Table 2.

Independent associations of cardiorespiratory fitness and grip strength with mortality from all causes, cardiovascular disease (CVD) and cancer

Mortality type	Comparisons	Number of deaths	Person-years of follow-up	Crude mortality rate per 100,000-person years	Hazard ratios (95% confidence interval)
					Model 1	Model 2	Model 3
All-cause mortality		832	379,682	219.1
	Categories of cardiorespiratory fitness
	Low (reference)	368	125,940	292.2	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Middle	253	126,043	200.7	0.74 (0.63, 0.87)	0.75 (0.64, 0.89)	0.76 (0.64, 0.89)
	High	211	127,700	165.2	0.65 (0.55, 0.78)	0.65 (0.56, 0.77)	0.65 (0.55, 0.78)
	P for linear trend				< 0.0001	< 0.0001	< 0.0001
	Per 1-SD increase in cardiorespiratory fitness				0.68 (0.60, 0.78)	0.77 (0.68, 0.87)	0.77 (0.69, 0.87)
	Categories of grip strength
	Low (reference)	349	136,899	254.9	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Middle	265	124,095	213.5	0.86 (0.73, 1.00)	0.88 (0.75, 1.04)	0.88 (0.75, 1.04)
	High	218	118,689	183.7	0.76 (0.64, 0.90)	0.80 (0.67, 0.96)	0.79 (0.66, 0.95)
	P for linear trend				0.001	0.014	0.010
	Per 1-SD increase in grip strength				0.91 (0.85, 0.98)	0.94 (0.87, 1.01)	0.93 (0.86, 1.01)
CVD mortality		177	379,682	46.6
	Categories of cardiorespiratory fitness
	Low (reference)	87	125,940	69.1	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Middle	55	126,043	43.6	0.70 (0.50, 0.98)	0.75 (0.53, 1.06)	0.75 (0.54, 1.06)
	High	35	127,700	27.4	0.56 (0.31, 0.68)	0.48 (0.32, 0.73)	0.49 (0.32, 0.74)
	P for linear trend				< 0.0001	< 0.0001	0.001
	Per 1-SD increase in cardiorespiratory fitness				0.45 (0.34, 0.59)	0.62 (0.48, 0.80)	0.62 (0.48, 0.80)
	Categories of grip strength
	Low (reference)	81	136,899	59.2	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Middle	54	124,095	43.5	0.75 (0.53, 1.06)	0.83 (0.58, 1.19)	0.83 (0.58, 1.18)
	High	42	118,689	35.4	0.61 (0.42, 0.89)	0.73 (0.49, 1.09)	0.71 (0.48, 1.06)
	P for linear trend				0.009	0.111	0.090
	Per 1-SD increase in grip strength				0.83 (0.71, 0.97)	0.90 (0.76, 1.06)	0.89 (0.76, 1.05)
Cancer mortality		503	379,682	132.5
	Categories of cardiorespiratory fitness
	Low (reference)	214	125,940	169.9	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Middle	152	126,043	120.6	0.77 (0.62, 0.95)	0.76 (0.62, 0.94)	0.76 (0.61, 0.94)
	High	137	127,700	107.3	0.74 (0.60, 0.93)	0.72 (0.58, 0.90)	0.72 (0.58, 0.90)
	P for linear trend				0.006	0.003	0.003
	Per 1-SD increase in cardiorespiratory fitness				0.75 (0.64, 0.89)	0.80 (0.68, 0.94)	0.80 (0.68, 0.94)
	Categories of grip strength
	Low (reference)	199	136,899	145.4	1.00 (reference)	1.00 (reference)	1.00 (reference)
	Middle	163	124,095	131.4	0.93 (0.75, 1.14)	0.94 (0.76, 1.16)	0.94 (0.76, 1.16)
	High	141	118,689	118.8	0.88 (0.71, 1.10)	0.91 (0.72, 1.14)	0.90 (0.72, 1.13)
	P for linear trend				0.259	0.393	0.352
	Per 1-SD increase in grip strength				1.00 (0.91, 1.10)	1.02 (0.92, 1.12)	1.01 (0.92, 1.12)

All models used age as the underlying time variable. Categories of aerobic fitness and grip strength were defined based on age and sex specific-categories of the baseline distribution. Aerobic fitness and grip strength were both normalized by fat-free mass

Model 1: No adjustment

Model 2: Adjusted for sex, waist circumference, ethnicity (White, mixed, Asian/Asian British, Black/Black British, other), smoking status (never, previous, current), employment (unemployed, employed), Townsend Deprivation Index, alcohol consumption (never, previous, currently < 3 times/week, currently ≥ 3 times/week), processed/red meat consumption (days/week), beta-blocker use, hypertension, and diabetes

Model 3: Model 2 plus grip strength in models where cardiorespiratory fitness was the exposure, or cardiorespiratory fitness in models where grip strength was the exposure

CVD cardiovascular disease, SD standard deviation