OBJECTIVE: To investigate sexual activity as a trigger of @entity583 and the potential effect modification of physical fitness. DESIGN: A case-crossover study nested in the Stockholm Heart Epidemiology Programme ( @entity742 ). SETTING: Stockholm County from April 1993 to December 1994. @entity1 : All @entity1 with a first episode of non-fatal @entity583 admitted to coronary care units were eligible, and 699 @entity1 participated in an interview. MAIN OUTCOME MEASURES: Relative risks with 95% confidence intervals. RESULTS: Only 1.3% of the @entity1 without premonitory symptoms had sexual activity during two hours before the onset of @entity583 . The relative risk of @entity583 was 2.1 (95% confidence interval (CI) 0.7 to 6.5) during one hour after sexual activity, and the risk among @entity1 with a sedentary life was 4.4 (95% CI 1.5 to 12.9). CONCLUSIONS: The increased risk of @entity583 after sexual activity and the further increase in risk among the less physically fit support the hypothesis of causal triggering by sexual activity. However, the absolute risk per hour is very low, and exposure is relatively infrequent. Thus having sex once a week only increases the annual risk of @entity583 slightly. Counselling should focus on encouraging @entity1 to live a physically active life and not on abstaining from sexual activity.

Sexual activity as a trigger of @entity583 . A case-crossover analysis in the Stockholm Heart Epidemiology Programme ( XXXX ).

@entity1 :: ('9606', 'Species') :: ['patients', 'PATIENTS'] @entity583 :: ('MESH:D009203', 'Disease') :: ['myocardial infarction', 'acute myocardial infarction'] @entity742 :: ('9940', 'Species') :: ['SHEEP']
@entity742 :: (9940,Species) :: ['SHEEP']
