Table 4.

Mediation of Associations Between Waist Circumference^a and Risk of Colorectal Cancer by Inflammatory and Metabolic Biomarkers Using Alternative Waist Circumference Measures

	All Mediators		Inflammatory Mediatorsb		Metabolic Mediatorsc
	Average of 1987 and 1996 Waist Circumference Measures
	OR	95% CI	OR	95% CI	OR	95% CI
Total effect estimated	1.56	1.17, 2.08	1.56	1.17, 2.08	1.56	1.17, 2.08
Natural direct effect estimatee	1.55	1.08, 2.23	1.60	1.17, 2.19	1.50	1.05, 2.14
Natural indirect effect estimatef	1.01	0.75, 1.35	0.98	0.88, 1.10	1.04	0.75, 1.39
	1996 Waist Circumference Measure
	OR	95% CI	OR	95% CI	OR	95% CI
Total effect estimated	1.54	1.20, 1.98	1.54	1.20, 1.98	1.54	1.20, 1.98
Natural direct effect estimatee	1.34	0.98, 1.82	1.55	1.19, 2.03	1.34	0.99, 1.80
Natural indirect effect estimatef	1.15	0.86, 1.44	0.99	0.90, 1.09	1.15	0.87, 1.45

^aPer one-unit increase in the interquartile range of WC (average of 1987 and 1996 WC: 11.7 cm; 1996 WC: 13.3 cm)

^bIncludes C-reactive protein, interleukin-6, tumor necrosis factor receptor 2, and macrophage inhibitory cytokine-1

^cIncludes adiponectin, C-peptide, and soluble leptin receptor

^dAdjusted for age at blood draw (months), time of blood draw (month and year), energy intake (kcal/day, continuous), physical activity (MET-hrs/week, continuous), regular NSAID or aspirin use (< vs. ≥2 pills/week), family history of CRC (yes vs. no), red and processed meat intake (servings/day, continuous), total folate intake (mg/day), previous history of CRC screening (yes vs. no), smoking (packyears, continuous), regular multivitamin use (yes vs. no), supplemental calcium use (mg/day, continuous), alcohol intake (g/day, continuous), DASH score (continuous), and height (inches, continuous)

^eThe estimated effect of the exposure on colorectal cancer risk that is not mediated by the biomarkers of interest.

^fThe estimated effect of the exposure on colorectal cancer risk that is mediated by the biomarkers of interest.