Subclinical Vitamin Research Articles

Prevalence of Vitamin D Deficiency and Associated Risk Factors in the US Population (2011-2012).

Introduction1,25-dihydroxyvitamin D3 (cholecalciferol), the hormonally active form of vitamin D3, is a lipid-soluble compound that plays a significant role in clinical medicine due to its potent effects on calcium homeostasis and bone metabolism. Since foods containing natural vitamin D are rare, the primary source of the compound remains its nonenzymatic dermal synthesis through exposure to ultraviolet rays in sunlight. Although uncommon in most developed countries, recent literature has demonstrated that subclinical vitamin D deficiency can exist in certain populations and plays a role in downstream clinical consequences, including cardiovascular disease, cancer, diabetes, osteoporosis, and fractures. This study aims to identify the prevalence and change in the pattern of vitamin D deficiency in subpopulations throughout the United States to provide a foundation for further clinical studies correlating the clinical outcomes to vitamin deficiency.MethodsData analyzed in this study were collected through National Health and Nutrition Examination Survey (NHANES), specifically from a population of 4962 participants, age ≥20 years, who were hospitalized between 2011 and 2012. This cohort was stratified to divide the population into patients that were vitamin D sufficient (>50 nmol/L) versus patients who were vitamin D deficient (50 nmol/L). The risk factors were compared between the subpopulations in 2005-2006 and 2011-2012.ConclusionsThe prevalence of vitamin D deficiency is greater in certain clinical subpopulations, and the presence of associated characteristics should raise the index of suspicion for the practicing clinician with regard to conditions associated with vitamin D deficiency, such as osteoporosis and osteomalacia. Further research investigating the pathophysiology of hypovitaminosis D and its clinical consequences can help better understand and prevent the development of associated comorbidities.

The Role of Vitamin B12 in the Management and Optimization of Treatment in Patients With Degenerative Cervical Myelopathy.

Study Design:Narrative review.Objectives:To discuss the relationship between degenerative cervical myelopathy (DCM) and vitamin B12 deficiency. Specifically, it is the aim to outline the rational for future research into assessment and therapeutic optimization of vitamin B12 in the treatment of DCM.Methods:Literature review.Results:DCM is the commonest cause of spinal cord impairment, with an average age of presentation in the sixth decade. Patients at this age have also been reported to have a high prevalence of vitamin B12 deficiency, with estimates of up to 20% in the elderly. Vitamin B12 deficiency can result in subacute combined degeneration of the spinal cord (SACD), and several case reports have pointed to patients with both DCM and SACD. Both SACD and reversible compressive injury due to DCM necessitate remyelination in the spinal cord, a process that requires adequate vitamin B12 levels. Basic science research on nerve crush injuries have shown that vitamin B12 levels are altered after nerve injury and that vitamin B12 along with dexamethasone or nonsteroidal anti-inflammatory drugs can reduce Wallerian degeneration. Furthermore, it has been suggested that a combination of B-vitamins can reduce glutamate-induced neurotoxicity.Conclusions:Given the high prevalence of clinical and subclinical vitamin B12 deficiency in the elderly, the role of vitamin B12 in myelination, and vitamin B12 deficiency as a differential diagnosis of DCM, it is important to investigate what role vitamin B12 levels play in patients with DCM in terms of baseline neurological function and whether optimization of vitamin B12 levels can improve surgical outcome. Furthermore, the routine assessment of vitamin B12 levels in patients considered for DCM surgery should be considered.

Prevalence of sub-clinical vitamin-D deficiency and hypothyroidism in children aged 18- 36 months with open anterior fontanelle: a cross-sectional study

Background: The range of normal closure time of the anterior fontanelle (AF) is generally regarded to be 4 to 26 months. The objectives of this study was to find out the prevalence of subclinical vitamin D deficiency and hypothyroidism in children aged 18-36 months with open AF.Methods: This is a hospital based, cross-sectional study done over a period of 24 months, in which thyroid function tests and 25-hydroxy-vitamin D levels were done for healthy children aged 18-36 months with open AF; the latter was also done for equal numbers (n=30) of age and sex matched children with closed AF for control values. The mean vitamin D levels and proportion of children of various categories based on vitamin D levels among both the groups were compared.Results: Open AF was seen in 37 children. Seven of them had obvious causes of delayed AF closure and were excluded. In the remaining 30 children, none of the children had abnormal thyroid function tests. 23.3% of the study group had low vitamin D levels; but, the levels were low even in 37% of control group. The mean vitamin D level of the study group (39.05±17.11 ng/ml) was similar to the control group (37.3±14.74 ng/ml).Conclusions: Neither subclinical vitamin D deficiency nor subclinical hypothyroidism accounted for delayed AF closure in this study.

Identification of vitamin B12 deficiency in vegetarian Indians.

The prevalence of a sub-clinical vitamin B12 deficiency in the vegetarians is high. Total serum vitamin B12 concentration alone does not reliably reflect vitamin B12 status. Holotranscobalamin (holo-TC) II is a bioactive B12 fraction promoting specific uptake of B12 by cells and the circulating concentration reflects the intake of B12, whereas total homocysteine (tHcy) indicates the metabolic ability. In this study, we investigated the diagnostic value of circulating holo-TC, B12, folate and homocysteine in vegetarians who were at risk of B12 deficiency. B12-related biomarkers were measured in 119 young, healthy graduate vegetarians. None was folate deficient. As per reported definition, half were B12 deficient; 70 % of males and 50 % of females had low plasma holo-TC concentrations; and 92 % of males and half of females had hyperhomocysteinaemia. None had any clinical signs of B12 deficiency. Receiver operating characteristic curve analysis demonstrated similar AUC at the B12 concentration of 100 and 150 pmol/l when holo-TC (0·777 and 0·784) and homocysteine (0·924 and 0·928) were used as variables. Cut-off value of 100 pmol/l resulted in the highest sensitivity of 77·78 % and specificity of 71·05 % with a predictive value of 19·6 pmol/l for holo-TC and a sensitivity of 82·72 % and specificity of 89·7 % with a predictive value of 21·7 µmol/l for homocysteine. The combination of B12, holo-TC and tHcy improves the diagnostic accuracy at these cut-offs, and we suggest that for the young Indian vegetarians the cut-off for plasma B12 and holotrancobalamin is 100 pmol/l and 19·6 pmol/l, respectively, and for homocysteine it is 17·6 (females) and 27 µmol/l (males) for identifying B12 deficiency.

Nutraceutical Properties of Bangladeshi Rice Varieties

Objectives: Prevalence of subclinical vitamin B12 deficiency is high during early pregnancy especially among Indian women. Early pregnancy is also associated with modulations in autonomic nervous activity to adapt to haemodynamic changes. Current study aimed to compare the autonomic nervous activity through heart rate variability (HRV) indices during early pregnancy in women with low and high vitamin B12 status. Methods: Forty-two healthy pregnant Indian women in their early pregnancy (<14 weeks) were evaluated. Blood samples were analysed for plasma vitamin B12, haemogram and ECG. ECG was subjected to heart rate variability analysis. Subjects were divided into four groups based on quartile values of vitamin B12 levels. Results: There was a significant difference in Log LF (low frequency) HRV between the study groups (p=0.03). Log LF HRV was lower in lowest vitamin B12 group (Quartile 1 of Vitamin B12 levels 248.7 pmol/L) (p=0.05). There was a significant positive correlation between plasma vitamin B12 levels and Log LF (r=0.36, p=0.02). Conclusion: This study showed reduced sympathetic activity among subjects with low vitamin B12 status compared to subjects with high vitamin B12 status. Thus, emphasising the use of vitamin B12 levels during routine clinical evaluation and utility of simple measures like HRV as a screening tool during pregnancy along with postural blood pressure evaluation to rule out orthostatic intolerance. Further, longitudinal studies are required to evaluate vitamin B12 status and its long-term impact on autonomic nervous system during pregnancy.

Nutraceutical Properties of Bangladeshi Rice Varieties

Objectives: Prevalence of subclinical vitamin B12 deficiency is high during early pregnancy especially among Indian women. Early pregnancy is also associated with modulations in autonomic nervous activity to adapt to haemodynamic changes. Current study aimed to compare the autonomic nervous activity through heart rate variability (HRV) indices during early pregnancy in women with low and high vitamin B12 status. Methods: Forty-two healthy pregnant Indian women in their early pregnancy (<14 weeks) were evaluated. Blood samples were analysed for plasma vitamin B12, haemogram and ECG. ECG was subjected to heart rate variability analysis. Subjects were divided into four groups based on quartile values of vitamin B12 levels. Results: There was a significant difference in Log LF (low frequency) HRV between the study groups (p=0.03). Log LF HRV was lower in lowest vitamin B12 group (Quartile 1 of Vitamin B12 levels 248.7 pmol/L) (p=0.05). There was a significant positive correlation between plasma vitamin B12 levels and Log LF (r=0.36, p=0.02). Conclusion: This study showed reduced sympathetic activity among subjects with low vitamin B12 status compared to subjects with high vitamin B12 status. Thus, emphasising the use of vitamin B12 levels during routine clinical evaluation and utility of simple measures like HRV as a screening tool during pregnancy along with postural blood pressure evaluation to rule out orthostatic intolerance. Further, longitudinal studies are required to evaluate vitamin B12 status and its long-term impact on autonomic nervous system during pregnancy.

Prevalence and Predictors of Subclinical Micronutrient Deficiency in German Older Adults: Results from the Population-Based KORA-Age Study.

Subclinical micronutrient deficiency in older adults is associated with chronic age-related diseases and adverse functional outcomes. In Germany, the older population is at risk of insufficient micronutrient intake, but representative studies on micronutrient status in old and very old adults are scarce. This study’s objectives were to estimate the prevalence of subclinical vitamin D, folate, vitamin B12 and iron deficiencies among older adults, aged 65 to 93, from the KORA-Age study in Augsburg, Germany (n = 1079), and to examine associated predictors, using multiple logistic regression. Serum concentrations of 25-hydroxyvitamin D (25OHD), folate, vitamin B12, and iron were analyzed. The prevalence of subclinical vitamin D and vitamin B12 deficiencies were high, with 52.0% and 27.3% of individuals having low 25OHD (<50 nmol/L) and low vitamin B12 concentrations (<221 pmol/L), respectively. Furthermore, 11.0% had low iron (men <11.6 µmol/L, women <9.0 µmol/L) and 8.7% had low folate levels (<13.6 nmol/L). Common predictors associated with subclinical micronutrient deficiency included very old age, physical inactivity, frailty and no/irregular use of supplements. Subclinical micronutrient deficiency is a public health concern among KORA-Age participants, especially for vitamins D and B12. The predictors identified provide further rationale for screening high-risk subgroups and developing targeted public health interventions to tackle prevailing micronutrient inadequacies among older adults.

The Human Serum Metabolome of Vitamin B-12 Deficiency and Repletion, and Associations with Neurological Function in Elderly Adults

The specific metabolomic perturbations that occur in vitamin B-12 deficiency, and their associations with neurological function, are not well characterized. We sought to characterize the human serum metabolome in subclinical vitamin B-12 deficiency and repletion. A before-and-after treatment study provided 1 injection of 10 mg vitamin B-12 (with 100 mg pyridoxine and 100 mg thiamin) to 27 community-dwelling elderly Chileans (∼74 y old) with vitamin B-12 deficiency, as evaluated with serum vitamin B-12, total plasma homocysteine (tHcy), methylmalonic acid (MMA), and holotranscobalamin. The combined indicator of vitamin B-12 status (cB-12) was computed. Targeted metabolites [166 acylcarnitines, amino acids, sugars, glycerophospholipids, and sphingolipids (liquid chromatography-tandem mass spectrometry)], and untargeted metabolites [247 chemical entities (gas chromatography time-of-flight mass spectrometry)] were measured at baseline and 4 mo after treatment. A peripheral nerve score was developed. Differences before and after treatment were examined. For targeted metabolomics, the data from 18 individuals with adequate vitamin B-12 status (selected from the same population) were added to the before-and-after treatment data set. Network visualizations and metabolic pathways are illustrated. The injection increased serum vitamin B-12, holotranscobalamin, and cB-12 (P < 0.001), and reduced tHcy and serum MMA (P < 0.001). Metabolomic changes from before to after treatment included increases (P < 0.001) in acylcarnitines, plasmalogens, and other phospholipids, whereas proline and other intermediaries of one-carbon metabolism-that is, methionine and cysteine-were reduced (P < 0.001). Direct significant correlations (P < 0.05 after the false discovery rate procedure) were identified between acylcarnitines, plasmalogens, phospholipids, lyso-phospholipids, and sphingomyelins compared with vitamin B-12 status and nerve function. Multiple connections were identified with primary metabolites (e.g., an inverse relation between vitamin B-12 markers and tryptophan, tyrosine, and pyruvic, succinic, and citric acids, and a direct correlation between the nerve score and arginine). The human serum metabolome in vitamin B-12 deficiency and the changes that occur after supplementation are characterized. Metabolomics revealed connections between vitamin B-12 status and serum metabolic markers of mitochondrial function, myelin integrity, oxidative stress, and peripheral nerve function, including some previously implicated in Alzheimer and Parkinson diseases. This trial was registered at www.controlled-trials.com as ISRCTN02694183.

Vitamin K2 supplementation and arterial stiffness among renal transplant recipients—a single-arm, single-center clinical trial

Subclinical vitamin K deficiency is prevalent among renal transplant recipients and is associated with an increased risk of cardiovascular disease. However, the association between vitamin K supplementation and improvement of arterial stiffness has not been explored in the renal transplant population. The KING trial (vitamin K2 In reNal Graft) is a single-arm study that evaluated the association between the change in vitamin K status and indices of arterial stiffness following 8 weeks of menaquinone-7 (vitamin K2) supplementation (360 μg once daily) among renal transplant recipients (n = 60). Arterial stiffness was measured using carotid-femoral pulse wave velocity (cfPWV). Subclinical vitamin K deficiency was defined as plasma concentration of dephosphorylated-uncarboxylated matrix Gla protein (dp-ucMGP) >500 pmol/L.At baseline, 53.3% of the study subjects had subclinical vitamin K deficiency. Supplementation was associated with a 14.2% reduction in mean cfPWV at 8 weeks (cfPWV pre-vitamin K2 = 9.8 ± 2.2 m/s vs. cfPWV post-vitamin K2 = 8.4 ± 1.5 m/s; P < .001). Mean dp-ucMGP concentrations were also significantly reduced by 55.1% following menaquinone-7 supplementation with a reduction in the prevalence of subclinical deficiency by 40% (P = .001). When controlled for age, durations of hemodialysis and transplantation, and the change in 24-hour mean arterial pressure, the improvement in arterial stiffness was independently associated with the reduction in dp-ucMGP concentration (P = .014).Among renal transplant recipients with stable graft function, vitamin K2 supplementation was associated with improvement in subclinical vitamin K deficiency and arterial stiffness. (Clinicaltrials.gov: NCT02517580).

ОСОБЛИВОСТІ ПРЕГРАВІДАРНОЇ ПІДГОТОВКИ ЖІНОК РІЗНИХ НАЦІОНАЛЬНОСТЕЙ

Мета дослідження – сформувати диференційний підхід щодо прегравідарної підготовки та ведення вагітності у жінок різних національностей.Матеріали та методи. Обстежено 120 жінок репродуктивного віку різних національностей: слов’янської (група І), в’єтнамської (група ІІ), китайської (група ІІІ), арабської (група ІV). Вивчали анамнестичні дані соматичного, сімейного, акушерсько-гінекологічного анамнезу. Визначали вміст фолієвої кислоти, ціанокобаламіну, вітаміну D загального.Результати дослідження та їх обговорення. У вітчизняних жінок захворювання серцево-судинної системи виявлено у 63,3 %, обмінно-ендокринні порушення – у 46,7 %, патологію шлунково-кишкового тракту – у 36,7 %. Від анемії страждали 66,7 % в’єтнамок, 70,0 % досліджуваних із арабських країн, захворювання сечовидільної системи були у 26,7 і 40,0 % пацієнток відповідно. В анамнезі мали пологи 53,3 % співвітчизниць, 63,3 % арабської, 50,0 % китайської і 33,3 % в’єтнамської національності. Медичні аборти були у 30,0 % вітчизняних жінок, у 6,7 % – китаянок. Спонтанні аборти у жінок в’єтнамської національності становили 26,7 %, безплідність – 23,3 %. У жінок в’єтнамської національності вторинна аменорея виявлена у 6,7 %, олігоменорея – у 16,7 %, при цьому недостатність лютеїнової фази – у 16,7 %. Низькі рівні фолієвої кислоти у крові обстежуваних становили від 26,7 до 53,5 %, ціанокобаламіну – від 3,4 до 16,7 %, вітаміну D – від 33,3 до 53,3 % випадків. Найбільш виразні відхилення від показників норми виявлено у жінок групи ІІ і групи ІІІ.Висновки. Прегравідарна підготовка й алгоритм ведення вагітних різних національностей має базуватися на індивідуальних особливостях їх організму. При плануванні вагітності слід визначати вміст фолієвої кислоти, ціанокобаламіну, вітаміну D у крові жінок з метою ранньої діагностики субклінічного гіповітамінозу та проведення профілактики можливих гестаційних ускладнень. У жінок із низьким вмістом фолієвої кислоти, ціанокобаламіну, вітаміну D у крові до вагітності доцільно контролювати їх рівень у першій і другій половині вагітності з метою своєчасної корекції.

Detection of subclinical vitamin K deficiency in neurosurgery with PIVKA-II

Vitamin K is known for supporting the carboxylation of hepatic coagulation proteins. Levels of proteins induced by vitamin K absence for factor II (PIVKA-II) reflect hypocarboxylated prothrombin and can be used to detect subclinical vitamin K deficiency. The aim of this study was to determine the prevalence of perioperative subclinical vitamin K deficiency among neurosurgical patients using PIVKA-II and investigate the existence of any correlation to standard coagulation assays. Also, the antitumor effects of vitamin K were reviewed. Thirty-five patients undergoing brain tumor resection were included. Blood samples were drawn preoperatively, at the end of surgery and in the morning after surgery. In addition to PIVKA-II, factor II and the Owren and Quick prothrombin times were analyzed. Seventeen of 35 patients had elevated PIVKA-II levels before surgery, which continued to be above normal range postoperatively. Median PIVKA-II and Owren prothrombin time (PT-INR) were increased on the morning day 1 postoperatively compared to before surgery, whereas Quick end-stage prothrombin time (EPT) decreased and factor II was unaffected. Postoperative complications were connected to high PIVKA-II increases. Positive correlations between PIVKA-II and factor II and body mass index (BMI) were found. In conclusion, PIVKA-II was increased in many patients preoperatively and then increased by the morning following surgery. Standard coagulation assays were largely non-pathological. Correlations were demonstrated between PIVKA-II and factor II and BMI. The effect of perioperative treatment with different vitamin K supplements should be investigated in future studies, as well as clinical trials evaluating their antitumor effects.

Subclinical Carotid Atherosclerosis and Vitamin D in Patients with Ankylosing Spondylitis

Subclinical Carotid Atherosclerosis and Vitamin D in Patients with Ankylosing Spondylitis

Vitamin A deficiency and determinants of vitamin A status in Bangladeshi children and women: findings of a national survey.

Using data from the national micronutrients survey 2011-2012, the present study explored the status of subclinical vitamin A nutrition and the underlying determinants in the Bangladeshi population. A nationwide cross-sectional study. Settings The survey covered 150 clusters; fifty in each of rural, urban and slum strata. Three population groups: (i) pre-school age children (6-59 months; PSAC); (ii) school age children (6-14 years; SAC); and (iii) non-pregnant non-lactating women (15-49 years; NPNLW). National prevalence of subclinical vitamin A deficiency was 20·5, 20·8 and 5·3 % in PSAC, SAC and NPNLW, respectively. Slum populations had higher prevalence compared with urban (PSAC: 38·1 v. 21·2 %, P0·05 for differences in β between <3 months v. 3-6 months, 6-9 months and 9-12 months). Prevalence of subclinical vitamin A deficiency was high in children in Bangladesh. Intakes of animal-source foods and leafy vegetables were associated with higher and lower retinol status, respectively. Increased food diversity through animal-source foods is required.

Subclinical Vitamin A Deficiency and Malnourishment among East Timor Refugee Children

Subclinical Vitamin A Deficiency and Malnourishment among East Timor Refugee Children

Vitamin K Metabolism in a Rat Model of Chronic Kidney Disease

Background: Patients with chronic kidney disease (CKD) have very high levels of uncarboxylated, inactive, extra-hepatic vitamin K-dependent proteins measured in circulation, putting them at risk for complications of vitamin K deficiency. The major form of vitamin K found in the liver is phylloquinone (K1). Menaquinone-4 (MK-4) is the form of vitamin K that is preferentially found in extra-hepatic tissues. Methods: In the present study, we assessed tissue concentrations of K1 and MK-4 and the expression of vitamin K-related genes in a rat model of adenine-induced CKD. Results: It was found that rats with both mild and severe CKD had significantly lower amounts of K1 measured in liver, spleen and heart and higher levels of MK-4 measured in kidney cortex and medulla. All animals treated with high dietary K1 had an increase in tissue levels of both K1 and MK-4; however, the relative increase in K1 differed suggesting that the conversion of K1 to MK-4 may be a regulated/limiting process in some tissues. There was a decrease in the thoracic aorta expression of vitamin K recycling (Vkor) and utilization (Ggcx) enzymes, and a decrease in the kidney level of vitamin K1 to MK-4 bioconversion enzyme Ubiad1 in CKD. Conclusion: Taken together, these findings suggest that CKD impacts vitamin K metabolism, and this occurs early in the disease course. Our findings that vitamin K metabolism is altered in the presence of CKD provides further support that sub-clinical vitamin K deficiency may represent a modifiable risk factor for vascular and bone health in this population.

The Persistent Problem of Malnutrition In India

India contributes to about a third of the total number of the under -nourished in the world. Generally, under-nutrition is assessed as under-weight or stunting and/or wasting. The Periodic surveys by the National Nutrition Monitoring Bureau (NNMB) and the National Family Health Survey (NFHS) reveal unacceptably high prevalence of under-weight and stunting among Indian children of 0-59 months of age. About 19% Indian children are born with low birth weight (<2500 g) due to chronic maternal under-nutrition. About a third of the rural adults also have chronic ener gy deficiency (BMI <18.5). Anaemia, as assessed by low haemoglobin, is widespread among the vulnerable segments of population. Calorie inadequacy, with or without protein inadequacy, is the predominant dietary problem and a lar ge majority of individuals consume less than 70% of the recommended dietary allowance of micronutrients. Though the periodic surveys by NNMB and/or NFHS indicate gradual reduction in under-nutrition over time, its prevalence is unacceptably high. However, all the nutrient intakes show a decline over the last four decades. Even if India achieves the WHO Assembly’s first of the six global nutrition targets of 40% reduction by 2025 in the extent of stunted in under-5 children, unacceptably high proportion of one in four children might still be stunted. Nutritional anaemia and sub-clinical vitamin A deficiency are widespread. Deficiencies of other micronutrients like riboflavin, folic acid, vitamin B 12 and vitamin D are also rampant. Among the adults, while there is a gradual reduction in chronic energy deficiency over the four decade follow-up period, there is also a gradual increase in overweight and obesity. Substantial increases in economic growth experienced over the past two decades did not translate into a similar substantial reduction in under -nutrition, perhaps due to unequal economic growth excluding the poor. Nutrition-sensitive interventions and programmes in agriculture, social safety nets, early child development, education, women’s empowerment and access to safe drinking water and sanitation have enormous potential to scale-up and enhance the effectiveness of nutrition-specific interventions.

P.1.h.024 - Behavioral changes and osteocalcin in an experimental model of subclinical vitamin K deficiency in rats

P.1.h.024 - Behavioral changes and osteocalcin in an experimental model of subclinical vitamin K deficiency in rats

Serum level of vitamin A in children with pneumonia aged less than 3 years

To investigate the association of the serum level of vitamin A (VA) with the severity of pneumonia and recurrent respiratory infection (RRI) within one year after treatment in children with pneumonia, and to provide a basis for serum VA level used as an index for judgment of the condition of pneumonia and prediction of the risk of recurrent respiratory infection. A total of 88 children with pneumonia aged less than 3 years were enrolled as study subjects. Serum VA level was measured on admission, and the development of RRI was followed up by telephone within 1 year after discharge. The children with pneumonia showed a reduction in the serum level of VA (0.8±0.3 μmol/L). The severe pneumonia group had a significantly lower serum level of VA than the mild pneumonia group (0.7±0.3 μmol/L vs 0.9±0.3 μmol/L; P<0.05), as well as a significantly higher detection rate of vitamin A deficiency (VAD) than the mild pneumonia group (63% vs 28%; P<0.05). The children were followed up for 1 year. The VAD-pneumonia group showed a significantly higher incidence of RRI than the normal VA-pneumonia group (49% vs 18%; P<0.05), while there were no significant differences in the incidence of RRI between the suspected subclinical vitamin A deficiency (SSVAD)-pneumonia group and the normal VA-pneumonia group, as well as between the VAD-pneumonia group and the SSVAD-pneumonia group (P>0.05). Children with pneumonia often have a low level of VA, and the level of VA is associated with the severity of pneumonia and the development of RRI afterwards.

Biomarkers and Algorithms for the Diagnosis of Vitamin B12 Deficiency.

Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In conjunction with total B12 and its bioactive protein-bound form, holo-transcobalamin (holo-TC), Hcy, and MMA are the preferred serum biomarkers utilized to determine B12 status. Clinically, vitamin B12 deficiency leads to neurological deterioration and megaloblastic anemia, and, if left untreated, to death. Subclinical vitamin B12 deficiency (usually defined as a total serum B12 of <200 pmol/L) presents asymptomatically or with rather subtle generic symptoms that oftentimes are mistakenly ascribed to unrelated disorders. Numerous studies have now established that serum vitamin B12 has limited diagnostic value as a stand-alone marker. Low serum levels of vitamin B12 not always represent deficiency, and likewise, severe functional deficiency of the micronutrient has been documented in the presence of normal and even high levels of serum vitamin B12. This review discusses the usefulness and limitations of current biomarkers of B12 status in newborn screening, infant and adult diagnostics, the algorithms utilized to diagnose B12 deficiency and unusual findings of vitamin B12 status in various human disorders.

Potential Role of Vegetarianism on Nutritional and Cardiovascular Status in Taiwanese Dialysis Patients: A Case-Control Study.

Background & ObjectivesCardiovascular disease remains the most common cause of death for patients on chronic dialysis. End stage renal disease patients undergoing dialysis imposed to reduce phosphorus intake, which likely contributes to development of vegetarian diet behaviors. Vegetarian diets are often lower in protein content, in contradiction to the recommendation that a high protein diet is followed by patients undergoing dialysis. The purpose of the study was to investigate the effects of a vegetarian diet on the nutritional and cardiovascular status of dialysis patients.Design, Setting, Participants, MeasurementsA study of 21 vegetarian dialysis patients and 42 age- and sex-matched non-vegetarian dialysis patients selected as controls was conducted in the Kaohsiung Veterans General Hospital. Brachial-ankle pulse wave velocity and biochemistry data including total homocysteine levels, serum lipid profiles, high-sensitivity C-reactive protein, vitamin D levels, albumin, and normalized protein catabolic rate were measured.ResultsCompared with the non-vegetarian control group, vegetarian subjects had lower body weight, body mass index, serum phosphate, blood urea nitrogen, serum creatinine, vitamin D, uric acid, albumin, and normalized protein catabolic rate (p < 0.05). The vegetarian group showed higher brachial-ankle pulse wave velocity than the non-vegetarian group (1926.95 ± 456.45 and 1684.82 ± 309.55 cm/sec, respectively, p < 0.05). After adjustment for age, albumin, pre-dialysis systolic blood pressure, and duration of dialysis, vegetarian diet remained an independent risk factor for brachial-ankle pulse wave velocity.ConclusionsThe present study revealed that patients on dialysis who follow vegetarian diets may experience subclinical protein malnutrition and vitamin D deficiency that could offset the beneficial cardiovascular effects of vegetarianism.