Table 1. Characteristic of Colon Cancer Patients and Control Subjects.

		Cancer Cases (N=6,462)		Control Subjects (N=11,483)
		N	(%)	N	(%)
Age	66-70 years	1251	19.36	2203	19.18
	71-75 years	1629	25.21	2920	25.43
	76-80 years	1542	23.86	2777	24.18
	>80 years	2040	31.57	3583	31.2
Race	White	5711	88.38	10123	88.16
	African American	751	11.62	1360	11.84
Sex	Male	2841	43.96	5039	43.88
	Female	3621	56.04	6444	56.12
SEER Stage	In situ	275	4.26	n.a.	n.a.
	Local	2412	37.33	n.a.	n.a.
	Regional	2631	40.71	n.a.	n.a.
	Distant	1144	17.7	n.a.	n.a.
Census tract median annual income	≤$25k	1853	28.68	3305	28.78
	$25k to ≤$35k	2053	31.77	3644	31.73
	$35k to ≤$45k	1449	22.42	2566	22.35
	>$45k	823	12.74	1454	12.66
	Missing	284	4.39	514	4.48
		N	(%)	N	(%)
Charlson Index	0*	4264	65.99	8048	70.09
	1*	1271	19.67	2080	18.11
	2	500	7.74	805	7.01
	3+*	427	6.61	550	4.79
	Myocardial infarction	105	1.62	154	1.34
	Congestive heart failure*	646	10	895	7.79
	Peripheral vascular disease	203	3.14	347	3.02
	Cerebrovascular disease	340	5.26	587	5.11
	Obstructive pulmonary disease*	701	10.85	1011	8.8
	Dementia*	74	1.15	229	1.99
	Diabetes*	1008	15.6	1373	11.96
	Chronic renal failure	74	1.15	144	1.25
	Ulcer*	129	2	127	1.11
	Rheumatism	96	1.49	172	1.5
	Alzheimer's disease*	123	1.9	363	3.16

^*Indicates cases and controls had statistically significantly (p<0.05) different comorbid conditions based on likelihood ratio tests in conditional logistic regressions. Conditions with prevalence less than 1% in both groups are not presented: paralysis, cirrhosis, and liver disease.

SOURCE: Michigan Tumor Resigtry, Medicare and Medicaid fee-for-service claims from 1996 to 2000.