Disparities in colonoscopy utilization for lower gastrointestinal bleeding in rural vs urban settings in the United States

Table 1 Characteristics of patients admitted for lower gastrointestinal bleeding, stratified by geography

Variable	Urban (n = 141571)	Rural (n = 16177)	P value
Age	73.01	74.35	< 0.0001
18-64	24.2%	20.3%
65-74	22.2%	22.3%
75-84	27.6%	29.6%
85+	22.9%	24.5%
Sex			< 0.0001
Male	48.1%	46.3%
Female	51.9%	53.7%
Race			< 0.0001
White	63.9%	74.6%
Black	18.5%	10.8%
Hispanic	8.2%	2.3%
Asian	2.7%	1.9%
Other	2.1%	1.0%
Missing	4.6%	9.4%
Payer			< 0.0001
Medicare	74.3%	78.8%
Medicaid	5.4%	4.3%
Commercial	16.0%	12.4%
Other	4.3%	4.4%
Missing	0.1%	0.3%
Comorbidities
Number	1.38	1.32	< 0.0001
Charlson index	1.89	1.77	< 0.0001
Colonoscopy			< 0.0001
Yes	45.1%	37.9%
No	54.9%	62.1%
Hospital bed size			< 0.0001
Small	15.5%	10.8%
Medium	29.5%	18.9%
Large	54.9%	70.2%
Region			< 0.0001
Northeast	33.2%	21.8%
Midwest	44.2%	20.8%
South	50.0%	39.9%
West	28.4%	17.4%
Teaching			< 0.0001
No	45.5%	100.0%
Yes	54.5%	0.0%

Table 2 Results of multivariable model of colonoscopy utilization

Variable	OR	95%CI		P value
		Lower	Upper
Rural	0.730	0.705	0.757	< 0.0001
Age
18-64	Reference
65-74	0.978	0.946	1.010	0.177
75-84	0.986	0.954	1.018	0.384
85+	0.826	0.798	0.855	< 0.0001
Sex
Male	Reference
Female	0.956	0.937	0.976	< 0.0001
Race
White	Reference
Black	1.224	1.191	1.258	< 0.0001
Hispanic	1.206	1.160	1.253	< 0.0001
Asian	1.222	1.148	1.301	< 0.0001
Other	1.158	1.078	1.244	< 0.0001
Missing	1.107	1.057	1.159	< 0.0001
Payer
Medicare	Reference
Medicaid	0.986	0.938	1.037	0.590
Commercial	1.068	1.034	1.103	< 0.0001
Other	1.076	1.020	1.135	0.007
Missing	0.763	0.579	1.004	0.053
Hospital bed size
Small	0.899	0.873	0.925	< 0.0001
Medium	0.919	0.898	0.940	< 0.0001
Large	Reference
Teaching
No	Reference
Yes	0.951	0.931	0.972	< 0.0001
Charlson comorbidity index	0.949	0.944	0.955	< 0.0001

Table 3 Multivariable model of mortality

Variable	OR	95%CI		P value
		Lower	Upper
Rural	1.050	0.888	1.242	0.567
Colonoscopy
Yes	0.498	0.446	0.557	< 0.0001
No	Reference
Age
18-64	Reference
65-74	0.939	0.780	1.130	0.504
75-84	1.333	1.121	1.584	0.001
85+	2.132	1.797	2.530	< 0.0001
Sex
Male	Reference
Female	0.828	0.749	0.915	< 0.0001
Race
White	Reference
Black	0.961	0.835	1.106	0.579
Hispanic	0.694	0.556	0.867	0.001
Asian	1.063	0.784	1.443	0.693
Other	0.960	0.665	1.385	0.826
Missing	0.944	0.750	1.187	0.621
Payer
Medicare	Reference
Medicaid	0.941	0.718	1.235	0.662
Commercial	0.834	0.695	1.002	0.052
Other	0.774	0.556	1.077	0.129
Missing	0.538	0.074	3.905	0.540
Hospital bed size
Small	0.911	0.786	1.057	0.218
Medium	0.966	0.862	1.083	0.552
Large	Reference
Teaching
No	Reference
Yes	0.987	0.887	1.099	0.813
Charlson comorbidity index	1.239	1.215	1.263	< 0.0001

Table 4 Multivariable model of length of hospital stay

Variable	Coefficient	95%CI		P value
		Lower	Upper
Rural	-0.372	-0.444	-0.300	< 0.0001
Colonoscopy
Yes	0.718	0.677	0.759	< 0.0001
No	Reference
Age
18-64	Reference
65-74	0.133	0.066	0.201	< 0.0001
75-84	0.382	0.315	0.449	< 0.0001
85+	0.518	0.448	0.588	< 0.0001
Sex
Male	Reference
Female	0.067	0.026	0.109	0.001
Race
White	Reference
Black	0.590	0.534	0.646	< 0.0001
Hispanic	0.016	-0.064	0.095	0.699
Asian	-0.041	-0.169	0.088	0.534
Other	0.091	-0.057	0.238	0.227
Missing	-0.183	-0.277	-0.089	< 0.0001
Payer
Medicare	Reference
Medicaid	-0.047	-0.150	0.055	0.367
Commercial	-0.386	-0.453	-0.319	< 0.0001
Other	-0.403	-0.513	-0.292	< 0.0001
Missing	-0.079	-0.631	0.473	0.779
Hospital bed size
Small	-0.451	-0.511	-0.391	< 0.0001
Medium	-0.235	-0.283	-0.188	< 0.0001
Large	Reference
Teaching
No	Reference
Yes	0.297	0.253	0.341	< 0.0001
Charlson comorbidity index	0.232	0.221	0.243	< 0.0001
Intercept	3.173	3.097	3.249	< 0.0001

Table 5 Multivariable model of inpatient admission costs

Variable	Coefficient	95%CI		P value
		Lower	Upper
Rural	-$853.03	-$1059.62	-$646.44	< 0.0001
Colonoscopy
Yes	$2198.68	$2080.08	$2317.27	< 0.0001
No	Reference
Age
18-64	Reference
65-74	$353.75	$159.71	$547.79	< 0.0001
75-84	$569.47	$377.06	$761.87	< 0.0001
85+	$184.80	-$16.82	$386.42	0.072
Sex
Male	Reference
Female	-$487.40	-$606.30	-$368.49	< 0.0001
Race
White	Reference
Black	$1065.28	$903.76	$1226.81	< 0.0001
Hispanic	$571.60	$343.11	$800.10	< 0.0001
Asian	$2228.13	$1858.86	$2597.39	< 0.0001
Other	$938.42	$514.93	$1361.92	< 0.0001
Missing	-$223.19	-$492.88	$46.49	0.105
Payer
Medicare	Reference
Medicaid	$209.94	-$85.38	$505.27	0.164
Commercial	-$432.66	-$624.55	-$240.77	< 0.0001
Other	-$788.60	-$1105.57	-$471.62	< 0.0001
Missing	-1065.893	-2652.626	520.839	0.188
Hospital bed size
Small	-$418.08	-$590.47	-$245.70	< 0.0001
Medium	-$305.15	-$440.76	-$169.54	< 0.0001
Large	Reference
Teaching
No	Reference
Yes	$604.62	$477.91	$731.33	< 0.0001
Charlson comorbidity index	$601.63	$570.19	$633.06	< 0.0001
Intercept	$7859.86	$7642.30	$8077.41	< 0.0001