Table 2.

Regression analysis of adverse events among Medicare outpatients who received initial CT colonography (CTC) or initial optical colonoscopy (OC) between January 2007 and December 2008^*

		Gastrointestinal Bleed		Perforation		Other Gastrointestinal events		Cardiovascular Events
		OR	95% CI	OR	95% CI	OR	95% CI	OR	95% CI
Total population (n = 155,316)
Type of Examination
	Initial CTC (n = 6,114)
	Initial OC (n = 149,202)	1.91	[1.47,2.49]	2.62	[0.84,8.22]	1.35	[1.07,1.69]	1.38	[1.18,1.62]
Age	66-74 (ref)
	75-84	1.38	[1.24,1.53]	1.18	[0.84,1.66]	1.39	[1.26,1.53]	1.44	[1.33,1.55]
	≥ 85	2.98	[2.61,3.41]	0.75	[0.38,1.46]	1.87	[1.63,2.15]	2.54	[2.29,2.80]

^*Regression analyses are adjusted for gender, age, race, comorbidities associated with adverse events (i.e. atrial fibrillation / flutter, congestive heart failure, chronic pulmonary disease, diabetes, stroke, renal disease, diverticulosis, obesity), and adverse events in preceding 90 days.