Comparison of hospital length of stay and hospitalization costs among patients with non-valvular atrial fibrillation treated with apixaban or warfarin: An early view

Figures & data

Table 1. Baseline characteristics of hospitalized NVAF patients treated with apixaban and warfarin.

	Apixaban (n = 2894)		Warfarin(n = 124,174)		p-value
	n/Mean	%/SD	n/Mean	%/SD
Age	73.2	11.7	75.1	11.0	<0.001
18–64	622	21.5%	21,047	16.9%	<0.001
65–74	808	27.9%	30,798	24.8%	<0.001
75+	1464	50.6%	72,329	58.2%	<0.001
Gender
Male	1462	50.5%	65,659	52.9%	0.012
Female	1432	49.5%	58,507	47.1%	0.012
Race
White	2423	83.7%	96,156	77.4%	<0.001
Black	149	5.1%	9,320	7.5%	<0.001
Other	322	11.1%	18,698	15.1%	<0.001
Insurance coverage
Managed	511	17.7%	13,021	10.5%	<0.001
Government	2300	79.5%	107,851	86.9%	<0.001
Indigent/Charity	10	0.3%	387	0.3%	0.747
Other	73	2.5%	2915	2.3%	0.539
Admission type
Emergency	2007	69.4%	87,928	70.8%	0.088
Urgent	377	13.0%	16,569	13.3%	0.621
Elective	479	16.6%	18,891	15.2%	0.048
Trauma center	9	0.3%	329	0.3%	0.635
Unknown	22	0.8%	457	0.4%	0.001
Discharge type
Expired	43	1.5%	2,449	2.0%	0.062
Discharged	2843	98.2%	120,988	97.4%	0.007
Other	8	0.3%	737	0.59%	0.028
Hospital characteristics
US Region
Northeast	397	13.7%	29,773	24.0%	<0.001
Midwest	740	25.6%	30,006	24.2%	0.081
South	1553	53.7%	46,799	37.7%	<0.001
West	204	7.0%	17,596	14.2%	<0.001
Population served
Urban	2325	80.3%	105,987	85.4%	<0.001
Rural	569	19.7%	18,187	14.6%	<0.001
Hospital setting
Teaching	1139	39.4%	49,473	39.8%	0.599
Non-teaching	1755	60.6%	74,701	60.2%	0.599
Hospital bed size
<100	155	5.4%	6,304	5.1%	0.499
100–199	350	12.1%	16,684	13.4%	0.036
200–299	569	19.7%	22,429	18.1%	0.027
300–499	983	34.0%	43,232	34.8%	0.343
≥500	837	28.9%	35,525	28.6%	0.713
Any hospitalization 12-months prior to index hospitalization	370	12.8%	30,793	24.8%	<0.001
Baseline Comorbidity
Deyo-Charlson Comorbidity Index	2.1	2.0	2.8	2.2	<0.001
CHADS2 Score	2.4	1.4	2.7	1.3	<0.001
0 = low risk	159	5.5%	3,533	2.8%	<0.001
1 = moderate risk	585	20.2%	16,806	13.5%	<0.001
2 = high risk	887	30.6%	36,167	29.1%	0.075
<2 = high risk	1263	43.6%	67,668	54.5%	<0.001
CHA2DS2-VASc Score	3.9	1.8	4.3	1.7	<0.001
0 = low risk	69	2.4%	1,001	0.8%	<0.001
1 = moderate risk	194	6.7%	4,339	3.5%	<0.001
2 = high risk	335	11.6%	11,298	9.1%	<0.001
<2 = high risk	2296	79.3%	107,536	86.6%	<0.001
HAS-BLED Score	3.1	1.2	3.3	1.2	<0.001
Congestive Heart Failure	1064	36.8%	59,130	47.6%	<0.001
Diabetes Mellitus	942	32.6%	49,606	39.9%	<0.001
Hypertension	2373	82.0%	103,907	83.7%	<0.001
Ischemic Stroke	294	10.2%	11,281	9.1%	0.047
Transient Ischemic Attack	79	2.7%	2,771	2.2%	0.074
Stroke	594	20.5%	27,886	22.5%	<0.001
Vascular Disease	1209	41.8%	62,920	50.7%	<0.001
Renal Insufficiency	830	28.7%	51,027	41.1%	<0.001
Venous Thromboembolism	24	0.8%	8,498	6.8%	<0.001
Acute Coronary Syndrome	241	8.3%	10,010	8.1%	0.603
Drug and Alcohol Use	411	14.2%	14,283	11.5%	<0.001
Chronic Kidney Disease	582	20.1%	39,476	31.8%	<0.001
Chronic Obstructive Pulmonary  Disease	649	22.4%	33,646	27.1%	<0.001
Anemia	646	22.3%	44,060	35.5%	<0.001

CHADS₂, congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism; CHA₂DS₂-VASc, CHADS₂ plus vascular disease, age 65–74 years, sex category; NVAF, non-valvular atrial fibrillation; SD, standard deviation.

Table 2. Baseline characteristics of hospitalized NVAF patients treated with apixaban and warfarin after 1:1 PSM.

	Apixaban		Warfarin		Std difference
	(n = 2886)		(n = 2886)
	n/Mean	%/SD	n/Mean	%/SD
Age	73.3	11.6	73.3	11.4	0.00
18–64	614	21.3%	589	20.4%	0.02
65–74	808	28.0%	823	28.5%	0.01
75+	1464	50.7%	1474	51.1%	0.01
Gender
Male	1454	50.4%	1494	51.8%	0.03
Female	1432	49.6%	1392	48.2%	0.03
Race
White	2415	83.7%	2421	83.9%	0.01
Black	149	5.2%	145	5.0%	0.01
Other	322	11.2%	320	11.1%	0.00
Insurance Coverage
Managed	503	17.4%	495	17.2%	0.01
Government	2300	79.7%	2308	80.0%	0.01
Indigent/Charity	10	0.3%	12	0.4%	0.01
Other	73	2.5%	71	2.5%	0.00
Admission Type
Emergency	2000	69.3%	2014	69.8%	0.01
Urgent	377	13.1%	364	12.6%	0.01
Elective	479	16.6%	477	16.5%	0.00
Trauma center	9	0.3%	11	0.4%	0.01
Unknown	21	0.7%	20	0.7%	0.00
Discharge Type
Discharged	2835	98.2%	2821	97.7%	0.03
Expired	43	1.5%	46	1.6%	0.01
Other	8	0.3%	19	0.7%	0.06
Hospital characteristics
Region
Northeast	397	13.8%	407	14.1%	0.01
Midwest	738	25.6%	738	25.6%	0.00
South	1547	53.6%	1553	53.8%	0.00
West	204	7.1%	188	6.5%	0.02
Population served
Urban	2318	80.3%	2342	81.2%	0.02
Rural	568	19.7%	544	18.8%	0.02
Hospital setting
Teaching	1134	39.3%	1133	39.3%	0.00
Non-teaching	1752	60.7%	1753	60.7%	0.00
Hospital bed size
<100	155	5.4%	148	5.1%	0.01
100–199	350	12.1%	354	12.3%	0.00
200–299	569	19.7%	559	19.4%	0.01
300–499	980	34.0%	958	33.2%	0.02
≥500	832	28.8%	867	30.0%	0.03
Any hospitalization 12 months prior to index hospitalization	370	12.8%	361	12.5%	0.01
Baseline Comorbidity
Deyo-Charlson Comorbidity Index score	2.1	2.0	2.2	2.0	0.03
CHADS2 score	2.4	1.3	2.4	1.3	0.01
0 = low risk	151	5.2%	167	5.8%	0.02
1 = moderate risk	585	20.3%	541	18.7%	0.04
2 = high risk	887	30.7%	882	30.6%	0.00
<2 = high risk	1263	43.8%	1296	44.9%	0.02
CHADS2-VASc score	3.9	1.8	3.9	1.7	0.00
0 = low risk	61	2.1%	70	2.4%	0.02
1 = moderate risk	194	6.7%	180	6.2%	0.02
2 = high risk	335	11.6%	320	11.1%	0.02
<2 = high risk	2296	79.6%	2316	80.2%	0.02
HAS-BLED Score	3.1	1.2	3.1	1.2	0.02
Congestive Heart Failure	1064	36.9%	1081	37.5%	0.01
Diabetes Mellitus	942	32.6%	946	32.8%	0.00
Hypertension	2373	82.2%	2376	82.3%	0.00
Ischemic Stroke	294	10.2%	285	9.9%	0.01
Transient Ischemic Attack	79	2.7%	57	2.0%	0.05
Stroke	594	20.6%	565	19.6%	0.03
Vascular Disease	1209	41.9%	1220	42.3%	0.01
Renal Insufficiency	829	28.7%	846	29.3%	0.01
Venous Thromboembolism	24	0.8%	28	1.0%	0.01
Acute Coronary Syndrome	241	8.4%	261	9.0%	0.02
Drug and Alcohol Use	407	14.1%	400	13.9%	0.01
Chronic Kidney Disease	582	20.2%	601	20.8%	0.02
Chronic Obstructive Pulmonary Disease	649	22.5%	665	23.0%	0.01
Anemia	646	22.4%	654	22.7%	0.01
Hemodialysis	16	0.6%	17	0.6%	0.00
Thrombocytopenia	132	4.6%	146	5.1%	0.02

CHADS₂, congestive heart failure, hypertension, age ≥75years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism; CHADS₂-VASc, CHADS₂ plus vascular disease, age 65–74 years, sex category; HAS-BLED, hypertension, abnormal renal and liver function, stroke, bleeding, labile International Normalized Ratios, elderly age (≥65 years), drug therapy and alcohol intake; NVAF, non-valvular atrial fibrillation; PSM, propensity score matching; SD, standard deviation; Std. Difference: standardized difference.

Figure 1. Average hospital LOS for NVAF patients. LOS, length of stay; NVAF, non-valvular atrial fibrillation.

Table 3. Outcomes of hospitalized NVAF patients treated with apixaban and warfarin after 1:1 PSM.

	Apixaban (n = 2886)		Warfarin (n = 2886)		p-value
	n/Mean	%/SD	n/Mean	%/SD
Index Hospitalization Length of Stay
Hospital Length of Stay (in days)	5.1	5.7	5.5	4.8	0.002
Median	3.0		4.0
0–2	939	32.5%	712	24.7%	<0.001
3–7	1444	50.0%	1582	54.8%	<0.001
8–14	360	12.5%	448	15.5%	0.001
15–30	128	4.4%	130	4.5%	0.899
>30	15	0.5%	14	0.5%	0.848
Hospital LOS from point of apixaban or warfarin administration to discharge	4.5	5.5	4.7	4.6	0.051
Index Hospitalization Health Care Costs	$11,262	$14,048	$12,883	$15,702	<0.001
Hospital Length of Stay (in days)
0–2	$5033	$5400	$5797	$6,189	0.041
3–7	$9554	$9255	$10,179	$7,176	<0.001
8–14	$21,008	$13,610	$22,386	$13,424	0.004
15–30	$39,381	$18,574	$42,764	$34,660	0.505
>30	$91,774	$49,843	$97,273	$69,917	0.981
CHADS2 Score
0–1 (low-to-moderate risk)	$9855	$11,275	$12,713	$14,996	0.004
≥2 (high-risk)	$11,744	$14,850	$12,938	$15,927	0.006
All-cause re-admission
Patients with 30 days of follow-up	2839	98.4%	2841	98.1%	0.424
Re-admission within 30 days	291	10.3%	306	10.8%	0.493

NVAF, non-valvular atrial fibrillation; PSM, propensity score matching; SD, standard deviation; CHADS₂, congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism.

Figure 2. Average index hospitalization costs for NVAF patients.