The real-world economic impact of home-based video electroencephalography: the payer perspective

Figures & data

Table 1. Attrition table for inpatient and outpatient video EEG.

Attrition	All patients
	n	%
Patients receiving VEEG services during the identification period from July 1, 2013 to December 31, 2016	48,176	100%
Inpatient VEEG	23,710	49%
Outpatient VEEG	24,354	51%
Both	112	0%
Patients who had both places of service indicated on index date were excluded below from the final patient sample
Exclusion
Less than 3 years of age	4,009	8%
No diagnosis of epilepsy or epilepsy-like conditions in the 12-month post-index period	14,305	30%
A diagnosis of anoxic brain injury, coma, unspecified cerebrovascular disease or unspecified conduction disorder  in the 6-month pre-index period	648	1%
Presence of non-relevant CPT codes during index VEEG	13,603	28%
Length of stay/study greater than 7 days	3,668	8%
No continuous enrollment in the 6 months preceding index VEEG	7,142	15%
No continuous enrollment in the 12 months following index VEEG	19,054	40%
No eligibility data	675	1%
Both places of service for index VEEG	112	0%
Final patient sample	13,958	29%
Inpatient VEEG	5,271	38%
Outpatient VEEG	8,687	62%

Abbreviations. CPT, Current Procedural Terminology; EEG, electroencephalography; VEEG, video electroencephalography.

Table 2. Demographic and baseline clinical characteristics.

	All patients		Inpatient VEEG		Outpatient VEEG		Standardized difference	p-value
	n	%	n	%	n	%
Total patients	13,958	100.0%	5,271	100.0%	8,687	100.0%
Demographics
Age (mean, SD)	29.9	21.1	28.7	19.5	30.7	22.0	0.093	<0.0001
Age category
3–9 years	2,392	17.1%	899	17.1%	1,493	17.2%	0.242	<0.0001
10–17 years	3,193	22.9%	1,100	20.9%	2,093	24.1%
18–34 years	3,073	22.0%	1,379	26.2%	1,694	19.5%
35–49 years	2,147	15.4%	882	16.7%	1,265	14.6%
50–64 years	2,236	16.0%	804	15.3%	1,432	16.5%
65–84 years	838	6.0%	188	3.6%	650	7.5%
85+ years	79	0.6%	19	0.4%	60	0.7%
Gender
Male	5,878	42.1%	2,188	41.5%	3,690	42.5%	−0.020	0.2619
Female	8,080	57.9%	3,083	58.5%	4,997	57.5%
Payer type
Commercial	12,974	93.0%	5,040	95.6%	7,934	91.3%	0.174	<0.0001
Medicare	984	7.0%	231	4.4%	753	8.7%
Geographic region of practice
Northeast	3,323	23.8%	1,257	23.8%	2,066	23.8%	0.207	<0.0001
Midwest	3,234	23.2%	1,226	23.3%	2,008	23.1%
South	5,854	41.9%	2,001	38.0%	3,853	44.4%
West	1,421	10.2%	728	13.8%	693	8.0%
Unknown	126	0.9%	59	1.1%	67	0.8%
Index year
2013	2,894	20.7%	1,311	24.9%	1,583	18.2%	0.185	<0.0001
2014	3,722	26.7%	1,434	27.2%	2,288	26.3%
2015	3,795	27.2%	1,359	25.8%	2,436	28.0%
2016	3,547	25.4%	1,167	22.1%	2,380	27.4%
Length of service for index VEEG (mean, SD)	1.5	1.6	2.7	1.6	0.8	1.0	−1.390	<0.0001
LOS category
Less than 1 full day	4,865	34.9%	227	4.3%	4,638	53.4%	1.623	<0.0001
1 day	2,731	19.6%	1,124	21.3%	1,607	18.5%
2 days	3,356	24.0%	1,316	25.0%	2,040	23.5%
3 days	1,298	9.3%	1,047	19.9%	251	2.9%
4 days	922	6.6%	823	15.6%	99	1.1%
5 or more days	786	5.6%	734	13.9%	52	0.6%
Clinical and disease characteristics
Deyo Charlson Comorbidity Index (mean, SD)	0.6	1.2	0.6	1.1	0.7	1.3	0.088	<0.0001
Number of DCCI conditions
None	9,525	68.2%	3,723	70.6%	5,802	66.8%	0.100	<0.0001
1	2,110	15.1%	735	13.9%	1,375	15.8%
2	1,248	8.9%	473	9.0%	775	8.9%
3 or more	1,075	7.7%	340	6.5%	735	8.5%
Psychiatric comorbidities	3,795	27.2%	1,485	28.2%	2,310	26.6%	−0.036	0.0418
Major depressive disorder	1,150	8.2%	451	8.6%	699	8.0%	−0.019	0.2883
Other depression	919	6.6%	412	7.8%	507	5.8%	−0.079	<0.0001
Bipolar disorder	391	2.8%	143	2.7%	248	2.9%	0.009	0.6224
Anxiety	2,525	18.1%	998	18.9%	1,527	17.6%	−0.035	0.0437
Schizophrenia	59	0.4%	29	0.6%	30	0.3%	−0.031	0.0706
Insomnia	616	4.4%	213	4.0%	403	4.6%	0.029	0.0953

Table 3. Post-index epilepsy-related healthcare costs for VEEG patients, by cohort.

Time period and visit category	All VEEG patients (n = 13,958)		Inpatient VEEG (n = 5,271)		Outpatient VEEG (n = 8,687)		P-value
	Mean	SD	Mean	SD	Mean	SD
1 Month
Total epilepsy-related costs	$1,256	$13,502	$1,805	$20,947	$922	$5,140	<0.0001
Medical	$996	$13,460	$1,410	$20,905	$746	$5,080	0.2595
Inpatient	$428	$13,158	$757	$20,526	$228	$4,739	0.0020
ER	$62	$579	$73	$625	$55	$549	0.0014
Ambulance	$23	$425	$26	$229	$21	$508	0.0003
Radiology	$97	$570	$121	$682	$83	$489	0.4706
Physician office	$152	$688	$106	$398	$180	$814	<0.0001
Other outpatient	$235	$1,953	$327	$2,912	$180	$987	<0.0001
Pharmacy	$259	$920	$396	$1,193	$176	$693	<0.0001
3 Months
Total epilepsy-related costs	$3,344	$17,018	$5,145	$25,666	$2,251	$7,908	<0.0001
Medical	$2,575	$16,689	$3,991	$25,288	$1,716	$7,588	<0.0001
Inpatient	$1,235	$15,637	$2,201	$23,999	$649	$6,523	<0.0001
ER	$158	$933	$195	$1,022	$135	$874	<0.0001
Ambulance	$56	$591	$75	$659	$44	$545	<0.0001
Radiology	$177	$790	$259	$1,027	$128	$596	<0.0001
Physician office	$317	$1,074	$290	$763	$333	$1,225	0.0143
Other outpatient	$633	$4,087	$972	$5,506	$428	$2,886	<0.0001
Pharmacy	$769	$2,389	$1,154	$3,091	$535	$1,798	<0.0001
6 Months
Total epilepsy-related costs	$6,471	$24,409	$10,546	$35,142	$3,998	$13,851	<0.0001
Medical	$4,912	$23,350	$8,198	$33,877	$2,919	$13,010	<0.0001
Inpatient	$2,654	$21,203	$5,070	$31,125	$1,188	$11,354	<0.0001
ER	$287	$1,311	$363	$1,529	$241	$1,157	<0.0001
Ambulance	$113	$1,121	$151	$1,367	$90	$941	<0.0001
Radiology	$239	$948	$358	$1,246	$167	$699	<0.0001
Physician office	$510	$1,490	$507	$1,141	$513	$1,667	<0.0001
Other outpatient	$1,110	$6,103	$1,750	$8,077	$722	$4,457	<0.0001
Pharmacy	$1,558	$4,847	$2,348	$6,368	$1,079	$3,542	<0.0001
9 Months
Total epilepsy-related costs	$9,146	$29,527	$15,076	$42,362	$5,548	$16,669	<0.0001
Medical	$6,779	$27,570	$11,508	$40,064	$3,911	$15,023	<0.0001
Inpatient	$3,821	$24,648	$7,480	$36,445	$1,601	$12,540	<0.0001
ER	$408	$1,729	$516	$2,054	$342	$1,494	<0.0001
Ambulance	$153	$1,239	$210	$1,502	$118	$1,047	<0.0001
Radiology	$291	$1,081	$435	$1,413	$204	$803	<0.0001
Physician office	$680	$1,863	$670	$1,305	$687	$2,131	<0.0001
Other outpatient	$1,427	$7,182	$2,198	$9,065	$960	$5,696	<0.0001
Pharmacy	$2,367	$7,369	$3,568	$9,667	$1,637	$5,400	<0.0001
12 Months
Total epilepsy-related costs	$11,889	$34,403	$19,332	$48,012	$7,372	$21,195	<0.0001
Medical	$8,654	$31,263	$14,444	$44,205	$5,142	$18,767	<0.0001
Inpatient	$4,876	$27,467	$9,361	$39,828	$2,154	$15,174	<0.0001
ER	$538	$2,160	$695	$2,622	$443	$1,817	<0.0001
Ambulance	$195	$1,404	$268	$1,657	$151	$1,223	<0.0001
Radiology	$342	$1,214	$512	$1,577	$239	$911	<0.0001
Physician office	$866	$2,303	$832	$1,512	$886	$2,672	<0.0001
Other outpatient	$1,838	$8,871	$2,776	$10,481	$1,269	$7,677	<0.0001
Pharmacy	$3,234	$10,049	$4,888	$13,217	$2,231	$7,322	<0.0001

The cohorts were mutually exclusive, and were based on site of service for the index VEEG.

Table 4. Index all-cause and epilepsy-related adjusted costs.

Index costs^a	Inpatient		Outpatient
	Mean	95% CI	Mean	95% CI
Total all-cause costs	$15,312	$14,613–$16,045	$4,435	$4,243–$4,636
Total epilepsy-related costs	$13,821	$12,844–$14,873	$4,098	$3,824–$4,391

^aA generalized linear model with a gamma distribution and a log link function was used to estimate all-cause and epilepsy-related costs associated with the index VEEG service, while controlling for baseline demographic and clinical characteristics.

Table 5. Post-index (12-month) all-cause and epilepsy-related adjusted costs.

Post-index costs^a	Inpatient		Outpatient
	Mean	95% CI	Mean	95% CI
Total all-cause costs	$39,203	$36,666–$41,916	$25,824	$24,264–$27,484
Total epilepsy-related costs	$12,733	$11,693–$13,865	$6,114	$5,648–$6,619

^aA generalized linear model with a gamma distribution and a log link function was used to estimate all-cause and epilepsy-related costs in the 12-month post-index period, while controlling for baseline demographic and clinical characteristics.

Figure 1. Kaplan-Meier curve for post-index diagnostic procedure. Post-index diagnostic testing was defined as any additional procedure in the 12 months following the index VEEG. (1) Inpatient or outpatient VEEG (CPT: 95951). (2) Long-term EEG (CPT: 95827, 95950, 95953, 95956). (3) Routine EEG (CPT: 95812, 95813, 95816, 95819, 95822). (4) Brain CT/MRI scan (CPT: 78608, 70450, 70460, 70470, 70551, 70552, 70553). Abbreviations. CPT, Current Procedural Terminology; CT, computed tomography; EEG, electroencephalography; MRI, magnetic resonance imaging; VEEG, video electroencephalography.

Table 6. Clinical outcomes in VEEG patients, by cohort.

Clinical outcomes	All VEEG patients (n = 13,958)			Inpatient VEEG (n = 5,271)			Outpatient VEEG (n = 8,687)			p-value
	No. of patients	%		No. of patients	%		No. of patients	%
Time to index VEEG (days)
mean (SD)	35.8	37.5		43.5	39.1		31.1	35.7		<0.0001
median (IQR)	23.0	(9, 48)		33.0	(14, 61)		19.0	(7, 40)
Post-index diagnostic testing	6,522	46.7%		2,687	51.0%		3,835	44.1%		<0.0001
Inpatient	961	14.7%		504	18.8%		457	11.9%		<0.0001
Outpatient	5,561	85.3%		2,183	81.2%		3,378	88.1%
Days to diagnostic test
Mean (SD)	120.1	112.0		115.9	109.4		123.0	113.7		0.0123
Median (IQR)	86.0	(19–205)		83.0	(18–193)		88.0	(19–214)
Procedure
VEEG	1,794	27.5%	100.0%	818	30.4%	100.0%	976	25.4%	100.0%	<0.0001
Inpatient	608	9.3%	33.9%	338	12.6%	41.3%	270	7.0%	27.7%	<0.0001
Outpatient	1,186	18.2%	66.1%	480	17.9%	58.7%	706	18.4%	72.3%
Long-term EEG	477	7.3%	100.0%	181	6.7%	100.0%	296	7.7%	100.0%	0.1337
Inpatient	4	0.1%	0.8%	2	0.1%	1.1%	2	0.1%	0.7%	0.6364
Outpatient	473	7.3%	99.2%	179	6.7%	98.9%	294	7.7%	99.3%
EEG	1,525	23.4%	100.0%	575	21.4%	100.0%	950	24.8%	100.0%	0.0015
Inpatient	108	1.7%	7.1%	51	1.9%	8.9%	57	1.5%	6.0%	0.0342
Outpatient	1,417	21.7%	92.9%	524	19.5%	91.1%	893	23.3%	94.0%
MRI	1,174	18.0%	100.0%	430	16.0%	100.0%	744	19.4%	100.0%	0.0004
Inpatient	56	0.9%	4.8%	30	1.1%	7.0%	26	0.7%	3.5%	0.0070
Outpatient	1,118	17.1%	95.2%	400	14.9%	93.0%	718	18.7%	96.5%
CT	1,945	29.8%	100.0%	896	33.3%	100.0%	1,049	27.4%	100.0%	<0.0001
Inpatient	276	4.2%	14.2%	134	5.0%	15.0%	142	3.7%	13.5%	0.3715
Outpatient	1,669	25.6%	85.8%	762	28.4%	85.0%	907	23.7%	86.5%

The cohorts were mutually exclusive, and were based on site of service for the index VEEG.

Table 7. Adjusted clinical time outcomes.

Clinical outcomes^a	Inpatient		Outpatient
	Mean	95% CI	Mean	95% CI
Pre-index time to index VEEG(in days)	42.5	40.0–45.1	30.6	28.9–32.3
Post-index time to diagnostic testing(in days)	122.2	110.4–135.1	129.4	117.7–142.4

^aA generalized linear model with a negative binomial distribution and a log link function was used to estimate time to index VEEG and time to post-index diagnostic testing, while controlling for baseline demographic and clinical characteristics.

Table 8. Cox proportional hazards model for post-index diagnostic procedure.

Demographic and clinical characteristics	Parameter estimate	Standard error	p-value	Hazard ratio	95% CI
					Lower	Upper
VEEG cohort
Outpatient	−0.1837	0.0258	<0.0001	0.832	0.791	0.875
Age (in years)	−0.0007	0.0008	0.3597	0.999	0.998	1.001
Gender
Female	−0.0024	0.0255	0.9255	0.998	0.949	1.049
Plan type
Medicare	0.0764	0.0588	0.1937	1.079	0.962	1.211
Geographic region
Midwest	−0.0860	0.0360	0.0169	0.918	0.855	0.985
South	−0.1225	0.0318	0.0001	0.885	0.831	0.942
West	−0.1263	0.0469	0.0071	0.881	0.804	0.966
Unknown	0.0079	0.1282	0.9511	1.008	0.784	1.296
Index year
2014	−0.0526	0.0361	0.1454	0.949	0.884	1.018
2015	−0.1190	0.0364	0.0011	0.888	0.827	0.953
2016	−0.0601	0.0368	0.1025	0.942	0.876	1.012
Number of DCCI conditions
One	0.1024	0.0364	0.0049	1.108	1.032	1.19
Two	0.1417	0.0439	0.0012	1.152	1.057	1.256
Three or more	0.3289	0.0477	<0.0001	1.389	1.266	1.525
Presence of a psychiatric comorbidity	0.1000	0.0286	0.0005	1.105	1.045	1.169
Pre-index epilepsy-related inpatient visit	0.2388	0.0504	<0.0001	1.270	1.150	1.402
Pre-index epilepsy-related routine EEG	0.0149	0.0274	0.5865	1.015	0.962	1.071
Pre-index epilepsy-related ER visit	0.1369	0.0338	<0.0001	1.147	1.073	1.225
Pre-index epilepsy-related ambulance use	−0.0076	0.0407	0.8523	0.992	0.916	1.075
Pre-index epilepsy-related radiology visit	−0.0860	0.0309	0.0054	0.918	0.864	0.975
Pre-index epilepsy-related pharmacy visit	0.1253	0.0267	<0.0001	1.133	1.076	1.194
Pre-index epilepsy-related total costs (in thousands)	0.0014	0.0004	0.0008	1.001	1.001	1.002

Table 9. Clinical outcomes in VEEG patients, pre- and post-VEEG diagnoses.

Clinical outcomes	All VEEG patients		Inpatient VEEG		Outpatient VEEG		p-value
	(n = 13,958)		(n = 5,271)		(n = 8,687)
	No. of patients	%	No. of patients	%	No. of patients	%
Pre-index diagnosis
Abnormal involuntary movements	248	1.8%	65	1.2%	183	2.1%	<0.0001
Altered mental status	181	1.3%	53	1.0%	128	1.5%
Conversion disorder	31	0.2%	16	0.3%	15	0.2%
Dizziness and giddiness	357	2.6%	60	1.1%	297	3.4%
Epilepsy	5,968	42.8%	2,696	51.1%	3,272	37.7%
Other and unspecified convulsions	3,381	24.2%	1,251	23.7%	2,130	24.5%
Other and unspecified encephalopathy	224	1.6%	55	1.0%	169	1.9%
Post-traumatic seizures	7	0.1%	4	0.1%	3	0.0%
Stupor and somnolence	94	0.7%	25	0.5%	69	0.8%
Syncope and collapse	822	5.9%	165	3.1%	657	7.6%
Transient alteration of awareness	318	2.3%	92	1.7%	226	2.6%
Unclear/multiple diagnosis	964	6.9%	402	7.6%	562	6.5%
Index diagnosis
Abnormal involuntary movements	261	1.9%	82	1.6%	179	2.1%	<0.0001
Altered mental status	194	1.4%	44	0.8%	150	1.7%
Anoxic brain damage	9	0.1%	3	0.1%	6	0.1%
Coma	3	0.0%	0	0.0%	3	0.0%
Conversion disorder	146	1.0%	99	1.9%	47	0.5%
Dizziness and giddiness	549	3.9%	113	2.1%	436	5.0%
Epilepsy	6,761	48.4%	2,970	56.3%	3,791	43.6%
Other and unspecified convulsions	3,458	24.8%	1,155	21.9%	2,303	26.5%
Other and unspecified encephalopathy	288	2.1%	67	1.3%	221	2.5%
Post-traumatic seizures	11	0.1%	2	0.0%	9	0.1%
Stupor and somnolence	78	0.6%	22	0.4%	56	0.6%
Syncope and collapse	1,012	7.3%	248	4.7%	764	8.8%
Transient alteration of awareness	326	2.3%	77	1.5%	249	2.9%
Unclear/multiple diagnosis	842	6.0%	385	7.3%	457	5.3%
Unspecified cerebrovascular disease	16	0.1%	4	0.1%	12	0.1%
Unspecified conduction disorder	4	0.0%	0	0.0%	4	0.0%
Patients with pre-index epilepsy-related diagnosis	12,595	90.2%	4,884	92.7%	7,711	88.8%	<0.0001
Change in diagnosis after VEEG procedure
Same diagnosis	7,373	52.8%	2,755	52.3%	4,618	53.2%	<0.0001
Diagnosis changed	3,951	28.3%	1,589	30.1%	2,362	27.2%
Less refined diagnosis	557	4.0%	256	4.9%	301	3.5%
More refined diagnosis	714	5.1%	284	5.4%	430	4.9%
New diagnosis (no pre-index diagnosis)	1,363	9.8%	387	7.3%	976	11.2%

The cohorts were mutually exclusive, and were based on site of service for the index VEEG.