Estimation of vitamin needs--riboflavin, vitamin B6 and ascorbic acid-according to blood parameters and functional-cognitive and emotional indices in a selected well-established group of elderly in a home for the aged in Israel

Vitamin C Status and Cognitive Function: A Systematic Review

Vitamin C plays a role in neuronal differentiation, maturation, myelin formation and modulation of the cholinergic, catecholinergic, and glutaminergic systems. This review evaluates the link between vitamin C status and cognitive performance, in both cognitively intact and impaired individuals. We searched the PUBMED, SCOPUS, SciSearch and the Cochrane Library from 1980 to January 2017, finding 50 studies, with randomised controlled trials (RCTs, n = 5), prospective (n = 24), cross-sectional (n = 17) and case-control (n = 4) studies. Of these, 36 studies were conducted in healthy participants and 14 on cognitively impaired individuals (including Alzheimer’s and dementia). Vitamin C status was measured using food frequency questionnaires or plasma vitamin C. Cognition was assessed using a variety of tests, mostly the Mini-Mental-State-Examination (MMSE). In summary, studies demonstrated higher mean vitamin C concentrations in the cognitively intact groups of participants compared to cognitively impaired groups. No correlation between vitamin C concentrations and MMSE cognitive function was apparent in the cognitively impaired individuals. The MMSE was not suitable to detect a variance in cognition in the healthy group. Analysis of the studies that used a variety of cognitive assessments in the cognitively intact was beyond the scope of this review; however, qualitative assessment revealed a potential association between plasma vitamin C concentrations and cognition. Due to a number of limitations in these studies, further research is needed, utilizing plasma vitamin C concentrations and sensitive cognitive assessments that are suitable for cognitively intact adults.

Characteristics of undernourished older medical patients and the identification of predictors for undernutrition status

Background

Undernutrition among older people is a continuing source of concern, particularly among acutely hospitalized patients. The purpose of the current study is to compare malnourished elderly patients with those at nutritional risk and identify factors contributing to the variability between the groups.

Methods

The study was carried out at the Soroka University Medical Center in the south of Israel. From September 2003 through December 2004, all patients 65 years-of-age or older admitted to any of the internal medicine departments, were screened within 72 hours of admission to determine nutritional status using the short version of the Mini Nutritional Assessment (MNA-SF). Patients at nutritional risk were entered the study and were divided into malnourished or 'at risk' based on the full version of the MNA. Data regarding medical, nutritional, functional, and emotional status were obtained by trained interviewers.

Results

Two hundred fifty-nine elderly patients, 43.6% men, participated in the study; 18.5% were identified as malnourished and 81.5% were at risk for malnutrition according to the MNA. The malnourished group was less educated, had a higher depression score and lower cognitive and physical functioning. Higher prevalence of chewing problems, nausea, and vomiting was detected among malnourished patients. There was no difference between the groups in health status indicators except for subjective health evaluation which was poorer among the malnourished group. Lower dietary score indicating lower intake of vegetables fruits and fluid, poor appetite and difficulties in eating distinguished between malnourished and at-risk populations with the highest sensitivity and specificity as compare with the anthropometric, global, and self-assessment of nutritional status parts of the MNA. In a multivariate analysis, lower cognitive function, education <12 years and chewing problems were all risk factors for malnutrition.

Conclusion

Our study indicates that low food consumption as well as poor appetite and chewing problems are associated with the development of malnutrition. Given the critical importance of nutritional status in the hospitalized elderly, further intervention trials are required to determine the best intervention strategies to overcome these problems.

Gender differences in factors associated with nutritional status of older medical patients

OBJECTIVES

To evaluate gender differences in nutritional risk of older people admitted to an acute-care general medical department, and identify gender-specific risk factors.

DESIGN

Cross-sectional study.

SETTING

Internal Medicine Department in an acute care, university-affiliated hospital in southern Israel.

SUBJECTS

204 cognitively intact patients aged 65 and over, admitted during a 12-month period to a general medical department.

MEASURES OF OUTCOME

Evaluation included demographic and clinical data consisting of the sum of medical conditions and of prescribed medications, evaluation of nutritional status, cognitive status, depression assessment and functional ability. Statistical analyses were conducted to evaluate the gender specific risk factors for under-nutrition.

RESULTS

32.5% of the men and 48.1% of the women admitted to an internal medicine department were at risk for under-nutrition. Those at nutritional risk had a higher rate of depression, lower cognitive and physical ability, poorer reported health status and more diagnosed diseases. Nutritional risk for men was associated with higher depression score, longer hospitalization, and poor appetite. For women, nutritional risk was associated with lower functional status and more diagnosed diseases. In a multivariate analysis, being a female increased the risk of under-nutrition by 3.3 fold.

CONCLUSION

Risk of under-nutrition is prevalent among older in-patients and is gender-related. Female inpatients are at markedly increased risk for under-nutrition. The mechanism of the gender discrepancy in factors related to nutritional deterioration is complex and poorly understood.

Effect of an enriched drink on cognitive function in frail elderly persons

BACKGROUND

Many elderly persons report that they have difficulties learning new things and remembering names, plans, and conversations. Because decreased cognitive function in elderly persons is potentially related to their poor nutritional status, provision of essential nutrients may improve cognitive function. The authors wanted to determine whether consumption of an enriched drink, including moderate doses of all essential micronutrients, improves cognitive function in frail elderly persons.

METHODS

Frail, white adults (n=101) who were aged 65 years or older with a body mass index<or=25 kg/m2 were selected for this randomized, double-blind, placebo-controlled trial. They received either an enriched drink or a placebo product for 6 months. Before and after the intervention, participants' cognitive function was assessed (word learning test [WLT], WLT delayed, category fluency [CF] for animals and professions, and recognition memory test for words [RMTW]) and blood biochemical analyses (vitamin B12, homocysteine) were performed.

RESULTS

Sixty-seven residents completed the study period. After 6 months, significant differences were noted in changes of the WLT (0.9+/-0.3 vs -0.1+/-0.3; p=.014) and CF professions (1.2+/-0.7 vs -0.6+/-0.5; p=.017) in the supplement group (n=34) compared with the placebo group (n=33). No significant differences were observed in WLT delayed, RMTW, and CF animals. The plasma vitamin B12 concentration increased (105+/-50 vs 8 +/-16; p=.003) and the homocysteine concentration decreased (-6.3+/-5.9 vs -0.3+/-2.9; p=.000) in the supplement group compared with the placebo group.

CONCLUSIONS

This study contributes to the evidence that nutritional supplementation may improve neuropsychological performance in frail elderly persons.

[The role of nutritional factors on the structure and function of the brain: an update on dietary requirements]

The brain is an organ elaborated and functioning from substances present in the diet. Dietary regulation of blood glucose level (via ingestion of food with a low glycemic index ensuring a low insulin level) improves the quality and duration of intellectual performance, if only because at rest the adult brain consumes 50 p. 100 of dietary carbohydrates, 80 p. 100 of them for energy purposes. The nature of the amino acid composition of dietary proteins contributes to good cerebral function; tryptophan plays a special role. Many indispensable amino acids present in dietary proteins help to elaborate neurotransmitters and neuromodulators. Omega-3 fatty acids provided the first coherent experimental demonstration of the effect of dietary nutrients on the structure and function of the brain. First it was shown that the differentiation and functioning of cultured brain cells requires omega-3 fatty acids. It was then demonstrated that alpha-linolenic acid (ALA) deficiency alters the course of brain development, perturbs the composition and physicochemical properties of brain cell membranes, neurones, oligodendrocytes, and astrocytes (ALA). This leads to physicochemical modifications, induces biochemical and physiological perturbations, and results in neurosensory and behavioral upset. Consequently, the nature of polyunsaturated fatty acids (in particular omega-3) present in formula milks for infants (premature and term) conditions the visual and cerebral abilities, including intellectual abilities. Moreover, dietary omega-3 fatty acids are certainly involved in the prevention of some aspects of cardiovascular disease (including at the level of cerebral vascularization), and in some neuropsychiatric disorders, particularly depression, as well as in dementia, notably Alzheimer's disease. Their deficiency can prevent the satisfactory renewal of membranes and thus accelerate cerebral aging. Iron is necessary to ensure oxygenation, to produce energy in the cerebral parenchyma, and for the synthesis of neurotransmitters. The iodine provided by the thyroid hormone ensures the energy metabolism of the cerebral cells. The absence of iodine during pregnancy induces severe cerebral dysfunction, leading to cretinism. Manganese, copper, and zinc participate in enzymatic mechanisms that protect against free radicals, toxic derivatives of oxygen. The use of glucose by nervous tissue implies the presence of vitamin B1. Vitamin B9 preserves memory during aging, and with vitamin B12 delays the onset of signs of dementia, provided it is administered in a precise clinical window, at the onset of the first symptoms. Vitamins B6 and B12, among others, are directly involved in the synthesis of neurotransmitters. Nerve endings contain the highest concentrations of vitamin C in the human body. Among various vitamin E components, only alpha-tocopherol is involved in nervous membranes. The objective of this update is to give an overview of the effects of dietary nutrients on the structure and certain functions of the brain.

Homocysteine effect on protein degradation rates

OBJECTIVES

To show the effect of homocysteine (Hcy) on the degradation rates of proteins.

DESIGN AND METHODS

Degradation rates of short-lived proteins in neutrophils were measured in in vivo human model of elevated plasma Hcy and lower vitamin status and in animal model of Hcy added in vitro to rat neutrophils.

RESULTS

In the human study, we found significant coefficients of correlation between plasma total homocysteine (tHcy) and the degradation rates of 21 protein fractions. In the animal model, Hcy significantly increased degradation rates of 57 protein fractions.

CONCLUSIONS

The increase in protein degradation rates, induced by Hcy, may provide a clue to our understanding of the mechanism of Hcy detrimental effects. Hcy may amplify the specific effect of cellular solutes on protein conformation, thereby monitor protein degradation rates to control enzyme activity. Consequently, the cell may lose its ability to maintain an efficient control of some crucial metabolic pathways, possibly leading to atherogenesis.

Plasma vitamin B-12 concentrations in an elderly latino population are predicted by serum gastrin concentrations and crystalline vitamin B-12 intake

The prevalence of vitamin B-12 deficiency increases with age, probably resulting from malabsorption of food-bound B-12 secondary to gastric atrophy. On the basis of this assumption, the Institute of Medicine (IOM) recommends those aged >50 y consume crystalline vitamin B-12. There is limited information on the prevalence of gastric atrophy in the elderly and whether the IOM recommendation would be effective. The objective of this study was to assess predictors of vitamin B-12 status and their interactions in free-living elderly. Individuals (n = 57) with deficient plasma vitamin B-12 (p-B12 < 148 pmol/L) were compared with 68 individuals with marginal p-B12 (148-221 pmol/L) and 52 with normal p-B12 (>221 pmol/L) in a cross-sectional sample (n = 1546) of elderly (>60 y) Latinos in California. Associations were examined among p-B12 and serum gastrin, vitamin B-12 intake from food and crystalline sources, and medications that putatively affect vitamin B-12 absorption. Serum gastrin was elevated, indicating gastric atrophy, in 48% of participants with deficient p-B12, 23% with marginal p-B12 and 21% of normal p-B12 participants, and was a significant predictor of deficient p-B12 and high plasma homocysteine (p-tHcy). Median total vitamin B-12 intake exceeded recommendations and was similar among status groups. Crystalline vitamin B-12 intake in the normal p-B12 group was higher than in the deficient p-B12 group (P < 0.01), and tended to be higher than the marginal group (P = 0.07). When serum gastrin was elevated, p-B12 was predicted by crystalline vitamin B-12, but not by intake of vitamin B-12 from food. Elevated serum gastrin was highly prevalent and predicted vitamin B-12 depletion. Crystalline vitamin B-12 intake predicted p-B12 in individuals with elevated serum gastrin, supporting IOM recommendations to increase consumption of crystalline vitamin B-12.

Dietary intake and eating patterns of elderly people in Israel: who is at nutritional risk?

OBJECTIVE

To determine dietary intake and eating patterns of older persons in Israel and to identify factors associated with low intake.

DESIGN

A cross-sectional study.

SETTING

Community-dwelling participants living in the Beer-Sheva area were interviewed at home, using a 24 h food questionnaire with additional questions regarding health and eating habits. Dietary intake was compared between people aged 65-74 and 75 y and older.

SUBJECTS

A total of 377 people over the age of 65 224 aged 65-74 and 153>75, were randomly selected from the Negev population.

RESULTS

Dietary intake of energy, fat, carbohydrates, vitamins E, C and B(1) were significantly lower for people aged 75 and older compared with people aged 65-74. Low energy intake was associated with lower subjective health status for men (P<0.01), poor appetite (P<0.01) and more gastrointestinal problems (P<0.05) for women and lower snack consumption (P<0.01) for both genders. In a multivariate model, low energy intake was associated with low appetite and higher use of medication for both sexes and with frequency of eating alone and not consuming snacks for men.

CONCLUSIONS

Dietary intake is lower among individuals older than 75 than in 65-74 y old. Risk factors for low intake include poor appetite and health status, gastrointestinal problems, and eating alone. Snacking enhanced dietary intake and should be encouraged in this group.

B vitamins, homocysteine, and neurocognitive function in the elderly

Evidence of the importance of the B vitamins folic acid, vitamin B-12, and vitamin B-6 for the well-being and normal function of the brain derives from data showing neurologic and psychologic dysfunction in vitamin deficiency states and in cases of congenital defects of one-carbon metabolism. The status of these vitamins is frequently inadequate in the elderly and recent studies have shown associations between loss of cognitive function or Alzheimer disease and inadequate B vitamin status. The question that arises is whether these B vitamin inadequacies contribute to such brain malfunctions or result from aging and disease. From a theoretical standpoint, these inadequacies could give rise to impairment of methylation reactions that are crucial to the health of brain tissue. In addition or perhaps instead, these inadequacies could result in hyperhomocysteinemia, a recently identified risk factor for occlusive vascular disease, stroke, and thrombosis, any of which may result in brain ischemia. Advances in the understanding of this putative relation between inadequate vitamin status and loss of cognitive function in the elderly are likely to be slow and may depend on the outcomes of both prospective studies and longitudinal studies in which nutritional intervention is provided before cognitive decline occurs.