Analysis of Adherence to Antihypertensive Drugs in Chinese Patients with Hypertension: A Retrospective Analysis Using the China Health Insurance Association Database 

Figures & data

Figure 1 Study flow diagram.

Table 1 Baseline and Comorbidity Characteristics of Different Antihypertensive Drugs

	Benazepril	Nifedipine GITs	Amlodipine	Metoprolol	Valsartan	Indapamide	Valsartan/Amlodipine
No. of patients (N)	3778	11,077	21,945	16,170	8910	1661	1035
Primary diagnosis with HTN (% of n)
Patients with primary HTN	96.48	97.73	97.02	96.56	97.03	96.63	95.46
Patients with secondary HTN	1.11	0.48	2.09	2.12	1.54	1.51	3.48
Secondary diagnosis with HTN (% of N)	2.41	1.79	0.89	1.32	1.43	1.86	1.06
Mean observation duration (days)	291.56	295.45	290.55	293.65	291.38	293.65	289.25
Men (% of N)	55.11	50.75	49.45	50.96	50.62	52.68	52.56
Women (% of N)	44.89	49.25	50.55	49.04	49.38	47.32	47.44
Mean age (years)	63.12	63.08	63.80	64.85	62.44	64.21	62.29
*Comorbidities (% of N)	66.91	76.14	53.09	64.85	63.45	56.35	60.29
Coronary heart disease	48.91	60.96	35.77	52.58	45.44	40.28	39.23
Diabetes mellitus	39.89	43.83	27.86	28.67	35.16	31.13	32.75
Stroke	13.76	17.58	10.76	11.68	11.95	12.52	11.79
Chronic renal diseases	3.26	3.85	2.24	2.54	3.31	1.69	4.35
Peripheral vascular disease	0.82	1.27	0.52	0.72	0.79	0.66	0.97

Note: *Some patients have more than one comorbidity.

Abbreviations: HTN, hypertension; GITs, gastrointestinal tablets.

Figure 2 MPR of different AHT drugs. (A) Mean MPR values; (B) percentage of population with MPR of ≥0.5; (C) population distribution among different range of MPR of AHT drugs. The difference among groups was statistically significant for mean MPR and proportion of patients with ≥0.5 MPR (P<0.0001 for both).

Abbreviations: MPR, medicine possession ratio; GITs, gastrointestinal tablets.

Table 2 The Use of the Seven Antihypertensive Drugs Among the Patients

Variables	Benazepril N=3778	Nifedipine GITs N=11,077	Amlodipine N=21,945	Metoprolol N=16,170	Valsartan N=8910	Indapamide N=1661	Valsartan/amlodipine N=1035
Proportion of multidrug combination in the first prescription (%)	61.83	46.06	51.52	68.92	57.12	68.27	40.19
Proportion of drug replacement (%)	62.07	61.94	51.29	63.52	61.28	77.54	48.41
Switching to benazepril (%)	–	3.77	2.21	2.03	1.76	1.93	0.77
Switching to nifedipine controlled release tablets (%)	9.95	–	3.80	6.64	9.58	6.26	2.51
Switching to amlodipine (%)	11.91	7.39	–	11.21	12.29	10.05	10.63
Switching to metoprolol (%)	9.56	8.87	8.28	–	8.73	9.39	9.47
Switching to valsartan (%)	5.11	8.01	5.12	5.05	–	5.54	8.70
Switching to indapamide (%)	1.48	1.27	0.87	1.06	0–.94	–	1.06
Switching to valsartan/amlodipine (%)	0.00	0.50	0.76	0.76	1.04	0.84	–
Switching to antihypertensive drug(s) other than the seven target drugs (%)	37.53	42.13	38.61	46.00	38.87	43.53	30.14
Daily cost of antihypertensive drugs (yuan) (%)	7.81	4.49	4.38	4.00	4.40	0.93	8.70

Abbreviation: GITs, gastrointestinal tablets.

Table 3 Hospital Visits by Patients Receiving Studied AHT Drugs

	Benazepril	Nifedipine GITs	Amlodipine	Metoprolol	Valsartan	Indapamide	Valsartan/amlodipine
Annual per capita outpatient visit (mean)	27.21	32.60	22.11	24.79	27.38	25.04	19.73
Annual per capita hospital admission (mean)	0.49	0.39	0.38	0.55	0.37	0.48	0.32
Direction of outpatient flow (%)
Tier 3 hospitals	31.96	31.03	32.24	36.08	32.71	29.38	57.32
Tier 2 hospitals	16.80	15.34	15.73	18.05	15.52	19.20	15.43
Tier 1 hospitals	48.26	50.96	49.59	42.57	49.36	48.32	26.11
Pharmacies	2.88	2.53	2.26	3.06	2.30	2.92	1.11
Others	0.10	0.14	0.18	0.23	0.11	0.18	0.03
Direction of inpatient flow (%)
Tier 3 hospitals	54.04	59.97	56.10	56.68	58.56	50.25	77.98
Tier 2 hospitals	27.08	25.68	28.83	32.31	26.22	32.13	15.90
Tier 1 hospitals	18.18	13.94	13.44	9.79	13.60	15.88	5.50
Others	0.71	0.41	1.63	1.22	1.62	1.75	0.61

Abbreviation: GITs, gastrointestinal tablets.

Table 4 Factors Affecting MPR. Results of Multivariate Regression Analysis

Variables	Parameter estimation	Standard error	T value	P-value
Gender (male patients as control)	−0.0046	0.0024	−1.9	0.0573
Age (≤40 years as control)
41–60 years	0.0776	0.0068	11.44	<0.0001
61–80 years	0.0999	0.0068	14.73	<0.0001
≥81 years	0.0912	0.0078	11.75	<0.0001
City level (prefecture level as control)
Municipalities	0.0746	0.0042	17.72	<0.0001
Provincial capital	0.0040	0.0043	0.93	0.3516
Comorbidities
Diabetes	0.0330	0.0027	12.18	<0.0001
Stroke	0.0112	0.0038	2.92	0.0035
Coronary artery disease	−0.0095	0.0030	−3.15	0.0016
Chronic renal diseases	0.0134	0.0074	1.81	0.0701
Peripheral vascular diseases	0.0215	0.0141	1.52	0.1290
Multidrug combination vs monotherapy	0.0221	0.0029	7.7	<0.0001
Visit to tertiary hospital	0.0821	0.0031	26.05	<0.0001
Number of hospitalizations	−0.0402	0.0030	−13.4	<0.0001
Average reimbursement ratio	0.1151	0.0042	27.05	<0.0001
Drug in the first prescription (benazepril alone as control)
Nifedipine GITs	0.2829	0.0069	41.05	<0.0001
Amlodipine	0.1359	0.0065	20.78	<0.0001
Metoprolol	−0.1126	0.0068	−16.46	<0.0001
Valsartan	0.2553	0.0072	35.38	<0.0001
Indapamide	0.1024	0.0109	9.41	<0.0001
Valsartan/amlodipine FDC	0.2327	0.0118	19.74	<0.0001
Combination of two or more drugs	0.2825	0.0073	38.42	<0.0001

Abbreviations: FDC, fixed-dose combination; GITs, gastrointestinal tablets.