Physical activity and primary cardiac arrest
D. S. Siscovick, N. S. Weiss, A. P. Hallstrom, T. S. Inui and D. R. Peterson
To explore the relationship between vigorous physical activity and primary
cardiac arrest (PCA), we identified, through emergency service incident
reports, 163 cases of PCA aged 25 to 75 years. Control subjects matched for
age, sex, residence, and the absence of prior clinical heart disease or
major comorbidity were identified from the community. Spouses of subjects
were interviewed to quantify leisure-time activity (LTA) during the prior
year. Energy expended in high-intensity LTA, requiring 60% of maximum
oxygen intake, was determined. The risk of PCA was 55% to 65% lower in
persons in the two upper quartiles of high-intensity LTA than in persons
without high-intensity LTA (95% confidence interval of relative risk, 0.22
to 0.85). Because this association was demonstrated in a clinically healthy
population without prior morbidity, our data support the hypothesis that
high-intensity LTA protects against PCA.
