Estado nutricional bioquímico de vitamina A de parturientes atendidas na cidade de Natal-RN

Abstract

This study aimed to evaluate the vitamin A status of women who delivered in Natal/RN. A total of 795 women were enrolled in the study. Serum (n=619) and colostrum (n=656) samples were collected in the hospital after an overnight fast. Mature milk samples (n=15) were collected at the women’s house thirty days after delivery. Biochemical indicators were evaluated according to home location (capital city vs. country towns) and type of health care system (public vs. private). Vitamin A intake was assessed using a food-frequency questionnaire (FFQ) corresponding to the last trimester of pregnancy. In order to evaluate the different forms of maternal supplementation with vitamin A and their associations with biochemical markers (maternal serum and breast milk), subgroups were formed based on the type of supplementation that occurred during pregnancy: GC, F1, F2, F3 and postpartum: GM. Retinol concentrations in the biological samples were quantified by high performance liquid chromatography (HPLC). For the total sample, the mean serum retinol concentration was 41.8 ±12.9μg/dL and the prevalence of VAD was 5.3% (n=33) of women presenting retinol concentrations (<20 μg/dL), evidencing a significant difference in serum retinol concentrations between women from the capital city and from the countryside (p <0.01). In Natal, the prevalence of disability found in the north, south, east and west were, respectively, 4.3% (n= 6), 5.6% (n= 7), 2.9% (n= 3) and 11.9% (n= 8). The overall mean retinol concentration in colostrum was 95.3 ± 53.7μg/dL; however, 27.3% (n=179) of women presented inadequate values (<60 μg/dL). The average estimated amounts of retinol provided to newborns through colostrum did not meet the minimum recommendation of 400 μg/RAE/day of AI (Adequate Intake) for newborns in both groups, considering the intake of 396mL/day. It was found a significant difference in colostrum retinol concentrations between women from the capital city and from the countryside (p<0.01). In Natal, colostrum milk of women from the northern and western regions did not meet the AI. For mature milk, none of the groups from the different regions met the recommendation, considering the intake of 780mL/day. Evaluating the sample separately by childbirth care system (public vs. private), it was found a significant difference in serum and colostrum retinol concentrations between the groups (p <0.0001); there was no difference for the mature milk (p>0.05). Estimating the retinol supply through colostrum and mature milk, women attending the public health system did not provide the minimum vitamin A amount recommended for newborns (AI= 400μg/RAE/day), unlike women's private network, which provided. The average total dietary vitamin A intake of pregnant women was 987.1 ± 674.4 μgRAE/day, was 872.2 + 639.2 μgRAE/day for women attending the public health system and 1169.2 + 695.2 μgRAE/day for those attending the private system, evidencing a highly significant difference (p<0.001). Individually assessing the participants, 38.4% (n=100) e 17.3% (n=28) of women in the public and private systems had vitamin A intakes below the ideal. There was no difference in serum retinol concentrations between the CG, F1, F2, F3 and MG groups (p<0.05), although only the supplemented groups F1, F2 and F3 had no cases of VAD. Regarding colostrum retinol levels, the F2 group (beta-carotene) presented the highest number of inadequate cases (40%). The F2 and MG groups did not provide the minimum amount of retinol recommended by AI for newborns. Regarding retinol concentrations in mature milk, there was no difference between the CG, F1, F2, F3 and MG groups, and the MG group presented the lowest percentage of inadequacy (14.3%), while the CG and F2 groups did not provide the minimum amount of retinol recommended by the AI for infants. It was concluded that the prevalence of VAD among mothers who delivered in Natal was considered a “mild” public health problem in the overall population. High-risk groups in this study lived in towns, were attended in the public health system and did not take vitamin A as regular supplement during pregnancy.