diabetes and 35,380 (60%) received clopidogrel. In total, 1790 patients (25%) with diabetes and 7931 patients (15%) without diabetes met the composite end point. Of these, 1225 (17%) with and 5377 (10%) without diabetes died. In total, 978 patients (80%) with and 4100 patients (76%) without diabetes died of events of cardiovascular origin. For patients with diabetes who were treated with clopidogrel, the unadjusted mortality rates (events/100 person-years) were 13.4 (95% CI, 12.8-14.0) vs 29.3 (95% CI, 28.3-30.4) for those not treated. For patients without diabetes who were treated with clopidogrel, the unadjusted mortality rates were 6.4 (95% CI, 6.3-6.6) vs 21.3 (95% CI, 21.0-21.7) for those not treated. However, among patients with diabetes vs those without diabetes, clopidogrel was associated with less effectiveness for all-cause mortality (HR, 0.89 [95% CI, 0.79-1.00] vs 0.75 [95% CI, 0.70-0.80]; P for interaction, .001) and for cardiovascular mortality (HR, 0.93 [95% CI, 0.81-1.06] vs 0.77 [95% CI, 0.72-0.83]; P for interaction, .01) but not for the composite end point (HR, 1.00 [95% CI, 0.91-1.10] vs 0.91 [95% CI, 0.87-0.96]; P for interaction, .08). Propensity score-matched models gave similar results.
Among patients with diabetes compared with patients without diabetes, the use of conventional clopidogrel treatment after MI was associated with lower reduction in the risk of all-cause death and cardiovascular death.
Comment In: JAMA. 2012 Sep 5;308(9):921-222948703
Comment In: JAMA. 2012 Dec 19;308(23):2456; author reply 245723288024
Comment In: JAMA. 2012 Dec 19;308(23):245723288044