TABLE 2.

Hazard ratios and 95% confidence intervals of lung cancer according to physical activity levels and inflammatory markers.

	No. of cases	Person years*	HR (95% CI)†	Ptrend†	HR (95% CI)‡	Ptrend‡
Episodes of sweat-inducing activities per week
0	105	36753	1		1
1–3	10	10862	0.44 (0.23–0.85)		0.45 (0.23–0.87)
≥4	19	9611	0.75 (0.45–1.24)	0.08	0.76 (0.46–1.26)	0.09
City blocks walked per day
0	73	25117	1		1
1–11	44	19633	0.93 (0.63–1.37)		0.92 (0.62–1.35)
≥12	17	12292	0.53 (0.31–0.90)	0.03	0.52 (0.30–0.89)	0.02
Flights of stairs climbed per day
0–1	44	17715	1		1
2–5	60	20224	1.53 (1.02–2.29)		1.53 (1.02–2.29)
>5	30	19254	0.84 (0.52–1.36)	0.58	0.86 (0.53–1.40)	0.67
Total physical activity index (kcal/week)§
0–174	65	18531	1		1
175–874	38	19120	0.72 (0.47–1.09)		0.72 (0.48–1.09)
≥875	31	19358	0.55 (0.35–0.86)	0.01	0.56 (0.35–0.87)	0.01
Heart rate (30 sec.)
21–33	27	12065	1		1
34–42	70	33925	0.93 (0.59–1.46)		0.95 (0.60–1.49)
>42	37	11235	1.30 (0.80–2.16)	0.27	1.25 (0.75–2.09)	0.35
WBC tertile (×103/μL)
<6.4	16	19605	1		--
6.4–7.9	50	19421	2.74 (1.53–4.90)		--
≥8	68	18019	2.81 (1.58–5.01)	0.001	--
Albumin tertile (g/dL)
<4.6	52	19307	1		--
4.6–4.8	51	20321	1.02 (0.69–1.52)		--
≥4.9	31	17427	0.85 (0.54–1.34)	0.52	--

WBC = white blood cell count; HR = hazard ratio.

^*Total person years for cases and noncases in category of activity.

^†Models are adjusted for age, sex, pack-years of smoking, time since smoking cessation, body mass index, alcohol intake, and education.

^‡Models are adjusted for all variables in †, plus white blood cell count.

^§Kilocalories per week from city blocks walked, flights of stairs climbed, and sweat-inducing activities (see Methods).