Plasma Retinol Concentrations and Dietary Intakes of Mother-Infant Sets in Singleton versus Twin Pregnancy.

Vitamin A (retinol) is essential for normal fetal development, but the recommendation for maternal dietary intake (Retinol Activity Equivalent, RAE) does not differ for singleton vs. twin pregnancy, despite the limited evaluation of retinol status. Therefore, this study aimed to evaluate plasma retinol concentrations and deficiency status in mother-infant sets from singleton vs. twin pregnancies as well as maternal RAE intake. A total of 21 mother-infant sets were included (14 singleton, 7 twin). The HPLC and LC-MS/HS evaluated the plasma retinol concentration, and data were analyzed using the Mann-Whitney U test. Plasma retinol was significantly lower in twin vs. singleton pregnancies in both maternal (192.2 vs. 312.1 vs. mcg/L, p = 0.002) and umbilical cord (UC) samples (102.5 vs. 154.4 vs. mcg/L, p = 0.002). The prevalence of serum-defined vitamin A deficiency (VAD) <200.6 mcg/L was higher in twins vs. singletons for both maternal (57% vs. 7%, p = 0.031) and UC samples (100% vs. 0%, p < 0.001), despite a similar RAE intake (2178 vs. 1862 mcg/day, p = 0.603). Twin pregnancies demonstrated a higher likelihood of vitamin A deficiency in mothers, with an odds ratio of 17.3 (95% CI: 1.4 to 216.6). This study suggests twin pregnancy may be associated with VAD deficiency. Further research is needed to determine optimal maternal dietary recommendations during twin gestation.

Fenretinide inhibits vitamin A formation from ß-carotene and regulates carotenoid levels in mice.

N-[4-hydroxyphenyl]retinamide, commonly known as fenretinide, a synthetic retinoid with pleiotropic benefits for human health, is currently utilized in clinical trials for cancer, cystic fibrosis, and COVID-19. However, fenretinide reduces plasma vitamin A levels by interacting with retinol-binding protein 4 (RBP4), which often results in reversible night blindness in patients. Cell culture and in vitro studies show that fenretinide binds and inhibits the activity of ß-carotene oxygenase 1 (BCO1), the enzyme responsible for endogenous vitamin A formation. Whether fenretinide inhibits vitamin A synthesis in mammals, however, remains unknown. The goal of this study was to determine if the inhibition of BCO1 by fenretinide affects vitamin A formation in mice fed ß-carotene. Our results show that wild-type mice treated with fenretinide for ten days had a reduction in tissue vitamin A stores accompanied by a two-fold increase in ß-carotene in plasma (P < 0.01) and several tissues. These effects persisted in RBP4-deficient mice and were independent of changes in intestinal ß-carotene absorption, suggesting that fenretinide inhibits vitamin A synthesis in mice. Using Bco1-/- and Bco2-/- mice we also show that fenretinide regulates intestinal carotenoid and vitamin E uptake by activating vitamin A signaling during short-term vitamin A deficiency. This study provides a deeper understanding of the impact of fenretinide on vitamin A, carotenoid, and vitamin E homeostasis, which is crucial for the pharmacological utilization of this retinoid.

Etiology of Anemia in Older Mexican Adults: The Role of Hepcidin, Vitamin A and Vitamin D.

Anemia in older adults is a growing public health issue in Mexico; however, its etiology remains largely unknown. Vitamin A deficiency (VAD) and vitamin D deficiency (VDD) have been implicated in the development of anemia, though by different mechanisms. The aim of this study is to analyze the etiology of anemia and anemia-related factors in older Mexican adults. This is a cross-sectional study of 803 older adults from the southern region of Mexico in 2015. The anemia etiologies analyzed were chronic kidney disease (CKD), nutritional deficiencies (ND), anemia of inflammation (AI), anemia of multiple causes (AMC) and unexplained anemia (UEA). VAD was considered to be s-retinol ≤ 20 µg/dL, and VDD if 25(OH)D < 50 nmol/L. IL-6 and hepcidin were also measured. Multinomial regression models were generated and adjusted for confounders. Anemia was present in 35.7% of OA, independent of sex. UEA, CKD, AI and ND were confirmed in 45%, 29.3%, 14.6% and 7% of older adults with anemia, respectively. Hepcidin and log IL-6 were associated with AI (p < 0.05) and CKD (p < 0.001). VAD was associated with AI (p < 0.001), and VDD with ND and AMC (p < 0.05). Log-IL6 was associated with UEA (p < 0.001). In conclusion, anemia in older adults has an inflammatory component. VAD was associated to AI and VDD with ND and AMC.

Pregnancy and Lactation Alter Vitamin A Metabolism and Kinetics in Rats under Vitamin A-Adequate Dietary Conditions.

BACKGROUND: Vitamin A (VA) plays critical roles in prenatal and postnatal development; however, limited information is available regarding maternal VA metabolism during pregnancy and lactation. OBJECTIVES: We investigated the impact of pregnancy and lactation on VA metabolism and kinetics in rats, hypothesizing that changes in physiological status would naturally perturb whole-body VA kinetics. METHODS: Eight-week old female rats (n = 10) fed an AIN-93G diet received an oral tracer dose of 3H-labeled retinol to initiate the kinetic study. On d 21 after dosing, six female rats were mated. Serial blood samples were collected from each female rat at selected times after dose administration until d 14 of lactation. Model-based compartmental analysis was applied to the plasma tracer data to develop VA kinetic models. RESULTS: Our compartmental model revealed that pregnancy resulted in a gradual increase in hepatic VA mobilization, presumably to support different stages of fetal development. Additionally, the model indicates that during lactation, VA derived from dietary intake was the primary source of VA delivered to the mammary gland for milk VA secretion. CONCLUSION: During pregnancy and lactation in rats with an adequate VA intake and previous VA storage, the internal redistribution of VA and increased uptake from diet supported the maintenance of VA homeostasis.

Vitamin A status, inflammation adjustment, and immunologic response in the context of acute febrile illness: A pilot cohort study among pediatric patients.

BACKGROUND: Vitamin A is necessary for an adequate immune response to infections. Infection also alters vitamin A biomarkers, which interferes with assessment of vitamin A deficiency and thus impairs clinical management. Here we apply multiple strategies to adjust vitamin A biomarkers for inflammation during acute infection and evaluate associations between adjusted vitamin A status and immunologic response markers. METHODS: We measured biomarkers in pediatric patients presenting with acute febrile illness in Guayaquil, Ecuador at paired acute and convalescent visits. Four adjustment strategies were applied to retinol-binding protein (RBP) concentrations: Thurnham correction factor (TCF), BRINDA regression correction (BRC), CRP-only adjustment factor (CRP), and proof-of-concept for a proposed interleukin 6 regression model (IL-6 RM). Adjusted RBP concentrations were compared between visits using the paired Wilcoxon signed-rank test. Multivariate regression analysis was used to assess associations between adjusted vitamin A status and immunologic response markers. RESULTS: A sample of 57 participants completed the acute visit 1, and 18 of these individuals completed the convalescent visit 2. The IL-6 RM was the only strategy resulting in adjusted RBP concentrations that were not significantly different between paired visits (p = 0.20). Following RBP adjustment, 0.0% of participants were classified as vitamin A deficient (RBP ≤ 0.70 µmol/L) and 14.0% were classified as vitamin A insufficient (RBP ≤ 1.05 µmol/L). Adjusted vitamin A insufficiency was associated with an increase in macrophage inflammatory protein 1-alpha (MIP-1α, p = 0.03) and a pro-inflammatory immune response profile (p = 0.03) during the acute visit. CONCLUSIONS: We introduce a strategy for adjusting vitamin A in the context of clinical illness based on IL-6 concentrations that will need to be validated in larger studies. Assessment of vitamin A during infection allows for further understanding of how vitamin A status modulates immunopathology and enables targeted strategies for vitamin A supplementation in the context of infection among children in settings with high burdens of undernutrition and infectious diseases.

Determination of Vitamin A Total Body Stores in Children from Dried Serum Spots: Application in a Low- and Middle-Income Country Community Setting.

BACKGROUND: The retinol isotope dilution (RID) method has been used to evaluate vitamin A (VA) status in healthy adults and children in low- and middle-income countries (LMIC) and to assess the efficacy of various VA interventions. OBJECTIVE: The study was designed to examine whether dried serum spots (DSS) can be applied to RID when conducting VA total body store (TBS) assessments in community settings. METHODS: Four days after an oral dose of 0.4 mg [13C10]retinyl acetate was administered to Filipino children (12-18 mo), a single blood draw was divided to isolate both serum and plasma. Serum (40 µL) was spotted and dried on Whatman 903 cards and shipped at ambient temperature whereas liquid plasma (LP) was frozen at -80°C and shipped on dry ice. The VA tracer to tracee ratio from DSS and LP was quantified by LC-MS/MS. Comparisons between DSS and LP paired samples (n = 72) were made for [13C10]retinol specific activity (SAp) by Pearson's correlation and for VA TBS by Bland-Altman analysis. RESULTS: The sum of 3 coextracted DSS were required to consistently detect [13C10]retinol above the LC-MS/MS limit of quantitation (LOQ). [13C10]retinol SAp from DSS was highly correlated with SAp from LP (r = 0.945; P < 0.01). A comparison of methods for TBS determination using Bland-Altman analysis indicated agreement with an intraindividual difference of 24.7 µmol (4.6%). Mean total liver reserve (TLR) values from DSS and LP were 1.7 µmol/g (± 0.6 SD) and 1.6 µmol/g (± 0.6 SD), respectively. CONCLUSIONS: VA TBS can be determined from DSS thereby reducing the logistics and cost of maintaining a cold chain by shipping samples at ambient temperature and, thus, making the RID technique more feasible in LMIC community settings. This trial was registered at https://clinicaltrials.gov as NCT03030339.

Small-Quantity Lipid-Based Nutrient Supplements Do Not Affect Plasma or Milk Retinol Concentrations Among Malawian Mothers, or Plasma Retinol Concentrations among Young Malawian or Ghanaian Children in Two Randomized Trials.

BACKGROUND: Vitamin A (VA) deficiency is prevalent in preschool-aged children in sub-Saharan Africa. OBJECTIVES: We assessed the effect of small-quantity lipid-based nutrient supplements (SQ-LNS) given to women during pregnancy and lactation and their children from 6 to 18 mo of age on women's plasma and milk retinol concentrations in Malawi, and children's plasma retinol concentration in Malawi and Ghana. METHODS: Pregnant women (≤20 wk of gestation) were randomized to receive daily: 1) iron and folic acid (IFA) during pregnancy only; 2) multiple micronutrients (MMN; 800 µg retinol equivalent (RE)/capsule), or 3) SQ-LNS (800 µg RE/20g) during pregnancy and the first 6 mo postpartum. Children of mothers in the SQ-LNS group received SQ-LNS (400 µg RE/20 g) from 6 to 18 mo of age; children of mothers in the IFA and MMN groups received no supplement. Plasma retinol was measured in mothers at ≤20 and 36 wk of gestation and 6 mo postpartum, and in children at 6 and 18 mo of age. Milk retinol was measured at 6 mo postpartum. VA status indicators were compared by group. RESULTS: Among Malawian mothers, geometric mean (95% CI) plasma retinol concentrations at 36 wk of gestation and 6 mo postpartum were 0.97 µmol/L (0.94, 1.01 µmol/L) and 1.35 µmol/L (1.31, 1.39 µmol/L), respectively; geometric mean (95% CI) milk retinol concentration at 6 mo postpartum was 1.04 µmol/L (0.97, 1.13 µmol/L); results did not differ by intervention group. Geometric mean (95% CI) plasma retinol concentrations for Malawian children at 6 and 18 mo of age were 0.78 µmol/L (0.75, 0.81 µmol/L) and 0.81 µmol/L (0.78, 0.85 µmol/L), respectively, and for Ghanaian children they were 0.85 µmol/L (0.82, 0.88 µmol/L) and 0.88 µmol/L (0.85, 0.91 µmol/L), respectively; results did not differ by intervention group in either setting. CONCLUSIONS: SQ-LNS had no effect on VA status of mothers or children, possibly because of low responsiveness of the VA status indicators.

Relation between Timing of High-Dose Vitamin A Supplementation and Modified-Relative-Dose-Response Values in Children 12-23 Months in Uganda.

BACKGROUND: High-dose vitamin A (VA) supplements (VAS) can temporarily affect VA status. Hence, micronutrient surveys might need to be timed around VAS campaigns to accurately estimate VA deficiency (VAD) prevalence. Little is known about optimal timing of micronutrient surveys when the modified-relative-dose-response (MRDR) is used as a VA indicator. OBJECTIVES: We evaluated the association between days since the end of a VAS campaign and MRDR values in children aged 12-23 mo in Uganda. METHODS: We pooled data from 2 cross-sectional, population-based surveys in eastern Uganda conducted in 2015-2016 (n = 118 children). We estimated the prevalence of VAD (MRDR ≥0.060). Days since the end of a VAS campaign ("days since VAS") was calculated as the interview date minus the end date of the VAS campaign. The MRDR value was assessed using HPLC. We excluded children whose MRDR values were below the limit of detection (<0.007). We used linear regression to evaluate the association between days since VAS and log-transformed MRDR. In adjusted analyses, we controlled for potential confounders. Statistical analyses accounted for the surveys' complex design. RESULTS: The prevalence of VAD was 5.2% (95% CI: 1.1%, 9.3%). Mean days since VAS was 54.1 d (range 39-68 d). Days since VAS was not associated with log-transformed MRDR in unadjusted analyses ($\hat{\beta } = \ $0.0055; 95% CI: -0.009, 0.020; P = 0.45) or adjusted analyses ($\hat{\beta } = $ -0.0073; 95% CI: -0.024, 0.010; P = 0.39). CONCLUSIONS: MRDR measurement through a nutrition survey began as early as 1.3 mo after the end of a VAS campaign in eastern Uganda. Days since the end of a VAS campaign was not associated with MRDR in Ugandan children aged 12-23 mo. Future studies should consider longitudinal designs and evaluate time since VAS and MRDR in children of different ages and in regions with higher VAD prevalence.

Hidden Hunger of Vitamin E among Healthy College Students: A Cross- Sectional Study.

BACKGROUND: College students may have a risk of fat-soluble vitamin deficiencies due to unhealthy dietary habits, especially for vitamin A and E. They are important members of the human antioxidant network; deficiencies of these vitamins may increase the risk of many critical diseases. OBJECTIVE: The current study was undertaken to determine the status of vitamin A and E in college students. METHODS: Healthy college students were recruited, and fasting blood samples of them were collected and used for determining serum levels of retinol and α-tocopherol by the HPLC method. RESULTS: We found that there was no vitamin A deficiency in college students. However, vitamin E deficiency existed in 34.5% of college students, especially in males. All the students had no vitamin E adequacy. In addition, our findings showed that BMI was inversely associated with serum α-- tocopherol, but not serum retinol. CONCLUSION: These results suggest that vitamin E deficiency in college students should be given more attention, and it is necessary to consider using vitamin E supplements.

Vitamin A deficiency increases the risk of gastrointestinal comorbidity and exacerbates core symptoms in children with autism spectrum disorder.

BACKGROUND: Autism spectrum disorder (ASD) is a neurodevelopmental disorder, and many individuals with ASD have gastrointestinal (GI) comorbidities. Vitamin A (VA) is an essential micronutrient that plays an important role in brain development and GI function. METHODS: A total of 323 children with ASD and 180 control children were enrolled in this study. Symptoms of ASD were assessed with the Child Autism Rating Scale (CARS), the Social Responsiveness Scale (SRS), and the Autism Behavior Checklist (ABC). Caregivers of the children completed questionnaires about GI symptoms. Serum retinol levels were detected with high-performance liquid chromatography (HPLC). RESULTS: Children with ASD and with GI comorbidity and constipation had considerably lower serum VA levels than autistic children without these symptoms. VA level was associated with CARS, SRS, and ABC scores, whereas GI symptoms were associated some SRS and ABC scores. The interaction of VAD and GI symptoms appeared to aggravate some of the core symptoms of children with ASD. CONCLUSIONS: VAD exacerbates core symptoms in children with ASD, and ASD children with GI comorbidities also have more serious core symptoms than ASD children without GI comorbidities. VAD comorbid with GI symptoms aggravates autistic children's core symptoms. IMPACT: VAD exacerbates core symptoms in children with ASD. ASD children with GI comorbidities have more serious core symptoms than ASD children without GI comorbidities. VAD comorbid with GI symptoms aggravates autistic children's core symptoms. We speculate that VAD might be related to a subtype of ASD that involves GI comorbidities. We believe that our findings will be of fundamental importance to the scientific community.

Breast Milk-Derived Retinol Is a Potential Surrogate for Serum in the 13C-Retinol Isotope Dilution Test in Zambian Lactating Women with Vitamin A Deficient and Adequate Status.

BACKGROUND: Vitamin A (VA) deficiency (VAD) affects ∼19 million pregnant women worldwide. The extent of VAD in Zambian women of reproductive age is unknown owing to lack of survey inclusion or the use of static serum retinol concentrations, a low-sensitivity biomarker. OBJECTIVES: This cross-sectional study employed isotopic techniques to determine VA status with serum and milk among women aged 18-49 y (n = 197) either lactating with infants aged 0-24 mo or nonlactating with or without infants. METHODS: Assistants were trained and piloted data collection. Demographic data, anthropometry, and relevant histories were obtained including malaria and anemia. For retinol isotope dilution (RID), baseline fasting blood and casual breast milk samples were collected before administration of 2.0 µmol 13C2-retinyl acetate and 24-h dietary recalls. On day 14, blood (n = 144) and milk (n = 66) were collected. Prevalence of total liver VA reserves (TLR) ≤0.10 µmol/g was defined as VAD with comparison to the DRI assumption of 0.07 µmol/g as minimally acceptable for North Americans. RESULTS: When a 20% adjustment for dose lost to milk was made in the RID equation for lactation, mean total body VA stores (TBS) for lactating women were 25% lower than for nonlactating women (P < 0.01), which was not the case without adjustment (P = 0.3). Mean ± SD TLR for all women were 0.15 ± 0.11 µmol/g liver. Using retinol purified from breast milk instead of serum for RID analysis yielded similar TBS and TLR, which were highly correlated between methods (P < 0.0001). Serum retinol ≤0.70 µmol/L had 0% sensitivity using either VAD liver cutoff and milk retinol ≤1.0 µmol/L had 42% sensitivity for VAD at 0.10 µmol/g. CONCLUSIONS: Determining accurate VA status among women of reproductive age, especially lactating women, forms a basis for extrapolation to the general population and informing policy development and program implementation.

Maternal vitamin A deficiency impairs cholinergic and nitrergic neurons, leading to gastrointestinal dysfunction in rat offspring via RARß.

AIMS: Many gastrointestinal (GI) disorders are developmental in origin and are caused by abnormal enteric nervous system (ENS) formation. Maternal vitamin A deficiency (VAD) during pregnancy affects multiple central nervous system developmental processes during embryogenesis and fetal life. Here, we evaluated whether maternal diet-induced VAD during pregnancy alone can cause changes in the ENS that lead to GI dysfunction in rat offspring. MAIN METHODS: Rats were selected to construct animal models of normal VA, VA deficiency and VA supplementation. The fecal water content, total gastrointestinal transmission time and colonic motility were measured to evaluate gastrointestinal function of eight-week-old offspring rats. The expression levels of RARß, SOX10, cholinergic (ChAT) and nitrergic (nNOS) enteric neurons in colon tissues were detected through western blot and immunofluorescence. Primary enteric neurospheres were treated with retinoic acid (RA), infection with Ad-RARß and siRARß adenovirus, respectively. KEY FINDINGS: Our data revealed marked reductions in the mean densities of cholinergic and nitrergic enteric neurons in the colon and GI dysfunction evidenced by mild intestinal flatulence, increased fecal water content, prolonged total GI transit time and reduced colon motility in adult offspring of the VAD group. Interestingly, maternal VA supplementation (VAS) during pregnancy rescued these changes. In addition, in vitro experiments demonstrated that exposure to appropriate doses of RA promoted enteric neurosphere differentiation into cholinergic and nitrergic neurons, possibly by upregulating RARß expression, leading to enhanced SOX10 expression. SIGNIFICANCE: Maternal VAD during pregnancy is an environmental risk factor for GI dysfunction in rat offspring.

Effect of Fat-Soluble Vitamins A, D, E and K on Vitamin Status and Metabolic Profile in Patients with Fat Malabsorption with and without Urolithiasis.

Patients with intestinal fat malabsorption and urolithiasis are particularly at risk of acquiring fat-soluble vitamin deficiencies. The aim of the study was to evaluate the vitamin status and metabolic profile before and after the supplementation of fat-soluble vitamins A, D, E and K (ADEK) in 51 patients with fat malabsorption due to different intestinal diseases both with and without urolithiasis. Anthropometric, clinical, blood and 24-h urinary parameters and dietary intake were assessed at baseline and after ADEK supplementation for two weeks. At baseline, serum aspartate aminotransferase (AST) activity was higher in stone formers (SF; n = 10) than in non-stone formers (NSF; n = 41) but decreased significantly in SF patients after supplementation. Plasma vitamin D and E concentrations increased significantly and to a similar extent in both groups during intervention. While plasma vitamin D concentrations did not differ between the groups, vitamin E concentrations were significantly lower in the SF group than the NSF group before and after ADEK supplementation. Although vitamin D concentration increased significantly in both groups, urinary calcium excretion was not affected by ADEK supplementation. The decline in plasma AST activity in patients with urolithiasis might be attributed to the supplementation of ADEK. Patients with fat malabsorption may benefit from the supplementation of fat-soluble vitamins ADEK.

Vitamin A and iron status of children before and after treatment of uncomplicated severe acute malnutrition.

BACKGROUND & AIMS: Treatment of children with uncomplicated severe acute malnutrition (SAM) is based on ready-to-use therapeutic foods (RUTF) and aims for quick regain of lost body tissues while providing sufficient micronutrients to restore diminished body stores. Little evidence exists on the success of the treatment to establish normal micronutrient status. We aimed to assess the changes in vitamin A and iron status of children treated for SAM with RUTF, and explore the effect of a reduced RUTF dose. METHODS: We collected blood samples from children 6-59 months old with SAM included in a randomised trial at admission to and discharge from treatment and analysed haemoglobin (Hb) and serum concentrations of retinol binding protein (RBP), ferritin (SF), soluble transferrin receptor (sTfR), C-reactive protein (CRP) and α1-acid glycoprotein (AGP). SF, sTfR and RBP were adjusted for inflammation (CRP and AGP) prior to analysis using internal regression coefficients. Vitamin A deficiency (VAD) was defined as RBP < 0.7 µmol/l, anaemia as Hb < 110 g/l, storage iron deficiency (sID) as SF < 12 µg/l, tissue iron deficiency (tID) as sTfR > 8.3 mg/l and iron deficiency anaemia (IDA) as both anaemia and sID. Linear and logistic mixed models were fitted including research team and study site as random effects and adjusting for sex, age and outcome at admission. RESULTS: Children included in the study (n = 801) were on average 13 months of age at admission to treatment and the median treatment duration was 56 days [IQR: 35; 91] in both arms. Vitamin A and iron status markers did not differ between trial arms at admission or at discharge. Only Hb was 1.7 g/l lower (95% CI -0.3, 3.7; p = 0.088) in the reduced dose arm compared to the standard dose, at recovery. Mean concentrations of all biomarkers improved from admission to discharge: Hb increased by 12% or 11.6 g/l (95% CI 10.2, 13.0), RBP increased by 13% or 0.12 µmol/l (95% CI 0.09, 0.15), SF increased by 36% or 4.4 µg/l (95% CI 3.1, 5.7) and sTfR decreased by 16% or 1.5 mg/l (95% CI 1.0, 1.9). However, at discharge, micronutrient deficiencies were still common, as 9% had VAD, 55% had anaemia, 35% had sID, 41% had tID and 21% had IDA. CONCLUSION: Reduced dose of RUTF did not result in poorer vitamin A and iron status of children. Only haemoglobin seemed slightly lower at recovery among children treated with the reduced dose. While improvement was observed, the vitamin A and iron status remained sub-optimal among children treated successfully for SAM with RUTF. There is a need to reconsider RUTF fortification levels or test other potential strategies in order to fully restore the micronutrient status of children treated for SAM.

Modified relative dose response values differ between lactating women in the United States and Indonesia.

IMPACT STATEMENT: Vitamin A (VA) deficiency is a major health issue globally, and lactating women are particularly vulnerable due to increased needs for milk production. Accurate detection of VA deficiency is important; however, most population surveys measure VA status using serum retinol, which is affected by inflammation and lacks sensitivity. The modified relative dose response (MRDR) test qualitatively distinguishes between VA deficiency and sufficiency and could improve population surveys if completed in a randomly selected subsample of individuals in surveys. The original relative dose response test required two blood samples, while MRDR requires only one, a significant improvement in accessibility of the technique by decreasing burden on subjects and investigators. This work demonstrates significant deficiency in Indonesian women compared with US women. In combination with previous research using lactating sows, these human data support milk as a surrogate for blood in the MRDR, which may be less invasive, but requires further validation.

Nutritional status and intestinal parasites among young children from pastoralist communities of the Ethiopian Somali region.

Pastoralist children in the Ethiopian Somali Regional State (ESRS) are at high risk for undernutrition and intestinal parasitic infections (IPIs). We assessed the nutritional status and its association with IPIs in 500 children <5 years of age in a clustered cross-sectional study in Adadle district, ESRS. Stool samples were microscopically examined for IPIs and biomarkers for iron and vitamin A status, anthropometry, and food variety score (FVS) were assessed. Median (interquartile range [IQR]) FVS was 2.0 (2.0, 4.0), and 35% of children were exclusively breastfed up to age 6 months. Prevalence of stunting, wasting, underweight and mid-upper arm circumference (MUAC) <12.5 cm was 30, 34, 40, and 16%, respectively. Median (IQR) haemoglobin, ferritin, and retinol-binding protein concentrations were 9.5 g dL-1 (8.2, 10.9), 6.2 µg L-1 (4.0, 10.2), and 0.8 µmol L-1 (0.67, 0.91), respectively. Prevalence of anaemia, iron, and vitamin A deficiency was 75, 91, and 30%, respectively. IPIs' prevalence was 47%; the most prevalent IPIs were Giardia lamblia (22%) and Ascaris lumbricoides (15%). Giardial infections but not A. lumbricoides increased the risk for MUAC <12.5 cm (adjusted odds ratio [aOR]: 3.50, 95% confidence interval [CI] [2.21, 5.54]). The odds for anaemia were 97% (aOR: 0.03, 95% CI [0.03, 0.07]) and 89% (aOR: 0.11, 95% CI [0.11, 0.23]) less for children with FVS >2 or with exclusive breastfeeding up to 6 months, respectively. Undernutrition and IPIs are alarmingly high in <5 years of age children in ESRS. Giardial infections and low nutritional adequacy of the diet seem to be major contributing factors to the precarious nutritional status and should be addressed by appropriate interventions.

Retinol status and associated factors in mother-newborn pairs.

BACKGROUND: Vitamin A deficiency is still considered to be a nutritional problem during pregnancy, lactation and early childhood. The present study aimed to assess the vitamin A status of women and their newborns in the Brazilian Northeast and to determine the association between retinol in the maternal serum, umbilical cord blood and colostrum. METHODS: Vitamin A status in 65 pairs of women and newborns was assessed from samples of the mother's serum, umbilical cord serum and colostrum using high-performance liquid chromatography. The inadequacy of the vitamin A status of mothers and infants was identified if the retinol values were <0.7 µmol L- 1 in maternal serum or umbilical cord blood or <1.05 µmol L-1 in colostrum. RESULTS: The prevalence of inadequate maternal vitamin A status was 21.5% (95% CI: 11.5%-31.5%) and 13.8% [95% confidence interval (CI) = 5.4%-22.2%] based on maternal serum and colostrum, respectively. Among newborns, 41.5% (95% CI = 29.3%-53.5%) presented a low status of vitamin A based on cord serum. Multiple linear regression analysis identified that maternal serum retinol is a predictor of umbilical cord retinol (P = 0.005). Retinol in maternal serum was lower in mothers who were less educated (P = 0.04) and colostrum retinol was higher in older (P = 0.04) and multiparous (P = 0.002) mothers. CONCLUSIONS: Vitamin A deficiency is a common problem among mothers attended in public hospitals in Northeast Brazil and maternal retinol concentrations are associated with retinol status in newborns. Maternal age, parity and educational level were related to the maternal vitamin A status.

Effect of Vitamin A status during pregnancy on maternal anemia and newborn birth weight: results from a cohort study in the Western Brazilian Amazon.

PURPOSE: Inadequate Vitamin A (VA) status during pregnancy has been associated with maternal anemia and suboptimal newborn birth weight (BW). We assessed the effect of gestational serum retinol and ß-carotene (µmol/L), in different moments during pregnancy, on maternal hemoglobin (Hb, g/L) and anemia (Hb < 110.0 g/L) at delivery, and newborn BW (kg). METHODS: In a prospective cohort study in Cruzeiro do Sul, Western Brazilian Amazon, biomarkers of the VA status were assessed in the second and third trimesters in pregnancy. Serum retinol and ß-carotene were analyzed considering their effects in each and in both assessments (combined VA status), and the difference of serum values between assessments. Multiple linear and Poisson regression models were used with a hierarchical selection of covariates. RESULTS: A total of 488 mother-newborn pairs were surveyed. Combined VA deficiency status increased the risk for maternal anemia (adjusted prevalence ratio: 1.39; 95% CI 1.05-1.84), and was negatively associated with maternal Hb (ß - 3.30 g/L; 95% CI - 6.4, - 0.20) and newborn BW (ß - 0.10 kg; 95% CI - 0.20, - 0.00), adjusted for socioeconomic, environmental, obstetric, and antenatal characteristics, and nutritional indicators. However, the association for newborn BW was no longer significant after further adjustment for plasma ferritin. There were no significant associations between serum ß-carotene and the outcomes studied. CONCLUSION: Poor serum retinol status throughout pregnancy was associated with maternal anemia at delivery in Amazonian women. The current World Health Organization protocols for supplementation during antenatal care should consider VA status for planning recommendations in different scenarios.

Diagnosis of night blindness through standardized interview and electroretinography.

INTRODUCTION: Objective: To compare the diagnosis of NB through the use of the standardized interview of the World Health Organization/Pan American Health Organization (WHO/PAHO) with electroretinography, and also to evaluate the association of these diagnoses with serum concentrations of retinol in class III obesity individuals. Methods: Adult patients of both genders, in the 20-60 age group, with BMI ≥ 40 kg/m² were studied. NB was diagnosed through electroretinography and the standardized interview validated by the WHO/PAHO. Serum level of retinol was quantified by the HPLC-UV method, and VAD was diagnosed when levels were <1.05 µmol /L, and severity was also evaluated. Statistical analysis was carried out through the Statistical Package for the Social Sciences, version 21.0 (p < 0.05). Results: Mean BMI was 44.9  11.8 kg/m², and a negative correlation was found in serum levels of retinol (p= 0.01). The prevalence of VAD, according to the serum concentrations of retinol, was 14%, and of this percentage 23.3% had NB according to the standardized interview, and 22.0% according to electroretinography. NB diagnosed by both methods showed an association with VAD according to the serum concentrations of retinol. Of these individuals with NB, according to the standardized interview, 6.9% showed severe VAD, 10.3% moderate VAD and 82.8% marginal VAD. Conclusion: The standardized interview for the diagnosis of NB can be a good strategy to evaluate the nutritional status of vitamin A, and it is a simple, non-invasive and low-cost method.

INTRODUCCIÓN: Objetivo: Comparar el diagnóstico de NB mediante el uso de la entrevista estandarizada de la Organización Mundial de la Salud/Organización Panamericana de la Salud (OMS/OPS) con electrorretinografía, y también evaluar la asociación de estos diagnósticos con las concentraciones séricas de retinol en la clase III personas obesas. Métodos: se estudiaron pacientes adultos de ambos sexos, en el grupo de 20 a 60 años de edad, con un IMC ≥ 40 kg/m². La NB se diagnosticó mediante electrorretinografía y la entrevista estandarizada validada por la OMS/OPS. El nivel sérico de retinol se cuantificó mediante el método HPLC-UV, y el DVA se diagnosticó cuando los niveles eran <1.05 µmol / L, y también se evaluó la gravedad. El análisis estadístico se realizó a través del Paquete Estadístico para las Ciencias Sociales, versión 21.0 (p <0.05). Resultados: IMC promedio fue de 44.9 ± 11.8 kg / m², y se encontró una correlación negativa en los niveles séricos de retinol (p = 0.01). La prevalencia de DVA, según las concentraciones séricas de retinol, fue del 14%, y de este porcentaje, el 23,3% tenía NB de acuerdo con la entrevista estandarizada y el 22,0% según la electrorretinografía. La NB diagnosticada por ambos métodos mostró una asociación con VAD según las concentraciones séricas de retinol. De estos individuos con NB, según la entrevista estandarizada, el 6,9% mostró VAD grave, el 10,3% de VAD moderado y el 82,8% de VAD marginal. Conclusión: la entrevista estandarizada para el diagnóstico de NB puede ser una buena estrategia para evaluar el estado nutricional de la vitamina A, y es un método simple, no invasivo y de bajo costo.

Association of vitamin D, retinol and zinc deficiencies with stunting in toddlers: findings from a national study in Iran.

OBJECTIVE: The objective of this study was to investigate the association of serum levels of 25(OH)D3 (vitamin D), retinol (vitamin A) and zinc with stunting in a large sample of Iranian toddlers. STUDY DESIGN: This was a cross-sectional study. METHODS: A total of 4261 children, aged 10-36 months, who had Iranian birth certificates were included in the present study. Weight and height were measured by experienced professionals in accordance with standard protocols. Stunting was defined as a height-for-age z-score of <-1 standard deviation (SD) based on the World Health Organization (WHO) criteria (the WHO Child Growth Standards median). Serum levels of 25(OH)D3, retinol and zinc were examined based on standard methods. RESULTS: The mean age of the study participants was 19.2 ± 8.4 months. A significant inverse association was found between serum retinol concentrations and the odds of stunting such that after controlling for potential confounders, toddlers in the highest quartile of serum retinol levels had 29% lower odds of stunting than those in the lowest quartile (odds ratio [OR]: 0.71, 95% confidence interval [CI]: 0.53-0.97). Furthermore, a significant inverse association was found between serum levels of retinol and stunting in girls (OR: 0.57, 95% CI: 0.34-0.94), urban toddlers (OR: 0.66, 95% CI: 0.44-0.99) and those who did not use nutritional supplements (OR: 0.70, 95% CI: 0.52-0.95). Although serum 25(OH)D3 levels were not significantly associated with stunting in the overall study population, we found a positive association among toddlers who used nutritional supplements. No significant association was found between serum levels of zinc and stunting. CONCLUSION: We found a significant inverse association between serum levels of retinol and stunting in toddlers aged 10-36 months.