. Author manuscript; available in PMC: 2020 Jun 1.

Published in final edited form as: Cancer Causes Control. 2019 Apr 8;30(6):637–649. doi: 10.1007/s10552-019-01165-3

Table 4.

HR and 95% CI of Dietary Calcium Intake and Colon Cancer Risk Overall and by Molecular Subtypes

		Dietary calcium intake (mg/day)
		0-599	600-749	750-899	≥900	Per 300	P_trend¹	P_{heterogeneity}²
Overall								NR
	Cases, n	590	537	360	356	1843
	Age-adjusted³	1 (ref)	0.95 (0.84, 1.07)	0.87 (0.76, 1.00)	0.72 (0.63, 0.82)	0.86 (0.81, 0.91)	<0.001
	Multivariable⁴	1 (ref)	0.99 (0.87, 1.11)	0.94 (0.82, 1.07)	0.79 (0.68, 0.91)	0.89 (0.84, 0.95)	0.001
CIMP status								0.01
	Negative/low
	Cases, n	198	173	134	99	604
	Age-adjusted³	1 (ref)	0.95 (0.77, 1.16)	1.01 (0.81, 1.26)	0.61 (0.48, 0.78)	0.81 (0.73, 0.90)	<0.001
	Multivariable⁴	1 (ref)	0.97 (0.79, 1.20)	1.07 (0.85, 1.35)	0.67 (0.52, 0.86)	0.84 (0.76, 0.94)	0.003
	High
	Cases, n	49	61	32	47	189
	Age-adjusted³	1 (ref)	1.32 (0.90, 1.92)	0.95 (0.61, 1.49)	1.23 (0.82, 1.85)	1.08 (0.90, 1.29)	0.43
	Multivariable⁴	1 (ref)	1.37 (0.94, 2.01)	1.01 (0.65, 1.59)	1.35 (0.90, 2.04)	1.12 (0.93, 1.34)	0.23
MSI status								0.02
	non-MSI-high
	Cases, n	200	199	130	112	641
	Age-adjusted³	1 (ref)	1.06 (0.87, 1.29)	0.94 (0.75, 1.17)	0.67 (0.53, 0.84)	0.82 (0.74, 0.91)	<0.001
	Multivariable⁴	1 (ref)	1.09 (0.89, 1.34)	1.01 (0.80, 1.27)	0.74 (0.58, 0.94)	0.86 (0.77, 0.95)	0.004
	High
	Cases, n	50	51	37	45	183
	Age-adjusted³	1 (ref)	1.05 (0.71, 1.56)	1.06 (0.69, 1.63)	1.12 (0.75, 1.68)	1.06 (0.88, 1.27)	0.54
	Multivariable⁴	1 (ref)	1.10 (0.74, 1.63)	1.13 (0.73, 1.74)	1.23 (0.82, 1.87)	1.10 (0.92, 1.32)	0.31
BRAF mutation								0.07
	(−)
	Cases, n	203	199	136	121	659
	Age-adjusted³	1 (ref)	1.03 (0.85, 1.26)	0.96 (0.77, 1.19)	0.70 (0.56, 0.88)	0.83 (0.75, 0.92)	<0.001
	Multivariable⁴	1 (ref)	1.07 (0.87, 1.30)	1.02 (0.82, 1.28)	0.77 (0.60, 0.97)	0.87 (0.78, 0.96)	0.01
	(+)
	Cases, n	50	52	31	38	171
	Age-adjusted³	1 (ref)	1.10 (0.75, 1.63)	0.93 (0.59, 1.46)	1.01 (0.66, 1.54)	1.02 (0.84, 1.23)	0.87
	Multivariable⁴	1 (ref)	1.15 (0.78, 1.70)	0.99 (0.63, 1.56)	1.11 (0.72, 1.71)	1.06 (0.87, 1.28)	0.57
KRAS mutation								0.84
	(−)
	Cases, n	171	153	113	104	541
	Age-adjusted³	1 (ref)	0.94 (0.76, 1.18)	0.96 (0.76, 1.22)	0.75 (0.58, 0.95)	0.87 (0.78, 0.97)	0.01
	Multivariable⁴	1 (ref)	0.98 (0.78, 1.22)	1.03 (0.80, 1.31)	0.82 (0.63, 1.06)	0.91 (0.81, 1.02)	0.10
	(+)
	Cases, n	84	97	55	56	292
	Age-adjusted³	1 (ref)	1.22 (0.91, 1.64)	0.93 (0.66, 1.31)	0.77 (0.55, 1.09)	0.86 (0.74, 0.99)	0.04
	Multivariable⁴	1 (ref)	1.25 (0.93, 1.68)	0.99 (0.70, 1.40)	0.84 (0.59, 1.19)	0.89 (0.77, 1.03)	0.13
PIK3CA mutation								0.42
	(−)
	Cases, n	202	195	134	116	647
	Age-adjusted³	1 (ref)	1.02 (0.84, 1.25)	0.95 (0.76, 1.18)	0.69 (0.55, 0.87)	0.86 (0.78, 0.95)	0.003
	Multivariable⁴	1 (ref)	1.06 (0.87, 1.30)	1.02 (0.81, 1.28)	0.77 (0.60, 0.98)	0.90 (0.81, 1.00)	0.05
	(+)
	Cases, n	30	42	22	34	128
	Age-adjusted³	1 (ref)	1.38 (0.86, 2.21)	1.02 (0.58, 1.77)	1.29 (0.78, 2.12)	0.95 (0.77, 1.19)	0.68
	Multivariable⁴	1 (ref)	1.43 (0.89. 2.29)	1.10 (0.63. 1.91)	1.41 (0.85. 2.34)	0.99 (0.80. 1.230	0.94

The P value for linear trend across calcium intake was from the Wald test on the continuous term of calcium intake.

The P value for heterogeneity across tumor markers was from the likelihood ratio test comparing the model in which a linear association with calcium intake was allowed to vary by tumor subtypes with the model in which a common association was assumed.

Age-adjusted analysis was adjusted for the same set of variables as denoted in Table 2.

⁴

Multivariable analysis was adjusted for supplemental calcium intake (<200, 200-299, 300-499, ≥500 mg/day) in addition to the same set of variables as denoted in Table 2.

Abbreviations: CIMP, CpG island methylator phenotype; MSI, microsatellite instability; NR, not relevant