Table 2.

Relative risk of atrial fibrillation according to frequency of habitual vigorous exercise

Variable: Frequency of Habitual Vigorous Exercise	Non-Exercisers	<1 day/wk	1−2 days/wk	3−4 days/wk	5−7 days/wk	P Value for Trend
Exercise at 3 Years
Age-Adjusted (Model 1)*
Relative risk	1.0	0.90	1.04	0.99	1.15
95% confidence interval		0.69−1.18	0.91−1.20	0.87−1.12	0.98−1.33	0.17
Multivariable Model 2†
Relative risk	1.0	0.87	1.05	1.00	1.13
95% confidence interval		0.66−1.15	0.91−1.22	0.87−1.14	0.97−1.33	0.19
Multivariable Model 3‡
Relative risk	1.0	0.90	1.09	1.04	1.20
95% confidence interval		0.68−1.20	0.95−1.26	0.91−1.19	1.02−1.41	0.040
Updated Exercise
Age-Adjusted (Model 1)*
Relative risk	1.0	1.09	1.02	0.96	1.08
95% confidence interval		0.83−1.43	0.88−1.18	0.85−1.09	0.93−1.26	0.69
Multivariable Model 2†
Relative risk	1.0	1.09	1.02	0.96	1.07
95% confidence interval		0.82−1.44	0.88−1.18	0.84−1.09	0.92−1.26	0.76
Multivariable Model 3‡
Relative risk	1.0	1.14	1.06	1.01	1.16
95% confidence interval		0.86−1.51	0.91−1.23	0.89−1.16	0.99−1.36	0.21

^*Model 1 controlled for age and treatment assignment (aspirin or placebo, beta carotene or placebo).

^†Model 2 excluded possible physiologic intermediaries between exercise and AF. Model 2 controlled for age, treatment assignment (aspirin or placebo, beta carotene or placebo), parental history of premature myocardial infarction, alcohol intake, smoking habits, fish consumption, multivitamin intake, vitamin C intake and vitamin E intake.

^‡Model 3 controlled for age, treatment assignment (aspirin or placebo, beta carotene or placebo), BMI, history of diabetes, history of hypertension, history of hyperlipidemia, parental history of premature myocardial infarction, alcohol intake, smoking habits, fish consumption, multivitamin intake, vitamin C intake, vitamin E intake, left ventricular hypertrophy, congestive heart failure, and evidence of cardiovascular disease.