Norfolk Learning Disability Service
Room 026 County Hall
Martineau Lane
Norwich
NR1 2DH
Telephone No: 01603 638533
Mobile No: 07796940507
Fax No: 01603 638521
Email:
Website:
Nutrition Screening and People with a Learning Disability
The Malnutrition Universal Screening Tool (MUST) is a validated nutrition screening tool and is widely used particularly amongst the elderly population. It is not however promoted as a tool to be used with people with a learning disability.
MUST has a heavy reliance on Body Mass Index (BMI). BMI needs to be used with caution in some situations:
- Where people have an altered body composition, such as people who are non- weight bearing, BMI will be lower than standard reference ranges. A normal BMI may never be reached. It would also be inappropriate as all weight gained would be central due to immobility, which therefore has health implications. By following MUST guidance inappropriate dietary intake may be provided
- BMI has not been validated for heights less than 1.47m
- Calculation of BMI includes measuring height. It is more difficult to measure height in people with physical anomalies. The use of surrogate measures of height e.g. ulna length, knee height and supine length have all been found to not give accurate results and BMI would be unable to be calculated accurately
- Mid upper arm circumference (MUAC) can also be used to calculate BMI. However this is also not likely to give accurate results. Individuals may have upper limb muscle contractures, the non-dominant arm may not be apparent, physical anomalies may mean the bony reference points are difficult to locate and the procedure may be distressing. Standard reference tables are based on an average American population who have a different body composition and stature to people with a learning disability and physical impairments
Other frequent nutritional risk factors for people with a learning disability include a higher incidence of overweight and obesity than the general population. Limited and rigid intake of foods leading to a poorly balanced diet which doesn’t meet nutritional requirementsis also common. There may not be unplanned weight loss and if BMI can be used it may be within the desirable range. In these situations MUST is unlikely to identify the nutritional risk these individuals have.
MUST was not validated with people with a learning disability and there is currently no validated nutrition screening tool for people with a learning disability. Locally tools have been developed using clinical knowledge and expertise. These tools are available on request.
Alison Clark RD
Specialist Dietitian Learning Disability
18.03.15