Malnutrition as a cause of mental retardation: A population-based study from Sub-Himalayan India

BACKGROUND: Mental retardation is one of the most common disabilities of childhood. The research on childhood malnutrition and its relationship with cognitive functioning suggests that malnutrition alone does not cause mental retardation. OBJECTIVE: To identify the relation between malnutrition and cognition among children from a Sub-Himalayan state in North India. MATERIALS AND METHODS: A two-phase cross-sectional study was conducted in the rural, urban, and slum area of district Kangra. A 30-cluster sampling technique was used to screen a population of children 1–10 years of age from five randomly selected panchayats (village government units) of district Kangra. The screening was based on a modified version of the ten questions screen, adapted to the local population. In the first phase, a door-to-door survey was done to identify suspects of mental retardation. In the second phase, the children found positive in the first phase were called for clinical examination to confirm mental retardation. Anthropometric assessment of all study children was done by measuring weight and height. The nutritional assessment was done by categorizing them according to Waterlow classification for malnutrition. RESULTS: Out of the total 5300 children, 1.7% were diagnosed as mentally retarded. No positive association was reported with different types of malnutrition and mental retardation. A weakly positive association existed between nutritional status and mental retardation (correlation coefficient-0.04). Children who were both wasted and stunted had the highest risk (odds ratio, 95% confidence interval – 5.57, 2.29–10.36) of mental retardation as compared to normal. CONCLUSION: Malnutrition may be one of the causes but certainly not the only cause of mental retardation. Other causes may be contributing more significantly toward it.