Initiation And Persistence With Antiplatelet Agents Among The Patients With Acute Coronary Syndromes: A Retrospective, Observational Database Study In China

Figures & data

Figure 1 Flow chart of sample selection.

Table 1 Baseline Characteristics

Demographic Characteristics	N=21,450
Age, Mean (SD)	64.6	10.7
Age group, n (%)
≤54	3,584	16.7%
55–64	7,670	35.8%
65–74	5,731	26.7%
≥75	4,465	20.8%
Female, n (%)	9,861	46.0%
Retired, n (%)	17,275	80.5%
Charlson Comorbidity Index, Mean (SD)	1.7	1.6
Medical history, n (%)
Hypertension	16,090	75.0%
Hyperlipidemia	10,006	46.6%
Diabetes mellitus	8,038	37.5%
Prior stroke	5,586	26.0%
Prior angina	5,388	25.1%
Prior myocardial infraction	3,270	15.2%
Prior percutaneous coronary intervention (PCI)	1,418	6.6%
Prior use,^a n (%)
Antiplatelet	11,728	54.7%
β-blockers	8,801	41.0%
Calcium channel blockers	12,010	56.0%
Antiplatelet agents, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers	11,446	53.4%
Statins	9,347	43.6%
Resource utilization and cost
Any hospitalizations, n (%)	6,668	31.1%
Number of outpatient visits among all patients, Mean (SD)	30.5	31.7
Total direct medical cost (CNY), Mean (SD)	12,772	18,893
Index hospitalization
Any PCI, n (%)	4,771	22.2%
Mean length of stay (days), Mean (SD)	10.5	5.5

Note: ^aHad at least one prescription during the baseline

Table 2 Initiation with Antiplatelet Therapy Within the 30 Days After Discharge

	N=21,450
Initiation with antiplatelet therapy, n (%)	15,071	70.3%
Aspirin	10,160	47.4%
Clopidogrel	10,226	47.7%
Dual therapy	5,336	24.9%
Initiation without antiplatelet therapy, n (%)	6379	29.7%

Table 3 Unadjusted And Adjusted Characteristics For Patients Initiated With And Without Antiplatelet Agents (N=21,450)

Patient Characteristics	Initiation With Antiplatelet (N=15,071)		Initiation Without Antiplatelet (N=6,379)		P-value	Adjusted Analysis
	N	%	N	%		OR	95% CI		P-value
Age group (vs ≤54)
≤54	2,267	15.0%	1,317	20.6%	<0.001	1 (reference)
55–64	5,449	36.2%	2,221	34.8%	0.062	1.46	1.31	1.63	<0.001
65–74	4,253	28.2%	1,478	23.2%	<0.001	1.82	1.61	2.07	<0.001
≥75	3,102	20.6%	1,363	21.4%	0.019	1.70	1.49	1.93	<0.001
Female (vs male)	6,356	42.2%	3,505	54.9%	<0.001	0.75	0.70	0.81	<0.001
Retired (vs Working)	12,130	80.5%	5,145	80.7%	0.774	0.97	0.87	1.09	0.646
Charlson Comorbidity Index	1.8	0.0	1.6	0.0	<0.001	1.04	1.00	1.07	0.032
Medical history (Yes vs No)
Hypertension	11,475	76.1%	4,615	72.3%	<0.001	0.99	0.88	1.10	0.804
Hyperlipidemia	7,266	48.2%	2,740	43.0%	<0.001	1.00	0.92	1.08	0.949
Diabetes mellitus	5,867	38.9%	2,171	34.0%	<0.001	0.96	0.89	1.05	0.363
Prior stroke	3,958	26.3%	1,628	25.5%	0.258	0.98	0.90	1.07	0.700
Prior angina	3,779	25.1%	1,609	25.2%	0.818	0.94	0.87	1.03	0.180
Prior myocardial infraction	2,420	16.1%	850	13.3%	<0.001	1.18	1.07	1.30	0.001
Prior percutaneous coronary intervention (PCI)	1,182	7.8%	236	3.7%	<0.001	1.47	1.26	1.73	<0.001
Prior use (Yes vs No)
Antiplatelet	8,970	59.5%	2,758	43.2%	<0.001	1.93	1.78	2.09	<0.001
β-blockers	6,493	43.1%	2,308	36.2%	<0.001	1.13	1.05	1.22	0.001
Calcium channel blockers	8,579	56.9%	3,431	53.8%	<0.001	0.95	0.87	1.03	0.214
Antiplatelet agents, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers	8,188	54.3%	3,258	51.1%	<0.001	0.98	0.90	1.06	0.599
Statins	6,833	45.3%	2,514	39.4%	<0.001	0.97	0.88	1.06	0.447
Any baseline inpatient visits (yes vs no)	4,405	29.2%	2,263	35.5%	<0.001	0.60	0.55	0.66	<0.001
Number of baseline outpatient visits	32.6	33.4	25.5	26.8	<0.001	1.01	1.00	1.01	<0.001
Total baseline all-cause direct medical cost	13,370.1	19,958.4	11,358.0	16,012.1	<0.001	1.00	0.98	1.02	0.903
Index PCI (Yes vs No)	4,648	30.8%	123	1.9%	<0.001	22.40	18.63	26.92	<0.001
Length of stay during the index event	10.2	0.0	11.3	0.1	<0.001	0.97	0.97	0.98	<0.001

Figure 2 Persistence with antiplatelet agents during the follow-up period.

Table 4 Unadjusted and Adjusted Characteristics for Patients Who Were Persistent and Non-Persistent Antiplatelet Agents (N=15,071)

Patient Characteristics	Persistent (N=2,262)		Non-Persistent (N=12,809)		P-value	Adjusted Analysis
	N	%	N	%		HR	95% CI		P-value
Age group (vs ≤54)
≤54	345	15.3%	1,922	15.0%	0.762	1 (reference)
55–64	885	39.1%	4,564	35.6%	0.001	0.96	0.90	1.02	0.179
65–74	626	27.7%	3,627	28.3%	0.532	0.98	0.91	1.05	0.548
≥75	406	17.9%	2,696	21.0%	0.001	1.08	1.00	1.17	0.044
Female (vs male)	782	34.6%	5,574	43.5%	<0.001	1.22	1.18	1.27	<0.001
Retired (vs Working)	1,782	78.8%	10,348	80.8%	0.026	1.05	0.99	1.12	0.129
Charlson Comorbidity Index	2.6	0.0	1.7	0.0	<0.001	0.99	0.97	1.00	0.145
Medical history (Yes vs No)
Hypertension	1,794	79.3%	9,681	75.6%	<0.001	1.10	1.03	1.17	0.003
Hyperlipidemia	1,229	54.3%	6,037	47.1%	<0.001	1.06	1.01	1.11	0.010
Diabetes mellitus	1,276	56.4%	4,591	35.8%	<0.001	0.96	0.91	1.00	0.068
Prior stroke	793	35.1%	3,165	24.7%	<0.001	1.02	0.97	1.07	0.523
Prior angina	650	28.7%	3,129	24.4%	<0.001	1.01	0.96	1.05	0.731
Prior myocardial infraction	396	17.5%	2,024	15.8%	0.042	1.05	1.00	1.11	0.064
Prior  percutaneous coronary intervention (PCI)	239	10.6%	943	7.4%	<0.001	0.91	0.84	0.97	0.007
Prior use (Yes vs No)
Antiplatelet	1,675	74.0%	7,295	57.0%	<0.001	0.78	0.74	0.81	<0.001
β-blockers	1,009	44.6%	5,484	42.8%	0.112	1.05	1.01	1.10	0.011
Calcium channel blockers	1,391	61.5%	7,188	56.1%	<0.001	1.08	1.03	1.13	0.001
Antiplatelet agents, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers	1,377	60.9%	6,811	53.2%	<0.001	0.98	0.94	1.03	0.391
Statins	1,254	55.4%	5,579	43.6%	<0.001	0.91	0.87	0.96	<0.001
Any baseline inpatient visits (yes vs no)	818	36.2%	3,587	28.0%	<0.001	0.95	0.90	1.00	0.035
Number of baseline outpatient visits	54.9	52.2	28.6	27.0	<0.001	0.99	0.99	0.99	<0.001
Total baseline all-cause direct medical cost	22,445.4	25,437.9	11,767.5	18,367.0	<0.001	1.04	1.03	1.05	<0.001
Index PCI (Yes vs No)	979	43.3%	3,669	28.6%	<0.001	0.51	0.49	0.53	<0.001
Length of stay during the index event	10.9	0.1	10.1	0.0	<0.001	0.99	0.99	1.00	<0.001