Real-world retrospective analysis of patient characteristics, healthcare resource utilization, costs, and treatment patterns among unvaccinated adults with COVID-19 diagnosed in outpatient settings in the United States

Figures & data

Figure 1. Study scheme. The follow-up period varied by patient, began after the index date, and continued until insurance dis-enrollment, or the end of the study period, whichever was earliest.

Figure 2. Patient disposition. COVID-19, coronavirus disease 2019.

Table 1. Patient demographic and baseline clinical characteristics.

	All patients (N = 236,589)		Patients not requiring inpatient admission (n = 228,897)		Patients requiring inpatient admission anytime during follow-up (n = 7,692)
Characteristic	n	%	n	%	n	%
Age, years
Median, Q1–Q3	51	35–68	50	34–67	68	56–76
Mean, SD	50.95	18.97	50.48	18.91	65.00	14.88
Age group, years
18–29	40,412	17.08	40,209	17.57	203	2.64
30–49	71,408	30.18	70,393	30.75	1,015	13.20
50–64	53,863	22.77	52,019	22.73	1,844	23.97
65–74	43,372	18.33	40,927	17.88	2,445	31.79
75+	27,534	11.64	25,349	11.07	2,185	28.41
Sex
Female	125,601	53.09	122,037	53.32	3,564	46.33
Male	110,985	46.91	106,857	46.68	4,128	53.67
Unknown	3	0.00	3	0.00	0	0.00
Race
White	121,621	51.41	118,141	51.61	3,480	45.24
Hispanic	37,453	15.83	36,022	15.74	1,431	18.60
Black	18,643	7.88	17,853	7.80	790	10.27
Asian	6,246	2.64	6,091	2.66	155	2.02
Unknown	52,626	22.24	50,790	22.19	1,836	23.87
Division
South Atlantic	48,381	20.45	46,412	20.28	1,969	25.60
West South Central	45,449	19.21	43,732	19.11	1,717	22.32
East North Central	35,035	14.81	33,877	14.80	1,158	15.05
West North Central	30,428	12.86	29,601	12.93	827	10.75
Mountain	25,944	10.97	25,313	11.06	631	8.20
Mid-Atlantic	20,377	8.61	20,000	8.74	377	4.90
Pacific	14,214	6.01	13,795	6.03	419	5.45
East South Central	9,969	4.21	9,559	4.18	410	5.33
New England	6,538	2.76	6,355	2.78	183	2.38
Unknown	254	0.11	253	0.11	1	0.01
Insurance type
Commercial	160,396	67.80	157,763	68.92	2,633	34.23
Medicare	76,177	32.20	71,118	31.07	5,059	65.77
Unknown	16	0.01	16	0.01	0	0.00
Antithrombotic therapy at baseline
Any antithrombotic therapy	12,981	5.49	11,937	5.22	1,044	13.57
Low–molecular-weight heparin^a	6,071	2.57	5,537	2.42	534	6.94
Factor Xa inhibitor^b	5,949	2.51	5,503	2.40	446	5.80
Warfarin	2,033	0.86	1,875	0.82	158	2.05
Thrombin inhibitor^c	542	0.23	506	0.22	36	0.47
Comorbidities at baseline^d
Gastrointestinal condition	82,839	35.01	78,942	34.49	3,897	50.66
Obesity	63,562	26.87	60,386	26.38	3,176	41.29
Chronic lung diseases	14,769	6.24	13,709	5.99	1,060	13.78
COPD, emphysema, and chronic bronchitis	8,986	3.80	8,353	3.65	633	8.23
Rheumatic disease	8,720	3.69	8,261	3.61	459	5.97
Asthma (moderate or severe)	3,056	1.29	2,859	1.25	197	2.56
Pulmonary hypertension	2,480	1.05	2,224	0.97	256	3.33
Interstitial lung disease, pulmonary fibrosis	1,861	0.79	1,687	0.74	174	2.26
Solid organ or blood stem cell transplant	198	0.08	166	0.07	32	0.42
Cystic fibrosis	38	0.02	38	0.02	0	0.00
≥1 Characteristic or underlying medical condition  associated with a higher risk of COVID-19	171,252	72.38	164,069	71.68	7,183	93.38
Immune deficiencies/immunocompromised state	121,939	51.54	116,405	50.85	5,534	71.94
Hypertension	88,229	37.29	82,952	36.24	5,277	68.60
≥65 years of age	70,906	29.97	66,276	28.95	4,630	60.19
Obesity	63,562	26.87	60,386	26.38	3,176	41.29
CVD combined	43,686	18.46	40,539	17.71	3,147	40.91
Diabetes (type 1 or 2)	41,186	17.41	38,075	16.63	3,111	40.44
Current or former smoker	24,809	10.49	23,310	10.18	1,499	19.49
Cancer history	21,718	9.18	20,381	8.90	1,337	17.38
Chronic kidney disease	18,397	7.78	16,632	7.27	1,765	22.95
Chronic lung diseases	14,769	6.24	13,709	5.99	1,060	13.78
Stroke or cerebrovascular disease	9,628	4.07	8,928	3.90	700	9.10
Dementia or other neurologic condition	5,952	2.52	5,537	2.42	415	5.40
Pregnancy and recent pregnancy	4,679	1.98	4,476	1.96	203	2.64
Substance use disorder	4,649	1.97	4,420	1.93	229	2.98
Liver disease	1,402	0.59	1,297	0.57	105	1.37
HIV infection	777	0.33	756	0.33	21	0.27
Sickle cell disease or thalassemia	452	0.19	426	0.19	26	0.34
Solid organ or blood stem cell transplant	198	0.08	166	0.07	32	0.42
Down syndrome	68	0.03	63	0.03	5	0.07

Abbreviations. COPD, chronic obstructive pulmonary disease; COVID-19, coronavirus disease 2019; CVD, cardiovascular disease; Q1, first quartile; Q3, third quartile.

^aEnoxaparin, dalteparin, and heparin.

^bApixaban, fondaparinux, rivaroxaban, and edoxaban.

^cBivalirudin, argatroban, dabigatran, and antithrombin III.

^dIncludes baseline COVID-19 risk conditions.

Data by time to admission are in Supplementary Table 2.

Table 2. COVID-19–related outpatient HCRU.

	All patients (N = 236,589)		Patients not requiring inpatient admission (n = 228,897)		Patients requiring inpatient admission anytime during follow-up (n = 7,692)
Number of outpatient visits
Patients, n (%)	236,589	(100)	228,897	(100)	7,692	(100)
Median, Q1–Q3	1	1–2	1	1–2	5	3–10
Mean, SD	2.27	3.32	2.08	2.78	7.83	8.79
Number of telehealth visits
Patients, n (%)	236,589	(100)	228,897	(100)	7,692	(100)
Median, Q1–Q3	0	0–0	0	0–0	0	0–0
Mean, SD	0.03	0.27	0.03	0.24	0.11	0.73
Number of urgent care visits
Patients, n (%)	236,589	(100)	228,897	(100)	7,692	(100)
Median, Q1–Q3	0	0–0	0	0–0	0	0–0
Mean, SD	0.06	0.29	0.06	0.29	0.12	0.39
Number of ED visits
Patients, n (%)	236,589	(100)	228,897	(100)	7,692	(100)
Median, Q1–Q3	0	0–0	0	0–0	0	0–1
Mean, SD	0.20	0.48	0.19	0.46	0.58	0.72

Abbreviations. COVID-19, coronavirus disease 2019; ED, emergency department; HCRU, healthcare resource utilization; Q1, first quartile; Q3, third quartile.

Data by time to admission are in Supplementary Table 7.

Figure 3. COVID-19–related HCRU among patients with inpatient hospital admission(s). Abbreviations. COVID-19, coronavirus disease 2019; ICU, intensive care unit; LOS, length of stay; Q1, first quartile; Q3, third quartile.

Table 3. COVID-19–related inpatient HCRU.

	All patients (N = 236,589)		Patients not requiring inpatient admission (n = 228,897)		Patients requiring inpatient admission anytime during follow-up (n = 7,692)
Number of inpatient visits
Median, Q1–Q3	0	0–0	0	0–0	1	1–1
Mean, SD	0.04	0.21	0.00	0.00	1.10	0.35
Days from outpatient diagnosis to inpatient admission
Patients, n (%)	7,692	(3.3)	0	(0)	7,692	(100)
Median,  Q1–Q3	7	5–11	–	–	7	5–11
Mean, SD	18.98	38.26	–	–	18.98	38.26
Inpatient LOS
Patients, n (%)	7,692	(3.3)	0	(0)	7,692	(100)
Median, Q1–Q3	6	4–9	–	–	6	4–9
Mean, SD	7.86	7.21	–	–	7.86	7.21
Inpatient non-ICU LOS
Patients, n (%)	5,131	(2.2)	0	(0)	5,131	(66.7)
Median, Q1–Q3	5	4–7	–	–	5	4–7
Mean, SD	6.31	4.29	–	–	6.31	4.29
Inpatient ICU LOS
Patients with ICU admission, n (%)	2,561	(1.1)	–	–	2,561	(33.3)
Median, Q1–Q3	8	5–13	–	–	8	5–13
Mean, SD	10.96	10.24	–	–	10.96	10.24

Abbreviations. COVID-19, coronavirus disease 2019; HCRU, healthcare resource utilization; ICU, intensive care unit; LOS, length of stay; Q1, first quartile; Q3, third quartile.

Data by time to admission are in Supplementary Table 10.

Table 4. COVID-19 treatment characteristics.

	All patients (N = 236,589)		Patients not requiring inpatient admission (n = 228,897)		Patients requiring inpatient admission anytime during follow-up (n = 7,692)
Treatment characteristic	n	%	n	%	n	%
Invasive mechanical ventilation during COVID-19–related hospitalization^a	646	0.27	0	0	648	8.42
Noninvasive mechanical ventilation during COVID-19–related hospitalization	546	0.23	0	0	546	7.10
Supplemental oxygen during COVID-19–related hospitalization	1,022	0.43	0	0	1,022	13.29
Death after discharge from COVID-19–related hospitalization	461	0.19	0	0	461	5.99
All-cause inpatient readmission after discharge from COVID-19–related hospitalization	1,041	0.44	0	0	1,041	13.53
Mortality during follow-up	1,246	0.53	785	0.34	461	5.99
Discharge status from COVID-19–related hospitalization
Discharged to home or self-care (routine discharge)	5,189	2.19	0	0.00	5,189	67.46
Discharged to home under care of home health service organization	1,357	0.57	0	0.00	1,357	17.64
Discharged/transferred to a short-term general hospital for inpatient care	135	0.06	0	0.00	135	1.76
Discharged/transferred to long-term care hospital	46	0.02	0	0.00	46	0.60
Discharged to home hospice	33	0.01	0	0.00	33	0.43
Discharged to medical hospice facility	30	0.01	0	0.00	30	0.39
Discharged/transferred to skilled nursing facility with Medicare	30	0.01	0	0.00	30	0.39
Left against medical advice or discontinued care	30	0.01	0	0.00	30	0.39
Transferred to intermediate care facility	15	0.01	0	0.00	15	0.20
Not discharged or expected to return for outpatient services	14	0.01	0	0.00	14	0.18
Discharged/transferred to an inpatient rehabilitation facility inc [sic] hospital	11	0.00	0	0.00	11	0.14
Discharged/transferred within institution	7	0.00	0	0.00	7	0.09
Reserved for national assignment	6	0.00	0	0.00	6	0.08
Discharged/transferred to a psychiatric hospital or dist pt [sic]	4	0.00	0	0.00	4	0.05
Discharged/transferred to another type of healthcare institution	4	0.00	0	0.00	4	0.05
Discharge/transferred to a critical access hospital	2	0.00	0	0.00	2	0.03
Discharged/transferred to a nursing facility certified under Medicare	2	0.00	0	0.00	2	0.03
Admitted as inpatient to this hospital	1	0.00	0	0.00	1	0.01
Patients treated in an outpatient setting only	228,897	96.75	228,897	100.00	0	0.00
Not available from the source	416	0.18	0	0.00	416	5.41
Unknown discharge status	360	0.15	0	0.00	360	4.68

Abbreviation. COVID-19, coronavirus disease 2019.

^aIncludes extracorporeal membrane oxygenation.

Data by time to admission are in Supplementary Table 12.

Table 5. COVID-19–related outpatient and inpatient costs.

Cost	All patients (N = 236,589)		Patients not requiring inpatient admission (n = 228,897)		Patients requiring inpatient admission anytime during follow-up (n = 7,692)
Standard cost of outpatient encounters, N, missing value	236,589	0	228,897	0	7,692	0
Median, Q1–Q3	$198	$118–$493	$194	$117–$437	$2,274	$618–$4,943
Mean, SD	$1,077	$6,993	$901	$4,272	$6,300	$30,542
Standard cost of telehealth visits, N, missing value	236,589	0	228,897	0	7,692	0
Median, Q1–Q3	$0	$0–$0	$0	$0–$0	$0	$0–$0
Mean, SD	$3	$30	$3	$26	$12	$84
Standard cost of urgent care visits, N, missing value	236,589	0	228,897	0	7,692	0
Median, Q1–Q3	$0	$0–$0	$0	$0–$0	$0	$0–$0
Mean, SD	$15	$85	$14	$83	$32	$130
Standard cost of outpatient ED visits	236,589	0	228,897	0	7,692	0
Median, Q1–Q3	$0	$0–$0	$0	$0–$0	$0	$0–$1,762
Mean, SD	$337	$1,119	$313	$1,066	$1,055	$2,043
Standard cost of inpatient encounters, N, missing value	236,589	0	228,897	0	7,692	0
Median, Q1–Q3	$0	$0–$0	$0	$0–$0	$36,459	$32,866 – $38,382
Mean, SD	$1,407	$10,945	$0	$0	$43,289	$43,261
Standard cost of prescription claims, N, missing value	236,589	0	228,897	0	7,692	0
Median, Q1–Q3	$0	$0–$9	$0	$0–$8	$19	$3–$99
Mean, SD	$79	$460	$71	$441	$319	$822
Total standard medical costs (prescription claims, inpatient, and outpatient encounters), N, missing value	236,589	0	228,897	0	7,692	0
Median, Q1–Q3	$219	$124–$611	$208	$121–$509	$39,187	$36,071–$44,994
Mean, SD	$2,563	$13,969	$972	$4,309	$49,908	$55,970
Non-zero standard cost of outpatient encounters, N, missing value	236,431	158	228,741	156	7,690	2
Median, Q1–Q3	$199	$118–$494	$194	$118–$438	$2,276	$618–$4,944
Mean, SD	$1,077	$6,995	$902	$4,273	$6,302	$30,546
Non-zero standard cost of telehealth visits, N, missing value	5,670	230,919	5,140	223,757	530	7,162
Median, Q1–Q3	$85	$60–$128	$84	$60–$126	$126	$81–$212
Mean, SD	$123	$151	$118	$132	$180	$267
Non-zero standard cost of urgent care visits, N, missing value	13,013	223,576	12,234	216,663	779	6,913
Median, Q1–Q3	$194	$128–$318	$194	$128–$311	$241	$158–$384
Mean, SD	$272	$246	$269	$244	$318	$275
Non-zero standard cost of outpatient ED visits, N, missing value	40,485	196,104	36,871	192,026	3,614	4,078
Median, Q1–Q3	$1,635	$1,029–$2,489	$1,608	$1,011–$2,466	$1,844	$1,131–$2,700
Mean, SD	$1,967	$2,027	$1,940	$1,974	$2,245	$2,492
Non-zero standard cost of inpatient encounters, N, missing value	7,687	228,902	0	228,897	7,687	5
Median, Q1–Q3	$36,460	$32,891–$38,386	–	–	$36,460	$32,891–$38,386
Mean, SD	$43,317	$43,261	–	–	$43,317	$43,261
Non-zero standard cost of prescription claims, N, missing value	84,974	151,615	79,074	149,823	5,900	1,792
Median, Q1–Q3	$17	$8–$39	$16	$8–$36	$34	$13–$313
Mean, SD	$219	$748	$205	$732	$416	$917
Total non-zero standard medical costs (prescription claims, inpatient, and outpatient encounters), N, missing value	236,493	96	$228,801	96	7,692	0
Median, Q1–Q3	$220	$124–$611	$208	$121–$509	$39,187	$36,071–$44,994
Mean, SD	$2,564	$13,971	$972	$4,310	$49,908	$55,970

Abbreviations. COVID-19, coronavirus disease 2019; ED, emergency department; Q1, first quartile; Q3, third quartile.

Data by time to admission are in Supplementary Table 14.

Table 6. Clinical characteristics of patients hospitalized and not hospitalized with COVID-19 infection.

	All patients (N = 236,589)		Patients not requiring inpatient admission (n = 228,897)		Patients requiring inpatient admission anytime during follow-up (n = 7,692)
Characteristic	n	%	N	%	n	%
Hypertension	80,092	33.85	74,079	32.36	6,013	78.17
Gastrointestinal condition	68,675	29.03	63,625	27.80	5,050	65.65
Obesity	48,755	20.61	44,941	19.63	3,814	49.58
Cardiovascular disease	41,914	17.72	37,270	16.28	4,644	60.37
Diabetes	39,118	16.53	35,559	15.53	3,559	46.27
Cancer history	18,258	7.72	16,803	7.34	1,455	18.92
Chronic kidney disease	16,741	7.08	14,567	6.36	2,174	28.26
Chronic lung disease	12,171	5.14	10,497	4.59	1,674	21.76
Cerebrovascular disease	7,532	3.18	6,701	2.93	831	10.80
Rheumatic disease	7,136	3.02	6,681	2.92	455	5.92
COPD	6,281	2.65	5,454	2.38	827	10.75
Neurologic disease	5,559	2.35	4,961	2.17	598	7.77
Asthma (moderate or severe)	2,641	1.12	2,394	1.05	247	3.21
Pulmonary hypertension	2,332	0.99	1,908	0.83	424	5.51
Interstitial lung disease, pulmonary fibrosis	2,248	0.95	1,745	0.76	503	6.54
Chronic liver disease	1,271	0.54	1,119	0.49	152	1.98
HIV infection	707	0.30	682	0.30	25	0.33
Sickle cell/anemia disease	364	0.15	333	0.15	31	0.40
Organ/stem cell transplantation	148	0.06	116	0.05	32	0.42
Cystic fibrosis	33	0.01	30	0.01	3	0.04

Abbreviations. COPD, chronic obstructive pulmonary disease; COVID-19, coronavirus disease 2019.

Data by time to admission are in Supplementary Table 19.

Data availability statement

The data that support the findings of this study are available from the corresponding author, AMS, upon reasonable request.