1. Introduction
Cardiovascular diseases are the leading cause of death worldwide. They are responsible for approximately 17.5 million deaths annually, representing 31% of total global mortality [2]. More than three-quarters of these deaths occur in low- and middle-income countries [2]. In Côte d’Ivoire, of the 31% of deaths attributed to non-communicable diseases, 11% are related to cardiovascular diseases, making them one of the leading causes of death [3].
Cardiovascular diseases are responsible for 51% of deaths among women in Europe and 30% in France [4]. They lead to numerous complications, including heart failure. This public health problem is all the more concerning as incidence and mortality are increasing among younger women [5].
In sub-Saharan Africa, heart failure has become a major cardiovascular disease with significant socio-economic consequences due to its high prevalence, high mortality, and impact on younger generations [6]. In African hospital series, its prevalence varies from 25.6% to 45.9% [6], with heart failure with reduced ejection fraction being the most frequent form.
In Côte d’Ivoire, a study carried out in 2017 at the Abidjan Cardiology Institute and the National Police Hospital by Djinguin et al. on 989 admitted patients, heart failure represented 60% to 65% of cases with an average age of 55 ± 12 years [7].
Some studies highlight relevant sex-related differences in patients with heart failure. These differences are found in pathophysiology, etiologies, and prognosis [8][9].
Both men and women are at risk of developing heart failure secondary to all known heart conditions. However, some causes are more common in women: hypertension, thyroid dysfunction, diabetes, obesity, valvular heart disease, and a predisposition to myocardial ischemia [10]. Although women represent a significant proportion of the growing heart failure epidemic in the West, they are underrepresented in clinical trials, despite epidemiological data revealing high prevalence and impact.
Few studies have focused on heart failure in women in sub-Saharan Africa, particularly in Ivory Coast.
Hence the importance of this work, the objective of which was to describe the characteristics of heart failure in women in order to contribute to the improvement of therapeutic management.
4. Discussion
The large size of our sample allowed us to obtain high statistical power for the tests performed, thus increasing the likelihood of detecting significant differences in women with heart failure in our setting. However, the main limitations of our study were as follows: the retrospective data collection resulted in a significant number of missing data points, and the available data in the literature on this topic are insufficient and remain highly controversial.
In our series, the hospitalization rate for women with heart failure was 48.2%. Our results are close to those of Karaye et al. in Nigeria and Makubi et al. in Tanzania, who observed rates of 44.3% [11] and 51% [12], respectively. In contrast, in European hospital registries, Steven M et al. found a rate of 38% [13] among women with heart failure. This discrepancy could be explained by delays in care and financial constraints limiting access to treatment in our regions.
The mean age of women with heart failure was 51.5 years ± 18.9 years. Our results are similar to those of the THESUS study (50.7 years) [14]. In contrast, European and North American studies reported mean ages of 73.1 and 75.1 years, respectively. This difference could be related to lower life expectancy in sub-Saharan Africa, but primarily to the lack of access, for the majority of the population, to healthcare facilities that allow for early detection and effective management of the various cardiovascular risk factors contributing to the development of heart failure.
The most represented age groups were those of [20 - 40] and [60 - 80] years.
The 20 - 40 age group is the one in which peripartum cardiomyopathy is most frequently observed, as shown by studies by Pio in Togo [15], Codjo in Benin [16] and Karaye in Nigeria [11]. This cardiomyopathy mainly affects young women from disadvantaged socioeconomic backgrounds who have already had several pregnancies.
As for the age group between [60 - 80] years, it contradicts the results obtained in developed countries.
Most of the women resided in urban areas (96.6%), particularly in Abidjan, and almost all were housewives. This could be explained, on the one hand, by the presence of the Cardiology Institute in Abidjan, and on the other hand, by the epidemiological evolution of cardiovascular diseases, linked to rapid urbanization and changes in lifestyle, diet and cultural attitudes, as well as the emergence of certain factors known as “cardiovascular risk factors”.
This study revealed that universal health insurance, though essential for an increasingly impoverished population, has not yet been widely adopted since its launch on April 25, 2017, in Côte d’Ivoire. The vast majority of patients (over 82.2%) have no health coverage. This lack of coverage further limits access to quality care.
The majority of patients were married (43.2% of cases). Our results are similar to those in the literature, which report a higher proportion (88%). This could be explained by the presence of certain factors in women, such as chronic stress and negative emotions like anxiety, anger, and hostility stemming from marital problems in our setting.
Hypertension was present in 53% of women with heart failure. Our results are similar to those of the THESUS study, which found a 51% prevalence of hypertension in women. This could be explained by a greater vulnerability to hypertension in people of African descent.
The combination of hypertension and diabetes increases the risk of death.
In several African studies, diabetes appears as the second leading cardiovascular risk factor after hypertension. Its prevalence was 20.4% in our study, a figure close to that observed by Pio M in Togo (24%) [15]. Multicenter African data and literature reviews have highlighted varying prevalences of diabetes in women with heart failure, ranging from 11% to 59%. This high prevalence of diabetes in these women is likely linked to its alarming proportions worldwide. Analysis of data from the Framingham study, which initially demonstrated a marked increase in the risk of heart failure in people with diabetes, revealed that this risk was 2 to 5 times higher than in non-diabetics [17]. Further research is needed to understand the mechanisms underlying this increased risk of heart failure associated with diabetes in women. Once considered problems specific to high-income countries.
The hormonal changes occurring during menopause lead to a true metabolic and vascular syndrome, with an increase in cardiovascular risk factors. Sex also influences the diagnosis of cardiovascular diseases, as healthcare professionals often fail to consider gynecological and obstetric history as emerging risk factors. These societal biases result in missed opportunities, sometimes with serious consequences, particularly for women in precarious situations who lack access to care [17][18].
A genuine awareness of the specificities of cardiovascular risk in women led to a red alert in the late 1990s in the United States, with the decennial review of the “Go Red For Women” program led by Lori Mosca, including recommendations for care. At the same time, Peter Collin [19].
It has been recommended that gynecological and cardiological care pathways be implemented at menopause [19]. In Europe, Angola Mass emphasized the urgency of implementing the ambitious Women’s Cardiology Program. It published a “Gynecocardiology Handbook” on cardiovascular diseases in women. More recently, the American societies of cardiology and gynecology have stressed the need for comprehensive women’s care, with the gynecologist finally being recognized as a key player in primary care and cardiovascular screening [19].
At the clinic, more than half of the women admitted were at NYHA stage IV, representing 55.1% of cases. Our results are lower than those of Coulibaly et al. [20], who observed 73.6% of cases. However, they are ten times higher than those of the THESUS study (2.9%) [14].
Heart failure was the most frequently observed condition in sub-Saharan Africa. In our context, poverty, delayed medical consultations, lack of access to care, and the use of non-pharmacological therapies could explain this progression towards particularly severe forms of the disease.
Most women had de novo heart failure and an average number of episodes of heart failure of 1.5 ± 0.8. The duration of heart failure in women does not appear to have a real impact on hospitalizations.
The main factors contributing to decompensation are bronchopulmonary infections and poor treatment adherence. Influenza and pneumococcal vaccination for heart failure patients, recommended by the European Society of Cardiology, appears difficult to implement in our regions due to its cost and a lack of patient awareness. The reliance on traditional medicine and the low level of patient education in sub-Saharan Africa explain these disparities in care. This observation underscores the need to implement a patient education program in our hospitals, which could improve treatment adherence.
In sub-Saharan Africa, several authors have identified hypertensive heart disease as the main cause of heart failure. In our series, it accounted for 35.1% of cases. Our results were higher than those of Coulibaly (28.9%) [21], but lower than those of Soweto (61%) [14].
We believe it is important to prioritize local campaigns in addition to media. We can rely on traditional leaders or introduce the concept of cardiovascular risk factors from primary school onwards, alongside the teaching of communicable and infectious diseases.
Dilated cardiomyopathy (DCM) is one of the most common forms of heart disease in sub-Saharan Africa [14]. It is a serious condition with a poor prognosis, characterized by high mortality, ranging from 15% to 50% [22]. In our series, DCM (19%) was the second leading cause of heart failure after hypertensive heart disease. In Europe, DCM accounts for 20% to 50% of hospitalizations for heart failure after ischemic heart disease. In our study, as in other African series, the patients were relatively young, with a mean age of approximately 50 years [23][24], compared to Western series where patients were often older due to the longer life expectancy in that region of the world [25].
Perinatal cardiomyopathy, meanwhile, represents the third leading cause of heart failure in women, as it is a mysterious pathology that occurs during the perinatal period due to inflammatory and immunological disorders and oxidative stress triggered during this phase of pregnancy.
Valvular heart disease accounted for 13% of cases in our series. This result could be explained by the relative decline in rheumatic valvular heart disease, attributable to the widespread use of antibiotics and improved lifestyle habits.
Regarding paraclinical characteristics, most women presented with cardiomegaly on chest X-ray (98.8% in our series). This could be explained by the almost systematic presence of cardiomegaly related to the advanced stage of the disease before admission.
Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and accounts for one-third of hospitalizations for arrhythmia in Western countries [26]. In our series, it was responsible for 43.2% of cases. Our results are similar to those of Coulibaly I et al. in Côte d’Ivoire, who observed a proportion of 48% [27]. The proportion of AF in patients with heart failure varies from 10% to 30% [28]. This could be explained by the clear predominance of rheumatic valvular heart disease, which very often manifests as heart failure and remains common in developing countries. AF is both a cause and a consequence.
LVH (60.6%) is the most frequently found morphological abnormality on the electrocardiogram in our patients and in the literature.
Heart failure with acute exacerbations remained common (61.4%) in our population. This phenomenon could be linked to a significant increase in cardiovascular risk factors associated with urbanization and lifestyle changes. Other factors contributing to the high proportion of heart failure in women include poverty, which explains delays in seeking medical attention and difficulties accessing care; a lack of awareness of the early signs of heart failure; ignorance; abandonment of conventional treatments and recourse to traditional medicine, prayer, and, sometimes, care provided by unqualified first aiders.
Anemia (common and multifactorial in heart failure) is a poor prognostic factor at all stages of the disease. However, its prevalence in heart failure varies across studies. In women with heart failure, anemia appears to be most often associated with renal insufficiency. This renal insufficiency may result from nephroangiosclerosis, in addition to long-standing, uncontrolled hypertension. Severe renal insufficiency in these patients increases the risk of cardiovascular complications through structural changes in the myocardium, and the anemia may be related to decreased erythropoietin synthesis by the kidneys.
From a biological point of view, BNP and NT-proBNP are the most powerful and widely used prognostic biomarkers in heart failure; they reflect elevated filling pressures and the degree of ventricular dilation.
Regarding treatment, 93.3% of the women in our study received furosemide. This rate is close to the 90% reported by Kingue [29], but higher than the 32.64% reported by Falase [10]. This could be explained by the clinical stage of the disease, with sodium and water retention. Angiotensin-converting enzyme (ACE) inhibitors were used in 83.3% of cases; our results are higher than the 64.7% reported by Kingue [29] and the 61.3% reported by Flather [30]. The rate of beta-blocker use in our study was 71.9%, close to the 78.3% reported by an American study [31] and significantly higher than the 19.8% reported by Kingue [29]. This could be explained by the age of Kingue’s study [29], which dates back more than 10 years. These varied observations could be explained by the practitioners’ good adherence to European recommendations for the management of heart failure. This management is not exclusively pharmacological; non-pharmacological aspects of treatment are indeed addressed before any medication is administered. Thus, in our study, non-pharmacological treatment was interventional in 9.3% of cases, surgical in 4.7% of cases, and electrical in 5.5% of cases.
However, any surgical indication, whether it be coronary revascularization or valvular surgery, is based on an analysis of the benefit/risk ratio of the operation.