This study aimed to examine the spatial distributions of four forms of malnutrition; severely thin, underweight, overweight and obesity, among women of reproductive age-group in Nepal. It explored a complete understanding of covariates' effects on different categories of malnutrition among women using a Bayesian geoadditive quantile regression method. The study used data from a nationally representative survey to assess different forms of malnutrition as per the WHO recommended cut-offs criteria: severely thin (< 16 kg/m2) underweight (< 18.5 kg/m2), overweight (> 25 kg/m2) and obese (> 30 kg/m2) [26]. Several earlier studies that investigated underweight and overweight/obesity among adult men and women population in Nepal used the conventional logistic regression analysis [27,28], thus limiting to convey evidence beyond prevalence and associated risk factors of malnutrition. Using a Bayesian geoadditive quantile regression technique this study explored the effects of covariates on different forms of malnutrition associated with different quantiles of BMI [17]. To overcome the limitations of earlier studies, we fitted spatial effects across provinces and nonlinear smoothing effects of women's age to provide a complete picture of malnutrition simultaneously controlling for several covariates under study. Interestingly, our study reported that women in Nepal face a double burden of malnutrition, as suggested by the spatial effects. Based on the analysis of nonlinear effects, an apparent nonlinear relationship was observed between the effects of women's age and under- and over-nutrition.
We included women as our study population, keeping in mind that women in the LMICs are at higher risk of undernutrition. Studies from Nepal [27], and from other south Asian countries, including Bangladesh [22], and Pakistan [29] corroborated a high prevalence of poor nutritional status among women than compared to males. Despite concerted programmatic interventions aiming at improving the nutritional status of women, this has always been a challenge in Nepal. Rural women are more prone to underweight due to several underlying factors such as poverty and inequity that influence dietary patterns, including low dietary diversity and food insecurity [30]. The undernutrition (BMI < 18.5 kg/m2) status of women of reproductive ages slightly declined over the past decade. Though the decline is not uniform across the country and ubiquitous inequities exist across provinces [19,31].
Similarly, the spatial effect demonstrated that women from provinces 2, 5, and Sudurpaschim were more likely to be undernourished. Women in Bagmati and Gandaki had a higher likelihood of being overweight and/or obese. These heterogeneous findings across provinces are supported by a study that involved geospatial analyses revealing a higher likelihood of women to be overweight and obese in Bagmati and Gandaki [32]. Notably, these are wealthier provinces and constitute many affluent cities and districts having high Human Development Index. Contrarily, most of the districts in provinces 2 and Sudurpashchim lag behind in achieving targets of health indicators due to the high prevalence of poverty, low education attainment, socio-cultural norms and practices affecting healthcare seeking behaviours, and inequalities in health service utilization [33]. Hence, women in these regions are more vulnerable to nutritional deficiencies due to these factors contributing to higher undernutrition. It infers that women in these provinces need urgent nutrition support programs to intervene in the aggravating situation of undernutrition.
Undernutrition among women is in a declining trend, and overweight and obesity, on the other hand, are rising among urban residents. Our study findings indicated that women from urban areas were more likely to be obese. A study conducted in Nepal using STEPS data revealed a significant association between high BMI among urban residents implying that the nation is amid a double burden of under- and over-nutrition [34]. These are known facts that factors such as rapid urbanization, sedentary lifestyles, consumption of junk food, and high-energy drinks are concurrently contributing to a surge in rates of overweight and obesity in LMICs, and Nepal is not an exception to it. Our estimates are comparable with previous studies from other South Asian nations, which reported a higher prevalence of overweight and obesity in urban areas than in the rural [21,22,35]. The consequences of obesity, followed by its long-term health conditions such as heart disease, hypertension, stroke, and diabetes, would be detrimental to the fragile public health systems in LMICs [36], including in Nepal [37]. It is estimated that developing countries account for 60% of the burden of chronic diseases globally [12]. Undernourished women are at increased risk of common infectious diseases. Adequate nutrition not only prevents malnutrition but also reduce the risk of chronic diseases [38]. Dealing with both under- and over-nutrition in LMICs requires political commitment, a practical integrated approach, and radical reform in policies and programmes.
Our study findings further corroborated that women in wealthier households and women with primary and secondary education were less likely to be severely thin and more likely to be obese compared to the poorest wealth quintile and among women with no education, respectively. Our finding is comparable with the study reporting a positive association between wealth and obesity and between higher-level education and underweight [28]. Better education can be taken as a proxy indicator of having knowledge of nutritious food, which can eventually lead to an optimal health. However, women in wealthier households can afford to purchase varieties of food and have access to buy widely available sugary and energy-rich commercialized foods resulting in over-nutrition [38]. On the contrary, women in poor socio-economic status have a low opportunity of attaining better education and cannot afford wide-varieties of a nutritious diet and poor access to health services leading to undernutrition. Similarly, currently-working women were less likely to be obese. This evidence is consistent with study findings from Bangladesh that currently-working women had a higher likelihood of being undernourished [39]. Mostly women in Nepal in rural areas work in agriculture and mostly work at home. These women are likely to eat diet lacking nutrition, which makes them at a high risk of being underweight.
Our study included variables of mass media access to women since mass media is a useful and readily available source of information to impart health information on adequate nutrition, and healthy behaviour and lifestyle. Study findings showed that women who listened to the radio and watched television had a lower likelihood of being severely thin and underweight. This finding is in agreement with the study done in Botswana [40], which reported women were less likely to be thin or underweight and had access to mass media. However, the findings concerning access to newspapers were not significant for under- and over-weight. It could be due to the inaccessibility of newspapers which are not available in rural areas, while other media sources such as radio and television are readily available than newsprints in the countryside.
As expected, our study showed that unimproved toilet facility was positively associated with undernutrition. It implies that women without improved toilet facilities were more at risk of being severely thin and underweight. A study from Nigeria involving spatial analysis of malnutrition showed similar results, which indicated that women without access to improved toilet facilities suffer from undernutrition [41]. Unimproved toilet facility and unprotective sources of drinking water, mainly in low-income countries, are the primary causes of infectious diseases which contribute to 7% of the total disease burden [42]. A vicious interaction between malnutrition and infection was reported in a study stating that malnutrition aggravates the pathway of infectious disease, which further conduce malnutrition [43].
The output of nonlinear models showed an increased likelihood of being overweight and obese with a surge in every year of age. On the other hand, a tendency of being underweight was low in younger age-group. Although studies from Ethiopia [44], Pakistan [29] and Bangladesh [22] showed a similar observation, our study purports unbiased estimation showing more likelihood of being overweight and obesity in older women. Younger age-group women reported having low BMI in developing countries than compared to the developed countries. These age groups are involved more in physical activity. As age increases, people tend to have a sedentary lifestyle contributing to an increase in mass body composition in the long run. A study conducted among black and white women reported that BMI increased significantly with the increase in age indicating a linear correlation between body fat percentage [45].