Table 2.

Prevalence ratios and 95% confidence intervals of CAC based on walking metabolic activity in 2,971 participants from the NHLBI Family Heart Study

	Cases/n	*Crude	Age and sex adjusted	Full model
≤ 3.75 met-hrs/wk	206/829	1.0	1.0	1.0
>3.75–7.5 met-hrs/wk	82/423	0.73 (0.55–0.97)	0.70 (0.50–0.98)	0.53 (0.35–0.79)
>7.5–15 met-hrs/wk	176/873	0.76 (0.60–0.97)	0.81 (0.62–1.06)	0.72 (0.52–0.99)
>15–22.5 met-hrs/wk	83/450	0.68 (0.52–0.91)	0.72 (0.51–1.01)	0.54 (0.36–0.81)
>22.5 met-hrs/wk	79/392	0.76 (0.57–1.02)	0.92 (0.64–1.31)	0.76 (0.50–1.15)
p for trend		0.02	0.32	0.01

^*The crude model adjusted for familial clustering. The second model adjusted for age, sex and familial clustering. The full model adjusted for age, sex, race, smoking, alcohol use, total exercise metabolic activity index (excluding walking), and familial clustering.

CAC = coronary artery calcification, defined as CAC>100