TABLE 5.

PULMONARY FUNCTION, MUSCLE STRENGTH, AND LOSS OF THE ABILITY TO AMBULATE

Model	Pulmonary Function (HR [95% CI] P Value)	Respiratory Muscle Strength (HR [95% CI] P Value)	Leg Strength (HR [95% CI] P Value)
Model A	0.600 (0.454, 0.793)
	P < 0.001
Model B		0.513 (0.391, 0.672)
		P < 0.001
Model C			0.618 (0.464, 0.821)
			P < 0.001
Model D	0.724 (0.540, 0.971)	0.561 (0.422, 0.745)
	P = 0.031	P < 0.001
Model E	0.648 (0.490, 0.857)		0.656 (0.491, 0.877)
	P = 0.002		P = 0.004
Model F		0.567 (0.429, 0.749)	0.725 (0.542, 0.968)
		P < 0.001	P = 0.029
Model G	0.748 (0.558, 1.003)	0.612 (0.457, 0.820)	0.741 (0.552, 0.993)
	P = 0.053	P = 0.001	P = 0.045
Model H	0.827 (0.608, 1.125)	0.568 (0.417, 0.774)	0.761(0.564, 1.027)
	P = 0.227	P < 0.001	P = 0.074

The hazard ratios for the one unit difference in pulmonary function, respiratory muscle strength and leg strength are summarized for a series of discrete-time proportional hazards models for the time to becoming unable to ambulate and which were all adjusted for age, sex and education. Each model includes additional terms for various combinations of pulmonary function, respiratory muscle strength and leg strength as follows. Model A included a term for pulmonary alone; Model B included a term for respiratory muscle strength alone; Model C included a term for leg strength alone; Model D included terms for pulmonary function and respiratory muscle strength; Model E included terms for pulmonary function and leg strength; Model F included terms for respiratory muscle strength and leg strength; and Model G included terms for pulmonary function, respiratory muscle strength, and leg strength. Model H includes all the terms in Model G as well as terms for body mass index (BMI), BMI*BMI, physical activity, vascular risk factors, and vascular diseases.