The impact of season and climate on growth during early childhood in different socio-economic groups in Lahore, Pakistan

Aim. The aim of this study was to analyse the impact of season and climate on early child growth in four socio-economically different groups living in Lahore, Pakistan. Methods. A prospective cohort study was conducted among children living in a village, periurban slum area, urban slum area and a group of children from the upper middle class. Monthly observations were made on 1476 infants from birth to 24 months. Growth in terms of length and weight were analysed in relation to age, socioeconomical group, and season of the year and different climate variables such as rain, day temperature and humidity. The longitudinal data was analysed by the derived variable method and regression models. Results. Season of birth did not have any important impact on the birth weight or length. There were differences in weight gain during the first six months as well as between 6-12 months, depending on which time of the year the child was born. This seasonal differences was most prominent in the poorer groups. The climate variable mean day temperature was negatively correlated to weight gain with a p-value