Age patterns in stunting and anaemia in African schoolchildren: a cross-sectional study in Tanzania

Objective: To describe the nutritional status of schoolchildren from a rural area of Tanzania, with a I,articular emphasis on older adolescents to determine the timing of the growth spurt and differences by sex. Design: A cross-sectional survey using a randomly selected sample. Subjects: Six thousand eight hundred and one children aged 7-18 y randomly selected from those enrolled in standards 2-5 in 59 primary schools in Magu District, Tanzania. Results: Overall. 52.5% of children were stunted and 43.0% were underweight, with significantly more buys stunted and underweight than girls. Z-scores of height-for-age for both boys and gills decreased progressively between 5 and 12 y. After 12 y the height-for-age z-scores of girls show a marked upturn, whilst z-scores for boys continue to decrease throughout the school-aged years until 16 y when a slight upturn is observed. Anaemia (Hb < 120 g/L) was present in 62.6% of children. with the prevalence decreasing with age. Anaemia improved throughout the school years for boys, but did nor for girls. Age, sex and hookworm infection a cre significant predictors of anaemia. Conclusion: Stunting and anaemia are exceptionally common conditions in African schoolchildren. The findings highlight important differences between boys and girls, which are suggestive of compensatory growth at 12 y for girls and at 16 y for boys, although it remains unclear whether boys will catch up in height at older ages.