Niklas Hammar

Stroke in paroxysmal atrial fibrillation: report from the Stockholm Cohort of Atrial Fibrillation

AIMS Knowledge about stroke risk in paroxysmal atrial fibrillation (PxAF) is limited. Although current guideline recommendations advocate the same treatment as in permanent atrial fibrillation (PermAF), most patients with PxAF do not receive prophylactic anticoagulation. The aim of this study is to investigate whether there are differences in stroke risk between PxAF and PermAF. METHODS AND RESULTS All patients with PxAF (n = 855) and PermAF (n = 1126) treated for atrial fibrillation (AF) during 2002 at one of Scandinavias largest hospitals were followed-up for 3.6 years regarding incidence of stroke. Information about type of AF, comorbidity, medication, and clinical events during follow-up was acquired from medical records and the National Register of Hospital Discharges. The incidence of ischaemic stroke was similar in PxAF and PermAF (26 vs. 29 events/1000 patient years). The multivariable-adjusted hazard ratio (HR) for ischaemic stroke in PxAF compared with PermAF was 1.07 (95% CI 0.71-1.61) in subjects without prior stroke. The corresponding HR for any stroke, ischaemic or haemorrhagic, was 0.89 (95% CI 0.61-1.30). Compared with the general population, ischaemic stroke was twice as common as expected in PxAF after standardization for age and sex (standardized incidence ratio 2.12, 95% CI 1.52-2.71). PxAF patients who took warfarin had approximately half as many ischaemic strokes as those who did not take warfarin (HR 0.44, 95% CI 0.30-0.65). CONCLUSION Ischaemic stroke is about as common in PxAF as in PermAF, and about twice as common as in the general population. Yet, PxAF patients do not receive protective anticoagulant treatment as often as patients with PermAF do. It is therefore important to increase the use of anticoagulants among PxAF patients in accordance with current guideline recommendations.

High effort, low reward, and cardiovascular risk factors in employed Swedish men and women: baseline results from the WOLF Study.

STUDY OBJECTIVE: To examine associations between measures of work stress (that is, the combination of high effort and low reward) and cardiovascular risk factors. DESIGN: Cross sectional first screening of a prospective cohort study. SETTING AND PARTICIPANTS: The study was conducted among 5720 healthy employed men and women living in the greater Stockholm area aged 19-70 years. All analyses were restricted to subjects with complete data (n = 4958). The investigation of associations between indicators of effort-reward imbalance and cardiovascular risk factors was restricted to the age group 30-55 years (n = 3427). MAIN RESULTS: Subjects reporting high effort and low reward at work had a higher prevalence of well known risk factors for coronary heart disease. After adjustment for relevant confounders, associations between a measure of extrinsic effort and reward (the effort-reward ratio) and hypertension (multivariate prevalence odds ratio (POR) 1.62-1.68), increased total cholesterol (upper tertile 220 mg/dl)(POR = 1.24) and the total cholesterol/high density lipoprotein(HDL)-cholesterol ratio (upper tertile 4.61)(POR 1.26-1.30) were found among men. Among women a measure of high intrinsic effort (immersion) was related to increased low density lipoprotein (LDL)-cholesterol (upper tertile 130 mg/dl)(POR 1.37-1.39). Analyses of variance showed increasing mean values of LDL cholesterol with an increasing degree of the effort-reward ratio among men and increased LDL-cholesterol among women with high levels of intrinsic effort (upper tertile of immersion). CONCLUSIONS: Findings lend support to the hypothesis that effort-reward imbalance represents a specific constellation of stressful experience at work related to cardiovascular risk. The relation was not explained by relevant confounders (for example, lack of physical exercise, body weight, cigarette smoking).

Alcohol consumption and type 2 diabetes

To clarify the relationship between alcohol consumption and type 2 diabetes we conducted a meta-analysis of published epidemiological studies. Data from 13 cohorts were included in the analysis. The results of these studies are consistent with regard to moderate alcohol consumption, indicating a protective effect in the order of 30% (relative risk [RR]meta=0.72, 95% CI=0.67–0.77). The reduced risk is seen in men as well as in women, although few studies investigated women. No protective effect of high alcohol consumption was seen and one cannot rule out that large intakes of alcohol may increase the risk of type 2 diabetes. Results from published studies suggest a U-shaped relationship between alcohol and type 2 diabetes, but this is based on rather few studies with heterogeneous design and definitions. It seems important to further investigate if, and to what extent, high alcohol consumption increases the risk of type 2 diabetes. Aspects of moderate alcohol consumption also need further investigation; these include type of drink, frequency of drinking, sex and ethnic differences.

Lower Risk of Heart Failure and Death in Patients Initiated on Sodium-Glucose Cotransporter-2 Inhibitors Versus Other Glucose-Lowering Drugs: The CVD-REAL Study (Comparative Effectiveness of Cardiovascular Outcomes in New Users of Sodium-Glucose Cotransporter-2 Inhibitors)

Background -Reduction in cardiovascular death and hospitalization for heart failure (HHF) was recently reported with the sodium-glucose co-transporter-2 inhibitor (SGLT-2i) empagliflozin in type 2 diabetes patients with atherosclerotic cardiovascular disease. We compared HHF and death in patients newly initiated on any SGLT-2i versus other glucose lowering drugs (oGLDs) in six countries to determine if these benefits are seen in real-world practice, and across SGLT-2i class. Methods -Data were collected via medical claims, primary care/hospital records and national registries from the US, Norway, Denmark, Sweden, Germany and the UK. Propensity score for SGLT-2i initiation was used to match treatment groups. Hazard ratios (HRs) for HHF, death and their combination were estimated by country and pooled to determine weighted effect size. Death data were not available for Germany. Results -After propensity matching, there were 309,056 patients newly initiated on either SGLT-2i or oGLD (154,528 patients in each treatment group). Canagliflozin, dapagliflozin, and empagliflozin accounted for 53%, 42% and 5% of the total exposure time in the SGLT-2i class, respectively. Baseline characteristics were balanced between the two groups. There were 961 HHF cases during 190,164 person-years follow up (incidence rate [IR] 0.51/100 person-years). Of 215,622 patients in the US, Norway, Denmark, Sweden, and UK, death occurred in 1334 (IR 0.87/100 person-years), and HHF or death in 1983 (IR 1.38/100 person-years). Use of SGLT-2i, versus oGLDs, was associated with lower rates of HHF (HR 0.61; 95% CI 0.51-0.73; p<0.001); death (HR 0.49; 95% CI 0.41-0.57; p<0.001); and HHF or death (HR 0.54; 95% CI 0.48-0.60, p<0.001) with no significant heterogeneity by country. Conclusions -In this large multinational study, treatment with SGLT-2i versus oGLDs was associated with a lower risk of HHF and death, suggesting that the benefits seen with empagliflozin in a randomized trial may be a class effect applicable to a broad population of T2D patients in real-world practice (NCT02993614). Clinical Trial Registration -URL: ClinicalTrials.gov; Unique Identifier: NCT02993614.Background: Reduction in cardiovascular death and hospitalization for heart failure (HHF) was recently reported with the sodium-glucose cotransporter-2 inhibitor (SGLT-2i) empagliflozin in patients with type 2 diabetes mellitus who have atherosclerotic cardiovascular disease. We compared HHF and death in patients newly initiated on any SGLT-2i versus other glucose-lowering drugs in 6 countries to determine if these benefits are seen in real-world practice and across SGLT-2i class. Methods: Data were collected via medical claims, primary care/hospital records, and national registries from the United States, Norway, Denmark, Sweden, Germany, and the United Kingdom. Propensity score for SGLT-2i initiation was used to match treatment groups. Hazard ratios for HHF, death, and their combination were estimated by country and pooled to determine weighted effect size. Death data were not available for Germany. Results: After propensity matching, there were 309 056 patients newly initiated on either SGLT-2i or other glucose-lowering drugs (154 528 patients in each treatment group). Canagliflozin, dapagliflozin, and empagliflozin accounted for 53%, 42%, and 5% of the total exposure time in the SGLT-2i class, respectively. Baseline characteristics were balanced between the 2 groups. There were 961 HHF cases during 190 164 person-years follow-up (incidence rate, 0.51/100 person-years). Of 215 622 patients in the United States, Norway, Denmark, Sweden, and the United Kingdom, death occurred in 1334 (incidence rate, 0.87/100 person-years), and HHF or death in 1983 (incidence rate, 1.38/100 person-years). Use of SGLT-2i, versus other glucose-lowering drugs, was associated with lower rates of HHF (hazard ratio, 0.61; 95% confidence interval, 0.51–0.73; P<0.001); death (hazard ratio, 0.49; 95% confidence interval, 0.41–0.57; P<0.001); and HHF or death (hazard ratio, 0.54; 95% confidence interval, 0.48–0.60; P<0.001) with no significant heterogeneity by country. Conclusions: In this large multinational study, treatment with SGLT-2i versus other glucose-lowering drugs was associated with a lower risk of HHF and death, suggesting that the benefits seen with empagliflozin in a randomized trial may be a class effect applicable to a broad population of patients with type 2 diabetes mellitus in real-world practice. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02993614.

Incidence of cancer among Nordic airline pilots over five decades: occupational cohort study

Abstract Objective: To assess the incidence of cancer among male airline pilots in the Nordic countries, with special reference to risk related to cosmic radiation. Design: Retrospective cohort study, with follow up of cancer incidence through the national cancer registries. Setting: Denmark, Finland, Iceland, Norway, and Sweden. Participants: 10 032 male airline pilots, with an average follow up of 17 years. Main outcome measures: Standardised incidence ratios, with expected numbers based on national cancer incidence rates; dose-response analysis using Poisson regression. Results: 466 cases of cancer were diagnosed compared with 456 expected. The only significantly increased standardised incidence ratios were for skin cancer: melanoma 2.3 (95% confidence interval 1.7 to 3.0), non-melanoma 2.1 (1.7 to 2.8), basal cell carcinoma 2.5 (1.9 to 3.2). The relative risk of skin cancers increased with the estimated radiation dose. The relative risk of prostate cancer increased with increasing number of flight hours in long distance aircraft. Conclusions: This study does not indicate a marked increase in cancer risk attributable to cosmic radiation, although some influence of cosmic radiation on skin cancer cannot be entirely excluded. The suggestion of an association between number of long distance flights (possibly related to circadian hormonal disturbances) and prostate cancer needs to be confirmed.

Coffee consumption, type 2 diabetes and impaired glucose tolerance in Swedish men and women.

Objectives.  The association between coffee consumption, type 2 diabetes and impaired glucose tolerance was examined. In addition, indicators of insulin sensitivity and β‐cell function according to homeostasis model assessment were studied in relation to coffee consumption.

Uric acid and risk of myocardial infarction, stroke and congestive heart failure in 417 734 men and women in the Apolipoprotein MOrtality RISk study (AMORIS)

Objectives.  Few studies have simultaneously analysed the influence of elevated serum uric acid (UA) on acute myocardial infarction (AMI), ischaemic and haemorrhagic stroke (IS, HS) and congestive heart failure (CHF) in large healthy populations. We, here, examine UA as a risk factor for AMI, stroke and CHF by age and gender in the Apolipoprotein MOrtality RISk (AMORIS) Study.

Myocardial infarction among women with early-stage breast cancer treated with conservative surgery and breast irradiation

PURPOSE To assess the possible impact of the irradiation on the risk of acute myocardial infarction among breast cancer patients treated with conservative surgery and postoperative radiation therapy. METHODS AND MATERIALS The incidence of and mortality from acute myocardial infarction was assessed in a group of 684 women with early-stage breast cancer diagnosed during 1976-1987 who had been treated with breast conserving surgery plus postoperative radiation therapy given with tangential photon fields. In 94% of the patients the total dose was between 48-52 Gy given with 2 Gy daily fractions 5 days per week for a total treatment period of about 4 1/2-5 1/2 weeks. In 88% of the patients the target volume included the breast parenchyma alone. In the remaining patients regional nodal areas were also irradiated. A concurrent group of 4,996 breast cancer patients treated with mastectomy without postoperative radiation therapy was used as a reference. RESULTS After a median follow-up of 9 years (range: 5-16 years) 12 conservatively treated patients (1.8%) had developed an acute myocardial infarction and 5 (0.7%) had died due to this disease. The age-adjusted relative hazard of acute myocardial infarction for the conservative group vs. the mastectomy group was 0.6 (95% C.I.: 0.4-1.2) and for death due to this disease 0.4 (0.2-1.1). The incidence of acute myocardial infarction among the conservatively treated women was similar irrespective of tumor laterality. CONCLUSIONS There was no indication of an increased risk of acute myocardial infarction with the radiation therapy among the women treated with conservative surgery. However, due to the small number of events the study could not exclude the possibility that cardiac problems may arise in some patients with left-sided cancers who have their heart located anteriorly in the mediastinum. Individual, three-dimensional dose planning represents one method to identify such patients and is basic to technical changes aimed at decreasing the cardiac radiation dose volume.

Attack rate, mortality and case fatality for acute myocardial infarction in Sweden during 1987-95. Results from the national AMI register in Sweden.

Abstract. Rosén M, Alfredsson L, Hammar N, Kahan T, Spetz C‐L, Ysberg A‐S (Centre for Epidemiology, National Board of Health and Welfare, Stockholm; University of Umeå, Umeå; Karolinska Institutet, Stockholm; Karolinska Hospital, Stockholm; and Karolinska Institutet, Danderyd Hospital, Danderyd, Sweden). Attack rate, mortality and case fatality for acute myocardial infarction in Sweden 1987–95. Results from the National AMI Register in Sweden. J Intern Med 2000; 248: 159–164.

Comparison of Early and Late Mortality in Men and Women After Isolated Coronary Artery Bypass Graft Surgery in Stockholm, Sweden, 1980 to 1989

OBJECTIVES We sought to analyze early and late mortality after coronary artery bypass graft surgery (CABG) in relation to gender. BACKGROUND Early mortality after CABG is generally higher in women than in men, but the causes are controversial. Few studies have investigated long-term mortality after CABG in relation to gender. METHODS In all, 3,326 men and 607 women underwent isolated CABG in Stockholm from 1980 to 1989. Mortality for these patients was followed by means of the National Cause of Death Register, from the time of operation until the end of 1990. Survival was evaluated by life-table methods and by proportional hazards regression. RESULTS Early mortality (within 30 days) was 3% in women and 1.7% in men, corresponding to a relative risk of 1.8 (95% confidence interval [CI] 1.0 to 3.0) in women compared with men. When age and body surface area were taken into account, the relative risk was 1.0 (95% CI 0.5 to 2.0), which was not markedly different but multivariate analyses that included hypertension, diabetes mellitus, previous myocardial infarction, left ventricular function and number of diseased vessels. Only small gender differences in mortality were observed for 5 years after the operation among those who survived for 30 days. CONCLUSIONS The results suggest that men and women run similar risks of early and late mortality after CABG when patient characteristics are taken into account.