Changes

January 2024 — new topic. A literature search was conducted in November 2023 to identify evidence-based guidelines, UK policy, systematic reviews, and key randomized controlled trials. The evidence base has been reviewed in detail, and recommendations are clearly justified and transparently linked to the supporting evidence.

Update

Goals

To support primary healthcare professionals to:

• Identify a person with malnutrition or at risk of malnutrition by screening opportunistically or when there is clinical concern.
• Make an accurate assessment of the severity of malnutrition or risk of malnutrition, the indications for nutrition support, and manage any possible underlying cause(s).
• Refer adults with malnutrition or risk of malnutrition to a dietician for a dietary assessment and management, including advice on nutrition support and/or oral nutritional supplements (ONS) and monitoring, if clinically appropriate.
• Ensure that a person needing nutrition support receives coordinated care from a multidisciplinary team, and refer adults with malnutrition or risk of malnutrition to a speech and language therapist (SALT), occupational therapist (OT), physiotherapist, and/or other relevant specialist, depending on clinical judgement.
• Arrange ongoing monitoring in primary care, including prescription of ONS, if needed.
• Provide advice on sources of information and support for the person and/or carers.

Outcome measures

No outcome measures were found during the review of this topic.

Audit criteria

No audit criteria were found during the review of this topic.

QOF indicators

No QOF indicators were found during the review of this topic.

NICE quality standards

The NICE quality standards relevant for this CKS topic are:

• People in care settings are screened for the risk of malnutrition using a validated screening tool.
• People who are malnourished or at risk of malnutrition have a management care plan that aims to meet their complete nutritional requirements.
• All people who are screened for the risk of malnutrition have their screening results and nutrition support goals (if applicable) documented and communicated in writing within and between settings.
• People managing their own artificial nutrition support and/or their carers are trained to manage their nutrition delivery system and monitor their wellbeing.
• People receiving nutrition support are offered a review of the indications, route, risks, benefits and goals of nutrition support at planned intervals.

[NICE, 2012]

QIPP — Options for local implementation

No QIPP indicators were found during the review of this topic.

What is it?

• Malnutrition is a state in which a deficiency of nutrients such as energy, protein, and vitamins and minerals causes measurable adverse effects on body composition, function, or clinical outcome. It is both a cause and a consequence of ill health and can be caused by social factors [NICE, 2017; Malnutrition Pathway, 2021a].
• Nutrition support refers to methods to improve or maintain nutritional intake, which include [NICE, 2017]:
  • Oral nutrition support — such as fortified food, additional snacks, and/or sip feeds.
  • Enteral tube feeding — the delivery of a nutritionally complete feed directly into the gut via a tube (not covered in this CKS topic).
  • Parenteral nutrition — the delivery of nutrition intravenously (not covered in this CKS topic).
• Nutrition support should be considered in people who are malnourished, defined by any of the following [NICE, 2017]:
  • A body mass index (BMI) of less than 18.5 kg/m².
  • Unintentional weight loss greater than 10% within the last 3 to 6 months.
  • A BMI of less than 20 kg/m² and unintentional weight loss greater than 5% within the last 3 to 6 months.
• Nutrition support should be considered in people at risk of malnutrition, defined as those who have [NICE, 2017]:
  • Eaten little or nothing for more than 5 days and/or are likely to eat little or nothing for the next 5 days or longer.
  • A poor absorptive capacity and/or high nutrient losses and/or increased nutritional needs from causes such as catabolism (for example due to increased energy expenditure in chronic disease, acute illness, or surgery).

How common is it?

People with malnutrition or at risk of malnutrition are often unrecognized and untreated [BAPEN, 2012a].

• A multidisciplinary consensus document states that at any point in time, more than 3 million people in the UK are malnourished or at risk of malnutrition. It affects [Malnutrition Pathway, 2021a]:
  • 35% of people recently admitted to a care home.
  • 29% of adults admitted to hospital.
  • 30% of adults attending hospital outpatient appointments.
  • 11% of patients attending general practice.
• A British Association for Parenteral and Enteral Nutrition (BAPEN) advisory group report states that 93% of people at risk of, or affected by, malnutrition live in the community (including about 2% living in sheltered accommodation), about 5% live in care homes, and 2% are in hospital [BAPEN, 2009].
• The prevalence of malnutrition is expected to increase in the future, due to the UK's ageing population and the prevalence of malnutrition increasing with age [Elia, 2015].
  • Of the 11.6 million older people in the UK, about 1.3 million are estimated to be malnourished or at risk of malnutrition, based on annual surveys in hospitals, care homes, and the community [Malnutrition Task Force, 2021].

What are the risk factors?

The aetiology of malnutrition is complex and multifactorial. People at risk of malnutrition include those with one or more of the following [NICE, 2017] [Malnutrition Task Force, 2021] [Malnutrition Pathway, 2021a]:

• Acute illness — for example before and after surgery, acute stroke, injury, or cancer treatment, if adequate food is not consumed for more than 5 days.
• Frailty — including mobility problems, increasing age, sarcopenia, recent hospital discharge, or rehabilitation. See the CKS topic on Multimorbidity for more information.
• Appetite and eating difficulties — swallowing issues including history of surgery or radiotherapy to the upper aero-digestive tract; medications, treatments, or conditions that suppress appetite or affect taste, or cause dry mouth, nausea, or early satiety; or problems with oral health or dentures. See the CKS topics on Gastrointestinal tract (upper) cancers - recognition and referral, Head and neck cancers - recognition and referral, Parkinson's disease, Stroke and TIA for more information.
• Progressive neurological diseases such as dementia, Parkinson's disease, stroke, or motor neurone disease. See the CKS topics on Dementia, Parkinson's disease, and Stroke and TIA for more information.
• Neurodisability — such as cerebral palsy or learning disability. See the CKS topic on Learning disabilities for more information.
• Other chronic conditions including chronic obstructive pulmonary disease (COPD) or heart failure causing breathlessness and fatigue; cancer; gastrointestinal disease including inflammatory bowel disease and other causes of malabsorption or early satiety; chronic kidney disease and chronic liver disease; rheumatoid arthritis; chronic pain; and visual or other sensory impairments. See the CKS topics on Chronic kidney disease, Chronic obstructive pulmonary disease, Chronic pain, Cirrhosis, Crohn's disease, Hearing loss in adults, Heart failure - chronic, Rheumatoid arthritis, and Ulcerative colitis for more information.
• Palliative care needs. See the CKS topic on Palliative care - general issues for more information.
• Emotional and psychological — for example due to underlying anxiety, depression, and reduced motivation and energy levels. See the CKS topics on Depression and Generalized anxiety disorder for more information.
• Environmental factors — difficulty accessing or preparing food and drink that is palatable and attractive to consume, or difficulties with cooking or shopping.
• Socioeconomic factors — such as living on a low income, social isolation and loneliness, eating alone, poor mobility, being housebound, reduced social support, bereavement, or self-neglect.

What are the complications?

Malnutrition can have a negative impact on disease risk, progression, and prognosis. Possible complications or consequences of malnutrition include [Elia, 2015] [NICE, 2017] [Malnutrition Pathway, 2021a] [Dent, 2023]:

• Increased vulnerability to disease; slower recovery from illness and surgery; impaired wound healing due to less collagen deposition and impaired immune response; increased length of hospital stays; delayed rehabilitation after illness; and increased GP consultations and visits. See the CKS topics on Leg ulcer - venous and Multimorbidity for more information.
• Pressure ulcers — due to loss of skin and subcutaneous fat leading to pressure over bony prominences. See the CKS topic on Pressure ulcers for more information.
• Frailty, falls, and fractures — due to muscle weakness, reduced coordination, and osteoporosis. See the CKS topics on Falls - risk assessment, Multimorbidity, and Osteoporosis - prevention of fragility fractures for more information.
• Gradual loss of skeletal muscle mass, strength, and function (sarcopenia) with associated reduced daily functioning, loss of independence, and reduced quality of life.
• Recurrent infection, including delirium, chest infection due to loss of respiratory muscle mass and function, and skin infection due to thin, friable skin. See the CKS topics on Chest infections - adult, Delirium, and Cellulitis for more information.
• Hypothermia — due to loss of insulating subcutaneous fat and impaired thermoregulation.
• Venous thromboembolism — due to loss of muscle mass and function, and loss of energy predisposing to inactivity and immobility. See the CKS topics on Deep vein thrombosis and Pulmonary embolism for more information.
• Subfertility — due to irregular or absent menstrual cycles; reduced sperm count; or loss of libido. See the CKS topic on Infertility for more information.
• Psychological and emotional — increased rate of anxiety, depression, and cognitive impairment, which may be a central effect on the brain. See the CKS topics on Dementia, Depression, and Generalized anxiety disorder for more information.
• Self-neglect — due to reduced strength, loss of energy, apathy, and psychological impact.
• Increased mortality rates — due to both acute and chronic disease, regardless of the specific cause of death.
• Economic — malnutrition in the UK is estimated to cost in excess of £23.5 billion per year, which includes costs of increased hospital admissions and readmissions; longer hospital stays; and increased healthcare needs in the community [Malnutrition Pathway, 2021a]. This represents 15% of total expenditure on health and social care [BAPEN, 2018]. Furthermore, the overall cost of treating a person with malnutrition is estimated to be 2–3 times more than that for a well-nourished person, due to higher use of healthcare resources [Elia, 2015].

When and how should I screen a person for malnutrition or risk of malnutrition?

• Screen a person for malnutrition or risk of malnutrition opportunistically in primary care, for example at:
  • Initial registration at a general practice and then annually in the community if the person is at low risk of malnutrition.
  • Routine health checks.
  • Structured medication reviews for chronic conditions including chronic obstructive pulmonary disease (COPD) and frailty.
  • Immunisation appointments.
  • Contact with a community or district nurse.
  • Admission to a new care setting, such as a care home, and then monthly if the person is at low risk of malnutrition.
• Screen a person for malnutrition or risk of malnutrition if there is clinical concern, such as:
  • Unintentional or unplanned weight loss.
  • Apathy or fatigue. See the CKS topic on Tiredness/fatigue in adults for more information.
  • Poor appetite or early satiety.
  • Altered taste sensation.
  • Difficulty swallowing.
  • Altered bowel habits or gut function.
  • Prolonged intercurrent illness or recurrent infections.
  • Reduced physical function or frequent falls. See the CKS topics on Falls - risk assessment and Multimorbidity for more information.
  • Thin appearance.
  • Loose-fitting clothes, jewellery, or dentures.
  • Muscle wasting (sarcopenia). See the CKS topic on Multimorbidity for more information.
  • Fragile skin or poor wound healing or pressure ulcers. See the CKS topics on Leg ulcer - venous and Pressure ulcers for more information.
• Consider the use of a validated screening tool such as the Malnutrition Universal Screening Tool (MUST), using the person's body mass index (BMI), percentage of unintentional weight loss over time, and/or recent nutritional intake to score on a scale of 0–2, to determine if a person is at low, medium, or high risk of malnutrition.
  • See the section on Malnutrition Universal Screening Tool (MUST) for more information.
• If a person is identified as low or medium risk of malnutrition, arrange repeat assessment and screening depending on the person's risk factors, needs, and treatment goals.
  • See the section on Management of malnutrition for more information.

How should I assess a person with malnutrition or at risk of malnutrition?

If a person is identified as malnourished or at risk of malnutrition, assess to identify nutrition-related problems and possible underlying cause(s) of malnutrition to help guide management.

• Ask about:
  • Current and recent nutritional intake including any food, oral fluid, and/or oral nutritional supplements, over the past 5–10 days or longer.
  • The timescale over which nutrient intake has been unintentionally reduced and/or the likelihood of future impaired nutrient intake.
  • Any unintentional or unplanned weight loss including whether clothes and jewellery fit differently from usual.
  • Fluid balance and urine output to assess for dehydration.
  • Energy levels and daily activity, strength levels, and any underlying immunocompromise.
  • Any swallowing issues including difficult, painful chewing or swallowing; regurgitation of undigested food; difficulty controlling food or liquid in the mouth; drooling; hoarse voice; coughing or choking before, during, or after swallowing; globus sensation; nasal regurgitation; feeling of obstruction; or issues with oral health or dentures.
  • Any changes in eating patterns such as eating slowly, reduced oral intake, mood or cognitive changes, or avoiding social occasions, which may indicate swallowing issues or eating difficulties.
  • Any gastrointestinal symptoms such as reduced appetite, nausea, vomiting, diarrhoea, constipation, early satiety, heartburn, perceived palatability and appearance of food or drink, and/or abdominal pain or distension.
  • Any history of recurrent chest infections or atypical chest pain, which may indicate swallowing issues.
  • Any chronic neurological or neurodegenerative condition, or history of surgery or radiotherapy to the upper aero-digestive tract, which may indicate an increased risk of swallowing issues.
  • Any history of drug or alcohol misuse, which may indicate an increased risk of refeeding problems.
  • Social issues including mobility levels; financial difficulties; social isolation; or dependency on others for assistance to eat, prepare food, cook, or shop.
  • Any medication causing adverse effects on eating and drinking or interfering with nutrient absorption or metabolism; any medication causing increased risk of refeeding problems.
• Examine the person.
  • Check temperature, pulse, and blood pressure for signs of acute illness and dehydration/fluid balance.
  • Assess physical appearance including whether they look thin, signs of muscle or fat wasting, mobility and gait speed, alertness, oral hygiene including dentition and oral thrush; dry mouth or drooling; and voice quality ('wet voice' may indicate swallowing issues).
  • Assess for tongue fasciculation (may indicate motor neurone disease).
  • Assess muscle strength, for example using hand grip strength.
  • Assess weight and calculate current body mass index (BMI), and assess the trend in unintentional weight loss over the past 3–6 months.
    • Use patient-reported values of current weight, height, and previous weight if a face-to-face assessment is not possible or practical.
    • Consider using mid-upper arm circumference (MUAC) to estimate BMI if a person has severe oedema or ascites (MUAC less than 23 cm often indicates a BMI of less than 20 kg/m²).
• Consider arranging additional blood tests at baseline, depending on clinical judgement, such as:
  • Full blood count, B12, folate, and ferritin — to assess for anaemia due to folate or iron deficiency. See the CKS topics on Anaemia - B12 and folate deficiency and Anaemia - iron deficiency for more information.
  • Sodium, potassium, urea, and creatinine — to assess renal function and fluid balance. See the CKS topics on Acute kidney injury and Chronic kidney disease for more information.
  • Glucose, and liver and thyroid function tests— may reflect nutritional intake and metabolism. Glucose intolerance may occur in malnutrition.
  • Phosphate and magnesium — low levels suggest poor nutritional status and can help assess for risk of refeeding problems.
  • Calcium and albumin — hypocalcaemia may be secondary to magnesium deficiency. Low albumin reflects underlying disease process or hydration status, not protein levels.
  • C-reactive protein (CRP) — helps interpret protein, trace element, and essential vitamin results.

Management of malnutrition

From age 18 years onwards.

A literature search was conducted for guidelines, systematic reviews and randomized controlled trials on primary care management of adult malnutrition. 

Unrestricted - November 2024

Various combinations of searches were carried out. The terms listed below are the core search terms that were used for Medline.

• S3    S1 OR S2 
• S2    AB (malnutrition or undernutrition*) OR TI (malnutrition or undernutrition* ) 
• S1    (MH "malnutrition+") 

• National Institute for Health and Care Excellence (NICE)
• Scottish Intercollegiate Guidelines Network (SIGN)
• Royal College of Physicians
• Royal College of General Practitioners
• Royal College of Nursing
• NICE Evidence
• Health Protection Agency
• World Health Organization
• National Guidelines Clearinghouse
• Guidelines International Network
• TRIP database
• GAIN
• NHS Scotland National Patient Pathways
• New Zealand Guidelines Group
• Agency for Healthcare Research and Quality
• Institute for Clinical Systems Improvement
• National Health and Medical Research Council (Australia)
• Royal Australian College of General Practitioners
• British Columbia Medical Association
• Canadian Medical Association
• Alberta Medical Association
• University of Michigan Medical School
• Michigan Quality Improvement Consortium
• Singapore Ministry of Health
• National Resource for Infection Control
• Patient UK Guideline links
• UK Ambulance Service Clinical Practice Guidelines
• RefHELP NHS Lothian Referral Guidelines
• Medline (with guideline filter)
• Driver and Vehicle Licensing Agency
• NHS Health at Work(occupational health practice)

• The Cochrane Library:
  • Systematic reviews
  • Protocols
  • Database of Abstracts of Reviews of Effects
• Medline (with systematic review filter)
• EMBASE (with systematic review filter)

• NIHR Health Technology Assessment programme
• The Cochrane Library:
  • NHS Economic Evaluations
  • Health Technology Assessments
• Canadian Agency for Drugs and Technologies in Health
• International Network of Agencies for Health Technology Assessment

• The Cochrane Library:
  • Central Register of Controlled Trials
• Medline (with randomized controlled trial filter)
• EMBASE (with randomized controlled trial filter)

• Bandolier
• Drug & amp; Therapeutics Bulletin
• TRIP database
• Central Services Agency COMPASS Therapeutic Notes

• Department of Health
• Health Management Information Consortium(HMIC)

• Healthtalkonline
• BMJ - Patient Journeys
• Patient.co.uk - Patient Support Groups

The following sources are used by CKS pharmacists and are not necessarily searched by CKS information specialists for all topics. Some of these resources are not freely available and require subscriptions to access content.

• British National Formulary(BNF)
• electronic Medicines Compendium(eMC)
• European Medicines Agency(EMEA)
• LactMed
• Medicines and Healthcare products Regulatory Agency(MHRA)
• REPROTOX
• Scottish Medicines Consortium
• Stockley's Drug Interactions
• TERIS
• TOXBASE
• Micromedex
• UK Medicines Information

The external review process is an essential part of CKS topic development. Consultation with a wide range of stakeholders provides quality assurance of the topic in terms of:

• Clinical accuracy.
• Consistency with other providers of clinical knowledge for primary care.
• Accuracy of implementation of national guidance (in particular NICE guidelines).
• Usability.

• The process is inclusive and any individual may participate.
• To participate, an individual must declare whether they have any competing interests or not. If they do not declare whether or not they have competing interests, their comments will not be considered.
• Comments received after the deadline will be considered, but they may not be acted upon before the clinical topic is issued onto the website.
• Comments are accepted in any format that is convenient to the reviewer, although an electronic format is encouraged.
• External reviewers are not paid for commenting on the draft topics.
• Discussion with an individual or an organization about the CKS response to their comments is only undertaken in exceptional circumstances (at the discretion of the Clinical Editor or Editorial Steering Group).
• All reviewers are thanked and offered a letter acknowledging their contribution for the purposes of appraisal/revalidation.
• All reviewers are invited to be acknowledged on the website. All reviewers are given the opportunity to feedback about the external review process, enabling improvements to be made where appropriate.

• Key stakeholders identified by the CKS team are invited to comment on draft CKS topics. Individuals and organizations can also register an interest to feedback on a specific topic, or topics in a particular clinical area, through the Getting involved section of the Clarity Informatics website.
• Stakeholders identified from the following groups are invited to review draft topics:
  • Experts in the topic area.
  • Professional organizations and societies (for example, Royal Colleges).
  • Patient organizations, Clarity has established close links with groups such as Age UK and the Alzheimer’s Society specifically for their input into new topic development, review of current topic content and advice on relevant areas of expert knowledge.
  • Guideline development groups where the topic is an implementation of a guideline.
  • The British National Formulary team.
  • The editorial team that develop MeReC Publications.
• Reviewers are provided with clear instructions about what to review, what comments are particularly helpful, how to submit comments, and declaring interests.

Clarity Informatics has enlisted the support and involvement of patients and lay persons at all stages in the process of creating the content which include:

• Topic selection
• Scoping of topic
• Selection of clinical scenarios
• First draft internal review
• Second draft internal review
• External review
• Final draft and pre-publication

Our lay and patient involvement includes membership on the editorial steering group, contacting expert patient groups, organizations and individuals.

Scoping a literature search, and reviewing the evidence for CKS is a methodical and systematic process that is carried out by the lead clinical author for each topic. Relevant evidence is gathered in order that the clinical author can make fully informed decisions and recommendations. It is important to note that some evidence may be excluded for a variety of reasons. These reasons may be applied across all CKS topics or may be specific to a given topic.

Studies identified during literature searches are reviewed to identify the most appropriate information to author a CKS topic, ensuring any recommendations are based on the best evidence. We use the principles of the GRADE and PICOT approaches to assess the quality of published research. We use the principles of AGREE II to assess the quality of published guidelines.

• Animal studies
• Original research is not written in English

• Sample size too small or study underpowered
• Bias evident or promotional literature
• Population not relevant
• Intervention/treatment not relevant
• Outcomes not relevant
• Outcomes have no clear evidence of clinical effectiveness
• Setting not relevant
• Not relevant to UK
• Incorrect study type
• Review article
• Duplicate reference

The CKS literature searches take into consideration the following concepts, which are discussed at the initial scoping of the topic.

• Feasibility
  • Studies are selected depending on whether the intervention under investigation is available in the NHS and can be practically and safely undertaken in primary care.
• Organizational and Financial Impact Analysis
• Studies are selected and evaluated on whether the intervention under investigations may have an impact on local clinical service provision or national impact on cost for the NHS. The principles of clinical budget impact analysis are adhered to, evaluated and recorded by the author. The following factors are considered when making this assessment and analysis.
  • Eligible population
  • Current interventions
  • Likely uptake of new intervention or recommendation
  • Cost of the current or new intervention mix
  • Impact on other costs
  • Condition-related costs
  • In-direct costs and service impacts
  • Time dependencies
• Cost-effectiveness or cost-benefit analysis studies are identified where available. 

We also evaluate and include evidence from NICE accredited sources which provide economic evaluations of recommendations, such as NICE guidelines. When a recommended action may not be possible because of resource constraints, this is explicitly indicated to healthcare professionals by the wording of the CKS recommendation.

Clarity Informatics requests that all those involved in the writing and reviewing of topics, and those involved in the external review process to declare any competing interests. Signed copies are securely held by Clarity Informatics and are available on request with the permission of the individual. A copy of the declaration of interest form which participants are asked to complete annually is also available on request. A brief outline of the declarations of interest policy is described here and full details of the policy is available on the Clarity Informatics website. Declarations of interests of the authors are not routinely published, however competing interests of all those involved in the topic update or development are listed below. Competing interests include:

• Personal financial interests
• Personal family interest
• Personal non-financial interest
• Non-personal financial gain or benefit

Although particular attention is given to interests that could result in financial gains or losses for the individual, competing interests may also arise from academic competition or for political, personal, religious, and reputational reasons. An individual is not obliged to seek out knowledge of work done for, or on behalf of, the healthcare industry within the departments for which they are responsible if they would not normally expect to be informed.

Any individual (or organization) involved in developing, reviewing, or commenting on clinical content, particularly the recommendations should declare competing interests. This includes the authoring team members, expert advisers, external reviewers of draft topics, individuals providing feedback on published topics, and Editorial Steering Group members. Declarations of interest are completed annually for authoring team and editorial steering group members, and are completed at the start of the topic update and development process for external stakeholders.

None.