Aging is associated with a reduction in appetite and food intake, predisposing to protein-energy malnutrition. The causes of this “anorexia of aging” are largely unknown. To investigate possible ...contributions of enhanced satiating effects of cholecystokinin (CCK) and reduced stimulation of food intake by ghrelin, eight undernourished older women age, 80.4 ± 2.6 yr; body mass index (BMI), 16.9 ± 0.57 kg/m2, eight well-nourished older women (age, 77 ± 0.9 yr; BMI, 23.7 ± 0.8 kg/m2), and eight well-nourished young women (age, 22 ± 1.3 yr; BMI, 20.5 ± 0.4 kg/m2), in randomized order, ate on 1 d a 280-kCal preload and on the other no preload, 90 min before an ad libitum meal. At baseline the undernourished, but not the well-nourished, older subjects were less hungry (P < 0.05) than young subjects. Before and after the preload, plasma CCK levels were higher (P < 0.05) in the older than young subjects, with no difference between the older groups. Plasma ghrelin concentrations were higher in the undernourished than both well-nourished groups and decreased similarly after the preload in all groups. The preload suppressed food intake in the well-nourished older and young subjects (P < 0.05), but was without effect in the undernourished old. These observations suggest that reduced basal hunger, rather than increased meal-induced satiety, contributes to the anorexia of aging and that changes in CCK and ghrelin are unlikely to be responsible.
Healthy aging is associated with reductions in appetite and food
intake—the so-called anorexia of aging, which may predispose to
protein-energy malnutrition. One possible cause of the anorexia of
...aging is an increased satiating effect of cholecystokinin (CCK). To
investigate the impact of aging on the satiating effects of CCK, 12
young and 12 older healthy subjects received 25-min iv infusions of
saline (control) and CCK-8, 1 ng/kg per min or 3 ng/k per min, on 3
separate days before a test meal. Older subjects ate less than young
subjects, and food intake was suppressed 21.6% by CCK-8, compared with
the control day (P < 0.05). The suppression of
energy intake by CCK-8 in older subjects was twice that in young
subjects (32 ± 6% vs. 16 ± 6%
sem, P < 0.05) and was related to
plasma CCK-8 concentrations, which were higher at baseline
(P < 0.05) and increased more during CCK-8
infusions in older than young subjects (P < 0.01).
The extent of suppression of food intake per given rise in plasma CCK-8
concentrations did not differ between the two age groups
(P = 0.35). Endogenous CCK concentrations were
higher at baseline in older subjects (P < 0.001)
and decreased during the CCK-8 but not control infusions
(P < 0.01), suggesting that CCK suppresses its own
release. Plasma leptin concentrations were not affected by CCK
infusion, whereas postprandial insulin concentrations were lowered and
the peak postprandial glucose concentration was delayed but not
affected by CCK-8 infusion. Because older people retain their
sensitivity to the satiating effects of exogenous CCK and plasma
endogenous CCK concentrations are higher in older people, increased CCK
activity may contribute to the anorexia of aging.
Aging is associated with a decrease in appetite and a slowing of gastric emptying. The gastrointestinal hormones cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), and peptide YY (PYY) may ...mediate these changes.
We investigated whether aging influenced the secretion of CCK, GLP-1, and PYY and their effects on appetite and pyloric motility.
Eight healthy older (65–80 y) and 7 younger (20–34 y) men received isoenergetic (12.1 kJ/min) intraduodenal infusions of lipid and glucose for 120 min on separate days. Plasma CCK, GLP-1, and PYY concentrations were measured.
Plasma CCK concentrations were higher in older than in younger subjects (P = 0.004) as a result of higher baseline values (4.7 ± 0.2 compared with 3.2 ± 0.2 pmol/L; P < 0.0001) and a greater rise during lipid infusion (increase from baseline: 7.1 ± 0.5 compared with 5.3 ± 0.6 pmol/L; P = 0.048). Plasma GLP-1 and PYY concentrations were not significantly different between groups. The decrease in hunger during intraduodenal lipid infusion was inversely related to the increase in CCK, GLP-1, and PYY in younger but not older subjects. During intraduodenal lipid infusion, the increase in isolated pyloric pressure wave (IPPW) frequency was positively related to GLP-1 and PYY and the increase in IPPW amplitude was positively related to CCK in older but not younger subjects, whereas the increase in IPPW amplitude and pyloric tone was negatively related to GLP-1 and PYY in younger subjects.
Human aging is associated with increased CCK concentrations, which may contribute to the slowing of gastric emptying, mediated by increased pyloric motility. The role of increased plasma CCK concentrations in mediating the age-related decrease in appetite remains to be established.
Inclusion of fat reduces the glycemic response to a carbohydate meal, although the effect of different types of fat on glycemic, insulinemic and satiety responses is unclear. Ten healthy men received ...50-g carbohydrate portions of mashed potato with isoenergetic amounts of butter (saturated fatty acid), Sunola oil (monounsaturated fatty acid) or sunflower oil (PUFA) and two 50-g glucose loads on separate days. Capillary blood was collected at regular intervals for 2 h. Satiety ratings were assessed by use of a rating scale. The glycemic index (GI), insulin index (II) and satiety index (SI) scores were calculated. Energy intakes from a meal consumed ad libitum at 2 h and for the remainder of the day were quantified. The GI values ranged from 68 ± 8 to 74 ± 10 and the II values ranged from 113 ± 10 to 122 ± 17, but there was no effect of fat type. SI scores and subsequent energy intake did not differ among the test meals. Substitution of unsaturated fats for saturated fatty acids had no acute benefits on postprandial glycemia, insulin demand or short-term satiety in young men.
The anorexia of ageing CHAPMAN, Ian M; MACINTOSH, Caroline G; MORLEY, John E ...
Biogerontology (Dordrecht),
2002, 2002-00-00, 20020101, Letnik:
3, Številka:
1-2
Conference Proceeding, Journal Article
Recenzirano
Ageing is associated with a reduction in appetite and food intake, which has been termed the 'anorexia of ageing'. After age 70-75 years average body weight decreases, even in healthy people, ...disproportionately due to loss of lean tissue. The 'physiological' anorexia and weight loss of ageing predispose to pathological weight loss and malnutrition. Marked weight loss is common in the elderly and a major cause of morbidity and increased mortality. The cause(s) of the anorexia of ageing are largely unknown. We have identified several possibilities. Animal and preliminary human studies indicate that ageing is associated with increased satiety factors and a reduced feeding drive. Endogenous opioids stimulate eating. We administered i.v. infusions of the opioid antagonist naloxone to young and older adults. Overall, the suppression of food intake was not different in the two age groups, but was increased in older women, suggesting reduced stimulation of feeding by endogenous opioids in this group. Plasma concentrations of the satiety hormone cholecystokinin (CCK) increase with ageing. Intravenous CCK-8 infusion produced greater suppression of food intake in older than young subjects (33.5 vs 15.5% P = 0.026), indicating that sensitivity to the satiating effects of CCK is at least maintained and may increase with age. This raises the possibility of using CCK antagonists as stimulants of appetite and food intake in malnourished older people.
OBJECTIVES: To determine whether aging is associated with a reduction in the opioid modulation of feeding, which may be important in the pathogenesis of the “anorexia of aging.”
DESIGN: Three studies ...on separate days, in randomized order and double‐blind fashion.
SETTING: Clinical Human Research Laboratory, Department of Medicine, RAH, Adelaide, Australia.
PARTICIPANTS: Twelve older (5 male/7 female) (age 65–84) and 12 young (5 male/7 female) (age 20–26) healthy subjects.
INTERVENTION: Subjects received in double‐blinded random order, intravenous bolus (10 minutes) and then continuous (140 minutes) infusions of saline (control), naloxone low dose (LD) (bolus 27 μg/kg; continuous 50 μg/kg/hr), or naloxone high dose (HD) (bolus 54.5 μg/kg; continuous 100 μg/kg/hr).
MEASUREMENTS: After 120 minutes, subjects were offered a buffet meal, and their energy intake was quantified. Hunger, fullness, nausea, and drowsiness were assessed using visual analogue scales.
RESULTS: The naloxone LD and HD infusions had no significant effect on ratings of hunger, fullness, or nausea, but increased drowsiness (P < .01) compared with the control infusion in both age groups. Older subjects ate less (P < .001) at the buffet meal than young subjects during all three infusions. Naloxone infusions reduced energy intake compared with control (P < .001), LD by 13.2 ± 5.0% and HD by 10.7 ± 5.0%, with no difference between the doses (P = .71). Overall, naloxone suppressed energy intake in both young and older subjects (P < .01). This suppression was slightly, but not significantly, greater in young than in older subjects (mean of LD and HD 16.4 ± 4.9% vs 7.5 ± 4.9%, P = .42), because of a trend to reduced suppression in older women.
CONCLUSIONS: We conclude that healthy older adults retain their sensitivity to the suppressive effects of naloxone on food intake. Possible gender differences in this sensitivity warrant further investigation. A decline in opioid activity is unlikely to contribute substantially to the physiological anorexia of aging observed in older people.
Falls are a major cause of morbidity among older people. Multifaceted interventions may be effective in preventing falls and related fractures.
To evaluate the cost-effectiveness alongside the ...REducing Falls with Orthoses and a Multifaceted podiatry intervention (REFORM) trial.
REFORM was a pragmatic multicentre cohort randomised controlled trial in England and Ireland; 1,010 participants (> 65 years) were randomised to receive either a podiatry intervention (n = 493), including foot and ankle strengthening exercises, foot orthoses, new footwear if required, and a falls prevention leaflet, or usual podiatry treatment plus a falls prevention leaflet (n = 517).
incidence of falls per participant in the 12 months following randomisation.
proportion of fallers and quality of life (EQ-5D-3L) which was converted into quality-adjusted life years (QALYs) for each participant. Differences in mean costs and QALYs at 12 months were used to assess the cost-effectiveness of the intervention relative to usual care. Cost-effectiveness analyses were conducted in accordance with National Institute for Health and Clinical Excellence reference case standards, using a regression-based approach with costs expressed in GBP (2015 price). The base case analysis used an intention-to-treat approach on the imputed data set using multiple imputation.
There was a small, non-statistically significant reduction in the incidence rate of falls in the intervention group (adjusted incidence rate ratio 0.88, 95% CI 0.73-1.05, p = 0.16). Participants allocated to the intervention group accumulated on average marginally higher QALYs than the usual care participants (mean difference 0.0129, 95% CI -0.0050 to 0.0314). The intervention costs were on average GBP 252 more per participant compared to the usual care participants (95% CI GBP -69 to GBP 589). Incremental cost-effectiveness ratios ranged between GBP 19,494 and GBP 20,593 per QALY gained, below the conventional National Health Service cost-effectiveness thresholds of GBP 20,000 to GBP 30,000 per additional QALY. The probability that the podiatry intervention is cost-effective at a threshold of GBP 30,000 per QALY gained was 0.65. The results were robust to sensitivity analyses.
The benefits of the intervention justified the moderate cost. The intervention could be a cost-effective option for falls prevention when compared with usual care in the UK.
The aims of this study were to evaluate the effects of dietary glucose supplementation on gastric emptying (GE) of both glucose and fat, postprandial blood glucose homeostasis, and appetite in eight ...older subjects (4 males, 4 females, aged 65--84 yr). GE of a drink (15 ml olive oil and 33 g glucose dissolved in 185 ml water), blood glucose, insulin, gastric inhibitory polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), and appetite (diet diaries, visual analog scales, and food intake at a buffet meal consumed after the GE study) were evaluated twice, after 10 days on a standard or a glucose-supplemented diet (70 g glucose 3 times a day). Glucose supplementation accelerated GE of glucose (P < 0.05), but not oil; there was a trend for an increase in GIP (at 15 min, P = 0.06), no change in GLP-1, an earlier insulin peak (P < 0.01), and a subsequent reduction in blood glucose (at 75 min, P < 0.01). Glucose supplementation had no effect on food intake during each diet so that energy intake was greater (P < 0.001) during the glucose-supplemented diet. Appetite ratings and energy intake at the buffet meal were not different. We conclude that, in older subjects, glucose supplementation 1) accelerates GE of glucose, but not fat; 2) modifies postprandial blood glucose homeostasis; and 3) increases energy intake.
OBJECTIVES: To identify predictors and consequences of nutritional risk, as determined by the Mini Nutritional Assessment (MNA), in older recipients of domiciliary care services living at home.
...DESIGN: Baseline analysis of subject characteristics with low MNA scores (<24) and follow‐up of the consequences of these low scores.
SETTING: South Australia.
PARTICIPANTS: Two hundred fifty domiciliary care clients (aged 67–99, 173 women).
MEASUREMENTS: Baseline history and nutritional status were determined. Information about hospitalization was obtained at follow‐up 12 months later.
INTERVENTION: Letters suggesting nutritional intervention were sent to general practitioners of subjects not well nourished.
RESULTS: At baseline, 56.8% were well nourished, 38.4% were at risk of malnutrition, and 4.8% were malnourished (43.2% not well nourished). Independent predictors of low MNA scores (<24) were living alone, and the physical and mental component scales of the 36‐item Short Form Health Survey. Follow‐up information was obtained for 240 subjects (96%). In the ensuing year not well‐nourished subjects were more likely than well‐nourished subjects to have been admitted to the hospital (risk ratio (RR) = 1.51, 95% confidence interval (CI) = 1.07–2.14), have two or more emergency hospital admissions (RR = 2.96, 95% CI = 1.15–7.59), spend more than 4 weeks in the hospital (RR = 3.22, 95% CI = 1.29–8.07), fall (RR = 1.65, 95% CI = 1.13–2.41), and report weight loss (RR = 2.63, 95% CI = 1.67–4.15).
CONCLUSION: The MNA identified a large number of subjects with impaired nutrition who did significantly worse than well‐nourished subjects during the following year. Studies are needed to determine whether nutritional or other interventions in people with low MNA scores can improve clinical outcomes.
Healthy aging is associated with reductions in appetite and food intake--the so-called anorexia of aging, which may predispose to protein-energy malnutrition. One possible cause of the anorexia of ...aging is an increased satiating effect of cholecystokinin (CCK). To investigate the impact of aging on the satiating effects of CCK, 12 young and 12 older healthy subjects received 25-min iv infusions of saline (control) and CCK-8, 1 ng/kg per min or 3 ng/k per min, on 3 separate days before a test meal. Older subjects ate less than young subjects, and food intake was suppressed 21.6% by CCK-8, compared with the control day (P < 0.05). The suppression of energy intake by CCK-8 in older subjects was twice that in young subjects (32 +/- 6% vs. 16 +/- 6% SEM, P < 0.05) and was related to plasma CCK-8 concentrations, which were higher at baseline (P < 0.05) and increased more during CCK-8 infusions in older than young subjects (P < 0.01). The extent of suppression of food intake per given rise in plasma CCK-8 concentrations did not differ between the two age groups (P = 0.35). Endogenous CCK concentrations were higher at baseline in older subjects (P < 0.001) and decreased during the CCK-8 but not control infusions (P < 0.01), suggesting that CCK suppresses its own release. Plasma leptin concentrations were not affected by CCK infusion, whereas postprandial insulin concentrations were lowered and the peak postprandial glucose concentration was delayed but not affected by CCK-8 infusion. Because older people retain their sensitivity to the satiating effects of exogenous CCK and plasma endogenous CCK concentrations are higher in older people, increased CCK activity may contribute to the anorexia of aging.
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