|
 
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| REVIEW ARTICLE |
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| Year : 2020 | Volume
: 17
| Issue : 1 | Page : 21-26 |
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Cardiovascular diseases in Nigeria: What has happened in the past 20 years?
Samuel Obiajulu Ike1, Chuka Timothy Onyema2
1 Department of Medicine, University of Nigeria Teaching Hospital, Ituku Ozalla, Enugu, Nigeria
2 Department of Medicine, University of Nigeria Teaching Hospital, Ituku Ozalla, Enugu; Department of Internal Medicine, Alex Ekwueme Federal University Teaching Hospital, Abakaliki, Ebonyi, Nigeria
| Date of Submission | 31-Dec-2019 |
| Date of Decision | 17-Mar-2020 |
| Date of Acceptance | 28-Mar-2020 |
| Date of Web Publication | 30-Jun-2020 |
Correspondence Address:
Dr. Chuka Timothy Onyema
4 Aninwede Street, Ogui New Layout, Enugu
Nigeria
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/njc.njc_33_19
Cardiovascular diseases (CVDs) are a leading cause of death worldwide with an accelerated increase in CVD-related death in Nigeria and other low-income and middle-income countries. A review of the trend of presentation and management of CVDs in Nigeria over the past 20 years revealed a transition from high incidence of CVDs associated or resulting from poverty and malnutrition (such as rheumatic heart disease) initially to a fall in the prevalence of these poverty-related CVDs occurring subsequently at same time with a rising prevalence of other noncommunicable CVDs (such as hypertension and heart failure). Although some CVDs such as coronary heart disease and cardiomyopathies maintained a steady prevalence within the period in review, this trend was associated with changing availability of healthcare services in Nigeria, with better services and newer treatments becoming more available over time and increasing prevalence of CVD risk factors among Nigerians. Despite these, Nigeria is at a plateau now as a result of poor funding and support of the health sector. This has resulted in most health funding coming from donor agencies, religious bodies, philanthropists, and nongovernment organizations. For progress, there is a need for an increase focus in the health sector with increased funding and support from the government and all players. Increased awareness and education of the general population on the prevention and control of risk factors and training of health professionals on appropriate diagnosis and management of CVDs is advocated.
Keywords: Cardiovascular diseases, healthcare services, heart disease, risk factors, trend
How to cite this article:
Ike SO, Onyema CT. Cardiovascular diseases in Nigeria: What has happened in the past 20 years?. Nig J Cardiol 2020;17:21-6 |
| Introduction | |  |
Cardiovascular diseases (CVDs) include any disorder, abnormality, or failure to function well, relating to the heart and blood vessels or the circulation.[1] CVDs have been found to be the leading cause of death worldwide over the past decade. In 2013, CVDs caused an estimated 17.3 million deaths and led to 330 million disability-adjusted life years lost.[2] As with many high-income countries during the past century, low-and middle-income countries, including Nigeria, are now-especially over the past two decades-experiencing an accelerating increase in CVD.
The forms of CVDs of interest include hypertension, coronary heart disease (CHD), stroke, hypertensive heart diseases, arrhythmias, heart failure, cardiomyopathies, valvular heart diseases, and congenital heart diseases.
| Trend of Cardiovascular Diseases in Nigeria | | |
The trend in the presentation and management of CVDs in Nigeria is a typical example of the theory of epidemiological transition propagated by Omran,[3] Olshansky and Ault,[4] and Gaziano,[5] as shown in [Table 1].[3],[4],[5],[6] | Table 1: Typical stages of epidemiologic transition in cardiovascular diseases mortality and types
Click here to view |
In the previous 50 years, Nigeria can be said to have been in the first stage, when most of the presentations of cardiovascular conditions were as a result of malnutrition and communicable diseases. Rheumatic heart disease and cardiomyopathies were the major presenting CVDs then.
However, by 1999, Nigeria had progressed through the second and third stages and is currently getting toward stages four and five. At the second and third stages, Nigeria witnessed increases in per capita income and life expectancy. Improvements in the public health systems, with cleaner water supplies, and improved food production and distribution all combined to reduce deaths from infectious disease and malnutrition.
Improvements in medical education and health care delivery, along with other public health changes, contributed to dramatic declines in infectious disease-related mortality rates. Continued improvements in economic circumstances, combined with urbanization and radical changes in the nature of work-related activities, led to dramatic changes in diet, activity levels, and behaviors such as smoking.
Hypertension, rheumatic valvular disease, and cardiomyopathy caused most of the CVDs over the next decade.[7],[8],[9],[10],[11],[12],[13] Few cases of CHD were reported during this period.[14],[15]
Between 1999 and 2000, most publications reflected the new importance attached to hypertension and heart failure as increasing CVD problems with a view to characterizing these conditions as well as the risk/prognostic factors.
While some publications looked at the clinical correlates of hypertension and related complications,[16],[17],[18] some examined the impact of lipids and lipoproteins in hypertension.[19],[20] Some authors assessed investigative modalities, especially electrocardiography (ECG)-based[21] investigations, while few echocardiographic-based studies were published as echo was still emerging then as an investigative modality.[7] Medications in hypertension management and other treatment modalities were part of the issues of interest to clinicians and researchers then. Hypertensive Heart Failure was also being described by a few authors who were characterizing the different types and their correlates.[7],[22]
Over the next decade, more cases of heart failure from different primary conditions (mostly hypertension and cardiomyopathy) were reported and characterized.[23],[24] Echocardiography also became more prominent among the routine investigative modalities for CVDs.[25]
This decade (2000–2009) saw treatments once considered advanced now becoming the standard of care with the establishment of emergency medical systems, coronary care units, and widespread use of new diagnostic and therapeutic technologies such as echocardiography, cardiac catheterization, percutaneous coronary intervention (PCI), bypass surgery, and implantation of pacemakers and defibrillators.
Advances in drug development had also yielded major benefits on both acute and chronic outcomes. The widespread use of an “old” drug, aspirin, had by this period been shown to reduce the risk of dying of acute or secondary coronary events. Low-cost pharmacologic treatment for hypertension and the development of highly effective cholesterol-lowering drugs such as statins had also begun to make forays into both primary and secondary prevention, by reducing CVD deaths.
Efforts to improve the acute management of myocardial infarction led to the application of lifesaving interventions that include the use of beta-adrenergic blocking agents (beta-blockers), PCI, thrombolytics, statins, and angiotensin-converting enzyme inhibitors.
All these manifested in a change in the areas for emphasis on the management of CVDs in Nigeria. This change also reflected in the pattern of presentation of CVDs in the following decade (2010–2019).
As a result, better characterization of the major CVDs was embarked on, with the review of treatment protocols and medications (especially for hypertension and its complications).[26],[27],[28],[29],[30],[31] Protocols for the modifications of risk factors were incorporated in care.[32],[33],[34]
Furthermore, noted in this decade, was an increased prominence of cardiac arrhythmias.[35] Previously scarce conditions such as CHD and pericardial diseases as well as valvular heart diseases became more prevalent,[36],[37] with congenital heart diseases becoming more prevalent, probably from increased awareness.[38] Cardiac surgical interventions also became more available with more presentations requiring surgery.[39],[40]
Different prevalence studies in Nigeria have shown variation as regards the pattern and profile of CVDs in Nigeria. Thus, CVD over the past 20 years in Nigeria can be categorized as:
- CVD with increasing prevalence
- CVD with steady prevalence
- CVD with decreasing prevalence.
Cardiovascular diseases with increasing prevalence
The World Health Organization (WHO) in 2016 revealed that in Nigeria, noncommunicable diseases were estimated to account for 29% of all deaths, of which CVDs contributed 11%.[41] CVDs which have been found to be on the increase over the past 20 years in Nigeria include hypertension, heart failure, and stroke.
A marked increase in the prevalence of CVD of 150% was reported by Adedapo,[42] in South-West Nigeria, and this finding tallies with a study by Ifeoma et al.:[43] High prevalence and low awareness of hypertension in a market population in Enugu, Nigeria. An increased trend in the prevalence of hypertension was also observed in urban Nigeria by several other studies.[44],[45]
A study in South-West Nigeria by Adedoyin and Adesoye showed that out of all the patients presenting with CVDs over a 4-year period, heart failure had the highest occurrence.[46]
Cardiovascular diseases with steady prevalence
Ischemic heart diseases and cardiomyopathies were still found to contribute <1% of CVD burden in Nigeria[47] during the period under review. However, CHD is still relatively increasing in prevalence.[47]
Cardiovascular diseases with decreasing prevalence
Adult congenital heart diseases have been found to have a sustained decreasing prevalence over the past 20 years in Nigeria. This has been alluded to a number of factors which include:
- Improvement and advancement in medical awareness which prompts the early presentation to hospital in younger age groups leading to early intervention and correction before adulthood
- Enlarging the scope of cardiovascular expertise in Nigeria, leading to more erudite professionals being produced yearly, who help in the correct management of childhood congenital heart diseases
- Early detection and intervention made possible by the use of more recent and readily available investigation tools such as ECG and echocardiography
- Contribution of nonprofit organizations and charity foundations who inaugurated and sponsored many open-heart surgeries across the country both for children and adults for example, save a heart foundation, POBIC Foundation, VOOM Foundation, and Kanu Nwankwo Heart Foundation
- Most of these patients with adult congenital heart diseases present in heart failure, thus are usually, though erroneously, classified under “heart failure patients” not “congenital heart disease patients.”
| Incriminating Risk Factors for the Rising Trend of Cardiovascular Disease in Nigeria | | |
Some risk factors are responsible for this rising trend of CVDs in Nigeria. These can be classified as modifiable risk factors, nonmodifiable risk factors, and emerging risk factors.
Worldwide, CVDs are largely driven by modifiable risk factors. In Nigeria, these modifiable risk factors were listed by the WHO (in 2016)[41] in the order of occurrence. These lists include the harmful use of alcohol (22%), physical inactivity (22%), tobacco use (11%), hypertension/raised blood pressure (18%), salt/sodium intake (8%), diabetes mellitus and dyslipidemia (4%), obesity (4%), ambient air pollution (1%), and household pollution (<1%).
On the other hand, the nonmodifiable risk factors include advancing age, male sex, family history of premature cardiovascular events, and race.[48]
Emerging risk factors include elevated homocysteine, small, dense lipoprotein (Lpa), plasminogen activator inhibitor, inflammatory markers such as C-reactive protein and infectious agents-like chlamydia.[48]
| Nigerian Economic Space Interplay on Cardiovascular Diseases | | |
The economic state of Nigeria has definitely impacted on the pattern of CVDs in Nigeria. Health is not cheap. Neither is cardiovascular health. The new developments in cardiovascular health – investigative modalities, medications, interventions available, and other treatment options – all come at a price: A costly price for most Nigerians.
The world bank also noted the poverty headcount ratio at $1.90 a day (2011) to be 53.5% (both in 2003 and 2009) (% of population) [Chart 1].[49] The economic situation of the Nigerian populace means many Nigerians are unable to access nor afford cardiovascular and other health-care services. Thus, there is a plateau effect in the transition as infectious diseases and malnutrition/undernutrition are still contributing to the pattern of CVDs in Nigeria.
The lack of centralized government backup or interventions to enable citizens access healthcare, and the incompetence of the national health insurance scheme in bridging the divide has made the situation more difficult for ordinary Nigerians. The Nigerian budgetary allocation to the health sector has remained poor with <4% of the nation's annual budget being allocated to the health sector. As a result, health care funding of the Nigerian health care sector is majorly from foreign donors.
Corruption in the health system has contributed markedly to the misappropriation of the meager resources available to the health sector. Cardiovascular health care is not exempt from this ill-fated plague!
| Conclusion | | |
Research work on the prevalence of CVD in Nigeria is scanty; however, the available data have shown that there is a general increase in cardiovascular deaths, especially in urban populace.
The factors responsible for this trend include increasing prevalence of CHD risk factors, urbanization, and adoption of the Western diet and lifestyle.
There is a need for increased awareness and education of the general population on the prevention and control of risk factors and training of health professionals on appropriate diagnosis and management of CVDs.
Nongovernment organizations (such as the rotary club.), some religious bodies, and many volunteer agencies such as the VOOM Foundation and Save a Heart Foundation have been of immense help in helping Nigerians access cardiovascular and other healthcare either free of charge or at highly subsidized rates.
There is increasing involvement of willing foreign partners and collaborators as well as Nigerian cardiovascular physicians and surgeons in diaspora in ameliorating the burden of CVDs through grants, periodic outreach missions, donation of both equipment, and consumables.[50]
Acknowledgment
The authors would like to thank Dr. Adaobi Ikemeh.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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