Methods for assessing seasonal and annual trends in wasting in Indian surveys (NFHS-3, 4, RSOC & CNNS)

Abstract

Wasting in children under-five is a form of acute malnutrition, a predictor of under-five child mortality and of increased risk of future episodes of stunting and/or wasting. In India, national estimates of wasting are high compared to international standards with one in five children found to be wasted. National surveys are complex logistical operations and most often not planned or implemented in a manner to control for seasonality. Collection of survey data across differing months across states introduces seasonal bias. Cross-sectional surveys are not designed to collect data on seasonality, thus special methods are needed to analyse the effect of data collection by month. We developed regression models to estimate the mean weight for height (WHZ), prevalence of wasting for every month of the year for an average year and an overall weighted survey estimates controlling for the socio-demographic variation of data collection across states and populations over time. National level analyses show the mean WHZ starts at its highest in January, falls to the lowest in June/August and returns towards peak at year end. The prevalence of wasting is lowest in January and doubles by June/August. After accounting for seasonal patterns in data collection across surveys, the trends are significantly different and indicate a stagnant period followed by a decline in wasting. To avoid biased estimates, direct comparisons of acute malnutrition across surveys should not be made unless seasonality bias is appropriately addressed in planning, implementation or analysis. Eliminating the seasonal variation in wasting would reduce the prevalence by half and provide guidance towards further reduction in acute malnutrition.

WITHDRAWN: Estimates of Undernutrition among migrant/refugee children in lower-middle-income countries: A meta-analysis of published evidence from 2010-2022

“…53 Wasting has been reported to be more prevalent during the monsoon season because of an increased incidence of infectious diseases including diarrheal outbreaks and the lack of availability of previously harvested food. 41,[54][55][56] The availability of sanitation and hygiene practices of the migrants also contributed to the development of different vector borne diseases occurring during the summer and monsoon months. Roshania et al 36 in her study reported reduced age-related intake of food during the summer months owing to the reduced availability and increased food prices during these months thereby increasing the incidences of stunting and wasting.…”

Forecasting Seasonal Acute Malnutrition: Setting the Framework

“…Structural missingness may occur for various reasons. 35,36 It is likely that worsening in these principal properties appears not at random, with the more vulnerable and food insecure areas particularly suffering from lack of data. It means that the forecast obtained from only available data, when more food insecure areas reporting less accurate information, is at risk of underestimating the forecasted seasonal malnutrition.…”

Daytime Heat Wave Seasonal Variability over India

“…The implications are substantial, particularly given that extreme events such as heat waves pose considerable challenges to societies and are integral to the complexities of climate change (Zhao et al, 2023). However, it is known that India experiences significant variations in agro-climatic conditions throughout the year, and seasonality has a strong effect on temperature, diets, food availability, vitamin deficiency, disease, labor conditions/incomes, water availability and sanitation, caring practices, infant and young child feeding, and even health-seeking behaviors (Johnston et al, 2021;WHO, 2023). This is why the seasonality analysis of HW is a need of society, which will help in adaptation and mitigation strategies and policies to cope with climate change.…”