Energy, protein, zinc and copper status of twenty-one elderly inpatients: analysed dietary intake and biochemical indices

Dietary variety and its effect on food intake of elderly adults

BACKGROUND

Older people frequently have poor food intake. This present study investigated the effect of dietary variety on food intake in younger and older people.

METHODS

Eighteen young adults (mean age = 26 years) and 18 older adults (mean age = 70 years) consumed four consecutive courses of sandwiches on two occasions. In the plain treatment, each course of sandwiches was of the same type, while in the variety treatment four courses, each of a different type of sandwich, were served. Each time the participants were presented with a serving of sandwiches and asked to eat as much as they liked.

RESULTS

In the plain condition, the older adult group consumed more than their young counterparts. This situation was reversed for the variety condition when the young group ate more than the older adults. Interestingly, the older adult group ate more when a variety of sandwiches was presented. This may be contrary to what is predicted by the sensory-specific satiety model of eating behaviour.

CONCLUSIONS

This study suggests that presenting the older people with a varied meal may be a valid strategy to improve food intake in this group.

Effect of dietary phytic acid on zinc absorption in the healthy elderly, as assessed by serum concentration curve tests

Zn absorption was investigated in healthy elderly subjects aged 71–78 years and in young subjects aged 23–43 years using serum concentration curve (SCC) tests. Both groups had similar Zn and protein status. The increase in serum Zn was monitored for 180 min after ingestion of 200ml of soya milk enriched with 50mg of Zn. Three levels of phytic acid were used: 0g/200ml (totally dephytinized soya milk), 0.13 g/200ml (half dephytinized), and 0.26 g/200ml (natural phytic acid content). In a first study the effect of 0v.0.26 g/200 ml phytic acid was compared in 10 elderly and 10 young subjects, each subject receiving both treatments. In a second study soya milks with 0 and 0.13 g/200ml were tested in nine elderly and ten young subjects, again receiving both treatments. Mean areas under the curve of the SCC tests conducted with the 0 g/200 ml soya milk were found to be the same in both studies. Phytic acid strongly depressed Zn absorption in both studies (P≤ 0.05), but to a greater extent at the 0.26 g/200ml level. No difference was found between the groups of young and elderly subjects. Therefore, no significant effect of aging on Zn absorption, as evaluated by the SCC test, or on the inhibitory effect of phytic acid was detected.

Copper status and enzyme, hormone, vitamin and immune function in heifers

A survey was conducted in 10 districts of Northern India to record the copper deficiency in soil, fodder and serum samples. Significant deficiency of copper was observed in soil, fodder and serum samples of heifers. The copper deficient animals were listless, showed depigmentation of skin, stiff gait and were anaemic and diahorric. The purpose of the study was to evaluate the magnitude of copper deficiency in Northern India and to examine the various haematobiochemicals, enzymes, vitamin and immune function which are affected by the deficiency of copper, so as to identify the parameters which can be of diagnostic importance in copper deficiency. Forty hypocuperemic heifers were selected from these areas and were randomly divided into two groups A and B. The heifers in group A were provided with mineral mixture containing copper sulphate and in group B without copper sulphate. Significant improvement (P<0.01) was observed in the haemoglobin (Hb), total leukocyte count (TLC) and total erythrocyte count (TEC) level at the 30th day of treatment in the animals of group A. Significant (P<0.01) improvement in serum. Ceruloplasmin (Cp) level was observed within 30 days of treatment, while significant (P<0.01) improvement in monoamine oxidase and liver cytochrome oxidase was observed at the 60th day of treatment in group A animals. Regarding hormones significant improvement was observed in T(3) and T(4), in the animals of group A within 60 days of treatment. The values of vitamin A and E showed significant (P<0.01) improvement within 30th days of treatment. The phagocytic activity of neutrophils against Candida albicans significantly (P<0.01) improved in group A within 60 days of treatment. Similarly significant improvement in superoxide dismutase activity in RBC was observed at the 30th day, and WBC and whole blood at 60th day in group A animals. Significant improvement in liver Cu level was observed at the 30th day of treatment, while in group B the liver Cu was significantly (P<0.01) depleted at the 60th day of experimentation. Additional Cu supplementation improved growth performance significantly in group A.

Biomarkers of trace mineral intake and status

The emerging public health importance of zinc and selenium and the continuing public health challenges of iron and iodine draw attention to the unmet need for improved biomarkers of trace element status. Currently available biomarkers of these four trace elements are critiqued including the outstanding lack of satisfactory biomarkers for the assessment of zinc intake and status. Other trace elements are reviewed briefly including copper, for which human dietary deficiencies and excesses have been documented, and chromium, which is of possible but unconfirmed public health significance. Evolving strategies of considerable potential include molecular techniques such as the measurement of metallothionein mRNA in lymphocytes as a biomarker of zinc status, an assay that can now be performed with a dried blood spot. The judicious application of tracer techniques also has a role in advancing the quality of zinc biomarkers. Also of special current interest is full definition of the potential of plasma-soluble transferrin receptor concentrations as the biomarker of choice for the detection of early functional iron deficiency.

Nutrition, ageing and ill health

There are physical, mental, social and environmental changes which take place with ageing; for example, decreased physical activity, increase in body fat, decrease in lean body mass and consequently decreased energy intake may be associated with physiological functions that affect metabolism, nutrient intake, physical activity and risk of disease. There are now many studies which have found that undernutrition is prevalent and often unrecognized in patients admitted to hospitals and institutions. There is also evidence which links protein-energy undernutrition or its markers with clinical outcomes in acute and non-acute hospital settings and that nutritional supplements can improve outcomes in some of these settings. However, most clinically-available nutrition screening instruments lack sensitivity and specificity, and abnormal nutritional indicators may simply reflect effects of age, functional disability, or severe underlying disease. Thus, causal relationship cannot be assumed without a sufficiently powerful intervention study which adequately adjusts for the effects of non-nutritional factors, such as the number and severity of co-morbid conditions on clinical outcome.

Serum zinc levels in healthy subjects from southeastern Spain

The serum zinc (Zn) concentrations of 80 healthy subjects (48 male, 32 female) from southeastern Spain were determined by atomic absorption spectrometry. The samples were digested by heating in a 4:1 mixture of nitric and perchloric acids. The concentration of Zn was determined against a Contox Trace Metal Serum Control Panel A standard reference. Zn concentrations in the standard were found to be 2.332+/-0.489 mg/L, with a mean recovery of 102.7%. In the serum samples, the relative standard deviation was <6% for the range of concentrations determined: 0.420-1.540 mg/L for women (mean value 0.947+/-0.265 mg/L) and 0.490-1.480 mg/L for men (mean value 0.951+/-0.243 mg/L). In healthy subjects, no statistically significant differences were observed in the Zn levels with respect to their sex (p > 0.05) or the location where they lived (mountainous vs coastal zones). It is concluded that the dietary Zn intake and Zn status for healthy adults in this region of Spain are within normal values.

Serum concentration and dietary intake of Zn in healthy institutionalized elderly subjects

We determined the serum concentrations and dietary intake of zinc, as indicators of Zn status, in 44 healthy institutionalized elderly subjects in Granada (Spain) (mean age 81.4 +/- 7.9 years). Determination of Zn in serum was carried out by electrothermal atomic absorption spectrophotometry. Serum samples had a mean Zn concentration of 10.49 +/- 3.5 mumol/1. No significant differences were found in the serum levels of Zn as regards the sex of the subjects. However, concerning Zn intake, determined by a 7-day weighted food record, a significant statistical difference (P < 0.001) was found between men and women, with mean values of 10.01 +/- 1.76 mg/day and 7.33 +/- 1.33 mg/day, respectively. Application of regression analysis to the serum concentration of Zn and other nutritional parameters shows a statistically significant correlation (P < 0.05) between serum levels of Zn and the body mass index. The lack of statistical correlation between the serum concentration of zinc and its intake indicates that this index cannot be used as an indicator of zinc status in the elderly.

Determination of copper levels in serum of healthy subjects by atomic absorption spectrometry

Copper levels in serum samples of 84 healthy subjects living in southeastern Spain were determined using the flame atomic absorption spectrometry technique. Mineralization of samples was carried out with an HNO3/HClO4 (4:1) mixture in a thermostated mineralization block. The accuracy of the method was tested by using a standard reference material. A mean recovery percentage of 104.70% was obtained. The relative standard deviation (R.S.D.) as a measurement of the precision of the method was lower than 5% in the concentration range considered. Mean copper concentrations were 1.092 +/- 0.365 mg/l (with the range 0.304-2.000 mg/l) and 1.113 +/- 0.253 mg/l (corresponding to an interval of 0.648-1.760 mg/l) for women and men, respectively. There are no significant differences between the copper levels in serum according to either sex or geography zone (P > 0.05). For example, there were no differences of copper levels in serum of subjects from coastal and mountainous zones. Estimated daily dietary intakes on copper in women and men were 1.38 and 2.10 mg Cu/day respectively.

Nutritional support and functional status in undernourished geriatric patients during hospitalization and 6-month follow-up

The objective of this study, designed as a randomized controlled prospective intervention study, was to evaluate the effect of nutritional supplementation on functional status and need of care in undernourished geriatric patients during hospitalization, and up to 6 months after discharge. Participants consisted of 46 undernourished geriatric patients from a geriatric acute care hospital aged 75 years or older without malignant disease, or need for tube feeding or parenteral nutrition. Patients in the supplement group (SG, N = 20) were offered 400 mL (2100 kJ) daily of a liquid supplement during hospital stay and 200 mL (1050 kJ) per day for the following 6 months at home. Patients in the control group (CG, N = 26) had usual care without supplements. The main outcome measure was functional status based on the Barthel Activities of Daily Living score (ADL) at hospital admission, discharge and after 6 months, with higher scores indicating greater independence and a maximum score of 100 points. In supplemented patients with good acceptance (SG+, N = 11), a median improvement of 20 points was observed between admission and discharge, and a further improvement of 5 points at home. Median changes were 0 and -10 points in supplemented patients with poor acceptance (SG-, N = 9) and 5 and 2.5 points in CG, respectively. In SG+, the proportion of independent patients (> 65 points) increased continuously from 36% at admission to 63% at discharge, to 72% after 6 months, and was significantly higher compared to CG at discharge (63% vs 19%, p < 0.05) and after 6 months (72% vs 39%, p < 0.05). 64% of the patients in SG+ improved during hospitalization, compared to 23% in CG (p < 0.05). In the six months at home, 18% of SG+ improved; none of SG+ deteriorated in hospital or at home. In contrast, deterioration of the ADL score occurred in considerable proportions of SG- (22% in hospital, 22% at home) and CG (4% at hospital, 12% at home) patients. The proportion of patients who improved was smaller in SG- (44% at hospital, 22% at home) as well as in CG (23% at hospital, 35% at home), compared to SG+. In conclusion, a positive functional course was evident in supplemented patients with good acceptance during hospitalization, and further improvement was observed during the following 6 months at home. Nutritional support may contribute to reconvalescence and recovery of undernourished geriatric patients.

Energy intake and expenditure in elderly patients admitted to hospital with acute illness

Studies on hospitalized elderly subjects have demonstrated that negative energy balance is common during hospitalization, but have concentrated primarily on long-stay and psychogeriatric patients. There is little information on energy balance in elderly patients admitted with acute illness from the community, despite the importance of this patient group and the presence of a number of factors likely to predispose such patients to negative energy balance. In the present study energy balance was quantified in twenty patients (eight males, mean age 82 (SD 5) years; twelve females, mean age 84 (SD 6) years) admitted from the community with acute illness, and predicted basal metabolic rate (BMR) was compared with measured resting metabolic rate (RMR). Most patients were in negative energy balance during hospitalization, and median measured energy intake (EI): measured RMR ratio was 1.0 (range 0.7-1.8). The mean difference between measured EI and estimated total energy expenditure was -1.3 MJ/d (range -3.4 to +2.5 MJ/d). Estimated total energy expenditure exceeded measured EI in fifteen of the patients and there was a significant decline in mid-arm muscle circumference (paired t, P < 0.05) during hospitalization. We conclude that moderate negative energy balance is common in this patient group, and that these patients are at risk of undernutrition during their hospital stay.

The importance of dietary protein in healing pressure ulcers

OBJECTIVE

To determine the effect of dietary protein on healing of pressure ulcers in malnourished patients.

DESIGN

Nutritional intervention trial with the non-randomized assignment of patients by pressure ulcer stage and bed type.

SETTING

Long-term care facility.

PATIENTS

Twenty-eight malnourished patients (age = 72 +/- 18 years, mean +/- SD) with a total of 33 truncal pressure ulcers. Nine patients had stage II ulcers, eight had stage III ulcers, and 16 had stage IV ulcers.

METHODS

Patients received liquid nutritional formulas as tubefeedings or meal supplements containing either 24% protein (61 g protein/L; n = 15) or 14% protein (37 g protein/L; n = 13) for 8 weeks.

RESULTS

There was a significant decrease in total truncal pressure ulcer surface area of the 15 patients in the 24% protein group (-4.2 +/- 7.1 cm2, P < 0.02), but not in the 13 patients in the 14% protein group (-2.1 +/- 11.5 cm2, P = NS). The change in total ulcer area correlated with both dietary protein intake per kg body weight (rs = -0.50, P < 0.01) and caloric intake per kg body weight (rs = -0.41, P < 0.03). The decrease in stage IV ulcer area in eight patients in the 24% protein group (-7.6 +/- 5.8 cm2, P < 0.02) was significantly greater (P < 0.05) than in eight patients in the 14% protein group (-3.2 +/- 16.4, P = NS). In these 16 patients, the decrease in ulcer size also correlated with dietary protein intake per kg body weight (rs = -0.63, P < 0.01).

CONCLUSION

High protein diets may improve the healing of pressure ulcers in malnourished nursing home patients.

Antioxidant status (selenium, vitamins A and E) and aging

Antioxidant status can be evaluated by blood selenium, vitamins A and E. The level of selenium was determined in whole blood, erythrocytes and plasma of 170 French people (70-95 years old) healthy and with intercurrent illness, by using PIXE (proton-induced X-ray emission analysis). These results are discussed with other values from the literature. Plasma levels of vitamins A and E have been measured by HPLC. All data were compared with those obtained for younger subjects. Healthy elderly people residing in a geriatric home received selenium supplements during 1 month. The influence of this supplementation brought to light a deficiency for this trace element. The correlation of aging and nutritional requirements with immune function, heart and cancer death rate is presented and discussed.

Effects of copper status on neutrophil function, superoxide dismutase, and copper distribution in steers

Twelve Holstein steers in a completely randomized block design were fed either a basal diet (concentrate:silage or hay at a DM ratio of 35:65) plus Cu sulfate at 20 ppm of Cu (Cu-supplemented diet) or a basal diet plus ammonium molybdate to obtain 10 ppm of Mo (Cu-depleting diet) on a DM basis in the whole diet for 8 mo. Supplemental Mo was utilized in the Cu-depleting diet to develop a Cu-deficient group. Molybdenum slowly accumulated in the liver in the group fed the Cu-depleting diet. Copper concentrations in the liver and polymorphonuclear neutrophils decreased in the Cu-deficient group compared with the Cu-sufficient group. Plasma Cu concentration did not change during the trial for the Cu-sufficient group. In the Cu-deficient group, plasma Cu concentrations increased during the first 3 mo of the trial, then declined, and remained unchanged for the last 5 mo. Superoxide dismutase activities in red blood cells, polymorphonuclear neutrophils, and whole blood decreased in the Cu-deficient group. Phagocytic capacity was not affected by Cu status, but killing capacity was decreased by low Cu status in the Cu-deficient group by the end of the trial. Glutathione peroxidase activity was unaffected by Cu status. Clinical symptoms of Cu-deficiency were not observed in this trial; there was no evidence of blood hemoglobin or BW gain difference between the two groups. In this study, Cu status affected its distribution in the tissues and related enzyme activities as well as bactericidal function of neutrophils.

Selenium and vitamin E status of healthy and institutionalized elderly subjects: analysis of plasma, erythrocytes and platelets

Levels of selenium in whole blood, plasma, erythrocytes and platelets, glutathione peroxidase (EC 1.11.1.9; GSH-Px) activity in erythrocytes and platelets and vitamin E, low-density-lipoprotein (LDL)-cholesterol and vitamin E: LDL cholesterol in plasma were measured in seventy-five healthy subjects aged less than 65 years and twenty-eight healthy and twenty-three institutionalized elderly people aged greater than 65 years. Healthy elderly subjects had significantly lower levels of Se in whole blood and plasma when compared with younger subjects. Other measurements of Se status were not significantly different. In the healthy subjects plasma levels of vitamin E and LDL-cholesterol increased with age to 60 years and decreased above 80 years. Vitamin E: LDL cholesterol values were not affected by age. Measurements of Se and vitamin E status in the institutionalized elderly compared with the healthy elderly were all reduced with the exception of platelet Se levels and erythrocyte GSH-Px activity. Ageing per se had minimal effect on Se and vitamin E status but intercurrent illness and decreased food intake can lead to reduced levels in the elderly.

Calcium, magnesium and phosphorus status of elderly inpatients: dietary intake, metabolic balance studies and biochemical status

The calcium, magnesium and phosphorus status of a group of elderly inpatients was studied by use of duplicate meal analysis over a 5 d period and biochemical indices in twenty-one patients, and metabolic balance (5 d) in six of these. Mean daily Ca intake was lower than that of apparently healthy elderly subjects in metabolic equilibrium, although commensurate with present UK recommendations. Metabolic balance was negative for Ca. Mean daily Mg intake was approximately half the US recommendation, and half the intake at which metabolic balance has been observed in healthy elderly people. The five patients studied were in metabolic balance for Mg. Mean daily P intake was close to the UK recommendation, but negative metabolic balance was observed. The disparity between official recommendations for Ca-intake, factors contributing to suboptimal Ca status, and measures that may improve Ca status in this group are discussed.