Table 2.

Standardized risk, per 1000 individuals, of adverse events requiring an admission or an emergency room visit within 30 days of colonoscopy screening, Medicare 2004–2012.

	Ages 70–74				Ages 75–79
	Colonoscopy		No screening		Colonoscopy		No screening
	n	Risk (95% CI)	n	Risk (95% CI)	n	Risk (95% CI)	n	Risk (95% CI)
Any adverse event	691	15.4 (14.2–16.7)	17,161	9.7 (9.6–9.9)	691	23.2 (21.7–25.0)	20,982	12.9 (12.7–13.0)
Serious GI events	40	0.9 (0.6–1.2)	181	0.1 (0.1–0.1)	25	0.8 (0.5–1.2)	250	0.2 (0.1–0.2)
Perforations	20	0.4 (0.2–0.6)	51	0 (0–0)	11	0.4 (0.2–0.6)	71	0 (0–0.1)
GI bleeding requiring transfusion	20	0.4 (0.3–0.7)	130	0.1 (0.1–0.1)	14	0.5 (0.2–0.7)	180	0.1 (0.1–0.1)
Other GI events	257	5.6 (4.9–6.2)	4,331	2.5 (2.4–2.5)	206	6.9 (6.0–7.7)	5,003	3.2 (3.1–3.3)
GI bleeding not requiring transfusion	55	1.2 (0.9–1.6)	344	0.2 (0.2–0.2)	48	1.6 (1.2–2.2)	448	0.3 (0.3–0.3)
Paralytic ileus	41	0.9 (0.6–1.2)	266	0.2 (0.1–0.2)	41	1.3 (0.9–1.8)	290	0.2 (0.2–0.2)
Nausea and vomiting, dehydration	100	2.2 (1.8–2.6)	2,377	1.3 (1.3–1.4)	86	2.9 (2.3–3.5)	2,972	1.8 (1.8–1.9)
Abdominal pain	71	1.5 (1.2–1.9)	1,691	1.0 (0.9–1.0)	43	1.4 (1.0–1.8)	1,679	1.0 (1.0–1.1)
Cardiovascular events	473	10.7 (9.7–11.6)	14,026	8.4 (8.2–8.5)	538	18.1 (16.8–19.7)	17,638	10.8 (10.7–11.0)
MI or angina	66	1.5 (1.1–1.9)	2,957	1.7 (1.6–1.7)	82	2.7 (2.2–3.3)	3,274	2.0 (1.9–2.1)
Arrhythmias	297	6.8 (6.0–7.6)	7,752	4.4 (4.3–4.5)	351	12.0 (10.8–13.3)	10,471	6.4 (6.3–6.6)
Congestive heart failure	124	2.9 (2.4–3.4)	4,709	2.7 (2.6–2.7)	160	5.6 (4.8–6.4)	5,951	3.7 (3.6–3.8)
Cardiac or respiratory arrest	30	0.7 (0.4–0.9)	572	0.3 (0.3–0.3)	26	0.9 (0.5–1.2)	654	0.4 (0.4–0.5)
Syncope, hypotension/shock	117	2.6 (2.1–3.1)	3,026	1.7 (1.7–1.8)	118	3.9 (3.2–4.6)	3,828	2.4 (2.3–2.4)

GI: gastrointestinal, MI: myocardial infarction.