Statistics from Altmetric.com
Death from heart failure (HF) in high-income countries is largely a problem of the very elderly with ischaemic heart disease. For example, in Olmsted County, Minnesota in 1991, the mean age of newly diagnosed heart failure patients was around 75 and almost half were over 80 years old.1 Two-thirds of these people had heart failure from coronary atherosclerosis. Vast resources are available to optimise the outcomes for these individuals. In 2010, the USA, with an estimated heart failure prevalence of 2.8%, spent approximately US$24.7 billion on medical care for this condition, almost US$2900 per heart failure patient, or US$80 per capita.2
In stark contrast, heart failure in sub-Saharan Africa is more often a cause of death and suffering among the young due to a more varied set of conditions, of which coronary artery disease is still a very minor contributor. Although the resources applied to address these problems have not been quantified, according to the World Bank, the average per person expenditure on all healthcare in sub-Saharan Africa in 2012 (including middle-income countries) was US$95.3 Accordingly, the amount spent on all healthcare per person in this region was almost the same as the amount spent on heart failure alone in the USA.
Makubi et al4 report on the aetiology, treatment and 6-month outcomes of patients diagnosed with heart failure at Muhimbili National Hospital in Dar es Salaam, Tanzania, between 2012 and 2013. The authors’ findings are striking and consistent with dozens of reports from African referral hospitals since the 1950s: the main aetiologies of heart failure are hypertensive heart disease, cardiomyopathies and rheumatic heart disease (RHD). These findings, as well as the mean patient age of 55 years, are also consistent with a recent continental registry of new heart failure diagnoses from university hospitals in nine African countries.5
This report from Tanzania is among the highest-quality heart failure registries to come from sub-Saharan Africa (SSA) to date, and highlights several issues of great relevance to health policy in this region. Before returning to these larger points, however, this editorial must question the authors’ primary conclusion: that their study ‘discloses a change in the etiologic pattern of HF in SSA, where rheumatic heart disease and cardiomyopathy have previously been dominant.’
While this claim is intended to emphasise the importance of a focus on early detection and treatment of hypertension, it has the unfortunate consequence of minimising the importance of other conditions. The authors’ claim must be questioned for at least two reasons. First, on our review of prior published reports from the same facility (Muhimbili National Hospital), there is actually no clear trend in terms of change in aetiology of heart failure (see table 1). Second, as noted by the authors themselves, they are reporting from an urban referral centre, while Tanzania remains 73% rural.3
Changes in diagnostic modalities over the decades (in particular echocardiography) complicate comparison between cardiovascular series from Tanzania, but it is difficult to argue that there is a straightforward decline in RHD or cardiomyopathy prevalence. While Makene and Muindi did find a higher proportion of RHD relative to hypertensive heart disease in the 1970s, Nhonoli, in the 1960s, found nearly the same proportion of RHD and hypertensive heart disease as Makubi and colleagues, with a lower proportion of cardiomyopathies. In fact, Nhonoli, citing an earlier (now unavailable) report by Cole from the 1950s wrote ‘for the past decade hypertensive heart disease has remained the commonest cardiac condition bringing patients to hospital in Dar es Salaam.’6 ,8
Thus, the most prominent finding from this most recent report from Tanzania is the persistent dearth of ischaemic heart disease relative to high-income countries. Makubi and colleagues are telling a story that is consistent with other heart failure registries from Africa, and one that needs to be better incorporated into the burden of disease estimates for cardiovascular disease in this region, and ultimately into policy prescriptions based on local epidemiology. The Global Burden of Disease Study for 2010, for example, still suggests that ischaemic heart disease accounts for 30% of Disability-adjusted Life Years (DALY) due to cardiovascular disease in Tanzania (as well as sub-Saharan Africa more generally), a result that is seemingly inconsistent with the cardiovascular experience at Muhimbili.9 Similarly, non-communicable disease policy frameworks focused exclusively on global ‘best-buys’, such as tobacco control and statin-based polypills, are unlikely to have much of an impact on the endemic cardiovascular burden driven by hypertension and streptococcal disease rather than emerging pathologies driven by cigarettes and hyperlipidaemia.
Makubi and colleagues highlight the need to address hypertension as a preventable cause of heart failure. In this regard, there is an interesting continuity between the experience in Africa, where hypertension still largely goes untreated, with the experience from the Framingham Heart Study in the USA.10 Prior to the development of effective blood pressure-lowering medications in the 1950s, around 2% of men older than 45 years of age in Framingham had blood pressures in excess of 210/120 mm Hg. At that time, only 2.3% of the population was on antihypertensive treatment. By the 1980s, almost a quarter of men in Framingham were on antihypertensive treatment, and blood pressures over 210/120 mm Hg had been virtually eradicated. The current report from Tanzania should highlight the need to eradicate this kind of malignant pathology from Africa as well.
RHD is still a disturbingly common cause of heart failure in the Tanzanian series related by Makubi and colleagues, accounting for 12% of cases. It is incredible to reflect that 60 years ago on visiting Albert Schweitzer's clinic in Gabon in 1959, the American cardiologist Paul Dudley White and colleagues wrote ‘with our present knowledge of the cause and surgical relief of rheumatic heart disease, we believe strongly that it is a duty to help bring these sufferers the benefits of better penicillin prophylaxis and of cardiac surgery, when indicated. The same responsibility exists for those with correctable congenital cardiovascular defects.’11 These findings highlight the need for more aggressive sore throat management in the community, as well as chronic penicillin prophylaxis and increased access to cardiac surgery so many years later.
Another element of continuity between this study by Makubi and colleagues with the vast majority of prior reports on heart failure from sub-Saharan Africa is the urban context. This bias reflects the concentration of cardiovascular researchers and therapeutic resources for cardiovascular disease at national and regional centres. Sub-Saharan Africa is still 63% rural, however, and the extremely poor in Africa are likely to remain concentrated in rural areas.3 There is a great need for strategies to simplify, decentralize and integrate diagnosis (including echocardiography) and treatment of heart failure at district hospital level in the interest of equity.
Heart failure is a devastating condition, nowhere more so than among the rural poor in sub-Saharan Africa. The full spectrum of effective prevention, treatment, compassionate palliation and social protection is needed. In this regard, it is instructive to look back to some of the first published accounts on heart failure in Africa. The Alsatian medical missionary and theologian Albert Schweitzer wrote from Gabon in 1913 ‘the number of heart complaints astonishes me more and more… I cannot help saying to myself that there is something really glorious in the means which modern medicine has for treating the heart. I give digitalis according to the new French method (daily doses of a tenth of a milligram of digitalin continued for weeks and months) and am more than pleased by the results obtained.’12 Following independence, and the development of much more effective pharmacologic and surgical therapies, African cardiovascular leaders echoed Schweitzer's enthusiasm.
Fortunately, the experience documented at Muhimbili is encouraging for decentralisation of heart failure services to rural areas in Tanzania. First, the continued paucity of regional wall motion abnormalities in this series allows for streamlined training in diagnostic strategies that incorporate echocardiography for internists, paediatricians and mid-level practitioners.13 Second, the medications needed to treat heart failure are all generic and available at low cost if procured appropriately. Finally, the quality of care for heart failure at this centre was quite good, suggesting the hard-won development of a cadre of competent practitioners in Tanzania capable of training, mentoring and supervising lower levels of the health system. Although gaps remain in the appropriate application of anticoagulation, Makubi and colleagues found a very high rate of use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (92%). While the use of β-blockers was lower (42%), this may be appropriate given that 38% of patients had an EF greater than 45%. Although there is much continuity at present for heart failure in Africa, there is a great demand and possibility for change.
Competing interests None.
Provenance and peer review Commissioned; internally peer reviewed.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.