Leisure-time, occupational, and commuting physical activity and risk of type 2 diabetes in Japanese workers: a cohort study

Table 2 Hazard ratios (95 % confidence intervals) of incident type 2 diabetes according to the dose of leisure-time moderate- and vigorous-intensity exercise

	Inactive	Low dose	Physical activity meeting recommendation		P for trend^a
			Medium dose	High dose
Medium exercise dose	0	3.7	10.5	23.0
No. of subjects	17,437	4,331	2,831	2,029
No. of cases	1,210	257	166	137
Person-years	91,266	23,080	13,278	12,116
Cases/ 10,000 person-years	133	111	125	113
Model 1^b	1.00 (reference)	0.83 (0.73, 0.95)	0.89 (0.76, 1.05)	0.78 (0.65, 0.93)	0.003
Model 2^c	1.00 (reference)	0.89 (0.78, 1.02)	0.95 (0.80, 1.11)	0.85 (0.71, 1.01)	0.06
Model 3^d	1.00 (reference)	0.87 (0.76, 1.00)	0.92 (0.78, 1.08)	0.83 (0.69, 0.99)	0.024

^aP for the trend was calculated using Cox proportional hazard regression, and ordinal numbers 0, 4, 11, and 23 were assigned to increasing levels of leisure-time physical activity, which was treated as continuous variable
^bAdjusted for age (years, continuous) and sex
^cAdjusted for age (years, continuous), sex, shift work (yes or no), sleep duration (<5, <6, 6 to <7, or ≥7 h per day), alcohol consumption (non-drinker, current drinker consuming <1, 1 to <2, or ≥2 go of Japanese sake equivalent per day [1 go of Japanese sake contains approximately 23 g of ethanol]), smoking (never, past, current smoker consuming 1 to 20 or ≥21 cigarettes per day), hypertension (yes or no), a family history of diabetes (yes or no), occupational activity (mostly sedentary, mostly standing, walking often, or fairly active), and walking for commuting to and from work (<20, 20 to <40, or ≥40 min of walking)
^dAdjusted for factors in model 2 plus body mass index (kg/m², continuous)

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