Factors Associated with Anemia Status Among Children Aged 6–59 months in Ghana, 2003–2014

What is Already Known on This Subject? Existing literature using GDHS data shows there are child, household, and sociocultural factors associated with anemia in Ghana. What This Study Adds? This is the first article, that we know of, to assess predictors of anemia in Ghana over three rounds of GDHS data. Younger child age, fever in the last 2 weeks, lower household wealth, less maternal education, and maternal anemia were significantly associated with severe–moderate anemia among children in 2014. The predictors remained relatively constant over time, with similar risk factors being seen in 2003 and 2008. These results can inform policy makers in Ghana.

Globally, undernutrition is one of the largest contributors to child mortality, causing an estimated 45% of total deaths of children younger than five years (Black et al. 2013). Undernutrition encompasses a broad range of public health problems, including deficiencies of micronutrients, especially iron (WHO 2008a), that often contribute to anemia. Anemia is of particular concern in children because it can cause deficits in cognitive and behavioral development and function (Beard and Connor 2003; McCann and Ames 2007). Understanding the complex etiologies of various types of anemia is of particular importance, due to the high prevalence of anemia in many parts of the world. One 2011 estimate indicated that 43% of children under 5 years old had anemia worldwide, with prevalence as high as 71% in parts of central and western Africa (Stevens et al. 2013).

Because of its large contribution to morbidity and mortality, anemia remains an important public health problem, especially in sub-Saharan Africa. In 2008, 78% of Ghanaian under-five children were anemic, with 56% of these children suffering from severe or moderate anemia (Ewusie et al. 2014). Due to this high prevalence, improved understanding of associated factors is needed to better tailor interventions for reducing the burden of anemia in Ghana.

On a biological level, anemia is usually caused by decreased erythrocyte production or increased erythrocyte loss (Camaschella 2015). In addition to such biological causes, there are many complex, upstream environmental, behavioral and social factors that contribute to risk for anemia, especially in children (Balarajan et al. 2011; Siekmans et al. 2014). These factors are often divided into three major categories. First, there are immediate causes, which include inadequate nutrient and absorption (i.e. nutrient supplementation) and exposure to infectious disease (i.e. fever, malaria, intestinal parasites) (Mueller et al. 2017; Paganini and Zimmermann 2017). Secondly, there are underlying causes at the household/family level, such as access to water and sanitation, availability of health services, childcare practice (e.g. breastfeeding) access to diverse food sources, use of insecticide-treated bednets (ITNs), and knowledge about anemia prevention (Larsen et al. 2017). Lastly, the most distal causes are related to the larger sociocultural context, such as education, wealth, and cultural norms and behavior (Ngnie-Teta et al. 2009). Figure 1 provides a graphical depiction of these hypothesized relationships and more information can be found in the methods section. An updated analysis of the relationship between such risk factors and anemia in a nationally representative sample of Ghanaian children is needed given that most existing studies are limited in some way. Investigations into anemia in Ghana generally have involved small sample sizes, and only evaluated risk within small areas (Egbi et al. 2014; Klinkenberg et al. 2006; VanBuskirk et al. 2014). Other studies that used a nationally representative sample are limited by only considering prevalence estimates for anemia or a sample subset of potential predictors (Ewusie et al. 2014; Saaka and Galaa 2017).

The objective of our study, therefore, was to determine the prevalence and predictors of anemia among Ghanaian children aged 6–59 months using nationally representative samples from the Ghana Demographic and Health Survey (GDHS), covering 2003, 2008, and 2014. Thereby, we undertook a more in-depth analyses of anemia risk that also evaluated whether and how there may have been changes in anemia prevalence and correlates over time. We hypothesized many previously identified predictors of childhood anemia, such as malaria and diarrheal disease, would be associated with anemia, as would maternal factors including education and maternal autonomy (Balarajan et al. 2011; Siekmans et al. 2014). In addition, we hypothesized there would be decreasing anemia prevalence over time commensurate with improvements in equity across various socioeconomic and demographic groups.

This study was exempt from ethical approval because it was limited to publicly available datasets that contained no personally identifiable information. All participants provided informed consent to the GDHS interviewers before being enrolled into the study.

Anemia prevalence in Ghana is exceptionally high. Globally, anemia prevalence in young children (6–59 months old) is estimated at 43% as compared with 67% in Ghana (Stevens et al. 2013). From our analysis, ~ 40% of Ghanaian children aged 6–59 months had severe–moderate anemia in 2014. Although this represents a substantial improvement over 2003 and 2008, there is evidence of widening disparities across regions of Ghana. In 2003, severe–moderate anemia prevalence difference was 23% between the highest (Northern region) and the lowest (Greater Accra region). However, that gap increased to 34% in 2008 and 32% in 2014. There was also an urban–rural disparity in severe–moderate anemia prevalence (17% higher in rural areas in 2014), but this disparity has remained relatively constant over time.

Across all three survey years, child’s age was negatively associated with severe–moderate anemia, as older children had lower odds of anemia than younger children. The high prevalence of severe–moderate anemia in children under 2 years old appears related to poor maternal nutrition, as children born to malnourished mothers have poor stores of many essential micronutrients, such as iron, zinc, vitamin A and B₁₂ and folate (Kotecha 2011; Neumann et al. 2004). Our finding that children with mothers who have anemia have higher odds of developing anemia themselves, provides further evidence for this (Table 5).

Complementary foods and feeding practices are especially important for determining the micronutrient adequacy of 6–23 month-old children, as breast milk makes a progressively smaller contribution to an infant’s nutritional requirements into late infancy and early childhood (Saaka and Galaa 2017; Woldie et al. 2015). Our findings are consistent with this observation, in that the prevalence of severe–moderate anemia was higher among children who were still being breastfed than those who never or formerly breastfed (Tables 2, 3, 4). This likely reflects inadequate consumption of high quality complementary foods with continued breastfeeding rather than a deleterious effect of continued breastfeeding itself on iron status or anemia (Cumber et al. 2017; Lander et al. 2009). Reverse causality may also underlie this association (i.e., smaller, malnourished children may be weaned later because of perceived vulnerability) (Habicht 2000; Simondon et al. 2001).

Infants also generally have a higher incidence of infectious diseases, which can reduce their ability to ingest and absorb iron, perhaps further explaining the higher prevalence of anemia among younger children (Villalpando et al. 2003). From bivariate analyses across all years, we determined that a higher prevalence of anemia was associated with diarrhea or fever experienced within the previous 2 weeks (Tables 2, 3, 4). Although diarrhea and fever were associated with anemia, the cross-sectional nature of observations precludes determining the direction of the association. Participant-reported diarrhea or fever was asked for a period preceding the Hb measurement, although we cannot determine the temporal pattern of any association. One published prospective study has suggested that anemia may be a precursor of diarrheal disease (Levy et al. 2005). The relationship could also be cyclic, with diarrhea initially decreasing the body's ability to ingest and absorb iron, hence increasing subsequent risk of anemia, and anemia then increasing the risk of additional diarrheal episodes (Semba et al. 2008).

The association between fever in the past 2 weeks and severe–moderate anemia persisted in the multivariable model for all survey years, however, this was not the case for diarrheal illness. In our model, we controlled for both water source and toilet type (often a proxy for sanitation), which could have attenuated any association between diarrheal illness and anemia, as cleaner water and improved sanitation are associated with a lower risk of diarrheal pathogen exposure and illness (WHO 2014). More broadly, socioeconomic status (e.g. household wealth and education) also has been shown to predict health outcomes (Cameron and Williams 2009; Feinstein 1993). We included both household wealth and education in our multivariable models, which could have controlled for the association between two health indicators, such as diarrhea and anemia (see Fig. 1).

In 2003 and 2014, children from higher-income households and children with more highly educated mothers had lower odds of severe–moderate anemia in multivariable analysis. (For 2008, these associations were only significant in bivariate analysis.) It seems reasonable that households with higher incomes are better equipped to keep their children healthy due to a greater ability to purchase health services and food with higher nutritional value. Additionally, highly educated mothers are more likely to be knowledgeable about how to care for their own health, and that of their child.

The prevalence of anemia among children aged 6–59 months in 2014 remains unacceptably high, even though substantial improvement has occurred since 2003. Despite overall advances, Ghana has experienced widening disparities in the prevalence of anemia among regions, and a persistent disparity between urban and rural areas. Results demonstrate that younger child age, fever in the last 2 weeks, lower household wealth, less maternal education, and maternal anemia are significantly associated with greater severe–moderate anemia. Associations have remained relatively consistent over the 2003, 2008 and 2014 time periods. In order to decrease anemia prevalence among children, the Ghanaian government should concentrate on educating women, both through the traditional education system and through antenatal care visits. Antenatal care visits could also provide an opportunity to ensure mothers are receiving adequate nutrition during pregnancy, as this has significant implications for the amount of iron available to infants through breastfeeding. A focus on improving water sources and sanitation in Ghana would also be beneficial, since they are often seen as predictive of diarrheal disease, which may have a cyclic effect on anemia.