Vitamin B12 and folate and the risk of anemia in old age: the Leiden 85-Plus Study

Prevalence and determinants of micronutrient deficiencies in malnourished older hospitalized patients

BACKGROUND AND OBJECTIVE

Malnutrition and micronutrient deficiencies represent significant concerns in geriatric care, leading to adverse health outcomes in older adults. The study aimed to investigate the prevalence and determinants of micronutrient deficiencies in malnourished older hospitalized patients.

DESIGN AND SETTING

This prospective, observational study was conducted in a geriatric acute care unit.

PARTICIPANTS

The study included 156 malnourished older adults.

MEASUREMENTS

Malnutrition was identified using the Mini Nutritional Assessment-Short Form. Micronutrient status was assessed through serum analysis of vitamins (A, B1, B6, B12, C, D, E, H, K, folic acid) and minerals (iron, zinc, copper, selenium) within 24 h post-admission.

RESULTS

The average patient age was 82.3 ± 7.5 years, with 69% female. The results revealed a high prevalence of micronutrient deficiencies, with 90% of patients exhibiting deficiencies in three or more micronutrients. Notably, every patient presented at least one micronutrient deficiency. Common deficiencies were found in vitamins C (75%), D (65%), H (61%), and K (45%), as well as folic acid (37%), iron (31%), zinc (36%) and selenium (35%). In binary regression analysis, the amount of previous weight loss was significantly associated with a higher prevalence of multiple (>2) micronutrient deficiencies (P = 0.045). Other variables such age (P = 0.449), gender (P = 0.252), BMI (P = 0.265) and MNA-SF score (P = 0.200) did not show any significant association with the prevalence multiple micronutrient deficiencies.

CONCLUSION

The high prevalence of micronutrient deficiencies in malnourished older hospitalized patients underscore the urgent need for targeted interventions to address micronutrient deficiencies in this population, promoting their health status.

Vitamin B12 is associated negatively with anemia in older Chinese adults with a low dietary diversity level: evidence from the Healthy Ageing and Biomarkers Cohort Study (HABCS)

OBJECTIVE

The associations between plasma vitamin B12 level and anemia under different dietary patterns in elderly Chinese people are poorly understood. We aimed to examine the associations between plasma vitamin B12 levels and anemia under different dietary patterns in adults aged 65 years and older in nine longevity areas in China.

METHODS

A total of 2405 older adults completed a food frequency questionnaire at the same time as a face-to-face interview. The dietary diversity score (DDS) was assessed based on the food frequency questionnaire, with the low DDS group referring to participants with a DDS score ≤ 4 points. Vitamin B12 levels were divided into two groups of high (>295 pg/mL) and low (≤ 295 pg/mL) with the median used as the cut-off point. Sub-analyses were also performed on older adults divided into tertiles of vitamin B12 levels: low (< 277 pg/mL), medium (277-375 pg/mL) and high (> 375 pg/mL) to study the association of these levels with anemia.

RESULTS

Six hundred ninety-five (28.89%) of these people were diagnosed with anemia and had a mean age of 89.3 years. Higher vitamin B12 levels were associated with a decreased risk of anemia (multi-adjusted OR, 0.59, [95% CI, 0.45 ~ 0.77] P < 0.001) in older adults with a low DDS, whereas no significant association between vitamin B12 levels and anemia was found in older adults with a high DDS in a full-model after adjustment for various confounding factors (multi-adjusted OR, 0.88, [95% CI, 0.65 ~ 1.19], P = 0.41).

CONCLUSION

The relationship between vitamin B12 levels and the prevalence of anemia was significant only when the level of dietary diversity in the older adults was relatively low. The dietary structure of the population should be taken into consideration in combination in order to effectively improve anemia status by supplementing vitamin B12.

Nutritional Assessment of the Symptomatic Patient on a Plant-Based Diet: Seven Key Questions

Plant-based diets, both vegan and vegetarian, which emphasize grains, vegetables, fruits, legumes, nuts, and seeds are increasingly popular for health as well as financial, ethical, and religious reasons. The medical literature clearly demonstrates that whole food plant-based diets can be both nutritionally sufficient and medically beneficial. However, any person on an intentionally restrictive, but poorly-designed diet may predispose themselves to clinically-relevant nutritional deficiencies. For persons on a poorly-designed plant-based diet, deficiencies are possible in both macronutrients (protein, essential fatty acids) and micronutrients (vitamin B12, iron, calcium, zinc, and vitamin D). Practitioner evaluation of symptomatic patients on a plant-based diet requires special consideration of seven key nutrient concerns for plant-based diets. This article translates these concerns into seven practical questions that all practitioners can introduce into their patient assessments and clinical reasoning. Ideally, persons on plant-based diets should be able to answer these seven questions. Each serves as a heuristic prompt for both clinician and patient attentiveness to a complete diet. As such, these seven questions support increased patient nutrition knowledge and practitioner capacity to counsel, refer, and appropriately focus clinical resources.

The effects of single and a combination of determinants of anaemia in the very old: results from the TULIPS consortium

Background and objectives

Nutritional deficiencies, renal impairment and chronic inflammation are commonly mentioned determinants of anaemia. The aim of this study was to investigate the effects of these determinants, singly and in combination, on anaemia in the very old.

Method

The TULIPS Consortium consists of four population-based studies in oldest-old individuals: Leiden 85-plus Study, LiLACS NZ, Newcastle 85+ study, and TOOTH. Five selected determinants (iron, vitamin B12, and folate deficiency; low estimated glomerular filtration rate (eGFR); and high C-reactive protein (CRP)) were summed. This sum score was used to investigate the association with the presence and onset of anaemia (WHO definition). The individual study results were pooled using random-effects models.

Results

In the 2216 participants (59% female, 30% anaemia) at baseline, iron deficiency, low eGFR and high CRP were individually associated with the presence of anaemia. Low eGFR and high CRP were individually associated with the onset of anaemia.

In the cross-sectional analyses, an increase per additional determinant (adjusted OR 2.10 (95% CI 1.85–2.38)) and a combination of ≥2 determinants (OR 3.44 (95% CI 2.70–4.38)) were associated with the presence of anaemia. In the prospective analyses, an increase per additional determinant (adjusted HR 1.46 (95% CI 1.24–1.71)) and the presence of ≥2 determinants (HR 1.95 (95% CI 1.40–2.71)) were associated with the onset of anaemia.

Conclusion

Very old adults with a combination of determinants of anaemia have a higher risk of having, and of developing, anaemia. Further research is recommended to explore causality and clinical relevance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02389-2.

No association between subnormal serum vitamin B12 and anemia in older nursing home patients

PURPOSE

Since evidence of an association between vitamin B12 (B12) deficiency and anemia in older people is limited and inconclusive, we wanted to investigate this association in old, frail nursing home patients.

METHODS

The study includes patients admitted to short-term, post-acute care (n = 765) and residents in long-term care (LTC) (n = 1665), in the municipality of Bergen. Anemia was defined according to the WHO criteria: Hb < 13 g/dL in men and < 12 g/dL in women, and as Hb < 11 g/dL, in both sex (moderate/severe anemia). The presence of anemia was analyzed in patients with subnormal (< 250 pmol/L), normal (250-650 pmol/L) and high (> 650 pmol/L) B12, and the association between anemia and clinical parameters, and including B12, was analyzed using logistic regression models. The use of B12 supplementation was investigated in the LTC patients.

RESULTS

Mean age of the 2430 patients was 86 ± 7 years. WHO-defined anemia was seen in 1023 (42%), and moderate/severe anemia in 384 (16%) of the patients. In multiple logistic regression analyses, we found no statistically significant associations of subnormal B12 with WHO-defined anemia or moderate/severe anemia. Renal insufficiency, iron deficiency and CRP > 10 mg/L were significantly associated with both types of anemia, (p < 0.001). Among the LTC residents, 405 (24%) received B12 supplements, 112 (7%) of them had elevated B12 > 650 pmol/L.

CONCLUSION

In older nursing home patients, no association was observed between subnormal B12 and anemia. Older patients in Western societies with mild/moderate anemia should not be treated with B12 supplements without further investigation.

Review of clinical nerve repair strategies for neurorestoration of central nervous system tumor damage

Central nervous system (CNS) tumors are common. In recent years, with the continuous development and popularization of neurosurgery and the advancement of diagnostic and therapeutic instruments, the diagnosis and treatment of diseases have made great progress, but the prognosis of patients depends on multiple clinical factors. In this study, we selected various literatures in the PubMed and Google Scholar search engines using the keywords "nerve repair strategies" , "central nervous system tumor" as well as searched scientifically reviewed historical perspectives and recent advancements and achievements in Neurorestoratology of the CNS. Therefore, this study focuses on the Neurorestoratology of the CNS and its prospects, aiming to provide scientific guidance for the clinical diagnosis and treatment of CNS tumors in the future, and improve the prognosis and quality of life of patients.

Exercise and metformin counteract altered mitochondrial function in the insulin-resistant brain

Insulin resistance associates with increased risk for cognitive decline and dementia; however, the underpinning mechanisms for this increased risk remain to be fully defined. As insulin resistance impairs mitochondrial oxidative metabolism and increases ROS in skeletal muscle, we considered whether similar events occur in the brain, which - like muscle - is rich in insulin receptors and mitochondria. We show that high-fat diet-induced (HFD-induced) brain insulin resistance in mice decreased mitochondrial ATP production rate and oxidative enzyme activities in brain regions rich in insulin receptors. HFD increased ROS emission and reduced antioxidant enzyme activities, with the concurrent accumulation of oxidatively damaged mitochondrial proteins and increased mitochondrial fission. Improvement of insulin sensitivity by both aerobic exercise and metformin ameliorated HFD-induced abnormalities. Moreover, insulin-induced enhancement of ATP production in primary cortical neurons and astrocytes was counteracted by the insulin receptor antagonist S961, demonstrating a direct effect of insulin resistance on brain mitochondria. Further, intranasal S961 administration prevented exercise-induced improvements in ATP production and ROS emission during HFD, supporting that exercise enhances brain mitochondrial function by improving insulin action. These results support that insulin sensitizing by exercise and metformin restores brain mitochondrial function in insulin-resistant states.

Rapid testing of red blood cell parameters in primary care patients using HemoScreen™ point of care instrument

Background

Patients with anemia are frequently encountered in primary care. Once anemia is detected, it is essential to define the type and identify the underlying cause prior to initiation of treatment. In most cases, the cause can be determined using information from the patient history, physical exam, and complete blood counts (CBC). Point of care testing of blood cell counts would speed up the work up of anemia patients. The aim of the present study was to evaluate if the HemoScreen™ instrument (PixCell Medical, Yokneam Ilit, Israel) could be used for primary care samples. It is a POCT instrument that utilizes single sample cuvettes and image analysis of full blood count including RBC, Hemoglobin, MCV, MCH, platelets, WBC, and WBC 5-part differential.

Methods

We compared the HemoScreen™ and the Sysmex XN instrument results of 100 primary care patient samples focusing on the total white blood cells, red blood cell parameters RBC, Hemoglobin, MCH, MCV and platelets.

Results

Deming correlations between the HemoScreen™ and the Sysmex XN instruments for the CBC were WBC_{HemoScreen™} = 1.016* WBC_Sysmex + 0.34; r = 0.981, RBC_{HemoScreen™} = 0.988* RBC_Sysmex + 0.015; r = 0.974, Hemoglobin_{HemoScreen™} = 1.081* Hemoglobin_Sysmex − 11.25; r = 0.964, MCH_{HemoScreen™} = 0.978* MCH_Sysmex + 0.78; r = 0.939, MCV_{HemoScreen™} = 0.963* MCV_Sysmex + 8.68; r = 0.946, Platelets_{HemoScreen™} = 0.964* Platelets_Sysmex + 25.7; r = 0.953.

Conclusion

The HemoScreen™ instrument could provide rapid and accurate test results for evaluation of the red blood cell parameters in primary care. This new technology is interesting as it allows the analysis red blood cell parameters also at small primary care centers.

The Many Faces of Cobalamin (Vitamin B12) Deficiency

Although cobalamin (vitamin B₁₂) deficiency was described over a century ago, it is still difficult to establish the correct diagnosis and prescribe the right treatment. Symptoms related to vitamin B₁₂ deficiency may be diverse and vary from neurologic to psychiatric. A number of individuals with vitamin B₁₂ deficiency may present with the classic megaloblastic anemia.

In clinical practice, many cases of vitamin B₁₂ deficiency are overlooked or sometimes even misdiagnosed. In this review, we describe the heterogeneous disease spectrum of patients with vitamin B₁₂ deficiency in whom the diagnosis was either based on low serum B₁₂ levels, elevated biomarkers like methylmalonic acid and/or homocysteine, or the improvement of clinical symptoms after the institution of parenteral vitamin B₁₂ therapy. We discuss the possible clinical signs and symptoms of patients with B₁₂ deficiency and the various pitfalls of diagnosis and treatment.

Prevalence of Nutritional Anemia and Hyperhomocysteinemia in Urban Elderly

The data on the prevalence of nutritional anemia among the urban elderly population in India was limited. Hence, the present study was carried out with an aim to assess the prevalence of nutritional anemia and its association with vitamin B12, folate, ferritin and homocystine among the urban elderly population. A community- based cross-sectional study was carried out among 282 urban elderly (≥ 60 years) subjects (186 males and 96 females) in Hyderabad. Fasting blood samples were collected and hemoglobin (Hb) was estimated by cyanmethemoglobin method. Plasma Folic acid and vitamin B12 levels were estimated by RIA and homocysteine and ferritin levels were estimated by ELISA methods. The overall prevalence of anemia (Hb < 12 g/dL for females and < 13 g/dL for males) among the urban elderly was 20.6% and the prevalence was found to be increasing with the age. The prevalence of vitamin B12 (< 203 pg/mL), folic acid (< 4 ng/mL), ferritin (< 15 ng/mL) and hyperhomocysteinemia (≥ 12 µmol/L) in these subjects was 36.0%, 8.2%, 1.1% and 24.3% respectively. The prevalence of anemia due to deficiencies of iron (ferritin < 15 ng/mL), folate and vitamin B12 was 5.45%, 9.1% and 42.3% respectively. A significant association was observed between the prevalence of anemia with ferritin and hyperhomocysteinemia. In conclusion, the prevalence of anemia and nutritional anemia among the urban-based elderly was 20.6% and 56.85% respectively. The association of anemia with hyperhomocysteinemia needs further studies.

The effect of vitamin B12 and folic acid supplementation on routine haematological parameters in older people: an individual participant data meta-analysis

BACKGROUND/OBJECTIVES

Low vitamin B12 and folate levels in community-dwelling older people are usually corrected with supplements. However, the effect of this supplementation on haematological parameters in older persons is not known. Therefore, we executed a systematic review and individual participant data meta-analysis of randomised placebo-controlled trials (RCTs).

SUBJECTS/METHODS

We performed a systematic search in PubMed, EMBASE, Web of Science, Cochrane and CENTRAL for RCTs published between January 1950 and April 2016, where community-dwelling elderly (60+ years) who were treated with vitamin B12 or folic acid or placebo. The presence of anaemia was not required. We analysed the data on haematological parameters with a two-stage IPD meta-analysis.

RESULTS

We found 494 full papers covering 14 studies. Data were shared by the authors of four RCTs comparing vitamin B12 with placebo (n = 343) and of three RCTs comparing folic acid with placebo (n = 929). We found no effect of vitamin B12 supplementation on haemoglobin (change 0.00 g/dL, 95% CI: -0.19;0.18), and no effect of folic acid supplementation (change -0.09 g/dL, 95% CI: -0.19;0.01). The effects of supplementation on other haematological parameters were similar. The effects did not differ by sex or by age group. Also, no effect was found in a subgroup of patients with anaemia and a subgroup of patients who were treated >4 weeks.

CONCLUSIONS

Evidence on the effects of supplementation of low concentrations of vitamin B12 and folate on haematological parameters in community-dwelling older people is inconclusive. Further research is needed before firm recommendations can be made concerning the supplementation of vitamin B12 and folate.

The Influence of Malnutrition and Micronutrient Status on Anemic Risk in Children under 3 Years Old in Poor Areas in China

BACKGROUND

Malnutrition and anemia affect large numbers of young children living in poor areas of China. Multi-micronutrient deficiencies may be related to the prevalence of anemia in different populations, and identifying the risk factors that render children susceptible to anemia is the first step in combating anemia effectively.

METHODS

In this cross-sectional study, a total of 1370 children under 3 years old were selected based on probability proportional to size sampling principles from poor counties of China. Basic characteristics data were collected by questionnaire; then anthropometrics and hemoglobin were measured in the field and anemia prevalence evaluated. Venous blood was drawn from children aged 12-35 months (N = 553) to evaluate micronutrient status. Logistic regression was used to identify the risk factors for children's anemia.

RESULTS

Among children aged 0-35 months, the prevalence of stunting, low body weight and wasting was 17.5%, 8.6% and 5.1%, respectively, and 25.6% of the children were affected by anemia, with more anemic infants and younger children than older children (P <0.01). There were 26.5%, 12.8%, 14.1% and 20.0% of the children aged 12-35 months affected by iron deficiency, vitamin D deficiency, folic acid deficiency and vitamin B12 deficiency, respectively. For children aged 0-11 months who were breastfed, the mothers' anemic status was the only factor associated with the child's anemia (OR = 2.6; 95% CI: 1.2-5.4, P < 0.05). For children aged 12-35 months, multivariate logistic regression indicated that anemia was significantly associated with iron and vitamin B12 deficiency (OR = 5.3; 95% CI: 1.9-14.5, P < 0.01) and monotonous diet (OR = 2.3; 95% CI: 1.1-4.7, P < 0.05) after adjusting for age and gender.

CONCLUSION

The prevalence of anemia was higher in children under 2 years old and requires urgent intervention. An effective intervention strategy should include iron and vitamin B12 supplements, improving dietary diversity and controlling breastfeeding mothers' anemia.

Prevalence and possible causes of anemia in the elderly: a cross-sectional analysis of a large European university hospital cohort

Background

Anemia in later life is associated with increased morbidity and mortality. The purpose of this study was to evaluate the prevalence and possible causes of anemia in the elderly in a well defined hospital cohort.

Methods

Participants in this cross-sectional, retrospective analysis included all inpatients and outpatients aged ≥64 years with complete blood counts treated at Innsbruck Medical University Hospital between October 1, 2004 and September 29, 2005 (n=19,758, median age 73 years).

Results

According to World Health Organization criteria, 21.1% of these patients were anemic, ie, 30.7% and 37.0% at 80+ years and 90+ years, respectively. The prevalence of anemia was significantly correlated with advanced age (r=0.21; P<0.001) and male sex (P<0.001). In anemic patients, renal insufficiency with a glomerular filtration rate <30 mL/min/1.73 m² (11.3% versus 2.1%), hyperinflammation (62.1% versus 31.4%), absolute (14.4% versus 6.9%) or functional (28.2% versus 11.8%) iron deficiency, and folate deficiency (6.7% versus 3.0%) were observed significantly more often than in nonanemic subjects (P<0.001). The pathogenesis of anemia was multifactorial, with decreased renal function (glomerular filtration rate <60 mL/min/1.73 m²), signs of inflammation, and functional iron deficiency detected in 11.4% of anemic patients. Hemoglobin was significantly correlated with elevated C-reactive protein (r= −0.296; P<0.001) and low transferrin saturation (r=0.313; P<0.001). Mean corpuscular volume correlated only weakly with the various anemia subtypes. Cytopenias and morphologic alterations suggestive of underlying myelodysplastic syndromes were found in a substantial proportion of anemic patients, including thrombocytopenia (5.4%), leukopenia (8.26%), and macrocytic alterations (18.4%).

Conclusion

Anemia was frequently diagnosed in this series of elderly patients. Partly treatable nutritional deficiencies, such as iron or folate deficiency, were identified as possible causes. A complex and heterogeneous interplay of chronic inflammation, functional iron deficiency, and renal impairment was identified in a large proportion of patients. A hitherto undiagnosed myelodysplastic syndrome can be assumed in a relevant proportion of patients. Morphologic classification based on mean corpuscular volume is inadequate from the standpoint of pathogenesis. New parameters are needed to differentiate the multifactorial pathogenesis of anemia in the elderly.

Homocysteine and vitamin B12 status and iron deficiency anemia in female university students from Gaza Strip, Palestine

OBJECTIVE

Nutritional deficiencies are very significant to the overall health of humans at all ages and for both genders, yet in infants, children and women of childbearing age these deficiencies can seriously affect growth and development. The present work is aimed to assess homocysteine and vitamin B12 status in females with iron deficiency anemia from the Gaza Strip.

METHODS

Venous blood samples were randomly collected from 240 female university students (18-22 years old) and parameters of the complete blood count, serum ferritin, homocysteine and vitamin B12 were measured. Statistical analysis included the t-test and analysis of variance (ANOVA) using the IBM SPSS software (version 18). Statistical significance was set for p-values <0.05.

RESULTS

The results revealed that 20.4% of the students have iron deficiency anemia. The mean serum vitamin B12 level in females with iron deficiency anemia (212.9±62.8pg/mL) was significantly lower than in normal controls (286.9±57.1pg/mL) and subjects with microcytic anemia and normal ferritin (256.7±71.1pg/mL). Significantly higher serum homocysteine levels were reported in the iron deficiency anemia group (27.0±4.6μmol/L) compared to normal controls (15.5±2.9μmol/L) and in subjects with microcytic anemia and normal ferritin (18.1±2.7μmol/L). Statistically significant negative correlations were reported for serum homocysteine with serum ferritin, vitamin B12, hemoglobin, and hematocrit levels.

CONCLUSION

Important associations were found between serum homocysteine and markers of iron deficiency. Monitoring homocysteine levels might be essential to understand the development of different clinical conditions including anemia. It seems necessary to conduct prospective trials to determine whether treating anemia ameliorates homocysteine levels.

[Gender aspects of malnutrition and associated sequelae. Prevention and therapy]

Malnutrition is related to a range of secondary complications. The prevalence of many of these sequelae is higher in elderly women than in men, thus resulting in a higher level of impairment and reduced quality of life. Multiple factors lead to the development of malnutrition and socioeconomic causes, such as poverty among the elderly and isolation, are more common in elderly women. The age-associated loss of muscle mass is more pronounced in women than in men and the risk of developing sarcopenia and frailty is increased. The prevalence of sarcopenic obesity is higher in women than in men. Malnutrition increases the risk of osteoporosis and about 80 % of all osteoporosis patients are women. Furthermore, low serum levels of vitamin D correlate more closely to a poorer cognitive outcome in elderly women than they do in men. The prevention, early diagnosis and therapy of malnutrition is of great clinical importance, particularly to preserve physical functional capacity and thus quality of life in elderly women.

Plasma hepcidin levels and anemia in old age. The Leiden 85-Plus Study

Hepcidin, an important regulator of iron homeostasis, is suggested to be causally related to anemia of inflammation. The aim of this study was to explore the role of plasma hepcidin in anemia among older persons from the general population. The Leiden 85-Plus Study is a population-based study of 85-year olds in Leiden, the Netherlands. Eighty-five-year old inhabitants of Leiden were enrolled between September 1997 and September 1999. At the age of 86, plasma hepcidin was determined with time of flight mass spectrometry in 490 participants [160 (32.7%) male, 114 (23.3%) with anemia]. Anemia was defined according to criteria of the World Health Organization (hemoglobin level <13 g/dL for men and hemoglobin <12 g/dL for women). The median plasma hepcidin level was 3.0 nM [interquartile range (IQR) 1.8-4.9]. We found strong correlations between plasma hepcidin and body iron status, C-reactive protein and erythropoietin levels. Significantly higher hepcidin levels were found in participants with anemia of inflammation (P<0.01), in participants with anemia of kidney disease (P=0.01), and in participants with unexplained anemia (P=0.01) than in participants without anemia. Participants with iron-deficiency anemia had significantly lower plasma hepcidin levels than participants without anemia (P<0.01). In conclusion, older persons with anemia of inflammation have higher hepcidin levels than their counterparts without anemia. The potential clinical value of hepcidin in future diagnostic algorithms for anemia has to be explored.

No increased mortality risk in older persons with unexplained anaemia

BACKGROUND

in older persons, anaemia is associated with a number of unfavourable outcomes. In approximately 30% of older persons with anaemia, the cause of the anaemia is unexplained. We assessed the clinical differences between subjects with explained and unexplained anaemia and investigated whether these subjects have different mortality patterns compared with subjects without anaemia.

DESIGN

observational prospective follow-up study.

SETTING

the Leiden 85-plus study.

PARTICIPANTS

four hundred and ninety-one persons aged 86 years.

METHODS

the study population was divided in three groups: (i) no anaemia (reference group, n=377), (ii) explained anaemia (iron deficiency, folate deficiency, vitamin B12 deficiency, signs of myelodysplastic syndrome or renal failure, n=74) and (iii) unexplained anaemia, (n=40). Mortality risks were estimated with Cox-proportional hazard models.

RESULTS

haemoglobin levels were significantly lower in subjects with explained anaemia than in subjects with unexplained anaemia (P<0.01). An increased risk for mortality was observed in subjects with explained anaemia [HR: 1.93 (95% CI: 1.47-2.52), P<0.001], but not in subjects with unexplained anaemia [HR: 1.19 (95% CI: 0.85-1.69), P=0.31]. Adjusted analyses (sex, co-morbidity, MMSE, institutionalised and smoking) did not change the observed associations for both explained and unexplained anaemic subjects.

CONCLUSION

older subjects with unexplained anaemia had similar survival compared with non-anaemic subjects. Increased mortality risks were observed in subjects with explained anaemia compared with non-anaemic subjects.

Vitamin B12 deficiency in Australian residential aged care facilities

OBJECTIVE

To determine the prevalence of undiagnosed vitamin B12 deficiency among residential aged care facility residents in southern Tasmania, Australia, and to identify associated risk factors.

DESIGN AND SETTING

Cross-sectional study of residents from five southern Tasmanian residential aged care facilities.

PARTICIPANTS

Two hundred and fifty-nine residents without a prior diagnosis of vitamin B12 deficiency or recorded serum B12 level within the past 6 months were approached to have their serum B12 level tested. One hundred and sixty (61%) residents consented and their doctors were contacted for further consent. A total of 130 (50%) residents completed the study.

MEASUREMENTS

Clinical and demographic characteristics, and serum B12 level.

RESULTS

Of the 130 residents tested, 18 residents (14%) were considered vitamin B12 deficient (serum level <150 pmol/L), 47 (36%) were equivocal (150 pmol/L to 250 pmol/L) and 65 (50%) had normal serum B12 levels (>250 pmol/L). There was a weak negative correlation between age and serum B12 level in those residents not taking a multivitamin (n=120, r=-0.19, p<0.05). The use of a multivitamin or antipsychotic drug were associated with altered mean serum B12 levels (+137 pmol/L, p<0.001 and -70 pmol/L, p<0.001 respectively).

CONCLUSION

As vitamin B12 deficiency can manifest in a range of symptoms that are frequently misdiagnosed, the finding of undetected deficiency in 14% of residents is a cause for concern. Oral multivitamin supplementation may help prevent deficiency, and potentially treat existing deficiencies in older institutionalised people.

Serum concentrations of vitamin B12 and folate in British male omnivores, vegetarians and vegans: results from a cross-sectional analysis of the EPIC-Oxford cohort study

BACKGROUND/OBJECTIVES

Vegans, and to a lesser extent vegetarians, have low average circulating concentrations of vitamin B12; however, the relation between factors such as age or time on these diets and vitamin B12 concentrations is not clear. The objectives of this study were to investigate differences in serum vitamin B12 and folate concentrations between omnivores, vegetarians and vegans and to ascertain whether vitamin B12 concentrations differed by age and time on the diet.

SUBJECTS/METHODS

A cross-sectional analysis involving 689 men (226 omnivores, 231 vegetarians and 232 vegans) from the European Prospective Investigation into Cancer and Nutrition Oxford cohort.

RESULTS

Mean serum vitamin B12 was highest among omnivores (281, 95% CI: 270-292 pmol/l), intermediate among vegetarians (182, 95% CI: 175-189 pmol/l) and lowest among vegans (122, 95% CI: 117-127 pmol/l). In all, 52% of vegans, 7% of vegetarians and one omnivore were classified as vitamin B12 deficient (defined as serum vitamin B12 <118 pmol/l). There was no significant association between age or duration of adherence to a vegetarian or a vegan diet and serum vitamin B12. In contrast, folate concentrations were highest among vegans, intermediate among vegetarians and lowest among omnivores, but only two men (both omnivores) were categorized as folate deficient (defined as serum folate <6.3 nmol/l).

CONCLUSION

Vegans have lower vitamin B12 concentrations, but higher folate concentrations, than vegetarians and omnivores. Half of the vegans were categorized as vitamin B12 deficient and would be expected to have a higher risk of developing clinical symptoms related to vitamin B12 deficiency.

Subnormal vitamin B12 concentrations and anaemia in older people: a systematic review

BACKGROUND

Pernicious anaemia is undeniably associated with vitamin B12 deficiency, but the association between subnormal vitamin B12 concentrations and anaemia in older people is unclear. The aim of this systematic review was to evaluate the association between subnormal vitamin B12 concentrations and anaemia in older people.

METHODS

Clinical queries for aetiology and treatment in bibliographic databases (PubMed [01/1949-10/2009]; EMBASE [01/1980-10/2009]) were used. Reference lists were checked for additional relevant studies. Observational studies (> or =50 participants) and randomized placebo-controlled intervention trials (RCTs) were considered.

RESULTS

25 studies met the inclusion criteria. Twenty-one observational cross-sectional studies (total number of participants n = 16185) showed inconsistent results. In one longitudinal observational study, low vitamin B12 concentrations were not associated with an increased risk of anaemia (total n = 423). The 3 RCTs (total n = 210) were well-designed and showed no effect of vitamin B12 supplementation on haemoglobin concentrations during follow-up in subjects with subnormal vitamin B12 concentrations at the start of the study. Due to large clinical and methodological heterogeneity, statistical pooling of data was not performed.

CONCLUSIONS

Evidence of a positive association between a subnormal serum vitamin B12 concentration and anaemia in older people is limited and inconclusive. Further well-designed studies are needed to determine whether subnormal vitamin B12 is a risk factor for anaemia in older people.