The chronic decrease of muscular strength affects 30% of the elderly people over the age of 60, and can go beyond 50% for the elderly people over 80 (2)

A large number of eldery do not get enough nourishment in quantity and in variety to order meet their essential energy and nutritional requirements (3). Protein and energy malnutrition is also frequent in the hospital (4).

Malnutrition limits autonomy, it decreases the quality of life while increasing the risk of bedsores, infections and hip or vertebraes fractures. Malnutrition also increases the risk of complications in case of hospitalization and it increases mortality rates. This condition alters the quality of life and increases the number of medical examinations and hospital stays (3,5-7). Malnutrition increases the costs for the elderly living at home and in institutions (2,3,7,8).

There is a physiological decrease of the muscle quotient. However, if a person carries on having a constant quantity of good quality proteins whilst ageing, there will not be any change in the person's metabolism for protein synthesis (6-14).

The nutritional risk exists when there is an insufficient nutritional intake, or an undesired weight loss > 5% in 3 months or > 10% in 6 months, or a body mass index (BMI) < 20 kg/m (7).

Malnutrition is multifactorial, favoured by :

• anxiety, apathy, tiredness and depression,
• drug intake (adverse drug reactions),
• chronic diseases,
• need of assistance for eating,
• hospital stays: acute disease, increase of metabolic needs (disease, surgery), stress due to hospitalisation,
• Alzheimer's disease and other cognitive disorders,
• deglutition disorders (following a stroke, oral surgery),
• oral and dental problems,
• minced, mixed or mashed food (15 to 26% of patients in long stay),
• rapid feeling of fullness before actually receiving necessary nourishment, and slow down of gastric drainage of liquids for elderly people (2,3,7,15,16).

It is easier to prevent than to treat malnutrition (6,10). In the case of undesired weight loss, the early intake of enriched food, or nutritional complements, increases significantly the chances of success in regards to nutrition, improvement of the autonomy and general condition (3,7).

Despite differences in the use efficiency, age does not alter the ability of synthesis of muscular proteins after the intake of protein rich food (6). It has been demonstrated that protein intake increases weight and decreases mortality (15). It is preferable to distribute the protein intake through out the day (lunch, dinner, and two snacks at 10am and 4pm) rather than offer protein rich food (meat, fish, eggs) at lunch and dinner only (2). Moreover, a recent circular precises that elderly people should not remain more than 12h without eating: it is thus recommended to give an additional snack at 9pm. (French National Food Council, notice n°53 of 15 December 2005).

 References

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2. Paddon-Jones D, Short KR, Campbell WW et al. Role of dietary protein in the sarcopenia of aging. Am J Clin Nutr 87(suppl): 2208, 1562S-6S.

3. Arvanitakis M, Beck A, Coppens P et al. Nutrition in care homes and home care: how to implement adequate strategies (report of the Brussels Forum (22-23 November 2007)). Clin Nutr 2008;27:481-488.

4. Hiesmayr M, Schnidler K, Pernicka E et al. Decrease food intake is a risk factor for mortality in hospitalised patients: the Nutrition Day Survey 2006. Clin Nutr 2009;28:484-491.

5. Milne, AC, Avenell A, Potter J. Meta-analysis: protein and energy supplementation in older people. Ann Intern Med 2006, 144:37-48.

6. Symons TB, Schultzler SE, Cock TL et al. Aging does not impair the anabolic response to a protein-rich meal. Am J Clin Nutr 2007, 86:451-456.

7. Volkert D, Bernenr YN, Cederholm T et al. ESPEN guidelines on enteral nutrition: geriatrics. Clin Nutr 2006, 25:330-360.

8. Pritchard C, Duffy S, Edington J et al. Enteral nutrition and oral nutrition supplements: a review of the economics literature. J Patenter Enteral Nutr 2006, 30:52-59.

9. Wright L, Cotter D, Hickson M et al. Comparison of energy and protein intakes of older people consuming a texture modified diet with a normal hospital diet. J Hum Nutr Dietet 2005, 18:213-219.

10. Norman K, Kirchner H, Freudenreich M et al. Three month intervention with protein and energy rich supplements improve muscle function and quality of life in malnourished patients with non-neoplastic gastrointestinal disease—A randomized controlled trial. Clin Nutr 2008, 27:48-56.

11. Campbell WW, Johnson CA, McCabe GP et al. Dietary protein requirements of youngers and older adults. Am J Clin Nutr 2008, 88:1322-1329.

12. Katsanos CS, Chinkes DL, Paddon-Jones D, et al. Whey protein ingestion in elderly persons results in greater muscle protein accrual than ingestion of its constituent essential amino acid content. Nutr Res 2008, 28:651-658.

13. Bischoff-Ferrari HA, Dawson-Hugues B, Baron JA et al. Calcium intake and high fracture risk in men and women : a meta-analysis of prospective cohort studies and randomized controlled trials. Am J Clin Nutr 2007, 86:1780-1790.

14. Borsheim E, Quynh-Uyen TB, Tissier S et al. Effect of amino acid supplementation on muscle mass, strength and physical function in elderly. Clin Nutr 2008, 27:189-195.

15. Milne AC, Potter J, Avenell A. Cochrane collaboration. Protein and energy supplementation in elderly people at risk from malnutrition (Review). The Cochrane Library Issue 1 2008.

16. Grégoire J. Prise en charge de la dénutrition en milieu hospitalier : de la théorie à la pratique. Mémoire licence professionnelle Nutrition et Alimentation Humaine. IUT Université de Montpellier. 2008.