To examine the relationship between serum retinol and biochemical indices of iron nutritional status amongst adolescent girls in urban Bangladesh.
A cross-sectional study.
Girls' high schools in Dhaka City, Bangladesh.
Adolescent girls, n = 225, aged between 12 and 15 years, from four urban schools participated in the study. Information on socio-economic conditions were obtained using a questionnaire. The height and weight of each girl were measured and a sample of blood was taken for biochemical analyses.
Twenty-two per cent of the participants were found to be anaemic (Hb < 120 g/l), 15% had subnormal serum iron (< 7.16 mumol/l) and about 25% were iron deficient judged by serum transferrin saturation (TS < 15%). Eleven per cent of the participants had low levels of serum retinol (< 1.05 mumol/l). Anaemic girls (n = 51) were found to have significantly lower serum retinol as well as lower packed cell volume (PCV), mean corpuscular haemoglobin concentration (MCHC), serum iron, TS, and higher serum total iron binding capacity (TIBC) compared with those with normal haemoglobin levels. When the girls were classified by serum retinol, the third with the highest serum retinol had significantly higher levels of haemoglobin, PCV, MCHC and serum iron levels. When age, family size, family income, expenditure on food, education of the parents, supplementation with vitamin A or iron and menstruation at the time of study were accounted for by multiple regression analysis, a strong relationship was found for serum retinol concentration with PCV, MCHC, haemoglobin, serum iron and TS. For 1 mumol/l change in serum retinol concentration there was a 10.1 g/l change in haemoglobin whilst taking other factors into account.
The data indicate that there is an interaction between serum retinol and biochemical indices of iron nutriture in adolescent girls who do not display any clinical signs of overt deficiency.