Five-year follow-up of ECG aberrations, latent coronary heart disease and cardiopulmonary fitness in various age groups of Norwegian cross-country skiers

Pre-participation and follow-up screening of athletes for endurance sport

Physical activity increases life expectancy and sport is a priori not harmful. Exhausted sporting activity (e.g. endurance running, triathlon, cycling or competitive sport) can lead under individual conditions to negative cardiac remodelling (pathological enlargement/function of cardiac cavities/structures) or in worst case to cardiac arrhythmias and sudden cardiac death (SCD). This individually disposition can be genetically determined or behaviourally/environmentally acquired. Overall competitive young male athletes suffer five-fold higher than non-competitive athletes from sudden death and athletes aged over 30 bear a potential for arrhythmias, atrial fibrillation or a 20-fold higher possibility for SCD as female athletes. Patients with diabetes, coronary disease, obesity or hypertension require different special managements. Screening of cardiorespiratory health for sport activities has a lot of faces. Basically there is a need for indicated examinations or possible preventive measures inside or outside of pre-competition screening. The costs of screening compared to expenditure of whole effort for sporting activities are acceptable or even negligible, but of course dependent on national/regional settings. The various causes and possibilities of screening will be discussed in this article as basic suggestion for an open discussion beyond national borders and settings.

Increased risk of atrial fibrillation among elderly Norwegian men with a history of long-term endurance sport practice

Atrial fibrillation (AF) is the most common cardiac arrhythmia. The prevalence increases with increasing age. In middle-aged men, endurance sport practice is associated with increased risk of AF but there are few studies among elderly people. The aim of this study was to investigate the role of long-term endurance sport practice as a risk factor for AF in elderly men. A cross-sectional study compared 509 men aged 65-90 years who participated in a long-distance cross-country ski race with 1768 men aged 65-87 years from the general population. Long-term endurance sport practice was the main exposure. Self-reported AF and covariates were assessed by questionnaires. Risk differences (RDs) for AF were estimated by using a linear regression model. After multivariable adjustment, a history of endurance sport practice gave an added risk for AF of 6.0 percent points (pp) (95% confidence interval 0.8-11.1). Light and moderate leisure-time physical activity during the last 12 months reduced the risk with 3.7 and 4.3 pp, respectively, but the RDs were not statistically significant. This study suggests that elderly men with a history of long-term endurance sport practice have an increased risk of AF compared with elderly men in the general population.

High prevalence of atrial fibrillation in long-term endurance cross-country skiers: echocardiographic findings and possible predictors--a 28-30 years follow-up study

BACKGROUND

Lone atrial fibrillation (LAF) seems to be more common in endurance-trained male athletes than in men in the general population. The reason for this has not been found.

AIM

To determine the prevalence of LAF in long-term endurance cross-country skiers and to examine possible predictors.

METHODS

Of 149 healthy, long-term trained cross-country skiers from three different age groups who were invited, 122 and 117 participated in the studies in 1976 and 1981, respectively. At follow-up in 2004-2006, 78 men participated, with 33 in age group I (54-62 years), 37 in group II (72-80 years) and eight in group III (87-92 years), whereas 37 individuals had died and seven could not be tracked. The examination programme applied in 1976, 1981 and 2004-2006 consisted of an electrocardiographic monitoring during rest and exercise and a maximal exercise test. Echocardiography was performed in 2004-2006.

RESULTS

A high prevalence (12.8%) of LAF was found. The only predictor from both 1976 and 1981 associated with LAF was a long PQ time (r=0.38, P=0.001 and r=0.27, P=0.02, respectively), whereas bradycardia was another predictor from 1981 (r=0.29, P=0.012). At follow-up, left atrial enlargement was a marker associated with LAF (P<0.001).

CONCLUSION

Long PQ time, bradycardia and left atrial enlargement seem to be important risk factors for LAF among long-term endurance cross-country skiers.

Assessment of physical activity by questionnaire and personal interview with particular reference to fitness and coronary mortality

Physical work capacity was measured by means of a symptom limited, near maximal cycle ergometer exercise test in two populations: a random sample of 95 military officers, and 2014 apparently healthy working males, 40-59 years old. Physical activity during leisure hours was assessed by means of a standardized questionnaire and by a personal interview with the officers and with 1769 of the other men. A 3 year total incidence of coronary heart disease (CHD) was recorded in the case of the officers and a 7 year CHD incidence and of CHD deaths was obtained for the 2014 working men. The data show that: A marked underestimation of the habitual levels of physical activity of the officers was obtained from the standardized questionnaire, as compared with that shown by the interview data. A far better agreement between the questionnaire and interview data on leisure time activity was observed among the mainly sedentary men. Physical work capacity was fairly well predicted from the questionnaire data in the sedentary men, but poorly predicted in the officers. CHD mortality in the sedentary men was highly correlated with working capacity in all age groups. Of 58 who died from CHD, 28 belonged to the lowest physical fitness quartile. This study indicates that questionnaires should be used with caution when assessing levels of habitual physical activity. It also suggests that a low physical work capacity is an important risk factor in CHD mortality.