Vitamin B12 deficiency in African American and white octogenarians and centenarians in Georgia

Metformin-induced vitamin B12 deficiency can cause or worsen distal symmetrical, autonomic and cardiac neuropathy in the patient with diabetes

Metformin blocks the absorption of vitamin B12 through a mechanism that has not been established but could be because of interference with the calcium-dependent binding of the intrinsic factor vitamin B12 complex to the cubam receptor in the terminal ileum. The subsequent deficiency of vitamin B12 may cause or accelerate distal symmetrical and autonomic neuropathy in the patient with diabetes. Several observational studies and meta-analyses have reported a significant association between metformin utilization and vitamin B12 deficiency. Prospective studies have shown that not only do metformin utilizers have lower vitamin B12 levels but they also have higher frequencies of distal symmetrical polyneuropathy and autonomic neuropathy (including cardiac denervation, which is associated with increased incidences of cardiac arrhythmias, cardiac events and mortality). Therefore, periodic monitoring of vitamin B12 is recommended in all patients who utilize metformin, particularly if metformin has been used for over 5 years at which stage hepatic stores of vitamin B12 would probably be depleted. Factors that accelerate the loss of hepatic vitamin B12 stores are proton pump inhibitors, bariatric surgery, being elderly and having an increased turnover of red blood cells. If serum vitamin B12 levels are borderline, measurement of methylmalonic acid and homocysteine levels can detect vitamin B12 deficiency at its earliest stage. Therapies include prophylactic calcium and vitamin B12 supplements, metformin withdrawal, replenishing vitamin B12 stores with intramuscular or oral vitamin B12 therapy and regular monitoring of vitamin B12 levels and vitamin B12 supplements if metformin continues to be utilized. With adequate vitamin B12 replacement, while symptoms of neuropathy may or may not improve, objective findings of neuropathy stabilize but do not improve.

Long-term metformin therapy and vitamin B12 deficiency: An association to bear in mind

To date, metformin remains the first-line oral glucose-lowering drug used for the treatment of type 2 diabetes thanks to its well-established long-term safety and efficacy profile. Indeed, metformin is the most widely used oral insulin-sensitizing agent, being prescribed to more than 100 million people worldwide, including patients with prediabetes, insulin resistance, and polycystic ovary syndrome. However, over the last decades several observational studies and meta-analyses have reported a significant association between long-term metformin therapy and an increased prevalence of vitamin B12 deficiency. Of note, evidence suggests that long-term and high-dose metformin therapy impairs vitamin B12 status. Vitamin B12 (also referred to as cobalamin) is a water-soluble vitamin that is mainly obtained from animal-sourced foods. At the cellular level, vitamin B12 acts as a cofactor for enzymes that play a critical role in DNA synthesis and neuroprotection. Thus, vitamin B12 deficiency can lead to a number of clinical consequences that include hematologic abnormalities (e.g., megaloblastic anemia and formation of hypersegmented neutrophils), progressive axonal demyelination and peripheral neuropathy. Nevertheless, no definite guidelines are currently available for vitamin B12 deficiency screening in patients on metformin therapy, and vitamin B12 deficiency remains frequently unrecognized in such individuals. Therefore, in this "field of vision" article we propose a list of criteria for a cost-effective vitamin B12 deficiency screening in metformin-treated patients, which could serve as a practical guide for identifying individuals at high risk for this condition. Moreover, we discuss additional relevant topics related to this field, including: (1) The lack of consensus about the exact definition of vitamin B12 deficiency; (2) The definition of reliable biomarkers of vitamin B12 status; (3) Causes of vitamin B12 deficiency other than metformin therapy that should be identified promptly in metformin-treated patients for a proper differential diagnosis; and (4) Potential pathophysiological mechanisms underlying metformin-induced vitamin B12 deficiency. Finally, we briefly review basic concepts related to vitamin B12 supplementation for the treatment of vitamin B12 deficiency, particularly when this condition is induced by metformin.

Ethnicity influences total serum vitamin B12 concentration: a study of Black, Asian and White patients in a primary care setting

AIMS

A growing body of evidence suggests that ethnicity and race influence vitamin B₁₂ metabolism and status yet clinical awareness of this is poor, causing doubts regarding diagnosis and treatment. Moreover, deficiency and insufficiency cut-offs are universally applied for this test in most diagnostic settings. The objective of this study was to assess serum vitamin B₁₂ concentrations in Black, Asian and White primary care patients in London, UK, particularly in patients of Black or Black British ethnic origin and establish if there is a need for specific reference ranges.

METHODS

Serum B₁₂ results from 49 414 patients were processed between January 2018 and November 2019 using the Architect assay (Abbott Diagnostics) at St. Thomas' Hospital, London, UK. Age, sex and ethnicity data were collected from the laboratory Health Informatics Team.

RESULTS

Black patients (n=13 806) were found to have significantly higher serum vitamin B₁₂ concentration across all age groups and both sexes, especially Nigerian patients (median B₁₂ 505 pmol/L,IQR: 362-727, n=891), compared with Asian and White ethnic groups (p<0.001). Binary logistic regression analysis revealed that the Black or Black British ethnic group had the strongest association with elevated serum B₁₂ (>652 pmol/L) (adjusted OR 3.38, 95% CI 3.17 to 3.61, p<0.0001).

CONCLUSIONS

It is likely that a combination of genetic and acquired/environmental factors are responsible for the ethnic differences in serum B₁₂. This suggests that there is a need for ethnic-specific reference ranges with indications for the incorporation of age and sex too.

High folic acid or folate combined with low vitamin B-12 status: potential but inconsistent association with cognitive function in a nationally representative cross-sectional sample of US older adults participating in the NHANES

BACKGROUND

Potential safety concerns relative to impaired cognitive function may exist when high folic acid exposures are combined with low vitamin B-12 status.

OBJECTIVES

We aimed to examine the relation of the coexistence of high folate and low vitamin B-12 status with cognitive function, utilizing various definitions of "high" folate status.

METHODS

Cross-sectional data from older adults (≥60 y; n = 2420) from the 2011-2014 NHANES were analyzed. High folate status was defined as unmetabolized serum folic acid (UMFA) > 1 nmol/L or serum total folate > 74.1 nmol/L, and low vitamin B-12 status as methylmalonic acid > 271 nmol/L or serum vitamin B-12 < 150 pmol/L. Logistic regression models estimated ORs of scoring low on 1 of 4 cognitive tests: the Digit Symbol Substitution Test (DSST), the Consortium to Establish a Registry for Alzheimer's Disease Delayed Recall (CERAD-DR) and Word Learning tests, and the Animal Fluency test (AF).

RESULTS

A significant interaction was observed relative to scoring low on the DSST (<34; UMFA; P-interaction = 0.0071) and AF (serum folate; P-interaction = 0.0078) for low vitamin B-12 and high folate status. Among those with low vitamin B-12, high UMFA or high serum total folate was associated with higher risk of scoring low on the DSST (OR: 2.16; 95% CI: 1.05, 4.47) and the AF (OR: 1.93; 95% CI: 1.08, 3.45). Among those with "normal" vitamin B-12, higher UMFA or serum total folate was protective on the CERAD-DR. In noninteraction models, when high folate and normal vitamin B-12 status was the reference group, low vitamin B-12 combined with high UMFA was associated with greater risk based on the DSST (<34, OR: 2.87; 95% CI: 1.85, 4.45; <40, OR: 2.22; 95% CI: 1.31, 3.75) and AF (OR: 1.97; 95% CI: 1.30, 2.97); but low vitamin B-12 and lower UMFA (OR: 1.69; 95% CI: 1.16, 2.47) was also significantly associated for DSST < 40 risk.

CONCLUSIONS

Low vitamin B-12 was associated with cognitive impairment both independently and in an interactive manner with high folate for certain cognitive performance tests among older adults.

Alcohol consumption and serum metabolite concentrations in young women

PURPOSE

Alcohol consumption is an established breast cancer risk factor, though further research is needed to advance our understanding of the mechanism underlying the association. We used global metabolomics profiling to identify serum metabolites and metabolic pathways that could potentially mediate the alcohol-breast cancer association.

METHODS

A cross-sectional analysis of reported alcohol consumption and serum metabolite concentrations was conducted among 211 healthy women 25-29 years old who participated in the Dietary Intervention Study in Children 2006 Follow-Up Study (DISC06). Alcohol-metabolite associations were evaluated using multivariable linear mixed-effects regression.

RESULTS

Alcohol was significantly (FDR p < 0.05) associated with several serum metabolites after adjustment for diet composition and other potential confounders. The amino acid sarcosine, the omega-3 fatty acid eicosapentaenoate, and the steroid 4-androsten-3beta,17beta-diol monosulfate were positively associated with alcohol intake, while the gamma-tocopherol metabolite gamma-carboxyethyl hydroxychroman (CEHC) was inversely associated. Positive associations of alcohol with 2-methylcitrate and 4-androsten-3beta,17beta-diol disulfate were borderline significant (FDR p < 0.10). Metabolite set enrichment analysis identified steroids and the glycine pathway as having more members associated with alcohol consumption than expected by chance.

CONCLUSIONS

Most of the metabolites associated with alcohol in the current analysis participate in pathways hypothesized to mediate the alcohol-breast cancer association including hormonal, one-carbon metabolism, and oxidative stress pathways, but they could also affect risk via alternative pathways. Independent replication of alcohol-metabolite associations and prospective evaluation of confirmed associations with breast cancer risk are needed.

Chronic Health Illnesses as Predictors of Mild Cognitive Impairment Among African American Older Adults

Approximately 5.5 million individuals are diagnosed with Alzheimer's disease (AD) dementia, a number which includes those with mild cognitive impairment and asymptomatic individuals with biomarkers of AD. There is a higher incidence of mild cognitive impairment (MCI) in African American populations as compared to White populations, even when controlling for sociodemographic factors. The existing body of ethnically/racially targeted research on MCI has been limited by few studies with the ability to generalize to African American communities. This study sought to examine whether medical conditions which occur at a higher rate in African American individuals increase the hazard of subsequent MCI development. A secondary data analysis of the National Alzheimer's Coordinating Center Uniform Data Set was employed to examine the associations between health conditions (congestive heart failure, traumatic brain injury, diabetes, hypertension, hypercholesterolemia, B12 deficiency, thyroid disease) and their relationship to MCI. The analytic sample included 2847 participants with 9872 observations. Binary logistic generalized estimating equation modeling was used to examine repeated measures over the course of 1-11 observations. Education was associated with MCI development, specifically those with some college or college graduates (p < 0.001) and more than college (p = 0.002). Female sex was associated with development of MCI (p < 0.001). African Americans with traumatic brain injury (TBI) were more likely to develop MCI (p < 0.001) compared to those with no reports of a TBI. Inactive thyroid conditions decreased the risk of MCI development (p = 0.005) compared to those without thyroid disease. Though vascular factors are often attributed to higher mortality and neurodegeneration in African Americans, congestive heart failure, diabetes, high cholesterol, hypertension, diabetes, nor seizures were associated with an increased risk of MCI development. Findings from this study provide formative data to develop targeted interventions for subsets of the African American community, including those with higher educational levels, those with TBI, and those with a history of thyroid disease. While it may not be possible to prevent MCI development, it is possible to modify lifestyle behaviors contributing to these health conditions, such as falls that are often experienced by older adults. Practitioners can increase awareness, knowledge, and resources relevant to clients.

Healthy ageing: the natural consequences of good nutrition-a conference report

Many countries are witnessing a marked increase in longevity and with this increased lifespan and the desire for healthy ageing, many, however, suffer from the opposite including mental and physical deterioration, lost productivity and quality of life, and increased medical costs. While adequate nutrition is fundamental for good health, it remains unclear what impact various dietary interventions may have on prolonging good quality of life. Studies which span age, geography and income all suggest that access to quality foods, host immunity and response to inflammation/infections, impaired senses (i.e., sight, taste, smell) or mobility are all factors which can limit intake or increase the body's need for specific micronutrients. New clinical studies of healthy ageing are needed and quantitative biomarkers are an essential component, particularly tools which can measure improvements in physiological integrity throughout life, thought to be a primary contributor to a long and productive life (a healthy "lifespan"). A framework for progress has recently been proposed in a WHO report which takes a broad, person-centered focus on healthy ageing, emphasizing the need to better understand an individual's intrinsic capacity, their functional abilities at various life stages, and the impact by mental, and physical health, and the environments they inhabit.

Association between MTHFR 677C>T Polymorphism and Vitamin B12 Deficiency: A Case-control Study

BACKGROUND

Vitamin B12 (cobalamin) deficiency is a prevalent worldwide health concern. Several factors are associated with vitamin B12 deficiency including lifestyle, genetic predisposition, and malfunctions in the absorption and transport of vitamin B12. In the current case-control study, we aimed at investigating the association between MTHFR polymorphisms and vitamin B12 deficiency in a Jordanian population.

METHODS

Two polymorphic sites of the MTHFR gene (c.677C>T, rs1801133 and c.1286A>C, rs1801131) were analyzed using RFLP and DNA sequencing in a group of vitamin B12 deficient individuals (45 males and 55 females). As a control, 100 matching individuals (age and sex) with vitamin B12 levels > 200 ng/mL were also recruited for this study.

RESULTS

The MTHFR c.677C>T variant was significantly associated with vitamin B12 deficiency in individuals from northern Jordan. The frequency of the homozygous MTHFR c.677C>T genotype was significantly higher in B12 deficient individuals in comparison with the control group (X2 = 8.397, p = 0.0150). The T allele frequency showed significant association with vitamin B12 deficiency in the study population (OR= 1.684, 95% CI: 1.116 to 2.542, p = 0.017). On the other hand, the MTHFR c.1286A>C variant did not show significant association with vitamin B12 deficiency in the selected population.

CONCLUSIONS

Our results showed a significant association between homozygous MTHFR c.677C>T variant and T allele frequencies and vitamin B12 deficiency in the Jordanian population.

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.

Vitamin B12 deficiency

Vitamin B₁₂ (B12; also known as cobalamin) is a B vitamin that has an important role in cellular metabolism, especially in DNA synthesis, methylation and mitochondrial metabolism. Clinical B12 deficiency with classic haematological and neurological manifestations is relatively uncommon. However, subclinical deficiency affects between 2.5% and 26% of the general population depending on the definition used, although the clinical relevance is unclear. B12 deficiency can affect individuals at all ages, but most particularly elderly individuals. Infants, children, adolescents and women of reproductive age are also at high risk of deficiency in populations where dietary intake of B12-containing animal-derived foods is restricted. Deficiency is caused by either inadequate intake, inadequate bioavailability or malabsorption. Disruption of B12 transport in the blood, or impaired cellular uptake or metabolism causes an intracellular deficiency. Diagnostic biomarkers for B12 status include decreased levels of circulating total B12 and transcobalamin-bound B12, and abnormally increased levels of homocysteine and methylmalonic acid. However, the exact cut-offs to classify clinical and subclinical deficiency remain debated. Management depends on B12 supplementation, either via high-dose oral routes or via parenteral administration. This Primer describes the current knowledge surrounding B12 deficiency, and highlights improvements in diagnostic methods as well as shifting concepts about the prevalence, causes and manifestations of B12 deficiency.

B-vitamin status and bone mineral density and risk of lumbar osteoporosis in older females in the United States

BACKGROUND

Previous data suggest that elevated serum total homocysteine (tHcy) may be a risk factor for bone fracture and osteoporosis. Nutritional causes of elevated tHcy are suboptimal B-vitamin status. To our knowledge, this is the first nationally representative report on the relation of B vitamins and bone health from a population with folic acid fortification.

OBJECTIVE

The purpose of this analysis was to examine the relation between B-vitamin status biomarkers and bone mineral density (BMD), risk of osteoporosis, and biomarkers of bone turnover.

DESIGN

We examined the relation of tHcy, methylmalonic acid (MMA), and serum/red blood cell folate and total-body and lumbar spine BMD in women aged ≥50 y participating in the NHANES 1999-2004 (n = 2806), a nationally representative cross-sectional survey. These are the only years with concurrent measurement of tHcy and whole-body dual-energy X-ray absorptiometry. We also examined B-vitamin biomarkers relative to bone turnover markers, bone alkaline phosphatase, and urinary N-terminal cross-linked telopeptide of type I collagen in a 1999-2002 subset with available data (n = 1813).

RESULTS

In comparison with optimal concentrations, women with elevated tHcy were older with lower serum vitamin B-12, red blood cell folate, and dietary micronutrient intakes and had significantly higher mean ± SE markers of bone turnover (bone alkaline phosphatase: 15.8 ± 0.59 compared with 14.0 ± 0.25 μg/L; urinary N-terminal cross-linked telopeptide of type I collagen: 48.2 ± 2.9 compared with 38.9 ± 0.90 nmol bone collagen equivalents per mmol creatinine/L). Elevated MMA (OR: 1.88; 95% CI: 1.10, 3.18) and tHcy (OR: 2.17; 95% CI: 1.14, 4.15) were related to increased risk of lumbar osteoporosis. When examined as a continuous variable, tHcy was negatively associated, serum folates were positively associated, and MMA and vitamin B-12 were not significantly associated with lumbar and total-body BMD.

CONCLUSION

In this nationally representative population of older US women with high exposure to B vitamins through food fortification and dietary supplements, only elevated tHcy and MMA were independently associated with risk of lumbar spine osteoporosis.

Vitamin K and other markers of micronutrient status in morbidly obese patients before bariatric surgery

BACKGROUND

Micronutrient deficiencies occur in morbidly obese patients. The aim of this study was to assess vitamin deficiencies prior to bariatric surgery including vitamin K about which there is little data in this population.

METHODS

A prospective assessment of 118 consecutive patients was performed. Clinical allied with haematological and biochemical variables were measured. Micronutrients measured included vitamins K1 , PIVKA-II (protein-induced in vitamin K absence factor II), vitamin D, vitamin B12 (holotranscobalamin), iron, transferrin and folate.

RESULTS

Patients were aged 49 ± 11 [mean (SD, standard deviation)] years, body mass index (BMI) 50 ± 8 kg/m(2), 66% female and 78% Caucasian. Hypertension was present in 47% and type 2 diabetes in 32%. Vitamin D supplements had been prescribed in 8%. Micronutrient insufficiencies were found for vitamin K (40%), vitamin D (92%) and vitamin B12 (25%), and also iron (44%) and folate (18%). Normocalcaemic vitamin D insufficiency with secondary hyperparathyroidism was present in 18%. Iron and transferrin levels were associated with age, sex and estimated glomerular filtration rate. Vitamin K levels were associated with age, and inversely with BMI and diabetes mellitus; and PIVKA-II with smoking, triglycerides and liver function markers. Vitamin D levels were associated with statin use and prescription of supplements and inversely with BMI. Vitamin B12 levels were associated with ethnicity and HbA1c.

CONCLUSION

Micronutrient status shows differing relationships with age, gender and BMI. Vitamin K insufficiency was present in 40% and not related to deficiencies in other vitamins or micronutrients. Vitamin D and vitamin K supplementation should be considered prebariatric surgery in patients with diabetes or severe insulin resistance.

Vitamin B12 levels of subjects aged 0-24 year(s) in Konya, Turkey

Research reports indicate that vitamin B12 levels show racial differences, which suggests that using the reference ranges of varied populations may lead to inaccurate results. This study aimed to determine normal serum levels of vitamin B12 among children and young people in the Konya region of Turkey. It evaluated 1,109 samples; 54 were from cord-blood and 1,055 were from healthy subjects aged 0-24 year(s), who were admitted to primary healthcare centres. The normal reference levels obtained for vitamin B12 at 2.5-97.5 percentile (P2.5-P97.5) range were 127-606 pg/mL for girls, 127-576 pg/mL for boys, and 127-590 pg/mL for the entire study group. The reported reference values for vitamin B12 in other studies were higher than the current results. Vitamin B12 levels vary from country to country; comparisons between countries may not be valid, and normal levels for each population should be obtained.

Vitamin B12 deficiency in relation to functional disabilities

This study was designed to assess whether symptoms, functional measures, and reported disabilities were associated with vitamin B12 (B12) deficiency when defined in three ways. Participants, aged 60 or more years of age, in 1999–2002 National Health and Nutrition Examination Surveys (NHANES) were categorized in relation to three previously used definitions of B12 deficiency: (1) serum B12 < 148 pmol/L; (2) serum B12 < 200 pmol/L and serum homocysteine > 20 μmol/L; and (3) serum B12 < 258 pmol/L or serum methylmalonic acid > 0.21 μmol/L. Functional measures of peripheral neuropathy, balance, cognitive function, gait speed, along with self-reported disability (including activities of daily living) were examined with standardized instruments by trained NHANES interviewers and technicians. Individuals identified as B12 deficient by definition 2 were more likely to manifest peripheral neuropathy OR (odds) (95% confidence intervals), p value: 9.70 (2.24, 42.07), 0.004 and report greater total disability, 19.61 (6.22, 61.86) 0.0001 after adjustments for age, sex, race, serum creatinine, and ferritin concentrations, smoking, diabetes, and peripheral artery disease. Smaller, but significantly increased, odds of peripheral neuropathy and total disability were also observed when definition 3 was applied. Functional measures and reported disabilities were associated with B12 deficiency definitions that include B12 biomarkers (homocysteine or methylmalonic acid). Further study of these definitions is needed to alert clinicians of possible subclinical B12 deficiency because functional decline amongst older adults may be correctable if the individual is B12 replete.

Profiles of cognitive functioning in a population-based sample of centenarians using factor mixture analysis

BACKGROUND/STUDY CONTEXT: The goal of the study was to identify and characterize latent profiles (clusters) of cognitive functioning in centenarians and the psychometric properties of cognitive measures within them.

METHODS

Data were collected from cross-sectional, population-based sample of 244 centenarians (aged 98 to 108, 15.8% men, 20.5% African American, 38.0% community-dwelling) from 44 counties in northern Georgia participating in the Georgia Centenarian Study (2001-2008). Measures included the Mini-Mental State Examination (MMSE), Severe Impairment Battery (SIB), Wechsler Adult Intelligence Scale-III Similarities subtest (WAIS), Hand Tapping, Behavioral Dyscontrol Scale (BDS), Controlled Oral Word Association Test (COWAT), and Fuld Object Memory Evaluation (FOME). The Global Deterioration Rating Scale (GDRS) was used to independently evaluate criterion-related validity for distinguishing cognitively normal and impaired groups. Relevant covariates included directly assessed functional status for basic and instrumental activities of daily living (DAFS), race, gender, educational attainment, Geriatric Depression Scale Short Form (GDS), and vision and hearing problems.

RESULTS

Results suggest two distinct classes of cognitive performance in this centenarian sample. Approximately one third of the centenarians show a pattern of markedly lower cognitive performance on most measures. Group membership is independently well predicted (area under the curve [AUC] = .83) by GDRS scores (sensitivity 67.7%, specificity 82.4%). Membership in the lower cognitive performance group was more likely for individuals who were older, African Americans, had more depressive symptoms, lower plasma folate, carriers of the apolipoprotein E (APOE) ε4 allele, facility residents, and individuals who died in the 2 years following interview.

CONCLUSIONS

In a population expected to have high prevalence of dementia, latent subtypes can be distinguished via factor mixture analysis that provide normative values for cognitive functioning. The present study allows estimates for normative cognitive performance in this age group.

Strategies to improve diet in older adults

It is estimated that by 2050 there will be 2 billion people aged 60 years and older in the world. The evidence base for the health benefits of good nutrition and physical activity, as well as weight loss among overweight and obese adults, is growing and a number of policies and guidelines are available to guide health professionals in serving older people at various stages of the lifecycle. There are many potential influences on dietary habits including individual factors, families and friends, community characteristics, the food and supplement industry, and public policy. This review focuses on the evidence base for factors influencing diet in older adults, food insecurity, Na, vitamin D, vitamin B12, protein, obesity and the benefits of energy restriction in overweight and obese older adults. Research is needed to continue to increase the evidence base for appropriate ways to improve diet and health in older people. Also, much of the available information is from the US, so there is a need to conduct research in other areas of the world.

Race/ethnicity-, gender- and age-specific differences in micronutrient intakes of US adults with and without diabetes

Race/ethnicity-, gender- and age-specific differences in dietary micronutrient intakes of US adults ≥  21 years were assessed from National Health and Nutrition Examination Survey, 2007-2008. The participants included Black non-Hispanics, Mexican-American and White non-Hispanics who signed an informed consent form for the interview and who completed the in-person 24-h recall. Micronutrient intakes were based on the Institute of Medicines' classifications of recommended dietary allowances specific for age and gender. Likelihood of many micronutrient insufficiencies was associated with being female, over 65 years, having diabetes and minority status. Younger and female adults had a greater likelihood of iron insufficiency than male and older adults. These findings demonstrate the importance of considering the intersection of age, gender and race in setting policies for micronutrient deficiency screening, particularly in young female adults and minorities.

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.

The oldest old: red blood cell and plasma folate in African American and white octogenarians and centenarians in Georgia

OBJECTIVE

To determine the overall folate status of a population-based multi-ethnic sample of octogenarians and centenarians and the specific dietary, demographic and physiological factors associated with observed abnormalities.

DESIGN

Population-based multiethnic sample of adults aged 80 to 89 and 98 and above.

SETTING

Northern Georgia, USA.

PARTICIPANTS

Men and women aged 80 to 89 (octogenarians, n = 77) and 98 and older (centenarians, n = 199).

ANALYSES

Wilcoxon rank sum tests, and Chi square and logistic regression analyses were used to examine associations of low and high folate status with hematological indicators and other variables of interest.

RESULTS

The prevalence of low red blood cell (RBC) folate was low overall, but tended to be higher in centenarians than in octogenarians (6.5% vs. 1.3%, p = 0.058; defined as RBC folate < 317 nmol/L). The risk of having lower RBC folate (< 25th vs. > 25th percentile for RBC folate for 60yr+ in NHANES 1999-2000) was greater in association with vitamin B12 deficiency (OR = 5.36; 95%CI: 2.87-10.01), African American race (OR = 4.29; 95%CI: 2.08-8.83), and residence in a skilled nursing facility (OR = 3.25; 95%CI: 1.56-6.78) but was not influenced by age, gender, B-vitamin supplement use, high/low food score or presence of atrophic gastritis. Combined high plasma folate and low vitamin B12 status was present in some individuals (n=11), but was not associated with increased prevalence of anemia or cognitive impairment in this study.

CONCLUSIONS

Low RBC folate status (< 317 nmol/L) was rare in this post folic acid fortification sample of octogenarians and centenarians. RBC folate status (< 25th percentile) was strongly associated with 1) vitamin B12 deficiency, which has strong implications for vitamin treatment, and 2) with being African American, suggesting racial disparities exist even in the oldest old.

Monitoring of vitamin B-12 nutritional status in the United States by using plasma methylmalonic acid and serum vitamin B-12

BACKGROUND

Various definitions, criteria, tests, and cutoffs have been used to define vitamin B-12 status; however, a need exists for the systematic study of vitamin B-12 status in the United States because of concerns about high folic acid intakes and the potential for associated adverse effects.

OBJECTIVE

The objective was to determine the effect of different cutoff choices on outcomes and of the different degrees of serum vitamin B-12 status, definable by the concurrent use of a functional and circulating marker as the first steps to developing a data-based consensus on the biochemical diagnosis of vitamin B-12 deficiency.

DESIGN

Data from NHANES, a nationally representative cross-sectional survey, were examined for adults aged >19 y (mean ± SD age: 45 ± 1 y) from 1999 to 2004 (n = 12,612).

RESULTS

Commonly used cutoffs had a greater effect on prevalence estimates of low vitamin B-12 status with the use of vitamin B-12 than with the use of methylmalonic acid (MMA; 3-26% and 2-6%, respectively). A cutoff of >148 pmol/L for vitamin B-12 and of ≤210 nmol/L for MMA resulted in significant misclassifications. Approximately 1% of adults had a clear vitamin B-12 deficiency (low vitamin B-12 and elevated MMA); 92% of adults had adequate vitamin B-12 status. A high percentage of younger women characterized the group with low vitamin B-12 and normal MMA (2% of adults) and may have falsely reflected low vitamin B-12. Adults with elevated MMA (5%) only were demographically similar (ie, by age and race) to the deficient group and may have included some individuals with early vitamin B-12 deficiency.

CONCLUSIONS

These analyses indicate the challenges of assessing vitamin B-12 status when uncertainties exist about the appropriate cutoffs. Future studies should determine definable endpoints to achieve this goal.

Biomarkers of cobalamin (vitamin B-12) status in the epidemiologic setting: a critical overview of context, applications, and performance characteristics of cobalamin, methylmalonic acid, and holotranscobalamin II

Cobalamin deficiency is relatively common, but the great majority of cases in epidemiologic surveys have subclinical cobalamin deficiency (SCCD), not classical clinical deficiency. Because SCCD has no known clinical expression, its diagnosis depends solely on biochemical biomarkers, whose optimal application becomes crucial yet remains unsettled. This review critically examines the current diagnostic concepts, tools, and interpretations. Their exploration begins with understanding that SCCD differs from clinical deficiency not just in degree of deficiency but in fundamental pathophysiology, causes, likelihood and rate of progression, and known health risks (the causation of which by SCCD awaits proof by randomized clinical trials). Conclusions from SCCD data, therefore, often may not apply to clinical deficiency and vice versa. Although many investigators view cobalamin testing as unreliable, cobalamin, like all diagnostic biomarkers, performs satisfactorily in clinical deficiency but less well in SCCD. The lack of a diagnostic gold standard limits the ability to weigh the performance characteristics of metabolic biomarkers such as methylmalonic acid (MMA) and holotranscobalamin II, whose specificities remain incompletely defined outside their relations to each other. Variable cutoff selections affect diagnostic conclusions heavily and need to be much better rationalized. The maximization of reliability and specificity of diagnosis is far more important today than the identification of ever-earlier stages of SCCD. The limitations of all current biomarkers make the combination of ≥2 test result abnormalities, such as cobalamin and MMA, the most reliable approach to diagnosing deficiency in the research setting; reliance on one test alone courts frequent misdiagnosis. Much work remains to be done.

Body mass index is associated with dietary patterns and health conditions in georgia centenarians

Associations between body mass index (BMI) and dietary patterns and health conditions were explored in a population-based multiethnic sample of centenarians from northern Georgia. BMI ≤20 and ≥25 was prevalent in 30.9% and 25.3% of study participants, respectively. In a series of logistic regression analyses controlled for gender and place of residence, the probability of having BMI ≥25 was increased by being black versus white and having a low citrus fruit, noncitrus fruit, orange/yellow vegetable or total fruit and vegetable intake. The probability of having BMI ≤20 was not associated with dietary intake. When controlled for race, gender, residence, and total fruit and vegetable intake, BMI ≥25 was an independent risk factor for diabetes or having a systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg, whereas BMI ≤20 was a risk factor for anemia. Given the many potential adverse consequences of under- and overweight, efforts are needed to maintain a healthy weight, even in the oldest old.

Discovery of novel sources of vitamin b(12) in traditional korean foods from nutritional surveys of centenarians

Human longevity can be explained by a variety of factors, among them, nutritional factor would play an important role. In our study of Korean centenarians for their longevity, the apparent nutritional imbalance in the traditional semi-vegetarian diet raised a special attention, especially on vitamin B₁₂ status, supplied by animal foods. Interestingly, we found that the prevalence of vitamin B₁₂ deficient Korean centenarians was not higher compared with those from Western nations with animal-oriented traditional foods. We assumed that there might be some unveiled sources for vitamin B₁₂ in the Korean traditional foods. Screening of vitamin B₁₂ contents has revealed that some traditional soybean-fermented foods, such as Doenjang and Chunggukjang, and seaweeds contain considerable amounts of vitamin B₁₂. Taken together, it can be summarized that the traditional foods, especially of fermentation, might be evaluated for compensation of the nutritional imbalance in the vegetable-oriented dietary pattern by supplying vitamin B₁₂, resulting in maintenance of health status.

Nutrition in centenarians

The oldest old are among the fastest growing segment of the population and it is important to understand not only the influence of modifiable lifestyle factors such as diet and nutrition on the achievement of exceptional longevity but also the role, if any, of these factors on maintaining optimal cognitive, mental and physical health into advanced age. This review summarizes studies of dietary intake and patterns of long-lived peoples and presents current knowledge of nutritional status of centenarians as determined with nutritionally relevant biomarkers, providing information on comparative levels of the various biomarkers between centenarians and older adult controls and on the prevalence and predictors of nutritional deficiencies in centenarians. The studies indicate that BMI and nutritional status as indicated by circulating levels of antioxidant vitamins, vitamin B12, folate, homocysteine and 25(OH) vitamin D of centenarians are quite heterogeneous and influenced by region of residency and many of the demographic, dietary and lifestyle factors that influence nutritional status in other older adults. While many of the studies have been small, convenience samples of relatively healthy community-dwelling centenarians, a few have population-based or included participants of varying cognitive functioning. These and future studies examining associations between nutritional status and cognitive, mental and physical function should be instrumental in determining the role of nutrition in promoting longevity and improving the quality of life in these exceptional survivors.

Cognitive function, physical performance, health, and disease: norms from the georgia centenarian study

This study provides, for the first time, normative data on cognitive functioning and physical performance, health and health behaviors, and diseases from a population-based sample of 244 centenarians and near-centenarians (M age = 100.5 years, range 98-108, 84.8% women, 21.3% African American) from the Georgia Centenarian Study. Data are presented by the four key dimensions of gender, race, residence, and educational attainment. Results illustrate the profound range of functioning in this age group and indicate considerable differences as a function of each dimension. Bivariate models generally suggest that cognitive functioning and physical performance is higher for men than women; whites than African Americans; community than facility residents; and those with more than high school education than those with less than high school education. Multivariate models elaborate that differences in educational attainment generally account for the largest proportion of variance in cognitive functioning and residential status generally accounts for the largest proportion of variance in physical performance measures. Addition of health variables seldom increases variance accounted for in each domain beyond these four dimensions.