. Author manuscript; available in PMC: 2014 Jun 1.

Published in final edited form as: Cancer Causes Control. 2013 Mar 26;24(6):1137–1146. doi: 10.1007/s10552-013-0192-2

Table 3.

Hazard Ratios (HR) of Colorectal Cancer Associated with Use of Glucosamine Plus Chondroitin, by Sex, Aspirin Use, Body Mass Index, Cancer Subsite, and Stage

	10-yr Use of Glucosamine Plus Chondroitin Supplements									P-trend	P-interaction^c/P-difference^d
	No Use			Low Use (<4 days/week or <3 yrs)			High Use (≥4 days/week and ≥3 yrs)
	Case/Cohort	HR^b	95% CI	Case/Cohort	HR^b	95% CI	Case/Cohort	HR^b	95% CI
Sex
Male	209/25,114	1.00	Ref	11/2,075	0.71	0.38, 1.32	5/1,234	0.51	0.21, 1.26	0.08	0.19
Female	136/21,618	1.00	Ref	27/3,306	1.41	0.91, 2.17	6/1,606	0.63	0.27, 1.46	0.94
Aspirin Use^e
Not regular	208/26,194	1.00	Ref	26/2,631	1.44	0.94, 2.22	6/1,288	0.57	0.25, 1.30	0.78	0.19
Regular	137/20,538	1.00	Ref	12/2,750	0.68	0.37, 1.25	5/1,552	0.50	0.20, 1.24	0.07
Body Mass Index
<25 kg/m²	96/15,831	1.00	Ref	14/1,840	1.49	0.83, 2.68	7/948	1.14	0.51, 2.52	0.40	0.006
≥25 kg/m²	249/30,901	1.00	Ref	24/3,541	0.92	0.60, 1.43	4/1,892	0.28	0.10, 0.76	0.02
Subsite^f
Colon	256/46,732	1.00	Ref	28/5,381	1.02	0.68, 1.53	9/2,840	0.57	0.29, 1.13	0.20	0.56
Rectum	89/46,732	1.00	Ref	10/5,381	1.24	0.63, 2.45	2/2,840	0.45	0.11, 1.85	0.54
Stage^g
Local	160/46,547	1.00	Ref	14/5,357	0.84	0.48, 1.48	4/2,833	0.42	0.15, 1.16	0.09	0.19
Regional/Distant	181/46,568	1.00	Ref	23/5,366	1.23	0.78, 1.93	7/2,836	0.66	0.31, 1.44	0.68

Abbreviations: HR (hazard ratio); 95% CI (95% confidence interval)

Users of glucosamine alone or chondroitin alone excluded from these analyses

Multivariate model adjusted for age, sex, race/ethnicity, education, BMI, energy intake, MET-hours per week of moderate/vigorous activity, alcohol intake, smoking history, multivitamin use, calcium intake (diet+supplement), dietary fiber intake, fruit and vegetable intake (excluding potatoes), red/processed meat intake, aspirin use, non-aspirin NSAID use, family history of colorectal cancer, history of sigmoidoscopy/colonoscopy, history of polyps, hormone replacement therapy, and history of arthritis or joint pain

P-interaction used to test for effect modification by sex, aspirin use, and body mass index

P-difference used to test for differences across cancer subsite and stage

Regular use of aspirin (including both low-dose and regular aspirin) defined as use at least once a week for a year over the 10 year period prior to baseline

Cancers of the subsite not under study included in subsite-stratified analyses and censored at date of diagnosis

Cancers of stages not under study excluded from stage-stratified analyses