Thiamin and riboflavin status with related enzyme activities in pulmonary tuberculosis with diabetes mellitus in Shandong province of China

BACKGROUND AND OBJECTIVES

Poor nutritional status is a common finding in pulmonary tuberculosis (TB) patients with and without type 2 diabetes mellitus (T2DM), thiamin (VB-1) and riboflavin (VB-2) are coenzymes important for the activation of many enzymes involved in improving nutritional status. We aimed to investigate enzymatic activities and the associations between VB-1 and VB-2, and their relations to nutritional status in TB and TB+T2DM patients.

METHODS AND STUDY DESIGN

This was a cross-sectional study that prospectively enrolled TB 40 patients with or without T2DM respectively from the Chest Hospital of Qingdao and 76 healthy controls with similar age and gender distributions were recruited from the medical center of the affiliated hospital of Qingdao Medical College. The erythrocyte transketolase activation coefficient (ETKac, for VB-1 deficiency), the glutathione reductase activation coefficient (EGRac, for VB-2 deficiency), and metabolic enzyme activities were analyzed.

RESULTS

VB-1 and VB-2 deficiency rates were higher, and enzyme activities were lower in TB and TB+T2DM relative to control group. ETKac and EGRac were negatively correlated with enzyme activities, either with body mass index (BMI), while enzyme activities were positively associated with BMI.

CONCLUSIONS

VB-1 and VB-2 concentrations were lower in TB patients with or without T2DM relative to controls, with concomitant reductions in the activity levels of key metabolic enzymes. Significant correlations were observed between VB-1 and VB-2 concentrations and the activity of these metabolic enzymes, they all correlated with nutrition status. VB-1 and VB-2 concentrations may thus impact metabolic enzyme activity and thereby influence nutritional status.

The Homozygous Hemoglobin EE Variant Is Associated with Poorer Riboflavin Status in Cambodian Women of Reproductive Age

BACKGROUND

Riboflavin is required for erythropoiesis, which is increased in people with hemoglobinopathies due to increased hemolysis and erythrocyte turnover. Dietary intake and status of riboflavin is poor in Cambodia, where hemoglobinopathies are common.

OBJECTIVE

We assessed the association between genetic hemoglobin disorders and riboflavin status in women of reproductive age in Cambodia.

METHODS

Venous blood samples from 515 Cambodian women of reproductive age, 18-45 y, were analyzed for biomarker status of riboflavin [erythrocyte glutathione reductase activation coefficient (EGRac)], genetic hemoglobin (Hb) disorders, and hematological indices. Linear regression analysis was used to estimate the association between EGRac with Hb, ferritin, and Hb genotypes. EGRac was log transformed in the analyses, and the regression coefficients represent the geometric mean differences.

RESULTS

Genetic Hb disorders were present in 57% of the population, with the homozygous hemoglobin E variant (Hb EE) occurring in ∼10% of women (n = 53). Deficient (EGRac ≥1.40) or marginal riboflavin status (EGRac ≥1.30 and <1.40) was observed in 92% (n = 475) of women. The variant Hb EE genotype was associated with 18% (95% CI: 9%, 28%) higher geometric mean EGRac values than the normal Hb AA genotype (P < 0.001).

CONCLUSIONS

Although riboflavin biomarker deficiency or marginal status is widely prevalent in Cambodian women, lower riboflavin status was observed more frequently in women with the Hb EE genotype than in women with normal Hb AA. The relation between genetic Hb disorders and riboflavin warrants further investigation. This trial was registered at clinicaltrials.gov as NCT01593423 and NCT02481375.

Micronutrient-Fortified Milk and Academic Performance among Chinese Middle School Students: A Cluster-Randomized Controlled Trial

Many children suffer from nutritional deficiencies that may negatively affect their academic performance. This cluster-randomized controlled trial aimed to test the effects of micronutrient-fortified milk in Chinese students. Participants received either micronutrient-fortified (n = 177) or unfortified (n = 183) milk for six months. Academic performance, motivation, and learning strategies were estimated by end-of-term tests and the Motivated Strategies for Learning Questionnaire. Blood samples were analyzed for micronutrients. In total, 296 students (82.2%) completed this study. Compared with the control group, students in the intervention group reported higher scores in several academic subjects (p < 0.05), including languages, mathematics, ethics, and physical performance at the end of follow-up. Students in the intervention group showed greater self-efficacy and use of cognitive strategies in learning, and reported less test anxiety (p < 0.001). Moreover, vitamin B₂ deficiency (odds ratio (OR) = 0.18, 95% confidence interval (CI): 0.11~0.30) and iron deficiency (OR = 0.34, 95% CI: 0.14~0.81) were less likely in the students of the intervention group, whereas vitamin D, vitamin B₁₂, and selenium deficiencies were not significantly different. “Cognitive strategy” had a partial mediating effect on the test scores of English (95% CI: 1.26~3.79) and Chinese (95% CI: 0.53~2.21). Our findings suggest that micronutrient-fortified milk may improve students’ academic performance, motivation, and learning strategies.

Relationships among Production Systems, Preschool Nutritional Status, and Pesticide-Related Toxicity in Seven Ecuadorian Communities: A Multi-Case Study Approach

Background

Among small Andean potato farmers, greater pesticide use and better linkage to markets are promoted as ways to improve farm outputs and incomes. The health of household members is assumed to improve with higher incomes, although evidence to support such an assumption remains scarce.

Objective

Using a multidisciplinary approach, we sought to characterize agricultural systems producing potatoes and to assess relationships between these characteristics and farm household health indicators.

Methods

We included seven communities linked to a regional agricultural potato production platform (socio-organizational “space” for potato commercialization) in Chimborazo, Ecuador. The unit of analysis was the community, each of which was classified according to its level of intensity of potato production as more intensive, intermediate, or less intensive. Data on crop management, household food intake, child anthropometry, and impacts of pesticide use on adult health were collected by survey.

Results

The net income from potato production was similar in communities with more intensive and intermediate production systems and lower in those with less intensive systems. However, deficits in protein intake were more common among children in communities with more intensive systems (63%) than among those in communities with intermediate (53%) and less intensive (37%) systems. Deficits in thiamin and riboflavin intake were more prevalent in communities with more and less intensive systems than in those with intermediate systems. In contrast, the prevalence of moderate chronic malnutrition, as measured by height-for-age, was greater among children in communities with less intensive systems (27%) than among those in communities with intermediate (5%) and more intensive (7%) systems. Across all intensities, frequent use of highly hazardous pesticides was associated with adverse health effects.

Conclusions

Agricultural development programs need to work more cross-sectorally to realize the potential health benefits associated with intensification of production.

Suspected outbreak of riboflavin deficiency among populations reliant on food assistance: a case study of drought-stricken Karamoja, Uganda, 2009-2010

BACKGROUND

In 2009, a humanitarian response was launched to address a food security and livelihoods crisis in Karamoja, Uganda. During a polio immunization campaign in mid-August 2009, health workers in Nakapiripit District reported a concern about an increase in mouth sores, or angular stomatitis (AS) and gum ulcerations, among children in one village, and an investigation was launched.

OBJECTIVE

This article describes the investigation, lessons learned, and provides guidance for monitoring micronutrient deficiencies among populations receiving food assistance.

DESIGN

An investigation into a suspected outbreak of riboflavin (vitamin B2) deficiency was initiated, including a rapid assessment, mass screening, a convenience sample collection of blood specimens (n = 58 symptomatic cases and n = 18 asymptomatic individuals), and analysis of the general food ration (70% ration).

RESULTS

Findings showed signs of AS in only 399 (0.2%) of 179,172 screened individuals, including adults and children. Biochemical analysis confirmed riboflavin deficiency in 84.5% of specimens from symptomatic individuals and 94.4% of specimens from asymptomatic individuals. Ration distribution data showed that 55% of distributions provided less than half the riboflavin RDA.

CONCLUSION

Evidence was insufficient to confirm an actual outbreak of riboflavin deficiency, though the present investigation adds further documentation that micronutrient deficiencies continue to persist among populations in emergency settings. This article describes challenges, lessons learned, and guidance for monitoring micronutrient deficiencies among food assistance recipients, including: ongoing nutrition monitoring and surveillance; training and sensitization about micronutrient deficiencies, sensitization of the population about locally-available food, and identifying ways to improve micronutrient interventions.

Supplementation with iron and riboflavin enhances dark adaptation response to vitamin A-fortified rice in iron-deficient, pregnant, nightblind Nepali women

BACKGROUND

Nightblindness affects 16-52% of pregnant women in areas of Nepal and in some cases persists after vitamin A treatment. Iron and riboflavin affect vitamin A utilization and photoreceptor function, respectively, and pilot data in the study population showed a high prevalence of iron and riboflavin deficiencies.

OBJECTIVE

The objective was to assess the effect of supplemental iron and riboflavin on pupillary threshold (PT) and plasma retinol in nightblind, pregnant Nepali women given vitamin A-fortified rice.

DESIGN

Nightblind pregnant women were randomly assigned to receive, 6 d/wk under supervision for 6 wk, a vitamin A-fortified rice curry dish providing 850 microg retinal activity equivalents/d with either a 30-mg Fe and 6-mg riboflavin (FeR + VA) capsule or a placebo control (VA only) capsule. Hemoglobin, erythrocyte riboflavin, and plasma ferritin and retinol were measured before and after the intervention. Dark adaptation was assessed by PT score.

RESULTS

Women who were iron deficient at baseline (n=38) had significantly greater improvement in PT score with iron and riboflavin supplementation than without (P=0.05). Iron and riboflavin supplements significantly reduced the prevalences of riboflavin deficiency (from 60% to 6%; P<0.0001), iron deficiency anemia (from 35% to 15%; P<0.007), and abnormal PT (from 87% to 30%; P<0.05) from baseline. Mean increases in erythrocyte riboflavin (P<0.0001) and plasma ferritin (P=0.01) were greater in the FeR + VA group than in the VA only group.

CONCLUSIONS

Iron deficiency may limit the efficacy of vitamin A to normalize dark adaptation in pregnant Nepali women. Further studies are needed to assess the effect of simultaneous delivery of iron and vitamin A for the treatment of nightblindness.

Mild riboflavin deficiency is highly prevalent in school-age children but does not increase risk for anaemia in Côte d'Ivoire

There are few data on the prevalence of riboflavin deficiency in sub-Saharan Africa, and it remains unclear whether riboflavin status influences the risk for anaemia. The aims of this study were to: (1) measure the prevalence of riboflavin deficiency in children in south-central Côte d'Ivoire; (2) estimate the riboflavin content of the local diet; and (3) determine if riboflavin deficiency predicts anaemia and/or iron deficiency. In 5- to 15-year-old children (n281), height, weight, haemoglobin (Hb), whole blood zinc protoporphyrin (ZPP), erythrocyte glutathione reductase activity coefficient (EGRAC), serum retinol, C-reactive protein (CRP) and prevalence ofPlasmodiumspp. (asymptomatic malaria) andSchistosoma haematobium(bilharziosis) infections were measured. Three-day weighed food records were kept in twenty-four households. Prevalence of anaemia in the sample was 52 %; 59 % were iron-deficient based on an elevated ZPP concentration, and 36 % suffered from iron deficiency anaemia.Plasmodiumparasitaemia was found in 49 % of the children. Nineteen percent of the children were infected withS. haematobium. Median riboflavin intake in 5- to 15-year-old children from the food records was 0·42 mg/d, ~47 % of the estimated average requirement for this age group. Prevalence of riboflavin deficiency was 65 %, as defined by an EGRAC value >1·2. Age, elevated CRP and iron deficiency were significant predictors of Hb. Riboflavin-deficient children free of malaria were more likely to be iron deficient (odds ratio; 3·07; 95 % CI 1·12, 8·41). In conclusion, nearly two-thirds of school-age children in south-central Côte d'Ivoire are mildly riboflavin deficient. Riboflavin deficiency did not predict Hb and/or anaemia, but did predict iron deficiency among children free of malaria.

The coexistence of other micronutrient deficiencies in anaemic adolescent schoolgirls in rural Bangladesh

OBJECTIVE

To investigate the prevalence of selected micronutrient deficiencies amongst anaemic adolescent schoolgirls in rural Bangladesh and to examine their relationship with haemoglobin (Hb) levels.

DESIGN

A cross-sectional study.

SETTING

Girls' high schools in rural areas of Dhaka District in Bangladesh.

SUBJECTS AND METHODS

Three hundred and ten anaemic adolescent girls aged 14-18 years from eight schools participated in the study. Information on personal characteristics and food habits were collected by interview. Parents were asked about their socio-economic conditions. Anthropometric data and blood samples were collected following the interview.

RESULTS

Twenty-eight per cent of the girls had depleted iron stores (serum ferritin <12.0 microg/l), 25% had folic acid deficiency (red blood cell folic acid <317 nmol/l), 89% had vitamin B(2) (erythrocyte glutathione reductase activity coefficient > or =1.4) and 7% had vitamin B(12) deficiencies (serum vitamin B(12) <150 pmol/l). Although the prevalence of vitamins A and C deficiency was very low, a significant proportion had low vitamin A (serum retinol between 0.70 and <1.05 micromol/l) and vitamin C status (plasma ascorbic acid between 11.4-23.0 micromol/l). Frequency of consumption of meat, serum ferritin and vitamin B(2) status were found to be strongly related to Hb by multiple regression analysis. For 1 microg/l change in serum ferritin, there was a 0.13 g/l change in Hb when adjusted for other factors.

CONCLUSIONS

There is coexistence of micronutrient deficiencies among anaemic adolescent girls in rural Bangladesh, although they do not suffer from energy deficiency. Of all micronutrients, only iron and vitamin B(2) concentrations were found to be related to the Hb concentration.

Riboflavin status in acute ischaemic stroke

BACKGROUND

There is experimental evidence that riboflavin (vitamin B2) supplementation reduces oxidative damage and cerebral oedema following acute stroke.

OBJECTIVE

To measure riboflavin levels in acute stroke before and after supplementation with this vitamin.

DESIGN

Ninety-six acute ischaemic stroke patients had their riboflavin status measured at baseline and then randomly assigned to receive 5 mg of oral riboflavin and other B-group vitamins within 12 h of the stroke onset and then daily or no B-vitamins for 14 days. Non-fasting venous blood was obtained at baseline, days 7 and 14 post-randomization for measurement of riboflavin status using erythrocyte glutathione reductase activity coefficient (EGRAC). EGRAC is a measure of riboflavin tissue saturation. This assay has the advantage of being extremely stable and sensitive. EGRAC values are inversely proportional to riboflavin status, so that values greater than 1.3 indicate biochemical deficiency.

RESULTS

Fifty-one per cent of patients studied were riboflavin deficient at baseline. Fourteen days of riboflavin supplementation significantly improved the measure of B2 status compared with the control group. Seven out of 37 patients in the supplement group (19%) were riboflavin deficient compared with 22 out of 39 patients (56%) in the control group at the end of the treatment period (P=0.035 for the differences in cumulative changes between groups over 2 weeks).

CONCLUSIONS

A high proportion of acute stroke patients were biochemically deficient of riboflavin immediately post-infarct. Supplementation with 5 mg of riboflavin for 2 weeks significantly improved riboflavin status; however, the clinical significance of these findings is not yet known.

Thiamin and riboflavin status of Taiwanese elementary schoolchildren

In The Nutrition and Health Survey of Taiwan Elementary School Children (NAHSIT Children 2001~2002), erythrocyte activity coefficients of transketolase (ETKAC) and glutathione reductase (EGRAC) were chosen as indices for assessing the functional status of thiamin and riboflavin nutriture. Mean values of the ETKAC for boys and girls, both of which were in a normal range, were 1.07+/-0.00 and 1.06+/-0.01, respectively. The respective prevalence rates of marginal and deficient thiamin states were 10.4% and 7.8% for boys and 9.3% and 7.3% for girls. Mean values of the EGRAC were 1.18+/-0.00 for boys and 1.19+/-0.01 for girls, both of which showed an increasing trend with age. The respective rates of marginal and deficient riboflavin states were as high as 32.5% and 3.5% for boys and 35.9% and 4.5% for girls. The marginal and deficient riboflavin statuses of Taiwanese schoolchildren were associated with a low frequency of dairy food consumption and an elevated risk of anemia.

B-vitamin status and concentrations of homocysteine in Austrian omnivores, vegetarians and vegans

BACKGROUND

A vegetarian diet is considered to promote health and longevity and reduce the risk of cardiovascular diseases and cancer. However, a vegetarian diet may be deficient in some nutrients. Exclusion of animal products in vegetarian diets may affect the status of certain B-vitamins, and further cause the rise of plasma homocysteine concentration.

OBJECTIVE

The nutritional status of various B-vitamins (B(1), B(2), B(6), B(12), folic acid) and the concentration of homocysteine in blood plasma of omnivores (n = 40), vegetarians (n = 36) and vegans (n = 42) in Austria was evaluated.

METHODS

The evaluation was done using the functional parameters erythrocyte transketolase (ETK), glutathione reductase (EGR) and glutamic oxaloacetic transaminase (EGOT) activation coefficients. Enzyme activity was measured photometrically. The quantity of vitamins B(1), B(2) and B(6) in urine and the concentrations of vitamin B(6) and homocysteine in plasma were determined by HPLC methods with fluorescence detection. Plasma concentration of vitamin B(12) and folic acid were measured with radioimmunoassay.

RESULTS

Most of the subjects showed a satisfying vitamin B(1) status. Vegans presented a significantly lower mean plasma vitamin B(12) concentration than omnivores and vegetarians and deficiency in 2.4% of the volunteers but the highest mean value of plasma folate among the investigated groups. A deficient status of folate was found in 18% of omnivores and in approximately 10% of vegans and vegetarians. The status of riboflavin is considered to be deficient in about 10% of omnivores and vegetarians and in over 30% of vegans. According to the activation coefficient of GOT, approximately one third of all subjects showed vitamin B(6) deficiency. Elevated homocysteine concentration in plasma was observed in 66% of the vegans and about 45-50% of the omnivores and vegetarians. Vegan subjects had significantly higher mean plasma homocysteine levels than omnivores.

CONCLUSION

Thiamin and folate need not be a problem in a well-planned vegan diet. Vitamins B(12) and B(2) may need attention in the strict vegan diet, especially regarding elevated homocysteine levels in plasma. Pyridoxine status appeared to be independent of the diet.

Prevalence of thiamin and riboflavin deficiency among the elderly in Taiwan

The purpose of this study was to perform biochemical assessments of the nutritional status of thiamin and riboflavin in the 2379 elderly persons (1213 males, 1166 females) participating in the Elderly Nutrition and Health Survey in Taiwan (1999-2000) (Elderly NAHSIT). Through analysis of the data we aimed to investigate possible factors related to the prevalence of vitamin deficiency. Activity coefficients of erythrocyte transketolase and glutathione reductase (ETKAC and EGRAC) were the chosen biochemical indicators for thiamin and riboflavin status. The results showed that 14.7% of men and 11.9% of women were marginally thiamin deficient, and 16.5% of men and 14% of women were thiamin deficient. The prevalence rates of marginal riboflavin deficiency were 25.7% for males and 20.1% for females, and the deficiency rates were 6.6% for elderly males and 4.1% for elderly females. Although the average dietary thiamin and riboflavin intakes reached 146%-164% of Taiwan RDAs, the percentage of senior citizens whose thiamin or riboflavin dietary intakes were less than EARs (equivalent to 83.3% of RDAs) was around 30% for males and 40% for females. Some contributing factors to the significant prevalence of thiamin and riboflavin deficiencies are discussed in this article.

[Thiamin and ribovlavin status in populations of Arkhangelsk]

It was been performed the epidemiological study of Thiamine and Riboflavin status of 3579 inhabitants in Arkhangelsk. Establish by 49.6% man and 47.4% woman have lower provision of thiamin. Lack of riboflavin reveal by 23.6% man and 21.7% woman. The analysis of the effect of seasonality on vitamins content shown the worst thiamin level in examined population in January-February and in September-October. The worst Riboflavin content observed in examined population in December-January and in July-August.

Normal riboflavin status in malaria patients in Gabon

Previous publications reported commonly the occurrence of riboflavin deficiency and a positive correlation between riboflavin status and parasitemia in patients with Plasmodium falciparum malaria. In these studies, riboflavin status was determined by erythrocyte glutathione reductase activation coefficients (EGRACs). Inherited low erythrocyte glutathione reductase activity is highly prevalent in malarial regions, however. To rule out falsely diagnosed riboflavin deficiency in affected patients, we conducted an investigation using a high-performance liquid chromatography method (HPLC) instead of the EGRAC method. In 29 infants (age range, 1-5 years), 22 schoolchildren (age range, 6-12 years), and 33 adolescents and adults (age range, 13-74 years) from Lambaréné, Gabon, with acute P. falciparum malaria, plasma concentrations of riboflavin, flavin mononucleotide (FMN), and flavin adenine dinucleotide (FAD) were measured by HPLC. Results were correlated with parasite densities. Profiles of plasma concentrations of all 3 flavin compounds were within the normal range in all patients. Concentrations of free riboflavin were not different between the 3 age groups. In adolescents and adults, FMN and FAD concentrations were higher than in infants (P = 0.002 and P = 0.001) and schoolchildren (P = 0.003 and P = 0.002). Comparing children with hyperparasitemic and uncomplicated malaria, no difference in the concentrations of either flavin compound was found. Neither the concentrations of free riboflavin nor the concentrations of one of the flavin nucleotides correlated with parasitemia within subgroups of age or of children with uncomplicated and hyperparasitemic malaria. Our data indicate that nutritional riboflavin deficiency might have been overestimated in previous malaria studies and do not support a relationship between flavin concentrations and parasitemia in P. falciparum malaria.

Angular stomatitis and riboflavin status among adolescent Bhutanese refugees living in southeastern Nepal

BACKGROUND

Between 1990 and 1993, fear of ethnic persecution led 83,000 ethnic Nepalese to flee from Bhutan to refugee camps in Nepal, where they remained at the time of this study. Reported cases of angular stomatitis (AS), ie, thinning or fissuring at the mouth angles, increased 6-fold from December 1998 to March 1999, from 5.5 to 35.6 cases per 1000 per month. This increase came after the removal of a fortified cereal from rations.

OBJECTIVES

The main objectives were to assess the prevalence of AS and of low concentrations of riboflavin, folate, vitamin B-12, and iron by using biochemical measures; to determine whether riboflavin status was associated with AS; and to assess the potential of AS as a screening measure for low riboflavin concentrations.

DESIGN

In October 1999, we performed a survey among a random sample of 463 adolescent refugees in which we conducted interviews and physical examinations and obtained blood specimens for riboflavin assessment. Riboflavin status was assessed with the erythrocyte glutathione reductase (EC 1.6.4.2) activity coefficient. After we excluded those adolescents who had taken vitamins during the past month, 369 were eligible for analyses.

RESULTS

AS was common (26.8%; 95% CI: 22.3, 31.3), the prevalence of low riboflavin concentrations was high (85.8%; 80.7, 90.9), and riboflavin status was associated with AS. Adolescents with AS had significantly lower riboflavin concentrations than did adolescents without AS (P = 0.02). The adjusted odds ratio for AS and low riboflavin concentrations was 5.1 (1.55, 16.5).

CONCLUSION

Globally, riboflavin deficiency is rare. Its emergence in food-dependent populations can be a harbinger of other B-vitamin deficiencies.

[Dietary and biochemical riboflavin status in a cohort of young people in the community of Madrid]

Riboflavin status was measured in 228 young people (101 women and 127 men) between 18 and 35 years of age, resident in the Comunidad Autónoma de Madrid. A dietetic study was undertaken using a three day food record (which included one non-working day). Also, biochemical levels of riboflavin were investigated via the determination of the activation coefficient of erythrocyte glutathione reductase (alpha-EGR). Although the mean intake of riboflavin was acceptable (107.1 +/- 29.1 of recommended intakes), 46.9 of subjects showed intakes below recommended. At the biochemical level, 14.9% of subjects showed a moderate risk of vitamin B2 deficiency (alpha-EGR: 1.2-1.4) whilst 1.3% were at high risk (alpha-EGR > 1.4). Male subjects showed higher alpha-EGR levels than did females, which coincides with their greater intake of vitamin B2. Milk products provided some 40.4% of the vitamin, meats 19.9%, cereals 8%, vegetables 7.2%, eggs 6.3%. Other foods provided lesser amounts. Therefore, although riboflavin is available across the food groups, it Would seem that milk products are its most important source. Indeed, subjects with high milk product intakes (more than one ration per day) showed the highest riboflavin levels and the most adequate alpha-EGR levels. This study shows that riboflavin status can be improved, especially amongst those with low milk product intakes. An increase in the consumption of these foods to recommended levels (2-3 rations per day) might improve this situation at both dietetic and biochemical levels.

Riboflavin deficiency and preeclampsia

OBJECTIVE

To examine in a prospective study riboflavin deficiency as a predisposing factor for preeclampsia in a high-risk collective of pregnant women in Zimbabwe.

METHODS

At an antenatal clinic in Bulawayo, Zimbabwe, 154 women at increased risk for preeclampsia were observed prospectively until delivery. Riboflavin status was determined using the erythrocyte glutathione reductase activation coefficient test on the day of antenatal booking. Riboflavin deficiency was expressed by erythrocyte glutathione reductase activation coefficient of 1.4 or greater.

RESULTS

Riboflavin deficiency was frequently found among the study population (33.8%). Incidence rose toward the end of pregnancy (27.3% at 29-36 weeks' gestation compared with 53.3% at over 36 weeks). In the riboflavin-deficient group, mothers were more likely to develop preeclampsia (28.8%) than in the riboflavin-adequate group (7.8%; P <.001, odds ratio [OR] 4.7, 95% confidence interval [CI] 1.8-12.2). The calculated concentrations of intracellular free flavin adenine dinucleotide were significantly lower in patients who developed preeclampsia than in normal pregnancies (P <.05).

CONCLUSION

Riboflavin deficiency should be considered a possible risk factor for preeclampsia. Insufficient concentrations of the riboflavin-derived cofactors flavin adenine dinucleotide and flavin adenine mononucleotide could contribute to the established pathophysiologic changes including mitochondrial dysfunction, enhanced oxidative stress, and disturbances in nitric oxide release.

[Erythrocyte glutathione reductase in pregnant women with hemoglobin AA and AS]

PURPOSE

To evaluate the catalytic activity of the red cell enzyme, glutathione reductase (GR) in pregnant women with Hb AS and with Hb AA, and in a group of non-pregnant women with Hb AA, as well as the relationship of GR deficiency with Hb S.

PATIENTS AND METHODS

The catalytic activity was determined in presence and absence of FAD by means of a modified Long and Carson technique. 59 pregnant women with AS and 33 with AA phenotypes were studied.

RESULTS

Differences were found in the enzyme's catalytic activity with and without FAD, both in pregnant women with Hb AS (mean values 37.17 nka/g y Hb in whites and 42.84 nkat/g HS in afro people) and in those with Hb AA, and also in non-pregnant women with Hb AA. A high frequency of GR deficiency was found in all groups due to an insufficient riboflavin supply in diet.

CONCLUSION

A correlation between GR deficiency and Hb S could not be demonstrated. The coefficient of activity of red cell GR shows a tendency to increase in pregnancy due to certain riboflavin deficit of diet.

The thiamin, riboflavin and pyridoxine status of patients on emergency admission to hospital

The aim of this study was to assess the prevalence of thiamin, riboflavin and pyridoxine deficiencies at admission to an acute hospital. One hundred and twenty adult patients were selected at random from those admitted via the Accident and Emergency department over 3 days. Comparisons were made with a group of 80 healthy blood donors sequentially attending a local transfusion centre. The alcohol intake of 500 patients admitted sequentially via the same Accident and Emergency department was also assessed. Erythrocyte transketolase (ETK), glutathione reductase (EGR) and aspartate aminotransferase (EAA) coenzyme activation assays were used to determine thiamin, riboflavin and pyridoxine deficiencies. The prevalences of deficiency states in the inpatient group were 21, 2.7 and 32% for thiamin, riboflavin and pyridoxine deficiencies respectively with 49.2% being deficient in one or more vitamin. The mean alcohol intake in the group of patients in whom this was assessed was 9.7 units per week compared with 10 units per week amongst blood donors.

Ageing, nutritional status and immune response

The effects of vitamin supplementation on the age-related decline in immune function was studied in a population of elderly subjects with a high prevalence of low and deficient serum values of vitamin C, vitamin E, riboflavin and pyridoxin, as well as iron and zinc. The immune function was examined by measuring delayed cutaneous hypersensitivity (DCH) after intradermal application of a set of 7 antigens in 72 subjects aged 60-89 years living in two homes for the elderly. The results showed an almost linear statistically significant decline in the DCH test with age (p < 0.01). Vitamin supplementation for a period of 10 weeks significantly improved the biochemical parameters for those vitamins and the age related decline in the DCH test was no longer statistically significant (P > 0.05). No statistically significant changes in DCH were observed in the placebo group. The results of this study suggest that nutrition may be an important determinant of immunocompetence in the elderly.

Vitamin B1, B2 and B6 deficiency in primary school children infected with hookworm

One thousand and seven hundred thirty-six school children from two districts in Nakhon Si Thammarat Province were screened for hookworm infection using the Kato-Katz stool examination technic. Two hundred students who have at least 2,000 eggs per g of stool were recruited into the program. The students were divided into six groups: groups 1, 2 and 3 were from Tha Sala district while groups 4, 5 and 6 were from Ronpibul district. Three milliliter blood samples were obtained from the cubital vein of each subject and were evaluated for erythrocyte transketolase activity (ETK) for vitamin B1, erythrocyte glutathione oxidoreductase activity (EGR) for vitamin B2, and erythrocyte aspartate aminotransferase activity (EAST) for vitamin B6. The school children were divided into three groups: those infected only with hookworm, those with both hookworm and Trichuris trichiura, and those whose stools show no parasite eggs. The results show that 10-20% of the school children are vitamin B1 deficient, about 40% to 80% are vitamin B2 deficient, and about 14% to 23% are vitamin B6 deficient. No correlation could be made between vitamin deficiencies and parasitic infection.

[Vitamin and mineral deficiency in Mexico. A critical review of the state of the art. II. Vitamin deficiency]

We carried out a review of the studies related to vitamin deficiencies in the Mexican population published since 1950. Forty four studies were published from which we can conclude that: a) dietary intake data suggest that ascorbic acid, riboflavin and retinol intake are deficient: reported intakes were 40-70%, 35-64% and 20-72% of the recommended daily amounts respectively; niacin intake was also deficient in some studies; b) about 10% of Mexican children in rural areas had deficient values of plasma retinol (< 100 ng/ml) and about 25 to 30% had low values (100-200 ng/ml); this prevalence is reduced in children with a higher socioeconomic level; c) some studies were found that show the existence of marginal deficiencies of vitamin E, riboflavin and vitamin B12 in apparently healthy populations. Further studies are required to identify the magnitude of these and perhaps other vitamin deficiencies and their potential effects on the health and function of the Mexican population.

Prevalence of riboflavin deficiency among Guatemalan elderly people and its relationship to milk intake

Six groups of elderly subjects from central Guatemala were assessed for riboflavin status by using the erythrocyte glutathione reductase activity coefficient (EGRAC). The prevalence of riboflavin deficiency ranged from 50% to 76% among the free-living rural elderly subjects. Milk intake data that were collected from some of the subjects showed a significant correlation (P < 0.0001) between frequency of milk intake and riboflavin status. In a short-term riboflavin supplementation experiment in which nine riboflavin-deficient subjects were given 10 mg riboflavin/d for 3 d, all the subjects' EGRACs were normalized by the supplementation. However, they returned to a state of deficiency within 2 wk while consuming their usual diets without supplementation. It appears that the high prevalence of riboflavin deficiency in elderly Guatemalan people is caused by inadequate intake of riboflavin-rich foods such as dairy products, and that sufficient amounts of riboflavin need to be ingested regularly to maintain satisfactory riboflavin status.

Low red blood cell glutathione reductase and pyridoxine phosphate oxidase activities not related to dietary riboflavin: selection by malaria?

This study was designed to confirm that low dietary riboflavin does not contribute to the flavin-deficient red blood cells commonly found in subjects in Ferrara Province, northern Italy. In this area it is primarily an inherited characteristic believed to have been selected for by malaria, which was endemic from the 12th century. In parallel with assessment of daily riboflavin intake (DRI), flavin adenine dinucleotide-dependent glutathione reductase (EGR) and flavin mononucleotide-dependent pyridoxine phosphate oxidase (PPO) were measured in beta-thalassemic heterozygotes, their normal relatives, and normal spouses (representative of the normal population). In all of these groups there is a high incidence of deficiency of these flavin enzymes. We found that the majority had an adequate riboflavin intake and there was no significant correlation of EGR and PPO activities with DRI. Thus, interpretation of low EGR activity is discussed with reference to studies of EGR done to detect nutritional riboflavin deficiency in countries where there is malnutrition and endemic malaria.

Interpretation of erythrocyte glutathione reductase activation test values for assessing riboflavin status

The erythrocyte glutathione reductase activation test (EGR-AC) is considered to be the best method to assess riboflavin nutritional status. Riboflavin supplementation studies carried out in India have raised doubts about the validity of currently available interpretive guidelines for interpreting the EGR-AC test. Changes in EGR-AC values in response to graded doses of riboflavin supplementation were investigated in schoolchildren, aged 7-11 years, belonging to the low-income group. For comparison, unsupplemented well-to-do schoolchildren of similar age group were also examined. The results of the study based on the measurement of EGR-AC by the procedure of Bayoumi and Rosalki (Clinical Chemistry, 1976, Vol. 22, pp. 327-335) with an incubation period of 15 min suggest that the cut-off value for EGR-AC to discriminate between riboflavin-deficient and normal children cannot be less than 1.5.

Enzymatic evaluation of riboflavin status of infants

Riboflavin status of solely breast-fed (SBF) infants aged 1-6 months (study 1) and solely or partially breast-fed (PBF) and weaned infants aged 6-24 months (study 2) was examined by the erythrocyte glutathione reductase activation test. Maternal riboflavin status and milk riboflavin content were also measured in study 1. Riboflavin status of the infants was significantly superior to that of their mothers. However, 35 per cent of SBF infants examined suffered from biochemical riboflavin deficiency as judged by the glutathione reductase test. Supplementary feeding of 6-8-month-old infants and weaning of older infants had positive effect on riboflavin status. There was no obvious relationship between riboflavin status and anthropometric status. Milk riboflavin concentration was comparable or only slightly lower than values reported for Western women, despite marked deficiency in the mothers.

Urinary riboflavin excretion after a load test in rural China as a measure of possible riboflavin deficiency

Urinary excretion of riboflavin was measured in 3318 adults 4 h after an oral dose of riboflavin. Male and female subjects aged 35-64 years were selected from 65 mostly rural counties located in 24 provinces of China. Counties were selected to represent a range of seven of the most prevalent cancer mortality rates in China and within counties households were selected at random. Urinary riboflavin excretion levels after a load test, erythrocyte glutathione reductase activity coefficients (EGR-AC), dietary riboflavin intakes, and a large number of other biochemical, dietary, and environmental parameters were measured. Mean dietary intake of riboflavin was 75 per cent of the Chinese recommended dietary allowances (CRDA). Mean meat intake per reference man was very low (26.4 +/- 23.7 g/d) in comparison to Western standards and milk was not consumed at all in most counties. Mean EGR activity coefficients measured on 'blood pools' for both males (1.47 +/- 0.14) and females (1.48 +/- 0.16) indicated that more than two-thirds of the population surveyed was in the medium or high risk category of riboflavin deficiency. Using current reference standards of less than 1.4 mg for 4-h urinary excretion of riboflavin after a 5 mg load, more than 70 per cent of the individuals examined exhibited low levels usually associated with high risk of riboflavin deficiency. In view of the lack of specificity for clinical indications of riboflavin deficiency and the tentative validity of the present CRDA, the interpretation of the data is problematic. We suggest that the present CRDA for this vitamin is set too high and requires critical review and possibly some revision.

Riboflavin status in urban adolescents

We compared riboflavin status in 284 healthy adolescents attending an urban university hospital clinic with that of 43 adolescents with a variety of chronic medical conditions. Riboflavin status was determined by erythrocyte glutathione reductase activity and 24-hour dietary recall of riboflavin intake. The mean activity coefficient for the healthy adolescents was 1.08 (SD +/- 0.09) and 1.10 (SD +/- 1.01) in the chronically ill group. Significantly higher values were found in females of both groups (z = 4.90, p less than 0.0001). Seventeen (7%) of the healthy teenagers and seven (16%) of the chronically ill group had biochemical evidence of riboflavin deficiency (p less than 0.02). Although the mean daily intake of riboflavin for the total group exceeded the recommended daily allowance, there was significantly lower riboflavin intake in the subgroup of adolescents who had abnormal activity coefficients (z = 3.29, p less than 0.001). These data suggest that subclinical riboflavin deficiency may occur in adolescents and that deficiency may be related to dietary intake of riboflavin.

[Riboflavin supply of the Kara-Kalpak ASSr population with pathologic changes of the esophageal mucosa]

Riboflavin supply was studied in 164 adult inhabitants of the Kara-Kalpak ASSR where a high incidence of cancer of the esophagus and precancer changes of the esophageal mucosa were recorded. Endoscopy was used to investigate the morphological picture of the esophageal mucosa. A standard method for evaluation of the activation coefficient (AC) of erythrocytic glutathion-reductase (EC1.6.4.2) in the presence of FAD was used as a criterion of the body supply with riboflavin. Pronounced riboflavin deficiency (AC greater than or equal to 1.30) and B2 hypovitaminosis (AC = 1.20-1.29) were observed in 17 and 23% of the cases, respectively. Statistical analysis of the data obtained evidences that insufficient supply with riboflavin is recorded, on an average, 3.5-5.5 times more frequently in subjects with pronounced catarrhal esophagitis, combined with or without leukoplakia, than in the control group of subjects with out pronounced changes in the esophageal mucosa. No positive statistically significant association between low supply of the body with riboflavin and atrophic esophagitis has been established.

Riboflavin status in Saudi Arabia--a comparative study in different regions

Riboflavin (vitamin B2) status was investigated in male and female Saudis of different age groups in different regions of Saudi Arabia using the assay of glutathione reductase (GR) in presence and absence of flavin adenine dinucleotide (FAD) and determination of the activity coefficient (AC) for GR. The overall prevalence of riboflavin deficiency as determined by an AC value of 1.3 or above, in the male population of Al-Hafouf, Jaizan and Riyadh was found to be 32.6%, 17.8% and 17.1%, respectively, while in the female population the prevalence was 41.5%, 22.3% and 37.9%, respectively. Within each region a marked variation was found in the different age groups. In this paper the riboflavin status and the prevalence of riboflavin deficiency in three regions of Saudi Arabia is presented and the possible causes for a high prevalence of riboflavin deficiency in the Saudi population are discussed.

Riboflavin status in a Saudi population--a study in Riyadh

Riboflavin is essential for several metabolic processes taking place in the human body. A deficiency of riboflavin has been reported to occur at a high prevalence in several populations, particularly in children and adolescents from low-socioeconomic groups. We investigated the riboflavin status in 502 Saudi males and 213 Saudi females using a determination of red-cell glutathione reductase activity in the presence and absence of flavin adenine dinucleotide. The population was grouped according to age and the glutathione reductase activity coefficient (AC) was calculated in each of the groups. An AC value of 1.3 or above was recorded in 38% of the females and 17% of the males. In the female group the lowest percentage was in girls less than 12 years of age, and the highest in the age group 21-30 years, while among males boys of less than 12 years and men over 30 years of age had the highest percentage. In this paper we report and discuss the riboflavin status, as indicated by the glutathione reductase AC, in the Saudi male and female population in the Riyadh area.

[Vitamin status of 11- to 17-year-old healthy adolescents. Data from a longitudinal study]

In order to find out whether any age- or sex-related changes in vitamin nutrition or if any vitamin deficiencies can be detected in apparently healthy school children, blood vitamins (A, B1, B2, B6, C, and E) were determined in 111 children (54 boys and 57 girls), who took part in a longitudinal nutritional program. Most of the adolescents were examined yearly 5 times every year and afterwards two years later; at the begin of the study their age was 11 years, at the end 17 years. The results of vitamin determinations show for the most parameters age dependent changes, levels for Vitamin A, B1, and B2 becoming higher with increasing age, for Vitamin C in contrast markedly unfavorable. Using the criteria for risk for deficiency from adults a comparatively high percentage of adolescents must be considered to be at risk for deficiency (up to 30% for Vitamin B6). As this study shows partly statistically significant correlations between growth and some vitamin levels (e.g., for Vitamin A and E), age and sex related criteria for the assessment of vitamin status in adolescents should be made available. The results in general show that also in apparently healthy school-children subclinical biochemical vitamin deficiencies can be detected. This fact however, should be taken in consideration in planing and providing guidelines for an optimal nutritional program in adolescence.

Nutritional status of a population assessed on the basis of a group of blood donors

Several blood constituents were used to evaluate the nutritional status of a random, consecutive group of 655 blood donors. The population included 503 men and 152 women, with a mean age of 35.1 years; 26.8% of the women and 26.5% of the men had deficient levels of ascorbic acid; 18.0% of the women an 11.9% of the men had hemoglobin levels below normal. Plasma iron was inadequate in 29.3% of the women and 18.6% of the men. A very small number of donors were found to be deficient in carotene, retinol, thiamine, riboflavin and pyridoxine. These findings call attention to an unexpected aspect of nutrition in an apparently healthy, not undernourished population.

Riboflavin status of adolescents in southern China. Average intake of riboflavin and clinical findings

The average riboflavin intake of 11 200 schoolchildren, aged 12-19 years, in Guangdong Province, China, was measured. Food intake was measured by weighing, and riboflavin intake was calculated by means of food tables. The average intake of riboflavin was 0.45 mg/day. In addition, clinical observations were made in 1313 adolescents in the dietary survey. The findings were consistent with the low intake of riboflavin. The observed clinical signs of riboflavin deficiency were scrotal dermatitis (7.9% of boys), angular stomatitis (5.8% of boys, 2.7% of girls), cheilosis (8.0% of boys, 5.6% of girls) and magenta tongue (36.0% of boys, 40.8% of girls). Corneal vascularization was found only in two of the 1313 children. Scrotal lesions resolved within three to six days after the oral administration of riboflavin (15 mg/day); the resolution of tongue and lip signs progressed more slowly.

Biochemical ariboflavinosis among Nigerian rural school children

Eighty school children (47 boys and 33 girls) from a rural community ranging in age from 10 to 16 years and of low socio-economic status were surveyed for riboflavin deficiency. The overall prevalence of subclinical riboflavin deficiency was 41 per cent based upon an activity coefficient (AC) of erythrocyte glutathione reductase (EGR) of more than 1.30. Although there was no significant difference in the overall prevalence of riboflavin deficiency between the boys and girls, the EGR-AC values correlated significantly with dietary riboflavin intake (r = -0.48, P less than 0.002) for the boys only. The regression analyses of riboflavin intake on EGR-AC values indicated that a minimum daily intake of 0.70 mg riboflavin or 0.4 mg/1000 kcal corresponded to acceptable EGR-AC values (less than 1.20) for the boys. Dietary data showed that the intake of energy, thiamine and riboflavin was grossly inadequate for the needs of the children. About 15 per cent of the total protein intake and 14.3 per cent of the total riboflavin intake were obtained from animal products with plant sources contributing the bulk of the intake. Milk intake was very low or non-existent. It is suggested that dietary intakes of large quantities of leafy vegetables and the use of fermented products and dried shrimps in the soup or an oral vitamin supplement would improve their riboflavin intake.

Riboflavin deficiency in Madang infants

83 healthy infants in Madang were screened for haematological variables and riboflavin status. 70 (84%) had evidence of riboflavin deficiency. It is suggested that pregnant and lactating women in this area may be deficient, and that riboflavin deficiency may protect infants against malaria.

Nutritional status in a healthy elderly population: riboflavin

Riboflavin status in 270 free-living and healthy elderly was determined from dietary intake (3-day food records) and erythrocyte glutathione reductase activity coefficients (EGR-AC). High EGR-ACs (greater than 1.35) indicate poor riboflavin nutriture. Mean dietary intakes of riboflavin were 1.86 +/- 0.64 (SD) for males and 1.58 +/- 0.69 mg/day for females. Approximately 45% of the population were taking some supplemental riboflavin and total riboflavin intakes ranged from 0.65 to 165 mg/day. The mean EGR-AC for those taking supplemental riboflavin was significantly lower than that of the nonsupplemented group (1.06 and 1.16, respectively). Only three subjects had EGR-ACs greater than 1.35. A significant correlation was found between total riboflavin intake and EGR-AC (r = 0.53). In a separate population of 667 volunteers between the ages of 20 and 87 yr, a significant decrease in mean EGR-AC with age was found. The mean EGR-AC for those over 60 yr and not taking a supplement was 1.16 +/ 0.10 compared to 1.23 +/- 0.11 for those from 20 to 29 yr old. Inadequate riboflavin nutriture appears to be more of a problem for younger than older adults.

Riboflavin requirements of lactating Gambian women: a controlled supplementation trial

As part of a study to determine the minimum allowance of riboflavin which is adequate for lactating women in a rural African environment, 60 subjects living in two Gambian villages were given either 2 mg riboflavin or a placebo daily on a double-blind basis for 12 wk. Their riboflavin intake from dietary sources was about 0.5 mg/day. In the supplemented group, the mean activation coefficient (AC) of erythrocyte glutathione reductase fell from 1.62 to 1.19 within 3 wk, and 90% had mean AC's below 1.3 throughout supplementation, whereas the placebo group maintained mean AC's between 1.6 and 1.9. Clinical signs associated with riboflavin deficiency improved more rapidly in the supplemented group; their breast milk riboflavin levels increased, and their infants' AC's were reduced, compared with those of the placebo group. After withdrawal of the supplement, the maternal and infants' AC's rose toward those of the placebo group. Thus a total riboflavin intake of about 2.5 mg/day during lactation is sufficient to maintain normal biochemical status in most Gambian women.

Vitamin B1, B2, B6, and C status in hospital inpatients

The status of vitamin B1, B2, B6 and C was investigated in 656 hospital inpatients by means of a dietary interview, biochemical studies, and clinical investigation. The daily intake was lower than the Recommended Dietary Allowance for vitamin B1 in 57%, B2 in 47%, B6 in 53%, and C in 9% of the patients; it was less than half the Recommended Dietary Allowance in 19, 12, 15, and 3%, respectively. A biochemical deficiency was observed in 25% of the patients for vitamin B1, in 11% for B2, in 25% for B6, and in 14% for C. On the basis of the parameters selected for this study, the biochemical vitamin status, the dietary vitamin intake, and the clinical symptoms correlated significantly with each other except in the case of vitamin B6.

Nutritional status of children, inmates of a small institution for homeless children in the capital of the State of S. Paulo, Brazil

Nutritional surveys (food consumption, clinical and biochemichal) were conducted in a small institution for homeless children. Results showed that only 30% of the children presented adequate calorie intake. Most of the children presented adequate protein intake, but almost half consumed less than 2/3 of the calcium RDA considered necessary. Food handling, processing, and distribution also proved inadequate and wastage, high. Skinfold measurement showed up one case of obesity. Furthermore, most of the children presented clinical signs of vitamin A deficiency, mostly skin lesions; while about half presented clinical signs of riboflavin deficiency. Biochemical data showed that 63.6% had deficient plasma levels of vitamin A, none showed abnormal results for riboflavin excretion, four showed packed blood cell volume below normal, and all had normal hemoglobin levels. Stool examinations revealed a high rate of pathogenic protozoa (Hymenolepis nana), in fact, one of the highest in Brazilian literature.