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Objective To examine whether elevated resting heart rate (RHR) is an independent risk factor for mortality or a mere marker of physical fitness (VO2Max). Methods This was a prospective cohort study: the Copenhagen Male Study, a longitudinal study of healthy middle-aged employed men. Subjects with sinus rhythm and without known cardiovascular disease or diabetes were included. RHR was assessed from a resting ECG at study visit in 1985-1986. VO2Max was determined by the Åstrand bicycle ergometer test in 1970-1971. Subjects were classified into categories according to level of RHR. Associations with mortality were studied in multivariate Cox models adjusted for physical fitness, leisure-time physical activity and conventional cardiovascular risk factors. Results 2798 subjects were followed for 16 years. 1082 deaths occurred. RHR was inversely related to physical fitness (p<0.001). Overall, increasing RHR was highly associated with mortality in a graded manner after adjusting for physical fitness, leisure-time physical activity and other cardiovascular risk factors. Compared to men with RHR =50, those with RHR >90 had an HR (95% CI) of 3.06 (1.97 to 4.75). With RHR as a continuous variable, risk of mortality increased with 16% (10-22) per 10 beats per minute (bpm). There was a borderline interaction with smoking ( p=0.07); risk per 10 bpm increase in RHR was 20% (12-27) in smokers, and 14% (4-24) in non-smokers. Conclusions Elevated RHR is a risk factor for mortality independent of physical fitness, leisure-time physical activity and other major cardiovascular risk factors. [ABSTRACT FROM AUTHOR]

Background: The role of physical fitness (VO2Max (mlO2*min-1*kg-1)) as a risk factor for herniated lumbar disc disease (HLDD) is unknown. The objective of this study was to examine the association between aerobic (physical) fitness and risk of hospitalisation due to HLDD in a long-term follow up. Methods: The Copenhagen Male Study is a prospective cohort study established in 1970-71. At baseline, 5,249 men answered a questionnaire about their history of back disease, physical and psychosocial working conditions, lifestyle and social class. Height and weight was measured and aerobic capacity (physical fitness) was estimated based on a submaximal bicycle test. Information about hospitalization due to HLDD was obtained from the National Hospital Register covering the period 1977 - 2003. Hazard Ratios (HR) were calculated by Cox's proportional hazard regression model. Results: Among 3,833 men without history of low back disorders, 64 were hospitalized due to HLDD. The cumulative incidence of HLDD was 1.7% (n=34) among men with low physical fitness (15-32 ml O2*min-1*kg-1), and 1.7% (n=30) among men with high physical fitness (33-78 ml O2*min-1*kg-1). In a final model, adjusted for relevant confounders, the HR (95% CI) for HLDD for those with high physical fitness was 0.88 (0.51-1.50) compared to those with low physical fitness. In the same model, HR for men often exposed to strenuous work compared to those seldom or never exposed to strenuous work was 3.91(1.82-8.38). Also body height was a significant predictor. Conclusions: Physical fitness is not associated with hospitalisation due to HLDD, and the only modifiable risk factor for hospitalisation due to HLDD seems to be strenuousness at work. [ABSTRACT FROM AUTHOR]

Objective. The role of salt intake as a risk factor for asthma, bronchial hyperresponsiveness, and other bronchial symptoms has been addressed in a number of studies. Collectively, these studies indicate an increased risk of bronchial symptoms with high consumption of salt, but the issue remains controversial. We tested prospectively the hypothesis that salt intake would be an independent risk factor for chronic bronchitis (CB). Design. A 10-year prospective study of 2,183 men aged 46 to 65 years without any relevant lung symptoms at baseline. Main Outcome. Chronic bronchitis. Results. During the 10-year followup, the overall incidence of CB was 7.1% among men without any relevant lung symptoms at baseline. In a multiple logistic regression analysis, controlling for age, smoking habits, occupational dust exposure, alcohol use, and social class, the odds ratio associated with self-assessed high salt preference (reported by 24%) was 1.6 (1.1--2.4). Interpretation. The results suggest that salt restriction may prevent chronic bronchitis. [ABSTRACT FROM AUTHOR]

Objective Increased risk of ischemic heart disease (IHD) mortality from high physical work demands has been observed among men with low physical fitness and leisure time physical activity. We tested whether hypertensive men are at a particularly high risk of IHD mortality when exposed to high physical work demands. Method We carried out a 30-year follow-up of the Copenhagen Male Study of 5249 gainfully employed men aged 40-59 years. Of these, 274 men with a history of myocardial infarction or prevalent symptoms of angina pectoris or intermittent claudication were excluded from the follow-up. Men were classified as having hypertension when any of the following factors was present: (i) treatment for hypertension, (ii) a systolic blood pressure of >160 mm Hg, or (iii) a diastolic blood pressure of >90 mm Fig. Physical work demands were determined by two self-reported questions. Results Of the eligible study population, 587 men (11.9%) died due to THD. Hypertensive men had more than a doubled risk of IHD mortality [hazard ratio (HR) 2.16, 95% confidence interval (95% CI) 1.80-2.59]. Cox analyses - adjusted for age, smoking, alcohol, body mass index, diabetes, physical fitness, leisure time physical activity, and social class - showed that high physical work demands were associated with an increased risk of IHD and all-cause mortality among normotensive men (N=4 127, HR 1.36,95% CI 0.96-1.92 and HR 1.24, 95% CI 1.06-1.44, respectively), but not among the hypertensive men (N=808, HR 1.07, 95% CI 0.63-1.81 and HR 1.07, 95% CI 0.80-1.42, respectively) using men with low physical work demands as the reference. Conclusion Compared to normotensive men, hypertensive men did not have a higher risk of IHD or all-cause mortality from high physical work demands. [ABSTRACT FROM AUTHOR]

Analyzes the nicotine concentration of house dust from the dwellings of smokers and nonsmokers in Copenhagen, Denmark. Use of gas chromotographic method; Correlation between the amount smoked and the nicotine concentration in the house dust; Use of nicotine as marker of tobacco pollution.