Cost and clinical consequences of stress/single-photon emission computed tomography testing with specific medications

Figures & data

Table 1.  Codes used to identify ST, SPECT, adenosine and dipyridamole.

Procedure/ drug	Code type	Codes
Planar	CPT	78460, 78461
SPECT	CPT	78464, 78465, 78478, 78480
Stress test	ICD-9 procedure CPT Revenue code	89.44 93015, 93016, 93017, 93018 0482
Adenoscan*	NDC CPT/HCPC	10019006302, 10019006303 17478054202, 00469087120 00469087130, 54868582500 54868582501, 55390006710 55390006801, 63323065102 63323065104, 00703877103 00703877301 J0152
Dipyridamole	NDC† CPT/HCPC	55390055501, 55390055510 55390055590, 59911706902 60505071500, 60505071501 63323061302, 63323061310 00641256941, 00641256944 00703165201, 00703165202 00703165401, 00703165402 J1245

Table 2.  Summary statistics of baseline characteristics.

Demographic factors	Dipyridamole		Adenosine		p-value	SD difference
	n = 12,351		n = 59,969
	Mean/n	SD/%	Mean/n	SD/%
Male	6,219	50.35%	31,619	52.73%	<0.0001	4.7502
Age group, years
18–39	255	2.06%	1,168	1.95%	0.3942	0.8340
40–64	7,275	58.90%	37,011	61.72%	<0.0001	5.7554
65+	4,821	39.03%	21,790	36.34%	<0.0001	5.5692
US region
Northeast	1,928	15.61%	3,000	5.00%	<0.0001	35.4304
North Central	1,298	10.51%	14,363	23.95%	<0.0001	36.1699
South	7,046	57.05%	35,119	58.56%	0.0019	3.0657
West	2,079	16.83%	7,487	12.48%	<0.0001	12.3157
Clinical factors at baseline
Deyo–Charlson Comorbidity Index	1.39	1.72	1.34	1.68	0.0019	3.0892
Elixhauser Index >2	3,785	30.65%	17,459	29.11%	0.0007	3.3472
Average # of office visits	0.1756943	0.3805753	0.1751738	0.3801189	0.8898	0.1368

Table 3.  Summary statistics of baseline characteristics after propensity score matching.

Demographic factors	Dipyridamole		Adenosine		p-value	SD difference
	n = 12,220		n = 12,220
	Mean/n	SD/%	Mean/n	SD/%
Male	6143	50.27%	6128	50.15%	0.8005	0.2455
Age group, years
18–39	251	2.05%	255	2.09%	0.8517	0.2299
40–64	7209	58.99%	7151	58.52%	0.4273	0.9641
65+	4760	38.95%	4814	39.39%	0.4609	0.9052
US region
Northeast	1877	15.36%	1877	15.36%	1.0000	0.0000
North Central	1286	10.52%	1287	10.53%	0.5637	0.0267
South	6994	57.23%	6996	57.25%	0.8937	0.0331
West	2063	16.88%	2060	16.86%	0.8401	0.0656
Clinical factors at baseline
Deyo–Charlson Comorbidity Index	1.39	1.72	1.39	1.70	0.9484	0.1245
Elixhauser Index >2	3759	30.76%	3810	31.18%	0.4537	0.9026
Number of unique medication	9.05	6.40	9.13	6.57	0.6335	1.1830
Average # of office visits	0.1754501	0.3803672	0.1786416	0.3830676	0.5134	0.8361

Table 4.  Risk adjusted outcomes measures for the same day of ST/SPECT testing.

	Dipyridamole		Adenosine		p-value	SD difference
	n = 12,220		n = 12,220
	Mean/n	SD/%	Mean/n	SD/%
Test-related complications
ER visits	80	0.65%	28	0.23%	<0.0001	6.4186
IP events	4	0.03%	3	0.02%	0.7055	0.4836
Sinoatrial blocks	19	0.16%	31	0.25%	0.0897	2.1733
Atrioventricular nodes blocks	1	0.01%	2	0.02%	0.5637	0.7386
Other arrhythmias	121	0.99%	112	0.92%	0.5520	0.7579
Myocardial infarction	25	0.20%	37	0.30%	0.1275	1.9522
Bronchospasm	0	0.00%	0	0.00%		0.0000
Stroke	8	0.07%	11	0.09%	0.4913	0.8808
Hypotension	1	0.01%	1	0.01%	1.0000	0.0000
Respiratory distress	0	0.00%	0	0.00%		0.0000
Aminophylline administration	0	0.00%	0	0.00%		0.0000
Test-related symptoms
Headache	7	0.06%	5	0.04%	0.5637	0.7388
Dizziness	37	0.30%	42	0.34%	0.5737	0.7208
Shortness of breath	686	5.61%	788	6.45%	0.0056	3.5066
Angina pectoris	869	7.11%	734	6.01%	0.0004	4.4634
Atypical chest pain	555	4.54%	574	4.70%	0.5586	0.7407
Test-related healthcare costs (only patients who have costs)
Inpatient hospital costs	$6934	$6,898	$4,260	$2897	0.6875	50.1370
Office visit costs	$1096	$713	$1,240	$750	<0.0001	19.7637
Outpatient hospital costs	$1271	$1,557	$1,320	$1695	0.0124	3.0510
ER costs	$1276	$1,733	$1,095	$1092	<0.0001	12.5176
Other utilizations	$181	$302	$469	$2357	0.0046	17.1407
Medical costs	$1163	$896	$1,265	$987	0.0004	10.8887
Test-related healthcare costs (all patients)
Inpatient hospital costs	$2	$165	$1	$76	0.6875	0.9452
Office visit costs	$189	$509	$219	$568	<0.0001	5.4800
Outpatient hospital costs	$12	$191	$8	$163	0.0124	2.1827
ER costs	$8	$172	$3	$73	<0.0001	4.3391
Other utilizations	$2	$38	$4	$207	0.0046	0.9767
Medical costs	$213	$592	$234	$649	0.0004	3.2535