Effects of maternal vitamin A status on kidney development: a pilot study
- 200 Downloads
Nephron endowment ranges widely in normal human populations. Recent autopsy studies have drawn attention to the possibility that subtle congenital nephron deficits may be associated with increased risk of developing hypertension later in life. Since modest maternal vitamin A deficiency reduces nephron number in rats, we designed a pilot study to determine the prevalence of maternal vitamin A deficiency in Montreal (Canada) and Bangalore (India) and the usefulness of newborn renal volume as a surrogate for nephron endowment. Among 48 pregnant Montreal women, two (4%) had one isolated mid-gestation retinol level slightly below the accepted limit of normal (0.9 μmol/L), whereas 25 (55%) of 46 pregnant women in Bangalore had at least one sample below this limit. Average estimated retinoid intake was correlated with mean serum retinol in pregnant women from Bangalore. In Montreal where maternal vitamin A deficiency was negligible, we found that newborn renal volume (estimated by renal ultrasonography at 2–6 weeks of age) was correlated with surface area at birth and was inversely correlated with serum creatinine at 1 month. Interestingly, renal volume adjusted for body surface area in Montreal (184±44 ml/m2) was significantly greater than in Bangalore (114±33 ml/m2) (p<0.01). Definitive studies are needed to establish whether maternal vitamin A deficiency accounts for subtle renal hypoplasia in Indian newborns. If so, there may be important public health implications for regions of the world where maternal vitamin A deficiency is prevalent.
KeywordsRenal hypoplasia Vitamin A Nephron endowment Retinol Pregnancy Newborn kidney
This study was supported by a grant from the McGill University Health Centre Research Institute. Paul Goodyer is the recipient of a Canadian Institutes of Health Research (James McGill) Chair.
- 11.Vaz MBA MS, Navada S, Anamika AM, Smitha JT, Kurpad A (2006) The repeatability and relative validity of an interviewer based food frequency questionnaire designed for use in a middle class cosmopolitan south Indian city. J Assoc Physicians India (in press)Google Scholar
- 12.Buzzard M (1998) Nutritional epidemiology. Oxford University Press, LondonGoogle Scholar
- 16.Congdon NG, Dreyfuss ML, Christian P, Navitsky RC, Sanchez AM, Wu LS, Khatry SK, Thapa MD, Humphrey J, Hazelwood D, West KP Jr (2000) Responsiveness of dark-adaptation threshold to vitamin A and beta-carotene supplementation in pregnant and lactating women in Nepal. Am J Clin Nutr 72:1004–1009PubMedGoogle Scholar
- 19.Porteous S, Torban E, Cho NP, Cunliffe H, Chua L, McNoe L, Ward T, Souza C, Gus P, Giugliani R, Sato T, Yun K, Favor J, Sicotte M, Goodyer P, Eccles M (2000) Primary renal hypoplasia in humans and mice with PAX2 mutations: evidence of increased apoptosis in fetal kidneys of Pax2(1Neu)±mutant mice. Hum Mol Genet 9:1–11PubMedCrossRefGoogle Scholar
- 22.Muthayya S, Kurpad AV, Duggan CP, Bosch RJ, Dwarkanath P, Mhaskar A, Mhaskar R, Thomas A, Vaz M, Bhat S, Fawzi WW (2006) Low maternal vitamin B(12) status is associated with intrauterine growth retardation in urban South Indians. Eur J Clin Nutr 60:791–801Google Scholar