Table 4.

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 by indication^*

		Gastrointestinal Bleed		Perforation		Other Gastrointestinal events		Cardiovascular Events
		OR	95% CI	OR	95% CI	OR	95% CI	OR	95% CI
Asymptomatic population (n = 55,423)
Type of Examination
Initial CTC (n = 1,384)
Initial OC (n = 54,039)		2.29	[0.76, 6.90]	3.53	[0.20, 63.54]	2.36	[0.89, 6.30]	1.22	[0.74, 2.01]
Age	66-74 (ref)
	75-84	1.14	[0.87,1.48]	1.02	[0.49, 2.14]	0.92	[0.70, 1.22]	1.35	[1.10,1.64]
	≥ 85	1.49	[0.81, 2.75]	1.99	[0.45, 8.69]	1.22	[0.68, 2.20]	1.56	[1.05, 2.32]
Symptomatic population (n = 99,893)
Type of Examination
Initial CTC (n = 4,730)
Initial OC (n = 95,163)		1.92	[1.47, 2.51]	2.55	[0.73, 8.94]	1.35	[1.07,1.70]	1.43	[1.22, 1.68]
Age	66-74 (ref)
	75-84	1.36	[1.21,1.52]	1.20	[0.81,1.79]	1.40	[1.26, 1.56]	1.38	[1.27, 1.50]
	≥ 85	2.79	[2.43, 3.21]	0.67	[0.33, 1.37]	1.77	[1.53, 2.05]	2.37	[2.14, 2.63]

^*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.