The Burden of Chronic Obstructive Pulmonary Disease in Cardiovascular Diseases: A Non-Western Perspective.

Our previous article summarized the prevalence, complications, and implications of managing chronic obstructive pulmonary disease (COPD) in cardiovascular disorders (CVD) [1]. A critical limitation of the review was the predominance of cardiovascular disease and comorbid COPD data from the United States and Europe. This was mainly due to greater cardiovascular disease registries in the United States and Europe vs. the rest of the world. It becomes necessary to highlight a “non-Western” perspective for the prevalence of COPD in CVD at the regional level for guiding clinical decisions that will optimize resources and improve patients’ quality of life.

We reviewed the literature for the studies, which captured the status of comorbid COPD in cardiac patients, and were conducted in Asia, the Middle East, Africa, and South America conducted between 1981 to May 2020. The prevalence of COPD in heart failure (HF) and COPD in ischemic heart disease (IHD) and atrial fibrillation (AF) across different regions have been summarized in Tables 1 and 2, respectively.

Table 1.

Prevalence of COPD in HF registries outside of Europe and the United States

Study	Prevalence of COPD in the study (%)	Prevalence of COPD in general population by spirometry (%)	Method of COPD diagnosis	Country	Region
CONAREC-1999 [5]	16.10	14.5 [6]	History and/or clinical examination	Argentina	South America
IC-SAC-2002 [5]	19			Argentina
IC-SAC-2004 [5]	13.80			Argentina
CONAREC-2004 [5]	13.80			Argentina
Barretto et al. [2]	3.85	15.8 [7]		Brazil
Niteroi Study [8]	23			Brazil
INTER-CHF - South America [9]	10			Argentina, Chile, Colombia, and Ecuador
Yoshihisa et al. [10]	28	8.6 [11]	Spirometry	Japan	Asia
Onishi et al. [12]	27		Spirometry	Japan
JASPER HHF [13]	7.70		Medical records	Japan
KorAHF [14]	11	13.4 [15]	Clinical and/or history	Korea
China PEACE [16]	30.40	13.6 [17]		China
INTER-CHF - China [9]	8			China
HERO HF [18]	9.50			China
Trivandrum Heart Failure registry [19]	15.40	4.2 [20]		India
INTER_CHF India [9]	16			India
INTER_CHF_Malaysia and Philipines [9]	4			Malaysia and Philippines
INTER-CHF Middle east [9]	4			Egypt, Qatar, and Saudi Arabia	Middle East
Alhabeeb et al. [21]	19.70	4.2 [22]		Saudi Arabia
INTERCHF Africa [9]	2			Mozambique, Nigeria, South Africa, Sudan, and Uganda	Africa

COPD: chronic obstructive pulmonary disease; HF: heart failure.

Table 2.

Prevalence of COPD in IHD/AF registries outside of Europe and the United States

		Prevalence of COPD in the study (%)	Method of COPD diagnosis	Country	Region
IHD
	Gagliardi et al. [23]	3.9	Medical records/clinical examination/history	Argentina	South America
	Garcia Aurelio et al. [24]	6		Argentina
	Korea AMI Registry [25]	2.1		Korea	Asia
	National Health Insurance database [26]	28.3		Taiwan
	Das et al. [27]	52	Spirometry	India
	Mahendra et al. [28]	11		India
	Jayamani and Chopra [29]	11.5		India
	Khassawneh et al. [4]	15.7		Jordan	Middle East and Africa
	GULF RACE [30]	5.3	Medical records	Bahrain, Kuwait, Qatar, Oman, United Arab Emirates, and Yemen
	Ibnian et al. [31]	12.4	Spirometry	Jordan
	Yangui et al. [32]	20.5		Tunisia
AF
	Albina et al. [33]	7.7	Medical records/clinical examination/history	Argentina	South America
	Yang et al. [34,35]	11.7	Spirometry	China	Asia
	JCARE-CARD [36]	6.2	Medical records/clinical examination/history	Japan
	IHRS-AF [37]	7.8		India
	GULF SAFE [38]	5.3		Bahrain, Kuwait, Qatar, Oman, United Arab Emirates, and Yemen	Middle East

COPD: chronic obstructive pulmonary disease; IHD: ischemic heart disease; AF: atrial fibrillation.

One of the critical limitations of the evidence presented above has been the use of history/physical examination to diagnose COPD in cardiovascular disease patients. The prevalence varies from 3% to 30% in HF; the differences in prevalence can be accounted by reliance on clinical examination/history/medical records, instead of lung function tests, to make a diagnosis. We now know that use of history/physical examination/medication can lead to both over-diagnosis and under-diagnosis of COPD. However, in the regions under consideration, it is prudent to assume that under-diagnosis of COPD is much more common than over-diagnosis, leading to poor health outcomes and increased healthcare costs in the long run. Another factor to look at is the general prevalence of COPD in the country where studies were conducted. One would expect at-least equal or ideally higher prevalence of COPD in HF/AF/IHD versus general population (Table 1) because of the common risk factors involved in pathogenesis of both COPD and heart disease. In certain studies such as the one by Barretto et al. [2], the drastic difference in study reported COPD prevalence and general COPD prevalence might be due to recruiting bias and/or improper evaluation of airflow limitation leading to under-diagnosis of COPD.

Based on the evidence, we found that the burden of undiagnosed COPD in CVD remains high in the non-western regions of the world. Not surprisingly, 23% of patients with CVD have been shown to have spirometry-confirmed COPD in India [3]. In the middle east, 91.5% of patients with IHD with COPD were not previously diagnosed with COPD [4]. The results highlight the importance of active screening for COPD in CVD patients in these regions because of the potential to reduce long-term healthcare costs and morbidity amidst the resource constraints and predominance of risk factors for COPD and CVD progression.