L. Hoey

Vitamin D deficiency is associated with inflammation in older Irish adults.

CONTEXTnInadequate vitamin D status is common within elderly populations and may be implicated in the etiology of autoimmune disease and inflammation. Few studies have investigated the relationship between vitamin D status and age-related immune dysfunction in humans.nnnOBJECTIVEnThe aim of this study was to investigate the association between vitamin D status and immune markers of inflammation in a large sample of older adults.nnnDESIGN, SETTING, AND PARTICIPANTSnAn observational investigation of 957 Irish adults (>60 years of age) recruited in Northern Ireland (55°N latitude) as part of the Trinity Ulster Department of Agriculture aging cohort study.nnnMAIN OUTCOME MEASUREnWe measured serum 25-hydroxyvitamin D (25(OH)D) by liquid chromatography tandem mass spectrometry and serum cytokines IL-6, TNF-α, IL-10, and C-reactive protein (CRP) by ELISA.nnnRESULTSnConcentrations of IL-6, CRP, and the ratios of IL-6 to IL-10 and CRP to IL-10 were significantly higher in individuals with deficient (<25 nmol/L) serum 25(OH)D compared with those with sufficient (>75 nmol/L) status after adjustment for age, sex, and body mass index (P < .05). Vitamin D status was a significant predictor of the IL-6 to IL-10 cytokine ratio, and those participants defined as deficient were significantly more likely to have an IL-6 to IL-10 ratio >2:1 compared with those defined as sufficient.nnnCONCLUSIONSnThis study demonstrated significant associations between low vitamin D status and markers of inflammation (including the ratio of IL-6 to IL-10) within elderly adults. These findings suggest that an adequate vitamin D status may be required for optimal immune function, particularly within the older adult population.

Dairy intakes in older Irish adults and effects on vitamin micronutrient status: Data from the TUDA study

BackgroundConsumption of dairy products has been associated with positive health outcomes including a lower risk of hypertension, improved bone health and a reduction in the risk of type 2 diabetes. The suggested dairy intake for health in older adults is three servings per day but recent analysis of the NHANES data for older adults reported 98% were not meeting these recommendations. No studies have investigated the consequences of such declines in the dairy intakes of Irish older adults and the subsequent effects on vitamin micronutrient status.ObjectivesTo study the daily dairy intakes of older Irish adults and to examine how the frequency of dairy food consumption affects vitamin micronutrient status.MethodsParticipants (n 4,317) were from the Trinity Ulster Department of Agriculture (TUDA) Study, a large study of older Irish adults (aged >60 yrs) designed to investigate gene-nutrient interactions in the development of chronic diseases of aging. The daily intake portion for milk, cheese and yoghurt was calculated from food frequency questionnaire (FFQ) responses. Blood samples were analysed for vitamin biomarkers as follows: vitamin B12 (total serum cobalamin and holotranscobalamin (holoTC)), folate (red cell folate (RCF) and serum folate), vitamin B2 (erythrocyte glutathione reductase activation coefficient (EGRac)), vitamin B6 (serum pyridoxal phosphate) and vitamin D (serum 25(OH)D).ResultsThe mean total reported dairy intake was 1.16 (SD 0.79) portions per day with males consuming significantly fewer total dairy portions compared to females (1.07 vs 1.21 respectively) (P<0.05). There was no significant difference in total daily dairy serving intakes by age decade (60-69, 70-79, >80 yrs). Overall, only 3.5% of the total population (n 151) achieved the recommended daily dairy intake of three or more servings per day. A significantly higher proportion of females (4%) compared to males (2.4%) met these dairy requirements (P=0.011). Blood concentrations of vitamin B12 biomarkers, RCF, vitamin B2 and vitamin B6 were significantly worse in those with the lowest tertile of dairy intake (0-0.71 servings) compared to those in the highest tertile (1.50-4.50 servings) (P<0.05).ConclusionThis study found that more than 96% of the older adults sampled did not meet current daily dairy intake recommendations. The study is the largest to-date examining dairy intakes in older Irish adults, and provides evidence that daily dairy intakes (in particular yogurt) contribute significantly to the B-vitamin and vitamin D biomarker status of older adults. These results suggest that older adults who are already vulnerable to micronutrient inadequacies, are forgoing the nutritional advantages of vitamin-rich dairy products.

An intervention trial to determine the response of vitamin B12 biomarkers to chronic supplementation with low dose vitamin B12 after folate repletion

Mandatory folic acid (FA) food fortification has been introduced in various countries, with the primary aim of preventing neural tube defects. It has been proposed that the inclusion of vitamin B12 together with FA may provide added health benefits and alleviate the problem of ‘masking’ of vitamin B12 deficiency by FA in the elderly. However, the response to supplementation with vitamin B12 at low doses has not been sufficiently investigated to date. The aim of the current study was to establish the minimum effective dose of vitamin B12 required to optimise B12 status and lower homocysteine. A 27-week, double-blinded, placebo controlled dose-response trial was conducted. Participants (n 231), healthy younger and older adults, initially took folic acid (400mg/day) for 11 weeks for repletion of folate status (the main determinant of homocysteine), and were then stratified according to homocysteine concentrations and randomised to receive one of the four treatments for 16 weeks: folic acid+ placebo; folic acid+ 3mg/day B12; folic acid + 10mg/day B12; folic acid + 50mg/day B12. An analysis of the B12 supplements at each dose was conducted in order to confirm their actual vitamin B12 content.

Low vitamin B12 and elevated folate status in older adults-a risk factor for cognitive impairment?

Studies post mandatory folic acid fortification in the US suggest that older adults with high folate but low vitamin B12 status have higher methylmalonic acid (MMA) and homocysteine (tHcy) concentrations as well as a higher risk of cognitive impairment compared to those with low B12 and normal folate status. However, studies from countries with voluntary but not mandatory folic acid fortification do not support these findings. Therefore, the aim of this study was to investigate folate and B12 status in relation to cognitive function in a large well-characterised older adult population exposed to a voluntary but liberal food fortification policy. Participants (n 5186) were from the Trinity Ulster Department of Agriculture (TUDA) Study, a large study of older Irish adults designed to investigate gene-nutrient interactions in the development of chronic diseases of ageing. Participants were recruited from General Practitioner practices in the Western and Northern Health and Social Care Trusts, Northern Ireland and those attending the memory and bone clinics in the Geriatric Unit of St. James Hospital, Dublin, Ireland. Blood samples were analysed for total serum cobalamin, holotranscobalamin, homocysteine (tHcy), red cell folate (RCF) folate and serum folate. Methylmalonic acid (MMA) determination was performed on a subset of samples (n 1477). Haematological and renal function data were accessed from the main study database. Cognitive function was assessed by repeatable battery for the assessment of neuropsychological status (RBANS) with a score ⩽80 indicating cognitive impairment. The population was divided into 4 categories based on serum B12 (<148 compared to ⩾148 pmol/L) and serum folate (< 60 and ⩾60 nmol/L) concentrations. Participants with either low B12 and low folate or low B12 and high folate status had significantly higher MMA and tHcy concentrations compared to the other groups (P< 0·05). Those with low B12 and high folate status (n 54) were significantly older, had a higher frequency of anaemia and cognitive impairment and had a higher use of folic acid supplements than all other groups (P< 0·05). These observational findings suggest that the classification criterion of low B12/high folate artificially selects the oldest old who are the frailest, most cognitively impaired and the most heavily supplemented with folic acid.

Is Vitamin B12 status a risk factor for falling in older adults (>60 yrs)?

. Currently, few studies have investigated markers of B12 status as a risk factor forfalling in large datasets from older adult populations. Therefore, the objective of this study was to assess markers of B12 status and risk offalling in a sample of Irish older adults ( n 4939) from the Trinity, Ulster, Department of Agriculture (TUDA) observational study.Participants were recruited between March 2009 and May 2012 and markers of vitamin B12 status included total serum B12 (micro-biological assay NCIB 12519, ATCC 43787) and Holo TC (Active B12) (Abbott AxSYM). Serum vitamin D was assessed by LCMS/MS(AB Sciex, USA) and fall related data were collected by health and lifestyle questionnaire.

Homocysteine and related B-vitamin status as determinants of bone mineral density in older Irish adults

Osteoporosis, a skeletal disorder characterised by compromised bone strength, results in an increased fracture risk (1) with considerable costs to both patients and the health service. While vitamin D has a well established role in bone health, evidence is emerging to support a role for the B-vitamins, and the related metabolite homocysteine (Hcy), in bone health (2,3) . The aim of this study was to investigate homocysteine and related B-vitamin status as determinants of bone mineral density (BMD). Existing data from a subset (n = 1276) of participants recruited to the Trinity Ulster Department of Agriculture (TUDA) study, a large observational cohort study of older Irish adults, were examined. Blood samples were analysed for plasma Hcy, red cell folate (RCF), serum folate and vitamin B12 at Trinity College Dublin. BMD at the total hip, femoral neck (FN) and spine were measured using dual energy X-ray absorptiometry (DXA) scans (Lunar Prodigy, GE Healthcare, UK). Of the general determinants of osteoporosis (defined as a T-Score of - 2.5 SD or lower), the following were found to be significant predictors: age ( b= 0.077, p < 0.001), female gender ( b= 1.153, p < 0.001) and BMI ( b= - 0.165, p < 0.001) (logistic regression). As expected, a higher incidence of osteoporosis was observed among women (25 %) compared with men (9 %). BMD values at the total hip and femoral neck were significantly higher in women with the highest red cell folate status compared to those with the lowest red cell folate status (Table).

Investigation of biomarker responses to depletion/repletion with vitamin B 12

Despite dietary intakes well above current recommendations, low biomarker status of vitamin B12 is a common problem in older adults, largely as a result of malabsorption of food-bound vitamin B12. This arises mainly from atrophic gastritis which leads to reduced gastric acid production (hypochlorhydria). Hydrochloric acid is essential for the absorption of food-bound vitamin B12, and thus vitamin B12 absorption is reduced in states of hypochlorhydria, although in theory free vitamin B12 (from supplements or fortified) should still be absorbed. Gastric acid suppressant medications, such as proton pump inhibitors (PPI) drugs induce hypochlorhydria and therefore a state similar to atrophic gastritis. The aim of the present study is to investigate the effect of hypochlorhydria on absorption of food-bound vitamin B12 and to determine whether low-dose supplemental vitamin B12 would overcome any vitamin B12 malabsorption. Forty-one healthy males, aged 18–45, participated in a vitamin B12 depletion/repletion trial. During the depletion phase (week 0–6) all subjects were administered with a PPI (omeprazole, 20mg/d); after which they were randomised (by vitamin B12 status as measured by serum holotranscobalamin; holoTC; the metabolically active fraction of total circulating vitamin B12) into one of the two treatment groups to receive; omeprazole (20mg/d) plus supplemental vitamin B12 (10 mg/d) or omeprazole (20mg/d) plus placebo for the repletion phase of the study (week 7–12).