Gastroenterol Res

Gastroenterology Research, ISSN 1918-2805 print, 1918-2813 online, Open Access

Article copyright, the authors; Journal compilation copyright, Gastroenterol Res and Elmer Press Inc

Journal website http://www.gastrores.org

Original Article

Volume 13, Number 1, February 2020, pages 19-24

The Impact of Hospital Teaching Status on Colonoscopy Perforation Risk: A National Inpatient Sample Study

**Table 1.** Demographic Characteristics of Patients Who Underwent Colonoscopy Between 2010 and 2014 Stratified by Teaching vs. Non-Teaching Facilities
Variables	Total	Non-teaching	Teaching	P value
SD: standard deviation.
No. of observations, unweighted	257,006	135,652	121,354
No. of observations, weighted	1,273,042	669,250	603,792
Age, mean (SD)		68 (15)	66 (15)	< 0.0001
Sex
Female, N (%)	682,062	365,012 (55%)	317,050 (53%)	< 0.0001
Male, N (%)	590,655	304,023 (45%)	286,632 (47%)
Race
White	797,383	451,028 (72%)	346,355 (62%)	< 0.0001
Black	215,822	85,997 (14%)	129,824 (23%)
Hispanic	115,739	61,225 (10 %)	54,513 (10%)
Asian	27,557	13,240 (2%)	14,317 (2%)
Others	35,109	17,427 (2%)	17,682 (3%)
Ulcerative colitis	10,242	4,869 (7%)	5,374(9%)	< 0.0001
Crohn’s disease	17,675	7,870 (1.2%)	9,805 (1.6%)	< 0.0001
Polypectomy	44,911	23,134 (3.4%)	21,777 (3.6%)	0.17
Stricture	5,443	2,587 (0.4%)	2,856 (0.5%)	0.002
Insurance
Medicare	808,730	440,454 (68%)	368,277 (63%)	< 0.0001
Medicaid	112,512	52,624 (8%)	59,888 (10%)
Private insurance	259,139	131,034 (20%)	128,106 (22%)
Self-pay/no charge/other	55,623	26,419 (4%)	29,204 (5%)
Elixhauser comorbidity index
0	59,210	33,157 (5%)	26,053 (4%)	< 0.0001
1 - 3	346,130	188,437 (28%)	157,693 (26%)
≥ 4	867,701	447,655 (67%)	420,046 (70%)

Table 1. Demographic Characteristics of Patients Who Underwent Colonoscopy Between 2010 and 2014 Stratified by Teaching vs. Non-Teaching Facilities

Variables

Total

Non-teaching

Teaching

P value

SD: standard deviation.

No. of observations, unweighted

257,006

135,652

121,354

No. of observations, weighted

1,273,042

669,250

603,792

Age, mean (SD)

68 (15)

66 (15)

< 0.0001

Sex

Female, N (%)

682,062

365,012 (55%)

317,050 (53%)

< 0.0001

Male, N (%)

590,655

304,023 (45%)

286,632 (47%)

Race

White

797,383

451,028 (72%)

346,355 (62%)

< 0.0001

Black

215,822

85,997 (14%)

129,824 (23%)

Hispanic

115,739

61,225 (10 %)

54,513 (10%)

Asian

27,557

13,240 (2%)

14,317 (2%)

Others

35,109

17,427 (2%)

17,682 (3%)

Ulcerative colitis

10,242

4,869 (7%)

5,374(9%)

< 0.0001

Crohn’s disease

17,675

7,870 (1.2%)

9,805 (1.6%)

< 0.0001

Polypectomy

44,911

23,134 (3.4%)

21,777 (3.6%)

0.17

Stricture

5,443

2,587 (0.4%)

2,856 (0.5%)

0.002

Insurance

Medicare

808,730

440,454 (68%)

368,277 (63%)

< 0.0001

Medicaid

112,512

52,624 (8%)

59,888 (10%)

Private insurance

259,139

131,034 (20%)

128,106 (22%)

Self-pay/no charge/other

55,623

26,419 (4%)

29,204 (5%)

Elixhauser comorbidity index

59,210

33,157 (5%)

26,053 (4%)

< 0.0001

1 - 3

346,130

188,437 (28%)

157,693 (26%)

≥ 4

867,701

447,655 (67%)

420,046 (70%)

**Table 2.** Univariate Odds Ratio for Perforation Post-Colonoscopy in Teaching Facilities Compared to Non-Teaching by Logistic Regression Model
Variables	Crude odds ratio with confidence interval	P value
Perforation	1.17 (1.02 - 1.34)	0.02
Age	1.00 (0.99 - 1)	0.39
Female sex	1.29 (1.12 - 1.47)	< 0.0001
Ulcerative colitis	2.67 (1.67 - 4.28)	< 0.0001
Crohn’s disease	2.71 (1.9 - 3.85)	< 0.0001
Dilatation of stricture	6.04 (3.92 - 9.31)	< 0.0001
Polypectomy	1.13 (0.81 - 1.59)	0.47
Race	0.88 (0.82 - 0.96)	0.005
Insurance
Medicare	Referent
Medicaid	0.81 (0.62 - 1)	0.12
Private insurance	1.04 (0.88 - 1.23)	0.59
Self-pay/no charge/other	0.78 (0.55 - 1.13)	0.196
Elixhauser comorbidity index
0	Referent
1 - 3	0.72 (0.54 - 0.96)	0.027
≥ 4	0.69 (0.52 - 0.90)	0.008

Table 2. Univariate Odds Ratio for Perforation Post-Colonoscopy in Teaching Facilities Compared to Non-Teaching by Logistic Regression Model

Variables

Crude odds ratio with confidence interval

P value

Perforation

1.17 (1.02 - 1.34)

0.02

Age

1.00 (0.99 - 1)

0.39

Female sex

1.29 (1.12 - 1.47)

< 0.0001

Ulcerative colitis

2.67 (1.67 - 4.28)

< 0.0001

Crohn’s disease

2.71 (1.9 - 3.85)

< 0.0001

Dilatation of stricture

6.04 (3.92 - 9.31)

< 0.0001

Polypectomy

1.13 (0.81 - 1.59)

0.47

Race

0.88 (0.82 - 0.96)

0.005

Insurance

Medicare

Referent

Medicaid

0.81 (0.62 - 1)

0.12

Private insurance

1.04 (0.88 - 1.23)

0.59

Self-pay/no charge/other

0.78 (0.55 - 1.13)

0.196

Elixhauser comorbidity index

Referent

1 - 3

0.72 (0.54 - 0.96)

0.027

≥ 4

0.69 (0.52 - 0.90)

0.008

**Table 3.** Multivariate Odds Ratio for Perforation Post-Colonoscopy in Teaching Facilities Compared to Non-Teaching by Logistic Regression Model
Variables	Adjusted odds ratio with confidence interval	P value
Teaching	1.23 (1.07 - 1.42)	0.004
Female sex	1.35 (1.16 - 1.56)	< 0.001
Ulcerative colitis	2.41 (1.46 - 3.97)	0.001
Crohn’s disease	2.40 (1.65 - 3.51)	< 0.001
Dilatation of stricture	5.19 (3.21 - 8.39)	< 0.001
Race
White	Referent
African-American	0.65 (0.53 - 0.80)	< 0.001
Hispanic	0.94 (0.74 - 1.20)	0.62
Asian	0.98 (0.62 - 1.56)	0.94
Others	0.45 (0.26 - 0.81)	0.007
Elixhauser comorbidity index
0	Referent
1 - 3	0.76 (0.56 - 1.05)	0.10
≥ 4	0.77 (0.57 - 1.04)	0.09

Table 3. Multivariate Odds Ratio for Perforation Post-Colonoscopy in Teaching Facilities Compared to Non-Teaching by Logistic Regression Model

Variables

Adjusted odds ratio with confidence interval

P value

Teaching

1.23 (1.07 - 1.42)

0.004

Female sex

1.35 (1.16 - 1.56)

< 0.001

Ulcerative colitis

2.41 (1.46 - 3.97)

0.001

Crohn’s disease

2.40 (1.65 - 3.51)

< 0.001

Dilatation of stricture

5.19 (3.21 - 8.39)

< 0.001

Race

White

Referent

African-American

0.65 (0.53 - 0.80)

< 0.001

Hispanic

0.94 (0.74 - 1.20)

0.62

Asian

0.98 (0.62 - 1.56)

0.94

Others

0.45 (0.26 - 0.81)

0.007

Elixhauser comorbidity index

Referent

1 - 3

0.76 (0.56 - 1.05)

0.10

≥ 4

0.77 (0.57 - 1.04)

0.09