Torstein Hole

Age-specific prevalence of the metabolic syndrome defined by the International Diabetes Federation and the National Cholesterol Education Program: the Norwegian HUNT 2 study

BackgroundThe 2005 International Diabetes Federation (IDF) definition of the metabolic syndrome was designed to be useful worldwide, but to date few prevalence studies have used that definition in European populations. We estimated the age- and sex-stratified prevalence of IDF-defined metabolic syndrome in a county of Norway and compared it with the prevalence estimated using the revised National Cholesterol Education Program-Adult Treatment Panel-III definition (2005 ATP III).MethodsCross-sectional analysis of 10,206 participants aged 20–89 years in the Nord-Trøndelag Health Study 1995–97 (HUNT 2).ResultsPrevalence of IDF-defined metabolic syndrome was 29.6% (95% CI: 28.8 to 30.5), compared to 25.9% (95% CI: 25.0 to 26.7) using the 2005 ATP III criteria. The prevalence of IDF-defined metabolic syndrome increased from 11.0% in the 20–29 years age group to 47.2% in the 80–89 years group in men, and from 9.2% to 64.4% for women in the corresponding age groups. Among men and women aged ≥60 years, the IDF criteria classified 56.7% and 75.0%, respectively, as having central obesity, and 89.3% and 90.9%, respectively, as being hypertensive.ConclusionAccording to both definitions, the prevalence of the metabolic syndrome increased strongly with age. The IDF and the American Heart Association/National Heart, Lung, and Blood Institute guidelines for clinical management of metabolic syndrome would classify a high proportion of elderly Norwegians as in need of overall risk assessment for cardiovascular disease.

Cardiovascular risk of high-versus moderate-intensity aerobic exercise in coronary heart disease patients

Background— Exercise performed at higher relative intensities has been found to elicit a greater increase in aerobic capacity and greater cardioprotective effects than exercise at moderate intensities. An inverse association has also been detected between the relative intensity of physical activity and the risk of developing coronary heart disease, independent of the total volume of physical activity. Despite that higher levels of physical activity are effective in reducing cardiovascular events, it is also advocated that vigorous exercise could acutely and transiently increase the risk of sudden cardiac death and myocardial infarction in susceptible persons. This issue may affect cardiac rehabilitation. Methods and Results— We examined the risk of cardiovascular events during organized high-intensity interval exercise training and moderate-intensity training among 4846 patients with coronary heart disease in 3 Norwegian cardiac rehabilitation centers. In a total of 175 820 exercise training hours during which all patients performed both types of training, we found 1 fatal cardiac arrest during moderate-intensity exercise (129 456 exercise hours) and 2 nonfatal cardiac arrests during high-intensity interval exercise (46 364 exercise hours). There were no myocardial infarctions in the data material. Because the number of high-intensity training hours was 36% of the number of moderate-intensity hours, the rates of complications to the number of patient-exercise hours were 1 per 129 456 hours of moderate-intensity exercise and 1 per 23 182 hours of high-intensity exercise. Conclusions— The results of the current study indicate that the risk of a cardiovascular event is low after both high-intensity exercise and moderate-intensity exercise in a cardiovascular rehabilitation setting. Considering the significant cardiovascular adaptations associated with high-intensity exercise, such exercise should be considered among patients with coronary heart disease.

Aerobic interval training increases peak oxygen uptake more than usual care exercise training in myocardial infarction patients: a randomized controlled study

Objective: Exercise capacity strongly predicts survival and aerobic interval training (AIT) increases peak oxygen uptake effectively in cardiac patients. Usual care in Norway provides exercise training at the hospitals following myocardial infarction (MI), but the effect and actual intensity of these rehabilitation programmes are unknown. Design: Randomized controlled trial. Setting: Hospital cardiac rehabilitation. Subjects: One hundred and seven patients, recruited two to 12 weeks after MI, were randomized to usual care rehabilitation or treadmill AIT. Interventions: Usual care aerobic group exercise training or treadmill AIT as 4 × 4 minutes intervals at 85–95% of peak heart rate. Twice weekly exercise training for 12 weeks. Main measures: The primary outcome measure was peak oxygen uptake. Secondary outcome measures were endothelial function, blood markers of cardiovascular disease, quality of life, resting heart rate, and heart rate recovery. Results: Eighty-nine patients (74 men, 15 women, 57.4 ± 9.5 years) completed the programme. Peak oxygen uptake increased more (P = 0.002) after AIT (from 31.6 ± 5.8 to 36.2 ± 8.6 mL·kg−1·min−1, P < 0.001) than after usual care rehabilitation (from 32.2 ± 6.7 to 34.7 ± 7.9 mL·kg−1·min−1, P < 0.001). The AIT group exercised with significantly higher intensity in the intervals compared to the highest intensity in the usual care group (87.3 ± 3.9% versus 78.7 ± 7.2% of peak heart rate, respectively, P < 0.001). Both programmes increased endothelial function, serum adiponectin, and quality of life, and reduced serum ferritin and resting heart rate. High-density lipoprotein cholesterol increased only after AIT. Conclusions: AIT increased peak oxygen uptake more than the usual care rehabilitation provided to MI patients by Norwegian hospitals.

Prehospital delay, contributing aspects and responses to symptoms among Norwegian women and men with first time acute myocardial infarction.

Background: In patients with acute myocardial infarction (AMI), the delay between the onset of symptoms and hospital admission is a critical factor in reducing morbidity and mortality. Aims: To assess gender differences in prehospital delay among women and men with first time AMI, generate more knowledge about aspects influencing this delay and investigate responses to acute symptoms. Methods and result: Of 738 eligible patients, 149 women and 384 men responded to a questionnaire (72%). Over half of both women and men waited over one hour before they called for medical assistance and more than half the patients had a total prehospital delay exceeding two hours. Rapid development of symptoms and symptoms matching expectations reduced, self medication and consulting the spouse increased patient delay in both genders. Calling the Emergency Medical Service (EMS) reduced and calling a general practitioner increased total prehospital delay in both genders. ST-elevation: (STEMI), symptoms experienced as unbearable and attributed as cardiac reduced patient delay, and symptoms from the back, shoulders or between scapulae increased prehospital delay, only in men. Conclusion: How patients responded to symptoms had vital impact on prehospital delay among both genders, but the experience and interpretation of symptoms had more influence in men than in women.

High-Intensity Interval Training in Patients with Heart Failure with Reduced Ejection Fraction

Background: Small studies have suggested that high-intensity interval training (HIIT) is superior to moderate continuous training (MCT) in reversing cardiac remodeling and increasing aerobic capacity in patients with heart failure with reduced ejection fraction. The present multicenter trial compared 12 weeks of supervised interventions of HIIT, MCT, or a recommendation of regular exercise (RRE). Methods: Two hundred sixty-one patients with left ventricular ejection fraction ⩽35% and New York Heart Association class II to III were randomly assigned to HIIT at 90% to 95% of maximal heart rate, MCT at 60% to 70% of maximal heart rate, or RRE. Thereafter, patients were encouraged to continue exercising on their own. Clinical assessments were performed at baseline, after the intervention, and at follow-up after 52 weeks. Primary end point was a between-group comparison of change in left ventricular end-diastolic diameter from baseline to 12 weeks. Results: Groups did not differ in age (median, 60 years), sex (19% women), ischemic pathogenesis (59%), or medication. Change in left ventricular end-diastolic diameter from baseline to 12 weeks was not different between HIIT and MCT (P=0.45); left ventricular end-diastolic diameter changes compared with RRE were −2.8 mm (−5.2 to −0.4 mm; P=0.02) in HIIT and −1.2 mm (−3.6 to 1.2 mm; P=0.34) in MCT. There was also no difference between HIIT and MCT in peak oxygen uptake (P=0.70), but both were superior to RRE. However, none of these changes was maintained at follow-up after 52 weeks. Serious adverse events were not statistically different during supervised intervention or at follow-up at 52 weeks (HIIT, 39%; MCT, 25%; RRE, 34%; P=0.16). Training records showed that 51% of patients exercised below prescribed target during supervised HIIT and 80% above target in MCT. Conclusions: HIIT was not superior to MCT in changing left ventricular remodeling or aerobic capacity, and its feasibility remains unresolved in patients with heart failure. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00917046.

High Intensity Interval Training in Heart Failure Patients with Reduced Ejection Fraction

Background: Small studies have suggested that high-intensity interval training (HIIT) is superior to moderate continuous training (MCT) in reversing cardiac remodeling and increasing aerobic capacity in patients with heart failure with reduced ejection fraction. The present multicenter trial compared 12 weeks of supervised interventions of HIIT, MCT, or a recommendation of regular exercise (RRE). Methods: Two hundred sixty-one patients with left ventricular ejection fraction ⩽35% and New York Heart Association class II to III were randomly assigned to HIIT at 90% to 95% of maximal heart rate, MCT at 60% to 70% of maximal heart rate, or RRE. Thereafter, patients were encouraged to continue exercising on their own. Clinical assessments were performed at baseline, after the intervention, and at follow-up after 52 weeks. Primary end point was a between-group comparison of change in left ventricular end-diastolic diameter from baseline to 12 weeks. Results: Groups did not differ in age (median, 60 years), sex (19% women), ischemic pathogenesis (59%), or medication. Change in left ventricular end-diastolic diameter from baseline to 12 weeks was not different between HIIT and MCT (P=0.45); left ventricular end-diastolic diameter changes compared with RRE were −2.8 mm (−5.2 to −0.4 mm; P=0.02) in HIIT and −1.2 mm (−3.6 to 1.2 mm; P=0.34) in MCT. There was also no difference between HIIT and MCT in peak oxygen uptake (P=0.70), but both were superior to RRE. However, none of these changes was maintained at follow-up after 52 weeks. Serious adverse events were not statistically different during supervised intervention or at follow-up at 52 weeks (HIIT, 39%; MCT, 25%; RRE, 34%; P=0.16). Training records showed that 51% of patients exercised below prescribed target during supervised HIIT and 80% above target in MCT. Conclusions: HIIT was not superior to MCT in changing left ventricular remodeling or aerobic capacity, and its feasibility remains unresolved in patients with heart failure. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00917046.

Hyperferritinemia is associated with insulin resistance and fatty liver in patients without iron overload.

Objective During the last 10 years we have experienced an increasing number of referrals due to hyperferritinemia. This is probably due to increased awareness of hereditary hemochromatosis, and the availability of a genetic test for this condition. Most of these referred patients were over-weight middle-aged men with elevated ferritin levels, but without the hemochromatosis-predisposing gene mutations. We evaluated the relationship between hyperferritinemia and the metabolic syndrome in 40 patients. Methods Forty consecutive patients referred for hyperferritinemia were investigated. The examination programme included medical history, clinical investigation and venous blood samples drawn after an overnight fast. This resulted in 34 patients with unexplained hyperferritinemia, which were further examined. Liver biopsy was successfully performed in 29 subjects. Liver iron stores were assessed morphologically, and by quantitative phlebotomy in 16 patients. Results The majority of the patients had markers of the metabolic syndrome, and 18 patients (52%) fulfilled the IDF-criteria for the metabolic syndrome. Mean body mass index was elevated (28,8±4,2), mean diastolic blood pressure was 88,5±10,5 mmHg, and mean fasting insulin C-peptide 1498±539 pmol/l. Liver histology showed steatosis and nuclear glycogen inclusions in most patients (19 out of 29). Only four patients had increased iron stores by histology, of which two could be explained by alcohol consumption. Fourteen of 16 patients normalized ferritin levels after phlebotomy of a cumulative blood amount corresponding to normal iron stores. Ferritin levels were significantly related to insulin C-peptide level (p<0.002) and age (p<0.002). Conclusion The present results suggest that liver steatosis and insulin resistance but not increased iron load is frequently seen in patients referred for suspected hemochromatosis on the basis of hyperferritinemia. The ferritin level seems to be positively associated to insulin resistance.

Long-term follow-up after cardiac rehabilitation: A randomized study of usual care exercise training versus aerobic interval training after myocardial infarction☆

due to discontinuedtraining.The design and methods of this randomized controlled trial havebeen prescribed in detail earlier [5]. Briefly, patients with an MI2–12 weeks ago were included and did either AIT as 4 times 4 minof treadmill walking at about 90% of individual heart rate maximum,or usual care continuous aerobic exercise for 60 min, twice weekly for12 weeks. The intensity during usual care was set to be moderate-to-high, and controlled by subjective ratings of perceived exertion.Datawascollectedat4timepoints;beforeandaftertraining,andat6and 30 months follow-up (Fig. 1). The primary outcome measure wasVO

Letter to the EditorLong-term follow-up after cardiac rehabilitation: A randomized study of usual care exercise training versus aerobic interval training after myocardial infarction☆

due to discontinuedtraining.The design and methods of this randomized controlled trial havebeen prescribed in detail earlier [5]. Briefly, patients with an MI2–12 weeks ago were included and did either AIT as 4 times 4 minof treadmill walking at about 90% of individual heart rate maximum,or usual care continuous aerobic exercise for 60 min, twice weekly for12 weeks. The intensity during usual care was set to be moderate-to-high, and controlled by subjective ratings of perceived exertion.Datawascollectedat4timepoints;beforeandaftertraining,andat6and 30 months follow-up (Fig. 1). The primary outcome measure wasVO

Renal Function in Outpatients With Chronic Heart Failure

BACKGROUND Impaired renal function confers an adverse prognosis in patients with heart failure (HF). The aims of the present study were to identify factors associated with and predictive of impaired renal function and to assess the relationship between estimated glomerular filtration rate (eGFR) and all-cause mortality in outpatients with HF. METHODS AND RESULTS Baseline data on 3605 patients (median age 73 years, 70.1% men) from 24 outpatient HF clinics in Norway were analyzed. Median follow-up time was 9 months. Renal dysfunction (eGFR < 60 mL/min) was present in 44.9%. The population was randomized into equal-sized model-building and validation samples to enhance model stability. eGFR was an independent predictor of all-cause mortality (HR 0.94 per 5 mL/min increase, P = .001). Use of spironolactone (P = .002), higher blood pressure (P < .001), and lower hemoglobin levels (P = .002) were predictors of impaired renal function. Increasing doses of loop diuretics were strongly associated with eGFR at baseline (P < .001), but only tended to predict worsening renal function during follow-up (P = .08). CONCLUSIONS Clinically significant reduction in renal function was prevalent in outpatients with HF, and was a strong predictor of all-cause mortality. Use of loop diuretics and spironolactone should be carefully evaluated as these agents may adversely affect renal function.