Water homeostasis, frailty and cognitive function in the nursing home

OBJECTIVE

- To develop and test a practical clinical method to assess frailty in nursing homes; - To investigate the relationship between cognitive status of the elderly and the balance between water compartments of their body composition.

DESIGN AND SUBJECTS

Cross-sectional study, conducted at two nursing homes in Boston-MA.

METHODS

Body mass and height (Ht) were evaluated to calculate BMI (body mass index, in Kg/m²). The cognitive decline was evaluated based on the scores obtained from the Mini-Mental State Examination (MMSE); The extracellular to total body water ratio (ECW/TBW) was calculated after the analysis of TBW from deuterium and tritium dilution and ECW from bromide dilution. Single-frequency BIA analysis data were investigated for resistance (R) and reactance (Xc), plotted in an R/Ht Xc/Ht graph (vectorial analysis-BIVA). The BIVA results of nursing home residents were compared against the data obtained from the NHANES III study. TBW and ECW values were compared with a group of free-living elderly volunteers.

RESULTS

The ECW/TBW was significantly higher in nursing home residents than in the free-living individuals. BIVA analysis showed significantly higher Xc/Ht values in the reference subjects. The MMSE did not present a significant correlation with ECW/TBW for either gender.

CONCLUSION

We proposed the ECW/TBW ratio and BIVA as surrogate methods for the clinical assessment of frailty. We tested successfully both approaches with nursing home patients and free-living volunteers and compared them to a national data base. The advent of new, portable instruments will enable field tests to further validate our proposed "Frailty Factor" in future studies. We found no correlation between frailty and cognitive decline in the nursing home.

Multivitamin/mineral supplementation improves plasma B-vitamin status and homocysteine concentration in healthy older adults consuming a folate-fortified diet

Elevated homocysteine has been identified as an independent risk factor for cardiovascular and cerebrovascular disease. Although multivitamin use has been associated with low plasma homocysteine concentrations in several observational studies, no clinical trials have been conducted using multivitamin/mineral supplements to lower homocysteine. We determined whether a multivitamin/mineral supplement formulated at about 100% Daily Value will further lower homocysteine concentration and improve B-vitamin status in healthy older adults already consuming a diet fortified with folic acid. In this randomized, double-blind, placebo-controlled trial, 80 free-living men and women aged 50-87 y with total plasma homocysteine concentrations of > or =8 micromol/L received either a multivitamin/mineral supplement or placebo for 56 d while consuming their usual diet. After the 8-wk treatment, subjects taking the supplement had significantly higher B-vitamin status and lower homocysteine concentration than controls (P: < 0.01). Plasma folate, pyridoxal phosphate (PLP) and vitamin B-12 concentrations were increased 41.6, 36.5 and 13.8%, respectively, in the supplemented group, whereas no changes were observed in the placebo group. The mean homocysteine concentration decreased 9.6% in the supplemented group (P: < 0.001) and was unaffected in the placebo group. There were no significant changes in dietary intake during the intervention. Multivitamin/mineral supplementation can improve B-vitamin status and reduce plasma homocysteine concentration in older adults already consuming a folate-fortified diet.

The effects of a multivitamin/mineral supplement on micronutrient status, antioxidant capacity and cytokine production in healthy older adults consuming a fortified diet

BACKGROUND

Inadequate micronutrient intake among older adults is common despite the increased prevalence of fortified/enriched foods in the American diet. Although many older adults take multivitamin supplements in an effort to compensate, studies examining the benefits of this behavior are absent.

OBJECTIVE

To determine whether a daily multivitamin/mineral supplement can improve micronutrient status, plasma antioxidant capacity and cytokine production in healthy, free-living older adults already consuming a fortified diet.

METHODS

An eight-week double-blind, placebo-controlled clinical trial among 80 adults aged 50 to 87 years (mean = 66.5 +/- 8.6 years).

RESULTS

Multivitamin treatment significantly increased (p<0.01, compared to placebo) plasma concentrations of vitamins D (77 to 100 nmol/L), E (27 to 32 micromol/L), pyridoxal phosphate (55.1 to 75.2 nmol/L), folate (23 to 33 nmol/L), B12 (286 to 326 pmol/L)), C (55 to 71 micromol/L), and improved the riboflavin activity coefficient (1.23 to 1.15), but not vitamins A and thiamin. The multivitamin reduced the prevalence of suboptimal plasma levels of vitamins E (p=0.003), B12 (p=0.004), and C (p=0.08). Neither glutathione peroxidase activity nor antioxidant capacity (ORAC) were affected. No changes were observed in interleukin-2, -6 or -10 and prostaglandin E2, proxy measures of immune responses.

CONCLUSIONS

Supplementation with a multivitamin formulated at about 100% Daily Value can decrease the prevalence of suboptimal vitamin status in older adults and improve their micronutrient status to levels associated with reduced risk for several chronic diseases.

Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring study

BACKGROUND

Low vitamin B-12 status is prevalent among the elderly, but few studies have examined the association between vitamin B-12 status and intake.

OBJECTIVE

We hypothesized that vitamin B-12 concentrations vary according to intake source.

DESIGN

Plasma concentrations and dietary intakes were assessed cross-sectionally for 2999 subjects in the Framingham Offspring Study. The prevalence of vitamin B-12 concentrations <148, 185, and 258 pmol/L was examined by age group (26-49, 50-64, and 65-83 y), supplement use, and the following food intake sources: fortified breakfast cereal, dairy products, and meat.

RESULTS

Thirty-nine percent of subjects had plasma vitamin B-12 concentrations <258 pmol/L, 17% had concentrations <185 pmol/L, and 9% had concentrations <148 pmol/L, with little difference between age groups. Supplement users were significantly less likely than non-supplement-users to have concentrations <185 pmol/L (8% compared with 20%, respectively). Among non-supplement-users, there were significant differences between those who consumed fortified cereal >4 times/wk (12%) and those who consumed no fortified cereal (23%) and between those in the highest and those in the lowest tertile of dairy intake (13% compared with 24%, respectively), but no significant differences by meat tertile. Regression of plasma vitamin B-12 on log of intake, by source, yielded significant slopes for each contributor adjusted for the others. For the total group, b = 40.6 for vitamin B-12 from vitamin supplements. Among non-supplement-users, b = 56.4 for dairy products, 35.2 for cereal, and 16.7 for meat. Only the meat slope differed significantly from the others.

CONCLUSIONS

In contrast with previous reports, plasma vitamin B-12 concentrations were associated with vitamin B-12 intake. Use of supplements, fortified cereal, and milk appears to protect against lower concentrations. Further research is needed to investigate possible differences in bioavailability.

Decreasing ascorbate intake does not affect the levels of glutathione, tocopherol or retinol in the ascorbate-requiring osteogenic disorder shionogi rats

Levels of glutathione in liver and kidney, and other nutrients in plasma were evaluated in male and female ascorbate-requiring osteogenic disorder Shionogi (ODS) rats fed semipurified diets in which the concentrations of ascorbate were gradually decreased from 1965 to 180 mg/kg. Plasma ascorbate levels in ODS rats were unaffected when ascorbate levels in the diet were decreased from 1965 to 768 mg/kg. However, plasma ascorbate levels decreased progressively when levels of ascorbate in the diet were decreased from 527 to 180 mg/kg. Plasma ascorbate levels decreased up to 77% when the dietary ascorbate concentration decreased from 1965 to 180 mg/kg. Ascorbate levels in liver and kidney fell as much as 60-70% when the dietary ascorbate levels were reduced from 1965 to 180 mg/kg. However, the glutathione levels in these tissues were not affected. Plasma retinol and vitamin E levels were not affected by decreasing dietary ascorbate intake. Total cholesterol levels increased significantly in female rats as dietary ascorbate intake declined. Levels of glycated hemoglobin decreased significantly when dietary ascorbate levels decreased from 1965 to 527 mg/kg. This study suggests that levels of vitamin E, retinol and glutathione are not affected by decreased dietary intake of ascorbate under nonscorbutic conditions, whereas elevated ascorbate intake is associated with a decrease in levels of plasma cholesterol in female ODS rats. However, excessive intake of ascorbate may be associated with elevated glycation of hemoglobin. To achieve the maximal health benefit of ascorbate supplementation, further studies are necessary to define optimal ascorbate intakes.

The effects of aging and calorie restriction on plasma nutrient levels in male and female Emory mice

We examined the effect of diet, age (4.5, 13 and 23 months), and sex on plasma levels of retinol, tocopherol, ascorbate, cholesterol, glucose and glycohemoglobin in male and female Emory mice which were fed control (C) and 50% calorie restricted (R) diets. Results showed that C fed animals tended to have higher levels of plasma ascorbate (50-71%), cholesterol (23-71%), glucose (38-81%) and glycohemoglobin (50%). However, these diet differences varied with the age and sex of the animals. Plasma retinol levels were lower only in R males vs. C males (50%). Novel sex-related differences in levels of plasma retinol (2-fold higher in C male mice than in C or R female mice) are described. Aging was associated with trends towards lower levels of plasma ascorbate (14-25%), glucose (34-36%) and glycohemoglobin (47-57%) from 4.5 to 23 months of age. However, these age differences depended upon the diet and sex of the animals. These data suggest that lower plasma levels of glucose, glycosylated hemoglobin and cholesterol may be causally related to the life extension noted in R animals since elevated levels of these moieties have been related to aging. Since oxidative stress is thought to be causally related to aging it appears unlikely that retinol, tocopherol and ascorbate are causally related to R-induced life-extension.

Use of albumin as a predictor of mortality in community dwelling and institutionalized elderly populations

This study was undertaken to identify variables that could explain the association between low albumin and a 9- to 12-year mortality follow-up among 287 community- dwelling and 176 institutionalized people aged 60 years and over. A wide array of nutrition assessment variables was simultaneously examined in this population to identify confounders of the association. The results show that the risk of mortality for subjects with albumin values of 40 g/liter and over was 0.46 of the risk for those with albumin values below 40 g/liter, after controlling for the confounders age, blood urea nitrogen, triglyceride, history of diseases, and inability to shop owing to medical conditions. Similarly, albumin was also inversely associated with mortality among institutionalized subjects even after controlling for the confounders age, sex, blood urea nitrogen, transferrin, and history of stroke. However, the association was no longer significant among the institutionalized population once the deaths that occurred within the first 3 years after study participation were eliminated. The results indicate that albumin is a long-term predictor of mortality among noninstitutionalized subjects and increased mortality is not only a result of age, history of chronic diseases, medication use, or protein intake. Among institutionalized subjects, albumin appeared to be a short-term predictor of mortality.

Obesity and malnutrition in a Shantytown population in the city of São Paulo, Brazil

To investigate the prevalence of obesity and malnutrition in the poor Brazilian population we conducted a survey on the socioeconomic and nutritional status of 535 families (comprising 2,411 individuals) living in shantytowns in the city of São Paulo. There was a 30% prevalence of malnutrition in the children, with chronic malnutrition as the most predominant problem. The prevalence of obesity was 6.4% in boys and 8.7% in girls. Overweight and obesity associated with stunting was found in 5.8% of boys and 6.8% girls. Adolescents showed a higher prevalence of malnutrition when weight-for-age distribution was used (boys 46.4%, girls 40.2%), but a right deviation in the distribution was observed with an increase in obesity and a decrease of malnutrition was observed (obesity was 21% in girls and 8.8% in boys; malnutrition was 15.5% in boys and 12.6% in girls) when the weight-for-height adjustment was made. Stunting was the most predominant type of malnutrition in both sexes. Obesity associated with stunting was more common than obesity without stunting, both in younger children and adolescents. Adults had a higher prevalence of obesity than malnutrition according to both the Metropolitan Life Insurance tables (1.7% of undernutrition, 16.7% of overweight, and 14.1% of obesity) and Body Mass Index (8.5% of undernutrition, 21.9% of overweight, and 14.6% of obesity). There was an increase in the percentage of obese children when at least one adult in the family was obese and an increased percentage of malnourished children when undernourished adults were present in the family. Obesity among the adults of the family decreased the occurrence of malnutrition among the children.(ABSTRACT TRUNCATED AT 250 WORDS)

Dose-response characteristics of galactose-induced cataract in the rat

The onset and progression of cataract was investigated in weanling Sprague-Dawley rats fed 10, 15, 20 and 30% dietary galactose (groups 1-4) for 45-226 days. Cataracts were graded on a 0-5 scale. After 226 days, 9% of the rats fed 10% galactose developed lesions beyond the very early stage of cataractogenesis (grade 1). After 154 days 50% of the rats fed 15% galactose developed subcortical cataract (grade 3) with no nuclear cataract. In the rats fed 20% galactose, an initial rapid development by 31 days of a grade 3 cataract was observed in 50% of the eyes. Advancement to grade 4 and grade 5 cataract proceeded more slowly; by 207 days, 45% of the eyes had grade 5 cataract. In rats fed 30% galactose, rapid vacuolization and development of nuclear cataracts (grade 5) were observed by day 44. Dietary galactose at levels of 20 and 30% was associated with a significant reduction in weight gain at the early stage of dietary treatment. These observations demonstrate that 10-30% dietary galactose induces cataract in rat lens in a dose- and time-dependent fashion. These data serve to further establish this animal model as a useful model for studying the sequelae of cataractogenesis.

Calcium retention and hormone levels in black and white women on high- and low-calcium diets

Black-white differences in calcium metabolism are sought because they may reveal why blacks have higher bone mass than whites. Comparative studies of calcium absorption in blacks and whites are not available. In this study, we compare fractional calcium retention, an index of calcium absorption, and calcium regulating hormone levels in black and white women on a high-calcium diet and after adaptation to a low-calcium diet. A total of 30 healthy women (15 black and 15 white) had measurements of fractional 47Ca retention and calcium regulating hormone levels after 8 weeks on a 2000 mg calcium diet and, subsequently, after 1, 2, 4, and 8 weeks on a 300 mg calcium diet. By 2 weeks after the diet change, fractional 47Ca retention, parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D [1,25-(OH)2D] had reached a plateau at higher levels, urine calcium at a low level, and serum calcium at the same level (repeated-measures ANOVA). Fractional 47Ca retention, serum calcium, and PTH were similar on both diets in blacks and whites. Blacks had higher levels of 1,25-(OH)2D on both diets (e.g., 125.1 +/- 53.5 SD versus 73.4 +/- 19.0 pmol/liter, P = 0.003 on low-calcium diet) and a greater increase in 1,25-(OH)2D after the diet change (33.9 +/- 30.1 SD versus 11.8 +/- 17.9 pmol/liter, P = 0.021). Serum phosphorus was lower in blacks throughout. For hormone levels and fractional calcium retention to stabilize after a diet change, 2 weeks was needed.(ABSTRACT TRUNCATED AT 250 WORDS)

Test-retest reproducibility of the relative dose response for vitamin A status in Guatemalan adults: issues of diagnostic specificity

The relative dose response (RDR) test was examined with regard to specificity and reproducibility in subjects with adequate dietary intake and normal liver reserves of vitamin A. Twelve subjects were administered an RDR test four times over 22 d, including one placebo test in which the oral dose of vitamin A was omitted. Additionally, static measures of retinol, tocopherol, retinol binding protein (RBP) and prealbumin (PAL) were taken to determine the intra- and inter-individual coefficient of variation for these blood constituents. Intra-individual coefficients of variation were as follows: retinol, 8.8%; RBP, 11.5%; PAL, 7.6%; and alpha-tocopherol, 8.8%. The mean RDR in vitamin A-replete subjects was 1.2% and ranged from approximately -25% to 11%. No differences were observed between placebo and true RDR (i.e., with vitamin A) test responses, and there was no difference among the three true RDRs over a period of 22 d. Consistent with the hypothesis upon which the RDR test is based, nascently absorbed vitamin A evidently entered a storage pool in the liver of vitamin A-replete subjects without immediate release to peripheral sites of utilization. Because the RDR test results were normal in all subjects, the procedure appears to offer high test specificity and does not falsely diagnose hypovitaminosis A. Nevertheless, the magnitude and direction of the RDR within an individual over 22 d were highly variable, and this variability may preclude the use of a single measure of the RDR to grade the relative vitamin A nutriture of an individual subject.

Plasma lipoprotein cholesterol and endogenous sex hormones in healthy young women

Relationships between plasma levels of lipoproteins and sex hormones were studied in 24 healthy premenopausal women with no risk factors for coronary heart disease. The women were carefully selected to remove the effects of other environmental factors, such as smoking, drugs, alcohol, and exercise, which are known to influence lipid metabolism. They all ate precisely the same Western-style diet for 1 to 2 weeks before blood samples were obtained in the follicular phase of their menstrual cycle. After adjusting for other hormones by multiple regression, significant positive partial correlations were seen between high density lipoprotein cholesterol (HDL-C) and protein bound estradiol (r = .57, P = .02), as well as between very low density lipoprotein cholesterol (VLDL-C) and protein bound estradiol (r = .63, p = .01). A significant negative partial correlation was seen between VLDL-C and free estradiol (r = -.65 P = .01). Conversely, low density lipoprotein cholesterol (LDL-C) levels were negatively correlated with protein bound estradiol (r = -.77, P less than .001) and positively correlated with free estradiol (r = .71, P less than .001). No associations between plasma lipoproteins and testosterone were seen; however, androstenedione was positively correlated with VLDL-C (r = .59, P = .01). These findings show a close link between plasma lipoproteins and sex hormones, and may help to explain the lower risk of coronary heart disease in women.

Plasma lipoproteins in healthy octogenarians: lack of reduced high density lipoprotein cholesterol levels: results from the Framingham Heart Study

Genetic low density lipoprotein (LDL) deficiency and high density lipoprotein (HDL) excess have been associated with enhanced longevity. This investigation assessed the prevalence of lipoprotein abnormalities in octogenarians free of clinical evidence of cardiovascular disease (CVD) in the Framingham Heart Study. Plasma lipid and lipoprotein cholesterol determinations were carried out by standard techniques between 1971 and 1974. Participants who were free of clinical evidence of CVD in an examination approximately 10 years later (1981 to 1982) had their lipoprotein values tabulated based on the earlier examination. There were 106 women and 57 men who met these criteria, with mean ages of 83.3 and 82.9 years, respectively, at examination 16 (called cases). Mean levels (+/- SEM) of LDL cholesterol in cases were 152 +/- 3 mg/dL for women, and 147 +/- 5 mg/dL for men. For HDL cholesterol, these values were 57 +/- mg/dL for women and 46 +/- 2 mg/dL for men. These values were not statistically different from those of other study subjects (who did not meet the CVD criteria or were decreased) or middle-aged controls. In contrast, HDL cholesterol levels below the tenth percentile of normal were not observed in any male cases and in only 1.0% of female cases (P less than .05) as compared with observations in control subjects. The data are consistent with the concept that there is not an overrepresentation of either decreased LDL cholesterol or elevated HDL cholesterol values in subjects who subsequently become healthy octogenarians, but that these subjects are exceedingly unlikely to have reduced HDL cholesterol levels.

Bone density of the radius, spine, and hip in relation to percent of ideal body weight in postmenopausal women

Bone mineral content (BMC) and bone mineral density (BMD) of the spine (L2-L4) and hip (at femoral neck, Ward's triangle, and greater trochanter sites) were determined by dual-photon absorptiometry (DPA), and of the radius by single-photon absorptiometry (SPA) in healthy postmenopausal women aged 40-70 years. The relationships of BMC and BMD to years since menopause were examined separately in 97 women who were above 115% of ideal body weight (IBW) and in 128 women below. The heavier women had significantly greater mean BMC and BMD at each site than did the normal-weight women. In the normal-weight women, there was a significant negative correlation between BMD and years since menopause at each measurement site except the greater trochanter. In the obese women, BMD decreased with increasing years since menopause at the radius site only and BMC declined with increasing years after menopause at the hip (femoral neck and Ward's triangle region) as well as the radius. Thus, body size is a significant determinant of BMD in this population. The pattern of loss of BMD from Ward's triangle and femoral neck regions of hip are similar to that of the spine. The BMC and BMD findings in the hip suggest that remodeling occurs at this weight-bearing site which has a favorable effect on bone strength.