Reducing the risks of malnutrition by ensuring adequate dietary intake

Nutritional status is crucial to a patient's state of health. Today, as people are living longer, this is becoming a major issue.

Almost two-thirds of older people in hospital are malnourished (Sullivan et al, 1999; Vellas et al, 1999). The publication of Hungry in Hospital (ACHEW, 1997) prompted the UKCC to issue a statement saying that it was the nurse's responsibility to ensure patients were adequately fed (UKCC, 1997). This paper aims to explore the issue and enable nurses to:

- Identify malnutrition

- Understand how ageing affects nutritional needs

- Understand how illness affects appetite and nutritional needs

- Understand how medication affects appetite

- Plan care to treat malnutrition

- Provide an appropriate diet for frail older people.

The nutritional needs of older people
In the early 20th century when old-age pensions were first introduced few people lived long enough to collect them. Now, as more and more people are reaching their eighties and nineties, 5000 people a year celebrate their 100th birthday (OPCS, 1993).

However, we still know little about the nutritional needs of very old people. In 1992, when the Committee on Medical Aspects of Food Policy (COMA, 1992) published its report on nutrition, it commented on the lack of data and recommended that further research was carried out.

The absence of research on the specific nutritional needs of people in their eighties and nineties means we do not know whether nutritional requirements change with increasing age, and we have to rely on studies relating to younger adults (Webb and Copeman, 1996).

For example, we do not know whether older people have the same intakes of nutrients as younger people; we do not know how common nutritional deficiencies are in older people; and we do not know whether health promotion strategies such as cutting down on dietary fat are effective or even appropriate for them.

Ageing and nutritional status
The risk of malnutrition increases with age (DoH, 1992). Malnourished people can be obese, of normal weight or thin. Many older people living at home who appear to be healthy have vitamin deficiencies (Mandal and Ray, 1987; Johnston and Thompson, 1998). Older people are most likely to suffer from deficiencies of iron, zinc and vitamin C because of prolonged illness, poor diet and malabsorption (Blee et al, 2002). Illness affects nutritional requirements as additional vitamin C is required to repair tissues. Illness can also impair ability to eat a balanced diet. People who are anaemic and have low levels of vitamin C and zinc, and are not able to repair tissues efficiently, are vulnerable to wound, chest and urine infections. Older people are particularly vulnerable to such infections due to declining immune function associated with age (Goode et al, 1991). Chandra (1992) found that, when deficiencies were corrected, infection rates were reduced among elderly people.

Older people are more likely to develop dementia, Parkinson's disease or have strokes than younger people - conditions associated with cognitive impairment, which in turn increases risk of malnutrition (Correa Leite et al, 2001).

Ageing leads to changes in the mouth and gastrointestinal tract. Older people produce less saliva, and oesophageal peristalsis is reduced, making it harder for them to chew and swallow food. Dental health has improved since the NHS was introduced, and older people today have more natural teeth than previous generations (Nazarko, 1999).

Older people who have dental problems such as cavities and broken teeth will often have problems eating and chewing (Sheiham and Steele, 2001). Those with fewer than 11 natural teeth are more likely to have difficulty eating and to be underweight (Sheiham et al, 2002).

An inadequate intake of calcium and a vitamin D deficiency will increase the risk of ill health, malnutrition, osteoporosis and fracture (Eastell and Lambert, 2002). Half an hour's winter sunlight on the hands and face will enable the body to make vitamin D to help maintain strong bones. People with dark skins require greater exposure to sunlight to manufacture vitamin D.

Frail older people are often housebound. Almost half those living in long-stay hospitals, residential and nursing homes have vitamin D and calcium deficiency because of inadequate exposure to sun (COMA, 1991).

Malnutrition in hospitals and nursing homes
Many factors influence the incidence of malnutrition in hospitals and nursing homes. These include:

- Many older people are admitted to hospital underweight and risk losing further weight in hospital (McWhirter and Pennington, 1994)

- On average, the NHS spends only £3.50 to £4 a day on food per patient in hospital (Holder, 2002). This is not a large amount. Systems such as cooked-chill have been introduced in a bid to cut costs

- Nurses no longer play a central role in serving food and helping people eat it (Green and Jackson, 2002)

- Nurses find it difficult to access food and prepare snacks for patients (Shepherd, 2002). Snacks are simply not readily available

- Many hospitals use the cooked-chill plated systems that allows food to be cooked off-site, chilled, then heated when needed. Such systems reduce vitamin C content by 45-76% (McErlain et al, 2001).

UK research indicates around 16% of people living in nursing or residential homes are malnourished (Finch et al, 1998) and two-thirds of hospital patients (Sullivan et al, 1999).

Consequences of malnutrition
Malnutrition can have serious consequences for the health of older people (Chandra, 1993; Elia, 1993; Omran and Morley, 2000; Crogan et al, 2002). For example, malnutrition can:

- Increase a person's risk of infection and affect the immune system (Box 1)

- Inhibit mobility and delay recovery

- Lead to weight loss, which results in muscle loss, affecting respiratory muscles and leading to reduced respiratory function. This makes it more difficult for people to cough and expectorate and increases the risk of chest infection

- Set up, or be part of, a vicious cycle of exhaustion, poor mobility, poor appetite and depression.

Identifying those at risk
A few simple observations and questions can help nurses identify those most at risk and carry out a full nutritional assessment. Box 2 lists some predictors of undernutrition.

If the person is undernourished or at risk of malnourishment, a full nutritional assessment should be done using an assessment tool. The Malnutrition Advisory Group (MAG) screening tool (BAPEN, 2000) covers assessment, risk calculation and management. The tool contains a table to enable nurses to calculate percentage of weight loss and body mass index.

BMI classification is shown in Table 1. However, it is important to treat BMI results with caution with regard to older people. This is because fluid disturbances such as oedema and dehydration and muscle wasting can cause the BMI to be misleading in some situations.

For example, a person who is dehydrated or has muscle wasting may appear to have a low BMI, whereas a person with oedema may not appear malnourished if staff rely solely on a BMI measurement.

The MAG screening tool consists of four processes:

- Step one: nutritional status is measured by checking height, weight and history of recent weight loss

- Step two: malnutrition risk is calculated

- Step three: this information is used to form an appropriate care plan. There are three components to the care plan. These are: setting the aims and objectives of treatment; treating any underlying conditions; and treating undernutrition. The first line of treatment for undernutrition is to provide tasty nourishing food and snacks served in a pleasant environment. Nutritional supplements are only considered if it is not possible to meet the person's nutritional requirements with food or additional food has been ineffective in treating undernutrition

- Step four is the regular monitoring and evaluation of the care plan to ensure that it continues to meet the person's needs.

Illness and nutritional status
Many conditions affect older people's ability to eat a healthy diet. Stroke can affect the fine muscle control of the tongue, jaw and lips, making chewing and swallowing difficult (Westergren et al, 2001).

Weakness or paralysis in the limbs can make it difficult to cut up food and eat it. Arthritis may make it difficult for a person not only to cut up food but also to lift cutlery.

Visual problems such as macular degeneration, cataracts and glaucoma make it difficult for someone to see food and to eat delicately. Often older people are so embarrassed by eating difficulties that they prefer to go hungry. People with dementia may be unable to recognise food or to eat independently (Drewnowski and Shultz, 2001; Nazarko, 2002).

Medication and nutrition
Many prescribed medicines can affect appetite: for example, the use of antidepressants may increase appetite, resulting in weight gain (Vanina et al, 2002). The patient taking the medication will often begin to eat properly because they feel better, and this improved nutrition leads to an increased sense of well-being.

Drugs used to treat Type 2 diabetes can increase or suppress appetite. One group of oral hypoglycaemic drugs, known as biguanides (such as metformin) suppress appetite and can help overweight diabetes patients lose weight (Knowler et al, 2002).

Another group of oral hypoglycaemics are the sulphonylureas (such as glibenclamide and gliclazide): these increase appetite and can help underweight people with diabetes gain weight (Groop, 1997).

Anticholinergic drugs given to treat bowel spasm or urge incontinence can cause a dry mouth and this can reduce appetite (Hay-Smith et al, 2002).

Some medications can impair the absorption of vitamins and nutrients, leading to nutritional deficiencies. Antacids reduce the absorption of dietary iron and iron tablets. Vitamin C can be given to counteract this, and giving a glass of orange juice with an iron tablet will increase absorption.

Corticosteroids given long term increase the excretion of vitamin C. Corticosteroids also lead to reduced protein absorption and loss of muscle and bone (Walsh et al, 2002).

Phenytoin reduces the absorption of vitamin D and folic acid. People on long-term phenytoin benefit from calcium and vitamin D supplements to prevent bone loss, and folic acid to prevent pernicious anaemia.

Sedatives and night sedation can lead to daytime drowsiness in older people and therefore reduced food intake.

Reducing malnutrition risk
Nurses in NHS settings have little influence over the way food is prepared and served. It is often prepared off-site and is not tailored to the needs of frail older people. But NHS nurses can work with catering staff to improve the diets of older people (Kydd, 2002).

Those working in care homes have an easier task when it comes to ensuring older people receive appropriate diets. Homes cater for fairly small numbers of people and the home manager employs the chef directly.

Nurses in all care settings can draw on research to reduce the risks of malnutrition (Table 2). Offering a varied diet is essential. People who can only choose from a narrow range of foods are more likely to be malnourished than those who have more choice (Bernstein et al, 2002).

Many older people have difficulty chewing and swallowing because of age-related changes and the effects of illness and medication. Food should not be too dry or difficult to chew; adding sauces and gravies can make food easier to eat. Ice-cream, cream and custard can make fruit pies and cakes more manageable. There should be a range of different textured food at each meal, so the person may have a normal, soft or puréed diet as required.

Not all older people have the same energy requirements. Men need more calories than women and people with wounds require a higher calorie intake to enable them to repair tissues (COMA, 1992; Sullivan et al, 1999).

Snacks - People living at home and independent people in hospital can eat snacks, which provide extra calories and nutrition. Offering snacks between meals reduces the risk of undernutrition. Relatives can help build up the frail older person with chocolate - a rich source of iron - cream cakes and other high-density foods.

Dependency - Older people who eat independently are less likely to be malnourished that those who depend on nursing staff to feed them. Their nutritional status can be aided by providing plates with deep rims, non-slip mats, and other ways to encourage and enable them to eat independently.

In hospital and community settings occupational therapists play an important role in assessing people and providing appropriate aids and adaptations to enable independent eating. In care homes, however, it is very difficult to obtain occupational therapy advice.

People enjoy eating when they are in a conducive atmosphere. Nurses can help make mealtimes a pleasure by ensuring patients are not disturbed by the medication round or other unnecessary interruptions, and ensuring staff are available to help residents eat. Mealtimes should be pleasant and unrushed. Food should be presented attractively to people with poor appetites. It should be freshly cooked and look appealing. Only a very hungry person would relish a meal of cauliflower, mashed potatoes and white fish, for example.

An enriched diet will help correct nutritional deficiencies. Ageing affects appetite, and providing meals rich in nutrients and energy will reduce the risk of malnutrition. The challenge for chefs is to pack as many nutrients and calories as possible into small portions.

Conclusion
Nurses have an important role in assisting frail older people at risk of malnutrition. By enabling older people to eat a healthy diet they can enhance their quality of life and help protect them against illness and disease.

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