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Pathy's Principles and Practice of Geriatric Medicine. Группа авторов
Читать онлайн.Название Pathy's Principles and Practice of Geriatric Medicine
Год выпуска 0
isbn 9781119484295
Автор произведения Группа авторов
Жанр Медицина
Издательство John Wiley & Sons Limited
The use of the Mini‐Nutritional Assessment (MNA) to explore weight loss
The evaluation of unintended weight loss begins with identifying people at risk. Several assessment instruments have proven validity in the assessment of weight loss or subsequent mortality. The Mini‐Nutritional Assessment (MNA) was developed to assess malnutrition in elderly populations. The full MNA is a multidimensional tool that identifies malnourished older subjects or those at risk for malnutrition, whatever the cause.63 A shorter form has been developed with similar performance64 (Figure 14.2). The MNA assesses body mass with either BMI or calf circumference.
Subjects with a normal baseline score had a lower mortality risk (0.35; 95% CI 0.18–0.66) than subjects with an abnormal MNA score. Subjects judged to be at risk for undernutrition by the MNA had more frequent acute illness, need for more assistance, and more weight loss. The MNA was found to be 96% sensitive and 60% specific for body weight loss. A subsequent analysis found that a six‐item version of the MNA has equivalent predictive value.
The MNA can be used to assess cancer cachexia.65 MNA is a powerful prognostic factor for several pathologies, particularly in cancer.55,66
Interventions
The treatment of undernutrition in the elderly begins with a careful differential diagnostic approach aimed at finding reversible medical causes. Medical conditions that may be associated with anorexia, decreased food intake, or increased metabolic requirements should be assessed. Anorexia may be associated with illness, drugs, dementia, or mood disorders. Decreased food intake may result from dysphagia, chewing problems, nausea, vomiting, diarrhoea, pain, or faecal impaction. Increased metabolic requirements may be precipitated by fever, infection, or the presence of chronic skin wounds. Treatment of these conditions may restore appetite and body weight.
Comprehensive gerontological assessment (CGA; see Table 14.3) is therefore a helpful tool for care in complex situations: multiple comorbid conditions or frailty. Starvation and cachexia are frequently associated, and simple interventions such as oral care can improve nutritional status and quality of life. Furthermore, CGA enables providing integrative care, including treatment optimization, assessment of food intake capacities, and improvement in function.
Decreased food intake
The first response of caregivers to weight loss, whether due to starvation or to cachexia, is to increase nutrient intake. Decreased incidence of pressure ulcers during hospital stays was shown with oral supplementation.67 In a meta‐analysis of 42 trials, nutritional supplementation produced a mean difference in weight gain of 2.3%. Reduced mortality was observed in the supplemented compared with control groups (relative risk [RR] = 0.74; 95% CI 0.59–0.92) in 32 trials. The subgroup analyses suggested that the effects on mortality were consistently significant when limited to trials in which participants were defined as undernourished (RR = 0.72; 95% CI 0.55–0.94), when 400 kcal or more was offered per day in the supplement (RR = 0.71; 95% CI 0.56–0.90), when participants were at least 75 years old (RR = 0.69; 95% CI 0.54–0.87), when supplementation was continued for 35 days or more (RR = 0.75; 95% CI 0.56–1.00), when participants were unwell (RR = 0.73; 95% CI 0.59–0.92), and when participants were in the hospital or a nursing home (RR = 0.67; 95% CI 0.52–0.86). However, there was no evidence of improved functional status or reduction in length of hospital stays with supplements.68 Nutritional advice given to older patients at risk for malnutrition during the chemotherapy period increased energy and protein intake as compared to routine care but did not modify mortality or quality of life.54,69 In older patients treated for cancer, a nutritional care plan integrated with global geriatric care is recommended.70
In nursing homes or long‐term care homes, nutritional support should be organized both at the resident level and at the institutional level.71,72
A failure to consume adequate nutrients or supplements often leads to enteral feeding. Enteral feeding can frequently be life‐saving, but improving nutritional parameters is difficult to verify.73 There is little evidence for benefit in survival or comfort for enterally fed patients with weight loss due to cancer cachexia, and there are substantial associated risks, discomforts, and costs.74 Enteral feeding in nursing home residents older than 65 with severe cognitive impairment did not affect survival at 24 months compared with residents who were not enterally fed.75 In nursing homes, only long‐term percutaneous enteral feeding was associated with increased survival. Adverse events such as aspiration pneumonia occurred at a similar rate with or without enteral feeding.76 The results of percutaneous parenteral feeding in subacute patients was not optimal.77 Survival in other medical conditions does not appear to be affected by enteral feeding. A downward trend in the use of parenteral nutrition in critical care patients has occurred over the last few years, chiefly due to studies showing higher morbidity with parenteral nutrition compared with enteral nutrition.78
Undernourished or high‐risk surgical patients did not have postoperative complications reduced to that of well‐nourished patients undergoing similar procedures by enteral or parenteral support.79 These data suggest that factors other than pure starvation are operational since a response to refeeding is the hallmark of starvation.
The effect of exercise to improve body mass and function
For people with sarcopenia, the primary intervention should include resistance exercise interventions. The increase in muscle protein mass is attributable to an acute and chronic increase in muscle protein turnover, resulting in the rate of muscle protein synthesis exceeding that of muscle proteolysis. Coincident with the increase in the amount of muscle protein are increases in maximum voluntary muscle strength and muscle fibre hypertrophy.80 Progressive resistance training two or three times per week improves physical function and reduces physical disability and muscle weakness in older adults. Functional limitations such as balance, gait speed, timed walk, timed get up and go, chair rise, and climbing stairs also improve.81 The improvement in muscle mass and strength with resistance exercise extends even to the very old. However, little is known about the duration of these effects once training has stopped.
Figure 14.2 Mini‐Nutritional Assessment (MNA).
.Source: Nestle Nutrition Institute, Mini Nutritional Assessment. © 2020, Nestle Nutrition Institute. © Société des Produits Nestlé SA 1994, Revision 2009. MNA® website for further information: www.mna‐elderly.com.
Table 14.3 Comprehensive gerontological assessment (CGA) to address weight loss management.
| Domain | Subdomain | Proposed screening tools | Action if impaired | Link to other subdomains and nutrition |
|---|---|---|---|---|
| Mental health | ||||
| Cognition |