About half the residents living in nursing homes and homes for the elderly show activity factor values less than 0.25 in daily living. However, the current Recommended Dietary Allowances (RDA) have been intended to apply to self-supporting and healthy elderly persons rather than bedridden elderly persons. Accordingly, current RDA tables do not indicate energy requirements for frail elderly people who show less values than 0.25 in activity factor. Consequently, in most institutions for the elderly, an adequate dietary energy supply for residents has been calculated on the basis of “level I (light)” in levels of physical activities. In this study, we measured the daily energy expenditures of 78 frail elderly females (age; 79.9±7.1yrs) living in nursing homes and homes for the elderly. From these results, energy requirements for frail elderly females corresponding with 0.00 to 0.25 of the activity factor were provisionally estimated as to be 21 to 31kcal/kg BW.
Age is one of the most important factor of changes in energy metabolism. The basal metabolic rate decreases almost linearly with age. Skeletal musculature is a fundamental organ that consumes the largest part of energy in the normal human body. The total volume of skeletal muscle can be estimated by 24-hours creatinine excretion. The volume of skeletal musculature decreases and the percentage of fat tissue increases with age. It is shown that the decrease in muscle mass relative to total body may be wholly responsible for the age-related decreases in basal metabolic rate. Energy consumption by physical activity also decreases with atrophic changes of skeletal muscle. Thus, energy requirement in the elderly decreases. With decrease of energy intake, intake of essential nutrients also decreases. If energy intake, on the other hand, exceeds individual energy needs, fat accumulates in the body. Body fat tends to accumulate in the abdomen in the elderly. Fat tissue in the abdominal cavity is connected directly with the liver through portal vein. Accumulation of abdominal fat causes disturbance in glucose and lipid metabolism. It is shown that glucose tolerance decreases with age. Although age contributes independently to the deterioration in glucose tolerance, the decrease in glucose tolerance may be partly prevented through changes of life-style variables, energy metabolism is essential for the physiological functions. It may also be possible to delay the aging process of various physiological functions by change of dietary habits, stopping smoking, and physical activity.
It is generally accepted that decreased lean body mass (LBM) with aging is responsible for decline in basal metabolism (BMR) of the elderly. However, multiple regression analysis of BMR and related factors for middle- to older-aged subjects showed that decline in BMR with aging could not be explained only by decrease in LBM. Basal heat production rates per essential body mass (EBM) and per fat tissue mass (FTM) by sex and by age class were estimated using the regression analysis proposed by Chirifu. It was found that the basal heat production per EBM decreased with aging, indicating that both decreases in active tissue mass and BMR per unit of active tissue mass were involved in reduced BMR for the elderly. A 15-week aerobic exercise training course prescribed for mildly obese middle- to older-aged women improved their fitness level and body composition, i.e., decrease in FTM with increase in EBM. The basal heat production rate per EBM increased by 21%. These results suggest that aerobic exercise training is effective for improving the metabolism of active tissue in the middle-aged and the elderly. Although there was a wide inter-individual variation in BMR in the elderly over 70 years of age, the BMR tended to increase depending on the level of daily activity. In conclusion, physical exercise and an active daily life are important for decelerating the decrease in BMR for the elderly through maintaining active tissue mass and its basal metabolism
The relation between habitual exercise and the basal metabolic rate, energy expenditure during exercise (lactic threshold and maximal oxygen uptake) was examined in 291 older people. Metabolic rate was highest in old players of gatebowl (a form of croquet) (male; 23.3±2.3, female; 22.7±3.0kcal/kg/day), higher in old untrained people (male; 21.9±2.5, female; 20.8±2.4kcal/kg/day), and lower in old people in a home for the aged (male; 20.6±3.5, female; 20.8±3.7kcal/kg/day). Energy expenditure while walking at a speed of less than 100m/min was similar in trained and untrained old people aged 60-69 years. However, lactic threshold was higher in trained (30.2±4.8ml/kg/min) than in untrained (20.9±2.8ml/kg/min) females aged 60-69 years. Maximal oxygen uptake was higher in trained (male; 50.4±4.1, female; 36.6±3.9) than in untrained (male; 30.9±3.7, female; 26.8±2.8) old people aged 60-69 years. It was suggested that a higher basal metabolic rate, lactic threshold and maximal oxygen uptake resulted in higher daily physical activity and larger daily energy consumption in trained old people.
In order to study nutritional asessment and nutritional support therapy for elderly patients, we conducted energy supply therapy on 15 elderly (aged over 75) patients disabled with diseases such as cerebrobascular disease, pneumonia and heart failure. After recovery from acute phase, they were divided into 3 groups, and assigned to 3 different energy supply methods for 2 weeks: Six (3 males, 3 females) could take hospital diet, but only could absorb about 50% of the energy, amounting only 1, 000 to 1, 400kcal/day. Additional 246kcal was given by peripheral parental nutrition (PPN). Five (2 males, 3 females) were unable to take nutrition orally. Therefore, they were given high caloric nutrients by total parental nutrition (TPN). giving (1, 222kcal daily for a week), then 1, 666kcal for another week. Four (1 male, 3 females) also could not take meals orally, and had to be nourished by enteral nutrition (EN) with a nutrient preparation of 1, 120kcal for one week, then with 1, 600kcal for another week. In all 3 groups, the indeces of rapid turnover proteins (pre-albumin, retinol binding protein and transferrin), choline esterase and vitamin A significantly elevated after 2 weeks of therapy, though the increase of pre-albumin and RBP in TPN group was slightly below the significant level. The increase in rapid turnover proteins and choline esterase was greater in the order of EN, TPN and PPN. Vitamin C, on the other hand, decreased significantly with treatment in alll the groups, while vitamin E remained unchanged. The other nutritional indices: such as body weight, triceps skinfold thickness, arm muscle circumference, total protein, albumin, serum lipids, aplipoproteins and branched amino acid contents did not change significantly during the period of this study. These results indicate that 1) for nutritional assessment, rapid turnover proteins, choline esterase and vitamins A and C are more sensitive even to the nutritional treatment for 2 weeks. 2) for nutritional improvement in the elderly, nutritional preparations closer to values of a balanced diet are preferable, and more effective when delivered via digestive tract.
Hyperinsulinemia has been closely associated with hypertension in several epidemiological studies, but little is known about this condition in the elderly. The authors studied the relationship between serum insulin and blood pressure levels, and the prevalence of hypertension according to insulin levels in the elderly in a Japanese rural community, Hisayama. In 1988, 75g oral glucose tolerance test was performed on 426 male and 567 female Hisayama residents aged 60 to 79 years. Fasting and 2hr serum insulin values were measured by radioimmunoassay. In the subjects, excluding those receiving antihypertensive drugs, the sum of fasting and 2hr postload insulin (ΣIRI) significantly correlated with systolic (r=0.15 and 0.25 for males and females, respectively) and diastolic blood pressure (r=0.20, 0.16). In multiple regression analyses, the correlation with systolic blood pressure remained significant in females after controlling for age, body mass index, alcohol intake, smoking habits, serum total cholesterol, HDL-cholesterol, triglycerides, and fasting plasma glucose. In contrast, ΣIRI did not remain as an independent variable relevant to blood pressure among males. The age-adjusted prevalence rates of hypertension (≥160/95mmHg or receiving drug treatment) significantly increased with increasing quartiles of ΣIRI in females. The prevalence of hypertension which was not treated with drugs also increased significantly with increasing ΣIRI in females. However, no significant association was observed in males. In conclusion, the present study suggests that hyperinsulinemia can be related to hypertension in the female elderly in the general population of Japan.
The authors investigated causes for weight loss in inpatients with senile dementia, who could take diets. The 81 patients (80±8.3 years of mean age±S.D., 22 males and 59 females) included 48 cases of senile dementia of Alzheimer type (SDAT) and 25 cases of multi-infarct dementia (MID). Controls consisted of 77 non-demented patients (82±9.1 years, 29 males and 48 females) who were admitted because of cerebrovascular or cardiopulmonary diseases. Demented patients showed an average of -1.8±8.5% weight change per year, while that of non-demented patients was +4.4±6.3%, resulting in a significant difference between them (p<0.0001). Between demented males and females, there was no significant difference. In male, SDAT cases showed more weight loss than MID cases (-5.0±5.1% vs +3.3±4.2%, P=0.003), although in females there was no significant difference between SDAT and MID. Even when patients with a wandering tendency or complications were excluded, results essentially did not change. In demented patients, weight change did not correlated with age, amount of dietary intake, length of hospital stay or serum albumin level. However, it correlated with body weight (r=0.26, P=0.014), ADL index (GBS-A) (r=0.22, P=0.04), and with Mini-Mental State Examination score (r=0.23, P=0.048). In multiple regression analysis, the most powerful explanatory variable in demented males was the index for cerebral atrophy. These results confirmed previous studies reporting that reduced dietary intake, complications or hyperactivity do not fully explain weight loss in demented patients. Furthermore, we demonstrated that weight loss was marked in SDAT males and it correlated with severity of dementia and cerebral atrophy, suggesting that some intrinsic factor(s) for weight loss should be considered.
We measured mean blood flow velocity (MFV) and Fourier pulsatility index (PI) of the M1 portion of the middle cerebral artery (MCA) by transcranial Doppler mapping technique (2MHz, Trans-scan, EME Co., Ltd.). The correlations between these parameters and arteriosclerotic risk factors such as aging, hypertension and diabetes mellitus were examined. Healthy volunteers as well as patients suffering from hypertension and diabetes mellitus were studied. A total of 59 persons (85MCAs) consisting of 30 males (mean age 54.4, 24-81 years) and 29 females (mean age 54.8, 20-75 years) were enrolled in this study. Some hypertensive or diabetic subjects had previous cerebrovascular disease, therefore cases who had only minor stroke or asymptomatic infarction without significant lesions in carotid artery system were included. After excluding brain embolism, these subjects were divided into three groups as normotensive/non diabetic group (NT/non DM), hypertensive group (HT) and diabetic group (DM). In each group, MFV decreased with aging, being more evident in the HT and DM groups than in the NT/non DM group. Fourier PI also showed a significant increase with aging, and the correlation was stronger than that between MFV and age. Moreover, these trends of age-Fourier PI relationship were more highly significant in HT and DM groups than NT/non DM group. In cases with HT or DM, age-related arterial changes appeared to be more severe than in those without. Fourier PI seemed valuable for detecting aterial lesions with aging, HT and DM.
The severity and frequency of atherosclerosis, diabetes, and ischemic heart disease, which affect cardiac function, increase with aging. Although there are many reports about hemodynamic and histpathological studies about aging hearts, there are very few studies on changes in structural proteins in aging hearts. We investigated the contractile proteins of the left ventricles in rats aged 6, 12 and 125 weeks using two-dimensional electrophoresis. There were no difference in structural proteins in heart between 6-week and 12-week-old rats. The contents of myosin heavy chain, myosin light chain 2, actin, troponin-I in 125-week-old rats decreased compared with those of 12-week-old rats. Myosin heavy chain, which is one component of myosin, interacts with actin and changes chemical energy to mechanical energy. Therefore its decrease leads to a decline in myocardial contractility. These results seem to indicate one of the most important changes in the aging rat heart, as well as impairment in relaxation by the increase of interstitial fibrosis and decline of Ca uptake by sarcoplasmic reticulum.
Recently, high frequencies of glucose intolerance and insulin resistance have been reported in patients with hypertension. However, both blood pressure and glucose tolerance are influenced by age. To investigate the effect of age on the interaction between blood pressure and glucose tolerance, we analyzed blood pressure and glucose tolerance in otherwise healthy subjects (n=576) who underwent an oral glucose tolerance test and blood pressure measurement as a part of a healthy care program. The prevalence of DM and IGT were significantly higher in the hypertensive group than in the normotensive group. When the subjects were divided into three groups according to their age (less than 50 years old, between 50 and 60 years old and more than 60 years old), the prevalence of glucose intolerance (DM or IGT) was significantly higher in the hypertensive group than in the normotensive group in subjects under 50 years old, but not in subjects between 50 and 60 years old or over 60 years old. In the subjects classified as having normal glucose tolerance, the incremental area of glucose under the curve of 75g-OGTT was significantly higher in the hypertensive group than in the normotensive group. These data suggest that hypertension is associated with glucose intolerance in Japanese population and that age significantly affects this interaction.
The authors experienced two elderly patients of megacolon associated with cerebral infarction and diabetes mellitus. The first patient was a 66-year-old female who was admitted to our hospital for rehabilitation with a complaint of knee pain. She had suffered from diabetes mellitus since she was 30 years old and multiple cerebral infarction since age 62. Two months after admission, she had an episode of abdominal distension and obstructive symptoms. The roentgenograms of her abdomen showed diffuse dilatation of the colon. The second patient was a 78-year-old female admitted to our hospital with complaints of abdominal pain, distension of the abdomen and vomiting. Her abdomen was severely distended and plain roentgenograms of the abdomen, X-ray studies of the colon with the aid of contrast medium and CT scan of the abdomen showed striking dilatation of the colon. Megacolon may be congenital or acquired, and in acquired forms the conditions are secondary to organic diseases, smooth muscle atrophy, metabolic and neurological diseases, ulcerative colitis or phychogenic origin (idiopatic). The two patients in this series were suffered from cerebral infarction and diabetes mellitus. The mechanisms of megacolon seen in these two patients are not known, but involvement of the visceral autonomic innervation is presumed. Some elderly patients have chronic constipation, and dilatation of the colon may not be uncommon due to underlying diseases or drugs. Therefore, when examining elderly patients, careful attention should be paid to their bowel movement.