Differentials in prevalence and correlates of metabolic risk factors of non-communicable diseases among women in sub-Saharan Africa: evidence from 33 countries

Non-communicable diseases (NCDs) have recently become a prominent cause of mortality, which accounts for nearly two-third of deaths worldwide, while more than three-quarters of NCD-related mortality occur in resource-constrained settings [1]. In sub-Saharan Africa (SSA), the problem of NCDs and their risk factors are on the increase with several causes which may emerge in individuals as anemia, increased blood lipids and obesity, raised blood glucose, elevated blood pressure amongst others [2–4]. These risk factors have been associated with increased disability or morbidity and mortality. Healthy lifestyles and NCD control were the goals of Global Ministerial Conference, which prepared the platform for the United Nations (UN) Summit on NCD and subsequently, the declaration later in the year 2011 [5]. During the Moscow Declaration on NCDs in 2011, that proceeded from the ministerial conference, encompassed a responsibility from governments to create public policies that give equitable health supporting conditions that make communities, families and individuals to have healthy behaviors, as they give precedence to NCD prevention and control, maintaining other health care objectives and to reinforced the commitment of multiple sectors to address NCDs risk factors such as hypertension, anemia, overweight and obesity.

Obesity and overweight are prominent determinants of metabolic disorders including hypertension, diabetes, cancer and cardiovascular diseases [6–8]. An increase in overweight and obesity due to sedentary lifestyles or physical inactivity and feeding pattern specifically highly processed diet has affected community health in an unprecedented manner, by contributing to the risk of metabolic and cardiovascular diseases [9]. Similarly, several social, economic and demographic changes have occurred in resource-constrained settings; such as industrialization and urbanization which has influenced the lifestyles of people in developing countries in the past few decades. Obesity and overweight are major public health issues, particularly among women [4]. The effects of obesity and overweight on the sexual and reproductive life of women are more critical, especially during pregnancy. Sharp changes have been observed in many countries in Africa which are currently confronted with obesity and overweight among women, together with large increase in the occurrence of NCDs [10]. Evidence has revealed that women had approximately double the obesity prevalence of men [4]. Consequently, the problem of obesity and overweight among women is increasing at a rapid rate in developing countries including sub-Saharan Africa region. However, in multi-country studies, the prevalence of overweight and obesity is higher in urban areas than in rural areas of developing countries [4, 7].

Over the past decades, the prevalence of hypertension has been on the rise, from estimated 600 million in 1980 to approximately 1 billion in 2010 due to population growth, ageing and lifestyle [11]. The problem of hypertension and other prevalent NCDs has continued unabated in recent years, and it is the key risk factor for numerous cardiovascular diseases [2, 12]. Recent study reported that the prevalence of hypertension in African most populous country formed a crucial proportion of the total burden in Africa due to large population presently estimated over 170 million [2]. Considering a region with constrained health-care resources, the dynamic disease burden brings issues for health care providers, policy makers and progress toward achieving developmental goals [10]. Hypertension in sub-Saharan Africa has been associated with numerous factors including urbanization, lifestyles, diets, socio-economic status and physical inactivity [13–16].

NCDs is attributable to numerous risk factors including anemia, which is a prominent nutritional deficiency problem affecting women [17], and a risk factor for poor pregnancy outcome leading to problems that affect the life of foetus and mother alike [17, 18]. Anemia is an age-long public-health problem, particularly among the disadvantaged population in developing countries [19–21]. The prevalence of anemia is a vital health indicator for the measurements of maternal health outcomes [20]. Study on the magnitude of anemia and its determinants in vulnerable groups, such as women of reproductive age is essential for evidence-based intervention modalities, particularly in developing countries, where women suffer from micronutrient deficiencies and shortage of food [21]. The majority of women in resource-constrained settings are at higher risk of anemia due to increased level of macronutrient deficiencies, dietary iron deficiency and infections such as malaria and hookworm infestation amongst others [22]. Anemia has remained more prevalent among women in developing countries [3], while lactating mothers are most prone to blood loss during childbirth and maternal iron depletion [21].

Based on the worrisome prevalence in hypertension, anemia, overweight and obesity, and the possible increase in chronic diseases in sub-Saharan Africa countries, data on the correlates of the risk factors of NCDs is crucial and urgently needed to inform policy and programme interventions to address the problem in Africa. Evidence-based information on the prevalence and correlates of hypertension, anemia, overweight and obesity is paramount to understand the size of the problem, identify key population and develop effective intervention. Notably, a number of studies that examined hypertension, anemia, overweight and obesity prevalence in Africa centered on single country. However, the present study explored the prevalence and correlates of metabolic risk factors of NCDs in several sub-Saharan Africa countries and organized the results to aid understanding.

The description of high blood pressure (HBP), anemia and anomalous body mass index (BMI) by countries in sub-Saharan Africa was presented in Table 1. Notably, only 5 countries in sub-Saharan Africa region reported data on blood pressure, which include; Benin, Burundi, Ghana, Kenya and Lesotho. The percentage of HBP was highest among women in Lesotho with about 17.3% and lowest among women in Burundi (1.0%). More so, the results showed that anemia is prevalent among sub-Saharan Africa women; where more than half of the women from Gabon (60.6%), Gambia (59.0%), Senegal (54.3%), Congo (54.2%), Mozambique (54.0%), Cote d’Ivoire (53.7%) and Mali (51.4%) were reportedly anemic. However, Rwanda (19.2), Namibia (20.7%) and Ethiopia (23.6%) had the least anemic women. Further, Madagascar (25.5%), Ethiopia (21.1%), Senegal (20.8%), Chad (18.0%) and Burundi (17.7%) reported the highest underweight women, while Lesotho (4.1%) had the lowest percentage of underweight women. In addition, Gabon (26.1%), Comoros (25.4%), Ghana (25.1%), Zimbabwe (23.4%), Sao Tome & Principe (23.2%), Kenya (22.7%), Cameroon (22.1%) and Benin (20.3%) had the leading overweight women and Madagascar (5.2%) had the minimum overweight women in sub-Saharan Africa countries. The percentage of obesity in sub-Saharan Africa showed that Lesotho (19.9%), Gabon (18.9%) and Ghana (15.6%) were the prominent countries with obese women, while Madagascar (1.1%) had the minimum obese women (See details in Table 1).

In this study, we extensively explored the prevalence of prominent risk factors of NCDs which include hypertension, anemia, underweight, overweight and obesity among women of reproductive age in sub-Sahara Africa countries. Furthermore, we investigated the correlates of the risk factors of NCDs with the aim of understanding the pattern of the problem and how best to prevent and control it. The findings of this study revealed that a large number of women in sub-Sahara Africa countries have suffered from hypertension, anemia, underweight, overweight and obesity. The most striking findings in our study were the very high prevalence in hypertension, anemia, underweight, overweight and obesity among women of reproductive age in sub-Sahara Africa countries. These findings are similar to the reports from previous studies in developing countries [2, 4, 22, 26, 27].

This study revealed that living in rural residence, smoking and alcohol consumption were associated with reduction in the risk of overweight and obesity. Conversely, high consumption of fruits and vegetables were positively associated with overweight and obesity. In addition, higher number of children ever born, older age, involvement in marriage or living with a partner, women’s employment, high socio-economic status such as wealth index and education were also associated with higher risk of overweight and obesity. Our findings were consistent with the results of previous studies on the factors associated overweight and obesity [8, 9, 28]. The increase in the risk of overweight and obesity among women who are employed, have formal education and higher wealth index showed that as the economy and individuals income improve, they tend to have sedentary lifestyles, reducing their physical activity levels. Urbanization and adoption of Western lifestyles could also contribute to dietary shift to inappropriate food choices such as frequent intake of “fast foods” including sugar and fat leading to increase in body weight [29]. More so, the impact of marriage on overweight and obesity could be as a result of women’s sexual and reproductive activities such as child bearing with increase in sedentary lifestyles. The content of alcohol or “hot drinks” and nicotine obtain from smoking, especially for heavy users could be responsible for the breakdown of body cells leading to reduction in the risk of overweight and obesity as found in this study [30, 31]. Notwithstanding, smoking and alcohol consumption are known to have negative long-term health effect to the body.

Consumption of fruits, vegetables and rural residence were significantly associated with reduction in the odds of hypertension among women in sub-Saharan Africa. This findings is similar to previous report [32]. The factors associated with increase in the odds of hypertension were; high body mass index, smoking, large number of children ever born, high wealth index, marriage or living with a partner, education and older age. Similar findings have been made by previous studies in developing countries [10, 12, 26, 32]. Reduction in the risk of hypertension among rural dwellers could be due to differences in life styles such as dietary patterns and physical activity. Fruits and vegetables contain micronutrients and vitamins that aid metabolic activities of the body and also help in body circulatory system [33, 34]. More so, the association between older age and increased risk of hypertension could be due to the biological effect of increased arterial resistance as a result of arterial thickening as one grows older [35, 36]. In addition, our findings of overweight and obesity as factors of hypertension agree with the general view that adiposity is linked to hypertension [37–39]. The associations between hypertension and metabolic, socio-demographic, economic and behavioural factors revealed epidemiological transition in resource-constrained settings usually explained by economic development leading to urbanization with increased sedentary life style, deviations in dietary habits, social stress and smoking. Sub-Saharan Africa countries are likely to be undergoing similar development.

Socio-economic status of women was significantly associated with anemia among women. Women from rural residence, high number of children ever born, married and those from lower socio-economic class had higher odds of anemia. The findings of this study is consistent with previous results [17, 40]. Other studies have argued that the association between the place residence and health problems in developing countries is driven mainly by higher individual-level and community-level socioeconomic status. These findings could also be due to those women from lower socio-economic status lack the finance to purchase quality food as well as sufficient quantity of foods for proper feeding. The results also showed that fruits consumption does not help to cure anemia. However, high body mass index was associated with reduction in the odds of anemia among women in sub-Saharan Africa. It is possible the women with high body mass index are usually among the well-off and those in the advantaged group, who are able to afford quality and adequate food for proper feeding [17, 40].

The goal of this study was to explore the prevalence and correlates of the risk factors of NCDs in sub-Sahara Africa region. In presenting an evidence-based context for government and other health policy makers on the strategies to reduce this burden in low-resource settings, detailed up-to-date information on the metabolic risk factors of non-communicable diseases has been provided in order to match this with available resources. A major strategy to prevent or control the occurrence of NCDs is to focus on reducing anemia, hypertension, overweight and obesity.

Interventions that focus on the modifiable determinants of overweight and obesity can help to prevent the increasing burden of non-communicable disease in sub-Saharan Africa. Hence, future obesity prevention programmes in resource-constrained transitioning settings will need to foremost, consider the family level with a target on well-off women. Development of community-based programmes influencing dietary patterns, physical activity, alcohol use and smoking, behavior change communication about the effect of hypertension, anemia and high body mass index, could help to reduce chronic disease associated with the metabolic risk factors of non-communicable diseases. This will also involve a multi-dimensional strategy and will require intervention at the individual and population levels. Health policy makers and government need to focus on widespread interventions through community health extension programmes.