Table 1.

Descriptive characteristics of colorectal cancer cases and controls in a nested case-control study within the ATBC Study.

Variable	Controls	Colorectal cancer	P value1	Colon cancer	P value1	Rectal cancer	P value1
Total N	523	523		284		239
Age at randomization, years, Mean (SD)	57 (5)	57 (5)	0.98	57 (5)	0.73	57 (5)	0.72
Education: post-elementary school, N (%)	84 (16)	93 (18)	0.46	50 (18)	0.57	43 (18)	0.51
Years of smoking, Mean (SD)	35 (9)	35 (8)	0.20	36 (8)	0.09	35 (8)	0.76
Cigarettes/day, Mean (SD)	19 (9)	20 (9)	0.68	20 (9)	0.72	20 (9)	0.75
Physically active, N (%)2	113 (22)	116 (22)	0.81	58 (20)	0.71	58 (24)	0.41
BMI (Kg/m2), Mean (SD)	26 (4)	27 (4)	0.28	27 (4)	0.08	26 (4)	0.89
Self-reported history of diabetes, N (%)	17 (3)	14 (3)	0.58	13 (5)	0.34	1 (0.5)	0.02
Blood glucose ≥ 126 mg/dL, N (%)	1 (0.2)	13 (3)	0.001	6 (2)	0.005	7 (3)	0.001
Ever daily use of analgesics, N (%)3	66 (15)	51 (13)	0.33	25 (12)	0.25	26 (14)	0.70
Alcohol, g/day, Mean (SD)	16 (20)	19 (21)	0.03	20 (22)	0.01	18 (19)	0.26
Red meat, g/day, Mean (SD)	71 (33)	74 (34)	0.15	74 (35)	0.28	74 (34)	0.18
Processed meat, g/day, Mean (SD)	81 (66)	77 (58)	0.31	74 (57)	0.14	81 (60)	0.93
Fruit, g/day, Mean (SD)	228 (218)	221 (193)	0.62	221 (194)	0.70	221(193)	0.68
Vegetables, g/day, Mean (SD)	310 (123)	303 (112)	0.39	298 (111)	0.19	310 (113)	0.99
Fiber, g/day, Mean (SD)	19 (10)	18 (10)	0.09	18 (10)	0.07	19 (10)	0.35
Total energy (kcal/day), Mean (SD)	2729 (746)	2691 (711)	0.41	2677 (717)	0.35	2708 (706)	0.71
Serum ghrelin (pg/ml), Mean (SD)	794 (351)	761 (385)	0.15	753 (360)	0.11	771 (414)	0.43

¹P values from Student’s t test and Pearson’s χ² test, as appropriate, comparing cases to controls.

²Physically active: Light or moderate physical activity in leisure time.

³Have you ever used any prescribed or over-the-counter analgesic drugs daily for at least a month?