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10.1136/bmjopen-2023-074711
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Original Research
Health Economics
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Estimation and determinants of direct hospitalisation cost for coronary heart disease in a low-middle-income country: evidence from a nationwide study in Iranian hospitals
http://orcid.org/0000-0002-5852-9375
Kazemi Zohreh 12zohkazemi2020@gmail.com

http://orcid.org/0000-0001-8654-6554
Emamgholipour Sara 2s-emamgholipour@tums.ac.ir

http://orcid.org/0000-0002-0487-4114
Daroudi Rajabali 23rdaroudi@sina.tums.ac.ir

http://orcid.org/0000-0002-2870-7433
Yunesian Masud 45yunesian@tums.ac.ir

Hassanvand Mohammad Sadegh 45hassanvand@tums.ac.ir

1 Department of Health Information Technology, Ferdows Faculty of Medical Sciences, Birjand University of Medical Sciences, Birjand, Iran (the Islamic Republic of)
2 Department of Health Management, policy and Economics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran (the Islamic Republic of)
3 National Center for Health Insurance Research, Tehran, Iran (the Islamic Republic of)
4 Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran (the Islamic Republic of)
5 Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran (the Islamic Republic of)
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DrSaraEmamgholipour; s-emamgholipour@tums.ac.ir
2024
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14 8 e07471114 4 2023
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Abstract

Background

Coronary heart disease (CHD) is the most prevalent type of cardiovascular disease in Iran. This study aims to investigate the estimation and determinants of direct hospitalisation cost for patients with CHD in Iranian hospitals.

Methods

We identified patients with CHD in Iran in 2019–2020. Data were gathered from the Iran Health Insurance Organisation information systems and the Ministry of Health and Medical Education. This was a cross-sectional prevalence-based study. Generalised linear models were used to find the determinants of hospitalisation cost for patients with CHD. A total of 86 834 patients suffering from CHD were studied.

Results

Mean hospitalisation cost per CHD patient was US$382.90±US$500.72 while the mean daily hospitalisation cost per CHD patient was US$89.71±US$89.99. In-hospital mortality of CHD was 2.52%. Hospitalisation accommodation and medications had the highest share of hospitalisation costs (25.59% and 22.63%, respectively). Men spent 1.12 (95% CI 1.11 to 1.13) times more on hospitalisation costs compared with women, and individuals aged 60 to 69 had hospitalisation costs 1.04 (95% CI 1.02 to 1.06) times higher than those in the 0–49 age range. Patients insured by the Iranian Fund have significantly higher costs 1.17 (95% CI 1.14 to 1.19) than the Rural fund. Hospitalisation costs for patients with CHD who received surgery and angiography were significantly 2.36 (95% CI 2.30 to 2.43) times higher than for patients who did not undergo surgery and angiography.

Conclusion

Applying CHD prevention strategies for men and the middle-aged population (50–70 years) is strongly recommended. Prudent use and prescribing of medications will be helpful to reduce hospitalisation cost.

coronary heart disease
hospitalization
ischaemic heart disease
health economics
health policy
==== Body
pmcSTRENGTHS AND LIMITATIONS OF THIS STUDY

The result can be generalised at the national level.

Determinants of coronary heart disease costs are obtained in the form of average cost ratio for usability and comparability by health policy-makers worldwide.

This study is limited by the absence of socioeconomic data, such as information on income, education and occupation.

Introduction

Cardiovascular disease (CVD) is a non-communicable illness that is commonly cited as a major contributor to early mortality and rising healthcare expenses.1 2 In general, dietary practices, lifestyle choices, accessibility to proper and sufficient healthcare and other variables affect the incidence and death rate of CVD in different geographical areas. For instance, patients with lower levels of education in low-income and middle-income countries (LMICs) have greater rates of CVD incidence and death.3 4

Patients from LMICs, mostly in the Eastern Mediterranean Region (EMR), which has been experiencing an epidemic crisis over the last several years, shoulder 50% of CVD mortality and 80% of the worldwide burden of CVDs.5 6 Given that CVDs are the third-largest contributor to the burden of illness in Iran,7 Iran seems to have the greatest burden of CVDs in the EMR.6 8

The leading cause of CVD is coronary heart disease (CHD), also known as ischaemic heart disease (IHD).9 CHD is the primary cause of death worldwide, and the burden of CHD in terms of disability-adjusted life-years (DALYs) is growing. The total number of prevalent, deaths and DALYs due to CHD has steadily increased from 1990 to 2019, reaching 197 million (103.54% increase), 9.14 million (60.42% increase) and 182 million (50.35% increase) by 2019, respectively; with the majority of the burden borne by those living outside of high-income countries. The majority of the global increase in CHD burden has been attributed to population growth and ageing.10 11

Burden of CHD is increasing in LMICs, including Iran.12 In the majority of LMICs, not only has CHD mortality increased, but it also poses a greater risk of prevalence and disability.13CHD is the most prevalent type of CVD in Iran. In the year 2019, a comparison of the global death rate, prevalence and DALY rate per 100 000 population with those of Iran revealed the following figures: 118.1 vs 121.95, 2548.89 vs 5143.08 and 2352.58 vs 2402.7, respectively. These results demonstrate that across these metrics, Iran exhibited higher rates than the global averages. In addition, from 1990 to 2019, the total number of prevalent, deaths and DALYs due to CHD in Iran has steadily increased, reaching 4.33 million (191.15% increase), 0.103 million (84.66% increase) and 2.025 million (45.41% increase) by 2019, respectively.11

Despite the resources expended on CHD treatment, the magnitude of cost components for various varieties of CHD and the variations in cost based on the differences in patient and provider characteristics remain unknown. Generally, LMICs lack a comprehensive disease registration system and precise financial records, which impedes the ability to conduct disease-specific cost analyses.14 Several studies have been carried out in Iran focusing on the cost and economic burden of CHD. However, these investigations frequently relied on data from a single local hospital, with limited sample size that is not generalisable.15 16 Notably, the Iran Health Insurance Organisation (IHIO) has granted unprecedented access to its expansive dataset. This groundbreaking study is the first of its kind to seize this opportunity and undertake a nationwide investigation.

Despite the considerable burden of CHD, limited studies have been conducted on the cost and economic burden of CHD in Iran. Previous research in this area has not provided information on the various cost components or the expenses associated with different types of CHD.15 16 Our study has specifically aimed to address this gap.

Objectives

The analysis of hospitalisation costs related to CHD offers significant insights into a range of decision-making processes in healthcare. These include resource planning, prioritisation, and allocation, as well as economic evaluation of health interventions. Additionally, it enables the identification of funding inefficiencies and opportunities for cost reduction, benefiting policy-makers, insurance organisations and healthcare providers.14 17 18 Hence, the primary objective of this study is to ascertain the hospitalisation expenses associated with CHD in Iran, along with its many components. Additionally, this research seeks to explore the factors that influence the cost of CHD hospitalisation, including patient characteristics, hospital features and the hospitalisation process.

Methods

Study design and setting

On the population of individuals covered by the IHIO, a cross-sectional survey based on CHD prevalence was conducted. Iran offers three kinds of fundamental health insurance. IHIO encompasses more than 50% of Iran’s population. Following the acquisition of the necessary permits, the study objectives and data requirements were initially discussed with IHIO officials in a formal face-to-face meeting. Subsequently, a written request for access to the required data along with a predesigned structured case report form (CRF) in Excel format was submitted.

The information regarding hospitalised CHD patients’ diagnoses in 2019–2020 (23 August 2019–21 June 2020) was extracted from this organisation’s information systems, which are linked to hospital information systems and financial records in hospitals across the country. The hospitalisation cost of CHD was determined using a healthcare system perspective with a bottom-up (microcosting) approach, in which patient-specific data were collected based on their utilisation of valued hospital services.19

Data, participants and eligibility criteria

The investigation included hospitalised patients with CHD diseases corresponding to ICD-10 (International Classification of Diseases, Tenth Revision) final diagnosis codes I20–I25. Unstable angina (ICD-10: I20), myocardial infarction (MI) (ICD-10: I21–I23) and IHD (ICD-10: I24–I25) were subtypes of patients with CHD. Data on patient demographics (14 items), cost components (55 items), illness and patient hospitalisation processes (36 items) and hospital features (7 items) were extracted from medical records using a CRF. Experts at the Iranian National Center for Health Insurance Research retrieved patient data from IHIO information records. The data on hospital features were gathered from the Ministry of Health and Medical Education’s accrediting sources for such facilities. Data extracted from two datasets were integrated. The cost components were then summarised and divided into eight groups: visit and consultation, lodging and nursing, laboratory, imaging, medication and medical supplies, rehabilitation, surgery and medical interventions.

This research did not use sampling; instead, it used a comprehensive enumeration approach. Thus, this is comprehensive research that includes all hospitalised patients with CHD covered by IHIO at the linked hospitals located across Iran. A total of 137 101 medical records were found in this research, however, 50 267 instances had to be eliminated since they matched with the exclusion criteria that explained below. This left 86 834 records for analysis.

Short-term and transient emergency department patients, as they were not categorised as hospitalised (n=14 685).2 Patients who, in the judgement of a cardiologist, had a lengths of stay (LoS) of 1 day or fewer (n=33 985).3 Medical records lacking crucial information, such as the LoS and accreditation level (newly founded hospitals that MHME (Ministry of Health and Medical Education) had not yet approved; n=1597).

This research did not directly engage the subjects. The unidentified entries in the IHIO database were the only ones included in the research population.

Variables

The research’s outcome variable was the cost of hospitalisation. Hospitalisation costs are the upfront expenses patients with CHD make when they are in the hospital. For the sake of comparison, hospital expenses were first recorded in Iranian rials (IRR), then translated to and represented in US dollars (US$1=IRR149 000, as of 19 March 2020). Age, gender, the insurance plan that pays for the patient (insurance fund), LoS in a cardiac care unit (CCU) bed (CCU-LoS), total LoS in hospital (total LoS), CHD subtype, reception of surgery and angiography, outcome of hospitalisation, hospital accreditation grade, ownership of the hospital and hospital size are all independent variables in this study.

LoS variables were classified into three categories. Because of the abundance of observations in the study (86 834 patients), there were initially numerous categories for the LoS variables (17 categories Based on common formulas for calculating the number of categories). According to the recommendations of epidemiologists and experts, some categories were merged, and the overall number of categories was eventually reduced to 3 to enhance the effectiveness and utility of the results for policy-makers.

Hospital accreditation involves a thorough external assessment of a hospital’s structure, procedures and outcomes using established, evidence based and standards.20 The tariffs established by the MHME in Iran are determined by the accreditation status of hospitals. Therefore, hospitals with superior accreditation grades will have higher fees.21 Iranian hospitals may be divided into four ownership categories: public, private, social security and special (military, charitable and other organisations). Public hospitals have subsidised rates whereas private sector hospitals are more costly, and this is true regardless of their accreditation grade.22 The two tariff levels are mixed in social security and special hospitals.

Statistical analysis

To ensure accuracy and consistency, all obtained data were randomly double-checked after being entered into Microsoft Excel spreadsheet CRFs. Following data cleaning, the data analysis was carried out using the STATA V.14.1 software package developed by StataCorp .

The cost distributions outlined in this study are not negative and exhibit a pronounced positive skewness. This aligns with the commonly reported results found in previous studies.2325 The factors that affect how much patients with CHD must spend on hospitalisation were identified using generalised linear models (GLM) with gamma family distribution and log link. Continuous data were examined for normality using the skewness and kurtosis normality tests. Cost, patient demographics, illness, patient hospitalisation procedure and hospital features were all summarised using descriptive statistics. Continuous data were displayed as mean along with SD or as median with lower quartile and upper quartile (25th and 75th percentiles) while categorical variables were summarised as count and percentage. The means and medians for central tendency, SD with the 25th and 75th percentiles for variability and dispersion, as well as the means and medians for each of our eight cost groups were reported in order to be able to estimate hospitalisation cost, daily cost and cost components (for each of our eight cost groups) and to give a full sense of the distribution of cost data. Hospitalisation costs are the total of all direct medical and non-medical expenses incurred when patients with CHD are hospitalised.26

It has been shown that the GLM with gamma distribution accurately predicts mean expenses (and therefore the total hospitalisation cost).17 27In contrast to the log transformation, the log link offers the benefit of assuring nonnegative results while keeping the data’s original scale. The linkage function, the proper functional form, was discovered using the Box-Cox method, and the distribution family was chosen using the modified Park test. Additionally, non-nested choices from six distinct patterns of the gamma, Gaussian and Poisson distribution families were examined using 40 iterations of the log and second root linkage functions, and their results were compared using the Akaike and Bayesian criterion. The lowest Akaike and Bayesian criteria were found for the log link and gamma family distributions, which supports the fitting model’s decent nature. The backward elimination technique was used to select variables for inclusion in the model. Statistics were deemed significant for p values under 0.05. β coefficients are presented with a 95% CI. Confounding factors were taken out using multivariate analysis.

Patient and public involvement

Patients and/or the public were not involved in this research’s design, conduct, reporting or dissemination plans.

Results

A total of 86 834 patients with CHD were included in the research, of which 29 690 (34.19%) had UA (mean age: 64±13 years, gender: 48.89% male) and 15 614 (17.98%) had MI (mean age: 65±13 years, gender: 66.91% male) and 41 530 (47.83% male) had IHD (mean age: 64±13 years, gender: 54.36% male). Table 1 displays the demographic and hospitalisation characteristics of studied population.

Table 1 Demographic and hospitalisation characteristics of the studied population

Characteristics	Unstable angina(n=29 690, ratio=34.19%)	Myocardial infraction(n=15 614, ratio=17.98%)	Ischaemic heart disease (n=41 530, ratio=47.83%)	Coronary heart disease(n=86 834, ratio=100%)	
Age, years, mean±SD (min-max)	64±13 (1–121)	65±13 (1–108)	64±13 (1–111)	64±13 (1–121)	
Gender					
 Male	14 515 (48.89)	10 448 (66.91)	22 574 (54.36)	47 537 (54.74)	
 Female	15 175 (51.11)	5166 (33.09)	18 956 (45.64)	39 297 (45.26)	
Marital status		
 Married	13 074 (44.04)	6449 (41.30)	18 426 (44.37)	34 949 (43.70)	
 Single	16 472 (55.48)	9093 (58.24)	22 949 (55.26)	48 514 (55.87)	
 Unspecified	144 (0.48)	72 (0.46)	155 (0.37)	371 (0.43)	
Insurance coverage and funds		
 Rural fund	14 373 (48.41)	7036 (45.06)	19 264 (46.39)	40 673 (46.48)	
 Other strata	2261 (7.62)	1081 (6.92)	2940 (7.08)	6282 (7.23)	
 Civil servants fund	5997 (20.20)	3074 (19.69)	8270 (19.91)	17 341 (19.97)	
 Iranian Fund	1118 (3.77)	1026 (6.57)	2267 (5.46)	4411 (5.08)	
 Universal health insurance	4270 (14.38)	2632 (16.86)	6488 (15.62)	13 390 (15.42)	
 Imam Khomeini Relief Committee	1671 (5.62)	765 (4.90)	2301 (5.54)	4737 (5.46)	
 CCU-LoS (mean±SD)	1.92±2.64	3.24±4.16	2.35±3.76	2.37±3.53	
 Other ward LoS (mean±SD)	1.86±2.70	1.50±4.90	2.54±3.54	2.12±3.60	
 Total LoS (mean±SD)	3.78±3.66	4.74±6.40	4.90±5.25	4.49±5.04	
Reception of surgery and angiography		
 No	23 617 (79.55)	8772 (56.18)	20 372 (49.05)	57 761 (60.76)	
 Surgery	5139 (17.31)	6140 (39.32)	18 333 (44.14)	29 612 (34.10)	
 Angiography	535 (1.80)	379 (2.43)	755 (1.82)	1669 (1.92)	
 Surgery and angiography	399 (1.34)	323 (2.07)	2070 (4.98)	2792 (3.22)	
Hospital accreditation grade		
 Grade 1	25 231 (85.28)	14 058 (91.16)	38 130 (93.17)	77 419 (90.09)	
 Grade 2	4106 (13.88)	1301 (8.44)	2192 (5.36)	7599 (8.84)	
 Grades 3 and 4	250 (0.84)	63 (0.41)	602 (1.47)	915 (1.06)	
Ownership of the hospital		
 Governmental	29 064 (98.23)	15 251 (98.89)	39 811 (97.28)	84 126 (97.90)	
 Private	69 (0.23)	36 (0.23)	590 (1.44)	695 (0.81)	
 Special (military, charity, other organisations)	430 (1.45)	111 (0.72)	502 (1.23)	1043 (1.21)	
 Social security	24 (0.08)	24 (0.16)	20 (0.05)	68 (0.08)	
Hospital size		
 ≤100 Bed or S	4702 (16.02)	1394 (9.07)	2891 (7.16)	8987 (10.56)	
 100–320 Bed or M	18 804 (64.06)	10 601 (69.01)	24 414 (60.46)	53 819 (63.24)	
 320–600 Bed or L	3851 (13.12)	2347 (15.28)	8566 (21.21)	14 764 (17.35)	
 600–1000 Bed or XL	1924 (6.55)	1017 (6.62)	4352 (10.78)	7293 (8.57)	
 >1000 Bed or HC	75 (0.26)	2 (0.01)	158 (0.39)	235 (0.28)	
Outcome of treatment		
 Alive	29 441 (99.16)	14 680 (94.02)	40 524 (97.58)	84 645 (97.48)	
 Death	249 (0.84)	934 (5.98)	1006 (2.42)	2189 (2.52)	
CCUcardiac care unitLoSlengths of stay

The average LoS in the hospital varied by types of CHD: 3.78±3.66 days (mean±SD) for UA, 4.74±6.40 days for MI, 4.90±5.25 days for IHD and 4.49±5.04 days for CHD. The average LoS in the CCU was 2.37±3.53 days, and in other wards, it was 2.12±3.60 days. The in-hospital mortality rates among patients hospitalised with UA, MI, IHD and CHD were 0.84%, 5.98%, 2.42% and 2.52%, respectively.

Total and daily hospitalisation cost per patient with CHD

Table 2 displays various cost components related to hospitalisation for the patients with CHD in the study. Hospitalisation cost per patient with CHD was US$218.90±US$315.14 (mean±SD) for UA, US$464.89±US$506.09 for MI, US$469.31±US$527.47 for IHD and US$382.90±US$500.72 for CHD. Patients with IHD had the highest mean hospitalisation cost per patient compared with the others.

Table 2 Hospitalisation cost for patients with CHD, stratified by resource utilisation and CHD type

Cost component*	Unstable angina	Myocardial infraction	Ischaemic heart disease	CHD	
In-hospital lodging and nursing	 	 	 	 	
 Mean±SD	74.24±102.09	117.50±203.40	107.60±163.18	97.97±155.06	
 Median (25th–75th percentile)	54.24 (38.81–81.37)	81.37 (57.07–118.37)	58.46 ((35.07–108.49)	62.20 (38.81–102.64)	
 % of total hospitalisation costs	33.91	25.27	22.93	25.59	
Medication and medical supplies	 	 	 	 	
 Mean±SD	38.35±98.19	120.72±155.16	108.48±162.15	86.71±146.41	
 Median (25th–75th percentile)	9.11 (5.54–20.55)	68.21 (13.66–197.55)	25.58 (9.26–191.01)	18.95 (7.56–90.62)	
 % of total hospitalisation costs	17.50	25.95	23.10	22.63	
Visit and consultation	 	 	 	 	
 Mean±SD	20.98±17.93	25.84±33.23	24.47±28.96	23.40±26.38	
 Median (25th–75th percentile)	17.50 (11.50–25.30)	18.69 (10.87–30.19)	17.25 (9.78–28.46)	17.56 (10.64–27.25)	
 % of total hospitalisation costs	9.17	4.96	4.09	5.28	
Medical imaging services	 	 	 	 	
 Mean±SD	14.93±26.37	21.20±39.79	25.05±44.87	20.91±38.83	
 Median (25th–75th percentile)	9.53 (5.50–14.70)	11.24 (6.51–19.99)	10.86 (5.51–24.09)	10.31 (5.54–19.09)	
 % of total hospitalisation costs	6.36	4.27	5.01	5.11	
Laboratory tests	 	 	 	 	
 Mean±SD	8.14±12.82	11.86±19.57)	15.38±26.60)	12.24±21.71)	
 Median (25th–75th percentile)	5.92 (4.10–8.49)	7.17 (4.76–11.48)	6.71 (4.11–13.25)	6.42 (4.21–10.57)	
 % of total hospitalisation costs	3.70	2.53	3.19	3.15	
Surgery	 	 	 	 	
 Mean±SD	117.65±109.92	174.99±123.41)	168.60±140.12)	161.17±133.64)	
 Median (25th–75th percentile)	71.58 (42.25–173.84)	167.42 (71.58–257.60)	122.03 (60.13–257.66)	119.12 (52.72–245.33)	
 % of total hospitalisation costs	10.03	15.58	17.65	15.71	
Rehabilitation	 	 	 	 	
 Mean±SD	21.54±61.75	68.42±106.67	43.66±89.67	46.02±91.57	
 Median (25th–75th percentile)	5.66 (3.61–8.03)	10.80 (4.86–121.19)	7.53 (4.63–22.59)	7.53 (4.76–27.61)	
 % of total hospitalisation costs	0.23	1.15	0.94	0.85	
Medical interventions	 	 	 	 	
 Mean±SD	15.86±44.65	33.97±79.27	46.83±89.45)	34.29±77.01	
 Median (25th–75th percentile)	5.66 (0.75–9.29)	8.03 (4.86–13.81)	8.03 (4.86–29.60)	7.32 (4.54–14.09)	
 % of total hospitalisation costs	0.78	1.19	1.14	1.08	
Total hospitalisation cost	 	 	 	 	
 Mean±SD	218.90±315.14	464.89±506.09	469.31±572.47	382.90±500.72	
 Median (25th–75th percentile)	132.41 (94.55–208.38)	291.69 (178.92–630.12)	216.53 (128.41–631.07)	186.33 (116.46–472.98)	
* Costs expressed in United StatesS dollars ().

CHDcoronary heart disease

The primary cost component for hospitals related to CHD is in-hospital housing and nursing, which accounts for 25.59% of the total expenses. Following this, the subsequent components in terms of severity include medication and medical supplies (22.63%), surgery (15.71%), visit and consultation (5.28%), medical imaging services (5.11%), laboratory tests (3.15%), medical interventions (1.08%) and rehabilitation (0.85%). Notably, rehabilitation represents the smallest fraction of the overall expenditure per patient with CHD in hospital settings.

Further details about total and daily hospitalisation cost for patients with CHD stratified by LoS and CHD types are presented in online supplemental table 1. Hospitalisation cost for patients with CHD, stratified by age, gender and CHD types can be found in online supplemental table 2.

Determinants of hospitalisation cost for patients with CHD

Table 3 presents the factors influencing the cost of hospitalisation for patients with CHD in Iran. The independent factors included in the GLM were age, gender, insurance funds, LoS in the CCU, LoS in other words, subtypes of CHD, receipt of surgery and angiography, hospital accreditation grade, ownership of the hospital and hospital size.

Table 3 Determinants of hospitalisation cost for patients suffering CHD in Iran

Variables		N	%	Coefficient (β)	95% CI	P value	
Lower	Upper		
Age	≤49	11 116	12.80	1				
50–59	20 282	23.36	1.03	1.02	1.05	<0.001	
60–69	26 785	30.85	1.04	1.02	1.06	<0.001	
70–79	17 418	20.06	1.02	1.00	1.04	0.008	
≥80	11 233	12.94	0.96	0.94	0.98	<0.001	
Gender	Female	39 297	45.26	1				
Male	47 537	54.74	1.12	1.11	1.13	<0.001	
Insurance coverage and funds	Rural fund	40 673	46.48	1				
Other strata	6282	7.23	0.99	0.97	1.01	0.214	
Civil servants fund	17 341	19.97	1.04	1.03	1.05	<0.001	
Iranian fund	4411	5.08	1.17	1.14	1.19	<0.001	
Universal health insurance	13 390	15.42	1.03	1.01	1.04	<0.001	
Imam Khomeini Relief Committee	4737	5.46	0.96	0.94	0.98	<0.001	
CCU-LoS	0 days	26 816	30.88	1				
1–2 days	29,739	34.25	1.37	1.36	1.39	<0.001	
≥3 days	30 279	34.87	1.64	1.62	1.66	<0.001	
	2–3 days	50 175	57.78	1				
Total LoS	4–7 days	26 396	30.40	1.44	1.42	1.46	<0.001	
	≥8 days	10 263	11.82	2.86	2.81	2.91	<0.001	
CHD type	Unstable angina	29 690	34.19	1				
Ischaemic heart disease	41 530	47.83	1.29	1.27	1.30	<0.001	
Myocardial infraction	15 614	17.98	1.42	1.40	1.44	<0.001	
Surgery and angiography reception	No	57 761	60.76	1				
Surgery	29 612	34.01	2.56	2.53	2.59	<0.001	
Angiography	1669	1.92	2.61	2.53	2.71	<0.001	
Surgery and angiography	2792	3.22	2.36	2.30	2.43	<0.001	
Hospital accreditation grade	Grades 3 and 4	915	1.06	1				
Grade 1	77 419	90.09	1.40	1.27	1.56	<0.001	
Grade 2	7599	8.84	1.30	1.17	1.45	<0.001	
Ownership of the hospital	Governmental	84 126	97.90	1				
Special (military, charity, other organisations)	1043	1.21	1.50	1.44	1.56	<0.001	
Social security	68	0.08	1.24	1.06	1.45	0.007	
Private	695	0.81	2.23	2.12	2.35	<0.001	
Hospital size	≤100 bed (S)	8987	10.56	1				
100–320 bed (M)	53 819	63.24	1.11	1.09	1.13	<0.001	
321–600 bed) (L)	14 764	17.35	1.37	1.34	1.40	<0.001	
601–1000 bed) (XL)	7293	8.57	1.05	1.03	1.07	<0.001	
>1000 bed) (HC)	235	0.28	1.40	1.28	1.53	<0.001	
Outcome of hospitalisation	Alive	84 645	97.48	1				
Death	2189	2.52	1.47	1.43	1.52	<0.001	
CCUcardiac care unitCHDcoronary heart diseaseLoSlengths of stay

Significant disparities were observed in hospitalisation costs among different age groups, with individuals in the 60–69 age group incurring the highest average hospitalisation costs. The average cost of hospitalisation increased by 1.03 (95% CI 1.02 to 1.05) times for individuals aged 50–59, 1.04 (95% CI 1.02 to 1.06) times for individuals aged 60–69 and 1.02 (95% CI 1.00 to 1.04) times for individuals aged 70–79 while it decreased by 0.96 (95% CI 0.94 to 0.98) times for those aged 80 years and older when compared with people in the 0–49 age range. Men spent 1.12 (95% CI 1.11 to 1.13) times higher on hospitalisation costs in comparison to women.

The average cost between patients covered by other strata fund and the rural fund reference group was found to be statistically insignificant in this investigation, with a p value of 0.214 (p>0.05). However, the average hospitalisation cost for insured individuals covered by the Civil Servants Fund, Iranians Fund and Universal Health Fund varied significantly from that of the insured individuals covered by the Rural Fund, with their average costs being 1.04 (95% CI 1.03 to 1.05), 1.17 (95% CI 1.14 to 1.19) and 1.03 (95% CI 1.01 to 1.04), times higher than those covered by rural fund, respectively. In contrast, the cost was 0.96 (95% CI 0.94 to 0.98) times lower for those covered by Imam Khomeini Relief Committee, compared with Rural Fund insureds.

The average hospitalisation cost for patients with CHD was significantly positively correlated with both CCU and total LoS. The cost was 2.86 (95% CI 2.81 to 2.91) times higher for patients with total LoS longer than 8 days compared with those with total LoS of 2–3 days, and 1.64 (95% CI 1.62 to 1.66) times higher for patients with CCU-LoS longer than 3 days compared with 0-day CCU-LoS.

A significant difference in average hospitalisation costs was observed among CHD patient subgroups. Patients with MI and IHD had hospitalisation costs that were, respectively, 1.42 (95% CI 1.40 to 1.44) and 1.29 (95% CI 1.27 to 1.30) times greater than those of UA patients. Patients with CHD who underwent angiography and surgery incurred mean hospitalisation costs that were significantly 2.36 (95% CI 2.30 to 2.43) times higher than those of the comparison group who did not undergo these procedures.

The average hospitalisation cost for patients with CHD was notably associated with the hospital accreditation grade. Expenditures for hospitals rated grades 1 and 2 were 1.4 (95% CI 1.27 to 1.56) and 1.3 (95% CI 1.17 to 1.45) times higher than those for hospitals with grades 3 and 4, respectively. Special hospitals (military, charitable and others), social security and private hospitals all exhibited significantly higher average hospitalisation costs for patients with CHD compared with governmental hospitals, with cost ratios of 1.50 (95% CI 1.44 to 1.56), 1.24 (95% CI 1.06 to 1.45) and 2.23 (95% CI 2.12 to 2.35) times higher, respectively.

As the hospital size and number of beds increased, the average cost for hospitalised patients with CHD also rose. Medium hospitals saw a 1.11 (95% CI 1.09 to 1.13)-fold increase, large hospitals showed a 1.37 (95% CI 1.34 to 1.40)-fold increase, very large hospitals experienced a 1.05 (95% CI 1.03 to 1.07)-fold increase and hospital complexes observed a 1.40 (95% CI 1.28 to 1.53)-fold increase compared with small hospitals with less than 100 beds.

Analysis of hospitalisation outcomes revealed significant disparities in the mean hospitalisation cost of patients with CHD with mortality outcomes compared with the reference group of those who were alive; the average hospitalisation cost for deceased patients was 1.47 (95% CI 1.43 to 1.52) times higher than that of the alive group.

Discussion

Iran had a lower mean hospitalisation cost per patient with CHD than Brazil, Thailand and China, according to the present study.2830 The first two is developing nations, while the third is a developed nation. A systematic review of CVD and blood pressure in developing countries revealed that the cost of CHD is generally higher and more heterogeneous than other CVD diseases, so in some countries, the cost per patient was estimated to exceed US$5000. The average cost of treatment for this disease ranged between US$300 and US$1000, with wide variation in estimates.31

60%–80% of the costs of Iranian government hospitals are covered by the hospital’s specific revenues while 20%–40% are covered by government budgets and subsidies.32 Therefore, their prices are below the actual cost of providing services, and these prices do not accurately reflect the value of their services.

The lower prevalence of traditional medical technologies in Iran compared with modern, costly medical technologies,33 is a further factor contributing to this disparity. In addition, the difference in mean cost is likely attributable to differences in healthcare systems, disparities in care standards, payment systems, current advancements in healthcare technologies and services, sanctions imposed on Iran, and the precipitous decline in the value of the national currency, the IRR.

This study found significant differences in hospitalisation costs by age, gender and CHD subtypes similar to other studies.17 34 35 Hospitalisation costs increase with age until age 70. This could be attributed to the fact that elderly patients are less likely to be hospitalised, that physicians are less likely to perform invasive procedures such as surgery and angiography on them, and that they opted for relatively conservative therapies such as fewer cardiac stents and more pharmacotherapy.28 Given that over 54% of hospitalisation costs are attributable to the age group of 50–70 years, cost-reduction interventions should target this age group, that is, educational interventions and prevention strategies should be implemented in this age group (50–70 years).

Men incurred greater hospitalisation expenses than women.36 37 Matching these findings with epidemiological and clinical data facilitates the identification of CHD prevention targets and the development of cost-effective CHD programmes. Given higher CHD age-standardised incidence rate (1007.77 vs 652.03), prevalence rate (7597.05 vs 4815.78) and mortality rate (177.18 vs 150.93) per 100 000 in males than females in Iran, as well as higher direct hospitalisation costs for male patients with CHD, preventative and educational programmes aimed at men are cost-effective health interventions.11 38 39

Since the primary risk factors for CHD, such as dietary habits, lifestyle, smoking and alcohol use, differ between men and women, women in Middle Eastern countries, including Iran, have fewer hazardous habits (eg, smoking and alcohol use) than men.4042 Important and cost-effective CHD-reduction strategies include a greater emphasis on public health knowledge, tax policies on tobacco and nutrition, and direct government interventions to curb alcohol consumption.43

Costs for patients insured by the Imam Khomeini Relief Committee are substantially lower (0.96 times) than costs for the Rural fund reference group. Because the majority of hospitalisation services for this population are provided at no cost. Patients insured by the Iranian Fund have substantially higher costs (1.17 times) than those insured by other funds. Both the universal health insurance fund and the Iranian health insurance fund provide coverage for the indigent. These individuals typically receive coverage if they develop severe symptoms of the disease and are hospitalised. In the first, the individual’s entire insurance premium is paid by the government, whereas in the second, the government pays half of the premium and the insured pays the remainder. Insureds of the Iranian Fund are frequently in temporary socioeconomic distress, necessitating financial justification for government and health insurance policy-makers to provide spatial attention. In this regard, the transition to universal health coverage can be an effective measure for narrowing the disparity between all insured patients.

This study revealed that the highest proportion of hospitalisation expenses (25.59%) is attributable to lodging and nursing costs. The mean LoS for patients with CHD was 4.49 days, which was cLoSe to the mean LoS for patients with CHD in China (4 days) and Cameroon (5 days),17 28 although other studies reported longer mean LoS.9 44 In addition, the total cost of hospitalisation for patients with CHD with differing LOS was significantly different. Reducing superfluous days of LOS can be an essential factor in reducing patient and hospital costs, as it leads to an increase in productivity and a decrease in patient waiting times. Creating systems that define a standard for LOS control by increasing the patient admission rate and bed turnover will ultimately result in a revenue increase for the hospital. According to Aghababaei et al’s study, with the implementation of bed management at the Rajaie Cardiovascular Medical and Research Center in Tehran, Iran, LOS was cut in half, bed turnover increased from 10.57 to 21.14 times and hospital revenues increased by 33%, confirming the aforementioned claims.45 We found that admission to a CCU was significantly associated with higher hospitalisation expenses for patients with CHD. The hospitalisation cost for patients with CCU-LoS≥3 days is 1.67 times that of patients with CCU-LoS 0 days. In Iran, the cost of a 1-day hospitalisation in the CCU is approximately 2.32 times that of other hospital departments, and the higher coefficients of human resources per bed in the CCU can explain this difference.

Various forms of CHD have significantly different average hospitalisation costs. Clinically, MI is a more severe form of CHD than other varieties. It is Consistent with the findings of Wang et al in China.34 It is suggested that policy-makers consider these differences when allocating hospital resources and funds.

The hospitalisation cost for patients with CHD who underwent surgery and angiography was 2.61 times and 2.36 times that of patients who did not undergo surgery and angiography, respectively. Previous studies showed that approximately one-quarter of angiographies may be inappropriate and due to physician-induced demand.4648 Moreover, coronary angiography is an invasive procedure that places a substantial burden on both patients and the healthcare system and could cause complications and deaths, so performing non-invasive tests (such as heart scan, stress test, echocardiography) prior to surgery can reduce the number of unnecessary angiographies. Policy-makers are advised to implement financial benefits for clinicians, a value-based payment system in lieu of fee-for-service, and an effective supervisory-support system to mitigate this potential issue. There was a substantial disparity between the cost of hospitalisation for patients with CHD and hospital accreditation grades. Because hospital fees depend on the hospital’s level of accreditation. As hospitals of the highest quality (grade 1) have the highest fees, compared with hospitals of lower grades.

According to our estimates, the average cost of hospitalisation for patients with CHD in private hospitals is 2.23 times that in public hospitals. Private hospitals incur higher catastrophic costs than public hospitals, according to previous research.49 The reason for this disparity in Iran is that private hospitals charge more for accommodation (2.7times), surgery (4.3times), laboratory (2.3times) and visits (2.1times) than public hospitals.50 Public hospitals in Iran are subsidised by the government so their costs are lower than those of other hospitals. To convert the costs of public hospitals into social costs, we propose using the coefficients of the average cost ratio of special hospitals (1.509) in cost of illness studies, as these hospitals are almost entirely financed by their specific revenues and rely less on government budget and subsidies. We have also observed an increase in the average cost of hospitalisation for patients with CHD in tandem with the expansion of hospitals. Many small and medium-sized hospitals lack clinical expertise due to the difficulty of attracting and retaining specialist physicians. Another possibility is the delayed diffusion of new technologies and remedies to smaller hospitals that may lack access to CCUs, advanced care and transport for patients with CHD. These factors can result in the admission of patients with more severe CHD and, consequently, higher hospital costs in the larger hospitals. The average cost of hospitalisation for patients with CHD who died was higher than for those who survived. The deceased patients’ acute conditions necessitated a higher level of care, resulting in higher costs.

Despite the demonstrated benefits of cardiac rehabilitation (CR), such as ‘reducing risks of all-cause mortality, MI, all-cause hospitalisation and associated healthcare costs and improving health-related quality of life in people with CHD’,51 52 rehabilitation costs represent the smallest proportion of hospitalisation costs for each patient. During the patient’s hospitalisation, physicians may have paid insufficient attention to the CR prescription. Or, physicians may prescribe CR for patients with CHD as posthospitalisation care, which requires further research on the economic burden of CHD, and CR utilisation to be clarified. In addition, the scarcity of rehabilitation specialists and rehabilitation equipment in Iranian hospitals is the most significant obstacles to providing CR.

Especially in the event of MI, we recommend that the cardiologists prescribe CR to hospitalised cardiac patients in accordance with the CR standards established by the Ministry of Health. In addition, policy-makers should consider establishing and outfitting CR centres within hospitals that treat heart attacks.

IHIO data demonstrated capable of cost estimation for CHD-related hospitalisation and medical care utilisation on a national scale and also provided a thorough cost analysis for patients with CHD in Iran. Thus, the findings of this study are applicable and generalisable to the entire nation. We present hospitalisation cost determinants in the form of an average cost ratio, the results of which may be beneficial for policy-makers and healthcare providers in other nations. Due to a dearth of relevant and accessible clinical data, this study’s estimates do not account for CHD severity and comorbidities. In addition, it was not possible to examine the CHD cost for households based on socioeconomic variables such as income, education and occupation.

Conclusion

Hospitalisation costs can be influenced by a variety of factors, many of which can be used to develop evidence-based policies. Populations of patients with CHD insured by the Iranian Fund should be a policy-maker’s top priority in order to improve medical care outreach and expand access to affordable hospitalisation and medications. Migration to universal health coverage can be an effective means of narrowing the disparity between all insured patients. Applying CHD prevention strategies to men and the middle-aged (50–70 years) population is strongly advised.

Highly recommended to control and alter hospitalisation costs are the implementation of a bed management system in hospitals, as well as the prudent use and prescribing of medications. Performing noninvasive tests (such as cardiac scans, stress testing and echocardiography) prior to surgery, as well as designing guidelines and protocols to manage these cases, along with supervision and supportive regulatory rules, will encourage physicians. Given the advantages of CR, the required arrangements for CR should be made, including convincing cardiologists to prescribe CR in accordance with the standards of the Ministry of Health and outfitting CR centres in hospitals that manage heart attacks.

supplementary material

10.1136/bmjopen-2023-074711 online supplemental file 1

Acknowledgements

We thank Dr Ali Shojaee, Zahra Shahali and his colleagues at NCHIR and IHIO for their cooperation and providing data.

Data availability statement

Data are available on reasonable request.

Review Process File
7 8 2024

Funding: This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

Prepublication history and additional supplemental material for this paper are available online. To view these files, please visit the journal online (https://doi.org/10.1136/bmjopen-2023-074711).

Provenance and peer review: Not commissioned; externally peer reviewed.

Patient consent for publication: Not applicable.

Ethics approval: This research was part of a Ph.D. thesis approved by the Ethics Committee of Tehran University of Medical Sciences (code: IR.TUMS.SPH.REC.1398.229), and the research was conducted in accordance with the Declaration of Helsinki.

Patient and public involvement: Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.
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References

1 Vos T Lim SS Abbafati C et al Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the global burden of disease study 2019 Lancet 2020 396 1204 22 10.1016/S0140-6736(20)30925-9 33069326
2 Mensah GA Roth GA Fuster V The global burden of cardiovascular diseases and riskfactors: 2020 and beyond J Am Coll Cardiol 2019 74 2529 32 10.1016/j.jacc.2019.10.009 31727292
3 Rosengren A Smyth A Rangarajan S et al Socioeconomic status and risk of cardiovascular disease in 20 low-income, middle-income, and high-income countries: the prospective urban rural epidemiologic (PURE) study Lancet Glob Health 2019 7 e748 60 10.1016/S2214-109X(19)30045-2 31028013
4 Amini M Zayeri F Salehi M Trend analysis of cardiovascular disease mortality, incidence, and mortality-to-incidence ratio: results from global burden of disease study 2017 BMC Public Health 2021 21 401 10.1186/s12889-021-10429-0 33632204
5 Alwan A Global status report on noncommunicable diseases 2010 World Health Organization 2011
6 Sarrafzadegan N Mohammmadifard N Cardiovascular disease in iran in the last 40 years: prevalence, mortality, morbidity, challenges and strategies for cardiovascular prevention Arch Iran Med 2019 22 204 10 31126179
7 Eisavi M Mazaheri E Rezapour A et al The cost-effectiveness and cost-utility of statin drug for the treatment of patients with cardiovascular disease, a systematic review Int J Prev Med 2021 12 39 10.4103/ijpvm.IJPVM_125_20 34249288
8 Gaziano TA Bitton A Anand S et al Growing epidemic of coronary heart disease in low- and middle-income countries Curr Probl Cardiol 2010 35 72 115 10.1016/j.cpcardiol.2009.10.002 20109979
9 Wang L Wu X Du J et al Global burden of ischemic heart disease attributable to ambient PM2.5 pollution from 1990 to 2017 Chemosphere 2021 263 128134 10.1016/j.chemosphere.2020.128134 33297122
10 Roth GA Mensah GA Johnson CO et al Global burden of cardiovascular diseases and risk factors, 1990–2019 J Am Coll Cardiol 2020 76 2982 3021 10.1016/j.jacc.2020.11.010 33309175
11 GBD Compare 2019 Available https://vizhub.healthdata.org/gbd-compare
12 Uli RE Satyana RPU Zomer E et al Health and productivity burden of coronary heart disease in the working indonesian population using life-table modelling BMJ Open 2020 10 e039221 10.1136/bmjopen-2020-039221
13 Nowbar AN Howard JP Finegold JA et al 2014 global geographic analysis of mortality from ischaemic heart disease by country, age and income: statistics from world health organisation and united nations Int J Cardiol 2014 174 293 8 10.1016/j.ijcard.2014.04.096 24794549
14 Hendriks ME Kundu P Boers AC et al Step-by-step guideline for disease-specific costing studies in low- and middle-income countries: a mixed methodology Glob Health Action 2014 7 23573 10.3402/gha.v7.23573 24685170
15 Darba S Safaei N Mahboub-Ahari A et al Direct and indirect costs associated with coronary artery (heart) disease in Tabriz, Iran Risk Manag Healthc Policy 2020 13 969 78 10.2147/RMHP.S261612 32801971
16 Raghfar H Sargazi N Mehraban S et al The economic burden of coronary heart disease in iran: a bottom-up approach in 2014 J Ardabil Univ Med Sci 2018 18 341 56 10.29252/jarums.18.3.341
17 Aminde LN Dzudie A Mapoure YN et al Estimation and determinants of direct medical costs of ischaemic heart disease, stroke and hypertensive heart disease: evidence from two major hospitals in cameroon BMC Health Serv Res 2021 21 140 10.1186/s12913-021-06146-4 33579273
18 Diestro JDB Omar AT Sarmiento RJC et al Cost of hospitalization for stroke in a low-middle-income country: findings from a public tertiary hospital in the philippines Int J Stroke 2021 16 39 42 10.1177/1747493020906872 32075570
19 Jo C Cost-of-illness studies: concepts, scopes, and methods Clin Mol Hepatol 2014 20 327 37 10.3350/cmh.2014.20.4.327 25548737
20 Jeffrey B Russell M Yukihiro M et al Healthcare systems Iran: hospital accreditation: future directions Boca Raton : Taylor & Francis CRC Press 2018 297 303 Available https://www.taylorfrancis.com/books/9781351683722
21 Yousefinezhadi T Mosadeghrad AM Arab M et al An analysis of hospital accreditation policy in Iran Iran J Public Health 2017 46 1347 58 29308378
22 Mehraban S Raghfar H The place of health insurance in reducing catastrophic health expenditure Iran J Econ Stud 2018 7 239 54
23 Malehi AS Pourmotahari F Angali KA Statistical models for the analysis of skewed healthcare cost data: a simulation study Health Econ Rev 2015 5 11 10.1186/s13561-015-0045-7 26029491
24 Aung YN Nur AM Ismail A et al Determining the cost and length of stay at intensive care units and the factors influencing them in a teaching hospital in Malaysia Value Health Reg Issues 2020 21 149 56 10.1016/j.vhri.2019.09.006 31958748
25 Seghieri C Berta P Nuti S Geographic variation in inpatient costs for acute myocardial infarction care: insights from Italy Health Policy 2019 123 449 56 10.1016/j.healthpol.2019.01.010 30902531
26 Liu C Luo L Duan L et al Factors affecting in-hospital cost and mortality of patients with stroke: evidence from a case study in a tertiary hospital in China Int J Health Plann Manage 2021 36 399 422 10.1002/hpm.3090 33175426
27 Dodd S Bassi A Bodger K et al A comparison of multivariable regression models to analyse cost data J Eval Clin Pract 2006 12 76 86 10.1111/j.1365-2753.2006.00610.x
28 Ding JM Zhang XZ Hu XJ et al Analysis of hospitalization expenditures and influencing factors for inpatients with coronary heart disease in A tier-3 hospital in xi’an, China: A retrospective study Medicine (Baltimore) 2017 96 e9341 10.1097/MD.0000000000009341 29390516
29 Schlatter RP Hirakata VN Polanczyk CA Estimating the direct costs of ischemic heart disease: evidence from a teaching hospital in BRAZIL, a retrospective cohort study BMC Cardiovasc Disord 2017 17 180 10.1186/s12872-017-0615-1
30 Kiatchoosakun S Sutra S Thepsuthammarat K Coronary artery disease in the thai population: data from health situation analysis 2010 J Med Assoc Thai 2012 95 Suppl 7 S149 55
31 Gheorghe A Griffiths U Murphy A et al The economic burden of cardiovascular disease and hypertension in low- and middle-income countries: a systematic review BMC Public Health 2018 18 975 10.1186/s12889-018-5806-x 30081871
32 Afshari M Rostampour S Rostampour A et al Review of the cost and income of the affiliated hospitals of the Maragheh faculty of medical sciences and health services the first national conference on organizational transformation and innovation with a resistance economy approach, Mashhad 2015 Available https://civilica.com/doc/595483
33 Schroeck FR Jacobs BL Bhayani SB et al Cost of new technologies in prostate cancer treatment: systematic review of costs and cost effectiveness of robotic-assisted laparoscopic prostatectomy, intensity-modulated radiotherapy, and proton beam therapy Eur Urol 2017 72 712 35 10.1016/j.eururo.2017.03.028 28366513
34 Wang Q Zhang S Wang YL et al Factors associated with hospitalization costs of coronary heart disease in township hospitals in rural China Inquiry 2019 56 004695801988695 10.1177/0046958019886958
35 Nowbar AN Gitto M Howard JP et al Mortality from ischemic heart disease Circ Cardiovasc Qual Outcomes 2019 12 e005375 10.1161/CIRCOUTCOMES.118.005375 31163980
36 Brown DL Boden-Albala B Langa KM et al Projected costs of ischemic stroke in the United States Neurol (ECronicon) 2006 67 1390 5 10.1212/01.wnl.0000237024.16438.20
37 Wang G Zhang Z Ayala C et al Costs of hospitalization for stroke patients aged 18-64 years in the United States J Stroke Cerebrovasc Dis 2014 23 861 8 10.1016/j.jstrokecerebrovasdis.2013.07.017 23954598
38 Nouri F Feizi A Taheri M et al Temporal trends of the incidence of ischemic heart disease in iran over 15 years: A comprehensive report from a multi-centric hospital-based registry Clin Epidemiol 2020 12 847 56 10.2147/CLEP.S259953 32848474
39 Shohreh N Kimiya G Ali S et al Twenty-six-year trend of mortality rate due to ischemic heart diseases (IHDS) in Iran: 1990-2015 Iran J Public Health 2022 51
40 Zhao M Vaartjes I Graham I et al Sex differences in risk factor management of coronary heart disease across three regions Heart 2017 103 1587 94 10.1136/heartjnl-2017-311429 28931567
41 Shah T Palaskas N Ahmed A An update on gender disparities in coronary heart disease care Curr Atheroscler Rep 2016 18 28 10.1007/s11883-016-0574-5 27029220
42 Ramachandran HJ Wu VX Kowitlawakul Y et al Awareness, knowledge and healthy lifestyle behaviors related to coronary heart disease among women: an integrative review Heart & Lung 2016 45 173 85 10.1016/j.hrtlng.2016.02.004 26961078
43 Zhu D Shi X Nicholas S et al Medical service utilization and direct medical cost of stroke in urban china Int J Health Policy Manag 2020 10.34172/ijhpm.2020.111
44 Sözmen K Pekel Ö Yılmaz TS et al Determinants of inpatient costs of angina pectoris, myocardial infarction, and heart failure in a university hospital setting in Turkey Anatol J Cardiol 2015 15 325 33 10.5152/akd.2014.5320 25413230
45 Aghababaei M Noohi F Kyavar M et al Bed management system can increase hospital revenues: experiences of a referral cardiovascular center Iran Heart J 2021 22 6 16
46 Desai NR Bradley SM Parzynski CS et al Appropriate use criteria for coronary revascularization and trends in utilization, patient selection, and appropriateness of percutaneous coronary intervention JAMA 2015 314 2045 53 10.1001/jama.2015.13764 26551163
47 Hannan EL Samadashvili Z Cozzens K et al Appropriateness of diagnostic catheterization for suspected coronary artery disease in New York State Circ Cardiovasc Interv 2014 7 19 27 10.1161/CIRCINTERVENTIONS.113.000741 24474625
48 Mohammadshahi M Sefiddashti SE Sakha MA et al Appropriateness of angiography for suspected coronary artery disease Indian Heart J Teach Ser 2021 73 376 8 10.1016/j.ihj.2021.04.004
49 Buigut S Ettarh R Amendah DD Catastrophic health expenditure and its determinants in Kenya slum communities Int J Equity Health 2015 14 46 10.1186/s12939-015-0168-9 25971679
50 Doshmangir L Rashidian A Kouhi F et al Setting health care services tariffs in Iran: half a century quest for a window of opportunity Int J Equity Health 2020 19 112 10.1186/s12939-020-01224-1 32631344
51 Anderson L Thompson DR Oldridge N et al Exercise-based cardiac rehabilitation for coronary heart disease Cochrane Database Syst Rev 2016 2016 CD001800 10.1002/14651858.CD001800.pub3 26730878
52 Dibben G Faulkner J Oldridge N et al Exercise-based cardiac rehabilitation for coronary heart disease Cochrane Database Syst Rev 2021 11 CD001800 10.1002/14651858.CD001800.pub4 34741536
