Table 5. Joint analysis of TV watching and leisure-time physical activity on risk of adenoma, HPFS 1988–2008.

	Sitting while watching TV (h per week)
	0–6	7–13	14+	Pinteraction
Physical activitya (MET-h per week)
Total adenoma (n=4280)
Q5
No. of cases	279	288	195	0.98
OR (95% CI)	1.00 (ref.)	1.06 (0.90–1.26)	1.08 (0.89–1.30)
Q4
No. of cases	311	292	217
OR (95% CI)	1.10 (0.93–1.31)	1.08 z(0.91–1.28)	1.19 (0.99–1.43)
Q3
No. of cases	304	306	246
OR (95% CI)	1.07 (0.90–1.27)	1.10 (0.93–1.31)	1.33 (1.11–1.59)
Q2
No. of cases	308	339	241
OR (95% CI)	1.04 (0.88–1.23)	1.26 (1.07–1.49)	1.24 (1.03–1.49)
Q1
No. of cases	332	340	282
OR (95% CI)	1.10 (0.93–1.30)	1.27 (1.07–1.50)	1.25 (1.05–1.49)
High-risk adenoma (n=1833)
Q5
No. of cases	116	107	81	0.91
OR (95% CI)	1.00 (ref.)	0.91 (0.69–1.19)	0.98 (0.73–1.31)
Q4
No. of cases	128	115	98
OR (95% CI)	1.07 (0.83–1.38)	0.96 (0.74–1.25)	1.15 (0.87–1.51)
Q3
No. of cases	125	125	104
OR (95% CI)	1.02 (0.79–1.33)	1.02 (0.79–1.32)	1.20 (0.92–1.58)
Q2
No. of cases	122	147	102
OR (95% CI)	0.93 (0.72–1.21)	1.22 (0.95–1.57)	1.10 (0.83–1.45)
Q1
No. of cases	155	167	141
OR (95% CI)	1.10 (0.86–1.41)	1.34 (1.04–1.71)	1.29 (1.00–1.66)
Low-risk adenoma (n=1606)
Q5
No. of cases	123	121	71	0.30
OR (95% CI)	1.00 (ref.)	1.05 (0.81–1.35)	0.97 (0.72–1.30)
Q4
No. of cases	108	125	77
OR (95% CI)	0.89 (0.69–1.16)	1.09 (0.85–1.41)	1.06 (0.79–1.42)
Q3
No. of cases	122	115	88
OR (95% CI)	1.00 (0.78–1.30)	0.99 (0.77–1.29)	1.19 (0.90–1.58)
Q2
No. of cases	122	125	91
OR(95% CI)	0.98 (0.76–1.27)	1.12 (0.87–1.45)	1.19 (0.90–1.58)
Q1
No. of cases	117	109	92
OR (95% CI)	0.96 (0.74–1.25)	1.01 (0.77–1.32)	1.06 (0.80–1.40)

Abbreviations: BMI=body mass index; CI=confidence interval; HPFS=Health Professionals Follow-up Study; MET=metabolic equivalent of task; OR=odds ratio; ref.=referent.

^aQuintiles of physical activity were defined biennially among men who reported to have an endoscopy during the period. Median physical activity levels (MET-h per week) across quintiles were 67.6 (Q5), 39.7 (Q4), 25.9 (Q3), 15.9 (Q2) and 6.6 (Q1). The model was adjusted for age, time period of endoscopy, number of reported endoscopies, time since most recent endoscopy and reason for current endoscopy, family history of colorectal cancer, history of diabetes, height, alcohol intake, smoking, aspirin use, total calorie, folate, calcium intake, red and processed meat intake, and BMI.