1. Authors
Dr Junaid Bajwa, GP Principal and Board Member of Greenwich Clinical Commissioning Group
Gwen Coleman, Registered Dietitian
Mark Lawton, Consultant Nurse, dementia care
Supported by Nutricia Advanced Medical Nutrition.
The importance
of nutrition in the
management of
early Alzheimer’s
disease
2. Introduction
Among the pledges in the NHS mandate recently announced by Health
Secretary Jeremy Hunt is a commitment to drive up diagnosis rates of
dementia.1
This builds on similar undertakings outlined in the Challenge on
Dementia initiative launched earlier in 2012.2
With hundreds of thousands of
people with dementia currently living without a proper diagnosis,3
these moves
should help improve the management of dementia and early Alzheimer’s
disease.
However, there is a danger that the drive for earlier diagnosis of Alzheimer’s
disease will amount to very little, unless it is matched by an equal commitment
to providing high-quality care to people once they are diagnosed. This care
must be holistic, person-centred and focused as much on adding life to years
as it is on adding years to life.
If there is to be a significant increase in the number of people diagnosed
while in the early stages of Alzheimer’s disease, management and personal
care plans must be formulated that not only take advantage of recent drug
developments, but also include lifestyle interventions such as exercise, mental
stimulation and nutrition.
The importance of nutrition
Good nutrition is essential for people with Alzheimer’s disease. A healthy,
well-balanced diet is essential to maintaining physical strength and good
general health. It is a valuable source of enjoyment and interaction for people
with Alzheimer’s disease and their carers, and can help those living with the
disease remain engaged and socially active, even as their cognitive abilities
begin to decline.
There is also increasing evidence that nutrition plays an important role in the
aetiology and progression of Alzheimer’s disease itself. Research suggests
certain macro and micronutrients are involved in the decline of cognitive
function and in the risk of developing Alzheimer’s disease.
Several dietary risk factors for Alzheimer’s disease have been identified,
including high intakes of saturated fat,4
raised plasma cholesterol5
and obesity.6
There is also a growing body of epidemiological evidence
suggesting certain nutrients offer protection against the condition.
There appears to be a lower risk and slower progression of Alzheimer’s
disease in people who regularly eat a ‘Mediterranean diet’ high in vegetables
and fish oils.7, 8
Diets high in omega 3 polyunsaturated fatty acids (PUFAs), vitamin E,
folate and vitamin B12 have also been linked with a reduced risk of
Alzheimer’s disease.9,10
These diets are largely in line with well-established nutritional advice for the
reduction of cardiovascular risk factors, the prevention of diabetes, obesity
and hypertension. It increasingly appears that what is good for the heart is also
good for the brain. It therefore seems sensible to include nutritional and dietary
measures as early as possible in the management of Alzheimer’s disease.
However, a number of challenges remain in the pursuit of this goal.
Nutritional intervention in
Alzheimer’s disease
Unfortunately, the early signs and symptoms of Alzheimer’s disease often
remain undiagnosed until cognitive decline is significantly advanced.
Even once a patient is diagnosed, the patient’s nutritional status is often not
considered in early disease, with no intervention being made unless there is
an obvious problem such as obesity or overt malnutrition.
The very nature of Alzheimer’s disease can also present significant barriers to
obtaining a nutritionally adequate diet. Alzheimer’s disease may be associated
with changes in taste patterns or functional difficulties that interfere with
chewing, swallowing and the preparation of food. Cognitive impairments
can make it difficult to remember or follow dietary advice. Individual social
circumstances - isolation or low income for instance - may also present
difficulties in obtaining an adequate diet. And many people with Alzheimer’s
disease suffer comorbidities, such as depression, hypertension or diabetes,
that may also impact on appetite or require difficult dietary restrictions.
Many of these challenges can be overcome by the involvement of health or
social care staff with specialist knowledge in nutritional intervention. Dietitians
or appropriately trained nursing, medical or social care staff can offer valuable
assistance in obtaining all the nutrients necessary for good general health and
optimal cognitive functioning. This is in line with the National Institute for Health
and Clinical Excellence (NICE) quality standard on dementia which states: ‘An
integrated approach to provision of services is fundamental to the delivery of
high quality care to people with dementia’.11
However, for this to happen, it is essential that health and social care staff are
sufficiently aware of the importance of nutrition in early Alzheimer’s disease and
that those with the condition receive a full nutritional assessment as early as
possible in the progress of their disease. Unfortunately, this ideal appears to
be some way removed from the reality of current practice.
Rethinking nutrition and
early Alzheimer’s disease
This report makes the case for a fundamental rethink on the position of
nutrition in early Alzheimer’s disease.
It will:
• Review the evidence on the importance of nutrition in the management
of early Alzheimer’s disease
• Discuss the ideal diet for someone in the early stages of Alzheimer’s disease
• Investigate the role that individual nutrients play in the aetiology of
the disease
• Ask how can we use this knowledge to offer people with Alzheimer’s disease
the very best nutritional support.
We will then look at current practice and the results of a survey, commissioned
for this report, of 1,006 GPs and 100 elderly care specialists involved in the
diagnosis and/or treatment of people with early Alzheimer’s disease.13
The results are discussed further later in this report; however, the findings
suggest that while most specialists recognise the importance of nutrition in
early Alzheimer’s disease, very few offer an effective and comprehensive
nutritional assessment. Only 33 per cent of elderly care specialists routinely
assess diet and nutrition during the diagnosis of early Alzheimer’s disease.
Only 22 per cent of GPs expect nutrition to be routinely assessed as part of
the diagnostic process of Alzheimer’s disease.13
Access to specialist dietetic support is both poor and under-used. Over half
of elderly care specialists and GPs in the survey were unsure of the role that
nutrition might play in the pathology of Alzheimer’s disease.
There appears to be a clear need for greater awareness about the importance
of nutrition in Alzheimer’s disease and for improved knowledge on the part that
nutritional management may play in care of the condition.
We have therefore made a number of recommendations on how current
practice could be improved.
We propose improvements to staff training and access to specialist
dietary services.
We also offer guidance on the kind of dietary and nutritional advice that could
be given to people living with Alzheimer’s disease and their carers.
1 2
CONTENTS
Introduction 1
The importance of nutrition 1
Nutritional intervention in Alzheimer’s disease 2
Rethinking nutrition and early Alzheimer’s disease 2
Nutrition in Alzheimer’s disease in practice 3
Nutrition and Alzheimer’s disease 4
Nutritional protection 4
Nutritional risk factors 4
Hearts and minds 4
How Alzheimer’s disease may affect nutrition 5
How nutrients may affect Alzheimer’s disease 5
Current practice 6
Characteristics of selected screening tools 6
Recommendations 7
Conclusion 7
References 7
There is a danger that the drive for earlier
diagnosis of Alzheimer’s disease will amount
to very little, unless it is matched by an equal
commitment to providing high-quality care to
people once they are diagnosed.
It increasingly appears that what is good for
the heart is also good for the brain.
The Patient Experience
“The thing with Alzheimer’s or dementia is that we
appear quite normal; people can’t see our problems.
If patients come into hospital it should be accepted
now that patients are assessed for their cognitive ability,
because it’s only by assessing your cognitive ability, that
you can assess if there’s something wrong with it”.12
Ann Johnson, who lives with Alzheimer’s disease
The results of our survey clearly suggest that
while the importance of good nutrition is well
recognised among specialists working with
people with Alzheimer’s disease, the role of
nutritional support is often neglected in the
management of the condition’s early stages.
3. 3 4
Nutrition and Alzheimer’s
disease
Epidemiological studies have produced a growing body of evidence to
suggest that nutrition plays a key role in the development and progression of
Alzheimer’s disease. A number of nutritional and dietary factors have been
identified that may increase the risk of Alzheimer’s disease or protect
against it.
The dietary pattern approach – our growing knowledge of how individual
nutrients affect Alzheimer’s disease has given us a valuable insight into how
these specific elements in the diet influence progression of the condition.
However, putting this information into practice is complicated by the fact that
humans rarely consume individual nutrients in isolation. Normal diets contain
complex combinations of nutrients that are likely to have a range of synergistic
effects.14
This has led to an approach known as ‘dietary pattern’ analysis, in
which nutrients are investigated in the various combinations in which they
usually occur. These ‘patterns’ or combinations appear to have a stronger
impact than the individual nutrients themselves.9
Nutritional risk factors
Raised plasma cholesterol
High serum total cholesterol has been shown to be an independent risk factor
for a number of neurodegenerative disorders including Alzheimer’s disease.5
In particular, high cholesterol has been linked with the development of the
brain plaques that are associated with Alzheimer’s disease. However, the
relationship between high cholesterol and Alzheimer’s disease appears to be
complex and trials using cholesterol-lowering drugs in Alzheimer’s disease
have, so far, proved disappointing.18
Saturated and trans fatty acids
Diets that include a high intake of saturated or trans-unsaturated
(hydrogenated) fats, found mainly in animal fats, have been shown to increase
the risk of Alzheimer’s disease. In one study of 815 people aged 65 years
or older, none of whom had Alzheimer’s disease at the outset, 131 had
developed the disease four years later.4
The researchers found that those with
the highest levels of saturated fat intake had 2.2 times the risk of developing
Alzheimer’s disease compared with those with the lowest levels. The risk also
increased with the consumption of trans fats.
Obesity
People who are obese in middle age have been shown to be twice as likely to
develop dementia compared with those of a more healthy weight.6
This study,
which followed 1,500 elderly subjects for an average of 21 years, also found
that high cholesterol and high blood pressure in midlife raised the Alzheimer’s
disease risk by up to six times.
Hearts and minds
For many years healthcare professionals have been offering dietary advice
specifically aimed at reducing cardiovascular risk factors such as obesity, high
cholesterol and hypertension. More recently it has become clear that what is
good for the heart is also good for the brain.19
A low fat, high-fibre diet with
plenty of fruit, fish and vegetables is likely to offer as much protection against
dementia as is does against cardiovascular disease.20
This is good news for
healthcare professionals who have limited time to assess their patients and
offer practical, meaningful advice. Alzheimer’s disease-focussed dietary advice
does not mean re-writing the rule book. In many cases it will mean simply
expanding on what healthcare teams should already be doing for the general
good health of their patients.
Nutritional protection
Mediterranean diet
Many of the nutrients listed below, which have been found to offer a
protective effect against Alzheimer’s disease, occur in abundance in the
typical Mediterranean diet. Diets which contain high levels of fish, fruit,
unsaturated fatty acids, vegetables rich in anti-oxidants and moderate
amounts of wine, are associated with a reduced risk and slower
progression of Alzheimer’s disease. 7, 8
Omega-3 PUFAs
It has been known for a number of years that diets high in omega-3
PUFAs may reduce Alzheimer’s disease risk. One recent study found
that a diet rich in omega-3 PUFAs, vitamin E and folate, reduced the risk
of Alzheimer’s disease by 40 per cent in those subjects who adhered
best to the diet compared with those who adhered the worst.9
Antioxidants
Antioxidants, whether obtained through the diet or in the form of vitamin
E and vitamin C supplements, have been shown to offer a measure of
protection against Alzheimer’s disease.10
It is thought that these vitamins
help protect the ageing brain from the oxidative damage associated with
pathological changes in Alzheimer’s disease.
B vitamins
It is known that inadequate intakes of B vitamins can cause a rise in
plasma homocysteine, which is a risk factor for the development of
Alzheimer’s disease.15
B vitamin supplementation has been shown to
slow brain atrophy in people with high baseline homocysteine.16
Wine
Moderate consumption of wine has been associated with a lower risk of
developing Alzheimer’s disease.17
64 per cent of elderly care specialists think that there is good evidence
linking vitamin B12 with good cognitive function.
64%
B12
In November 2012 a detailed survey13
was carried out to investigate
the practice of 100 specialists in elderly care in the UK. All of the survey
participants were involved in the diagnosis of Alzheimer’s disease and fell
into one of the following categories:
• A psychiatrist with a subspecialty in old-age psychiatry
• A geriatric medicine specialist with a subspecialty in old age psychiatry
• A general internal medicine specialist with dual accreditation in old
age psychiatry
The results showed that:
89%
Almost 9 out of 10 (89 per cent) elderly care specialists think it is
important to educate people with Alzheimer’s disease about a
healthy diet.
5 out of 10 elderly care specialists are unsure of
the role nutrition might play in the pathology of
Alzheimer’s disease (53 per cent).
83 per cent of elderly care specialists feel the importance of nutrition
in Alzheimer’s disease is to maintain general good health compared
with 6 per cent who believe nutrition has a therapeutic benefit.
83%
Only one-third of elderly
care specialists routinely
assess diet/nutrition during
the diagnostic process
for suspected Alzheimer’s
disease.
33%
1 in 5 elderly care specialists do not think diet, weight or BMI are
relevant to the diagnostic process of early Alzheimer’s disease
(22 per cent).
22%
Less than a third of
elderly care specialists
have access to a
dietitian for people
with early Alzheimer’s
disease (29 per cent).
29%
53%
Nutrition in Alzheimer’s disease in practice
Of those elderly care specialists who don’t routinely assess diet and
nutrition, 1 in 5 (20 per cent) of them have never considered nutritional
assessment, while others don’t think it is relevant.
20%
People living with Alzheimer’s disease have
been shown to have relatively low levels
of certain nutrients in their bodies despite
eating a normal diet.
4. The Patient Experience
“Marco was first worried...he kept asking me what
the day was, and what we were doing, and endlessly
repeating it, and I was getting cross, as you do, when you
don’t understand…Once we got the diagnosis,
I listened to the doctor very carefully; Marco fell asleep.
It left me feeling confused and alone and totally unsure
about what I could do to help my husband”.12
Kate Harwood – Family carer
5 6
Current practice
Nutritional assessment and screening
There are a number of clinical tools available to assess nutritional status and
screen patients for deficiencies (see Table 1). However, most of these tools
are primarily designed to identify malnutrition. Little, if any, attention is paid
to the effect of the diet on cognitive decline. Moreover, as the results of the
survey make clear, most of these tools are currently used only sparingly, or not
at all. Nutritional assessment tends to take place only when there is an obvious
problem such as malnutrition or obesity; or when the patient’s condition
has advanced to the point where they can’t prepare food, are experiencing
severely diminished appetite, or they have been admitted to hospital.
Tool Target group Tool comprises
Malnutrition Universal Screening
Tool (MUST)
Adult patients in
hospital, community and
all care settings
3 sections: BMI*, unplanned weight loss, acute disease effect; score and
management plan
Nutrition Risk Screen (NRS) Adult child hospital
patients
5 sections: BMI/percentile chart, weight loss, appetite, ability to eat/retain
food, stress factor
Subjective Global
Assessment (SGA)
Adult hospital patients 2 sections: history of: weight loss, dietary intake change,
gastro-intestinal symptoms, functional capacity, disease, physical signs of
wasting, oedema, ascites
Malnutrition Screening Tool
(MST)
Adult hospital patients 3 questions: unintentional weight loss, amount of loss, dietary
intake/appetite
Derby Nutritional Score (DNS) Adult hospital patients 7 sections: body weight for height, mobility, gastro-intestinal symptoms, skin
condition, appetite and dietary intake, psychological state, age
Mini Nutritional Assessment
Short Form (MNA SR)
Older adults 6-item initial screen: BMI, recent weight loss, mobility, cognitive/mood state,
appetite and eating. If ‘at risk’, proceed with full 18-item version
Nutritional Risk Index (NRI) Older adults 16-item questionnaire: medical history, medications, eating abilities, dietary
habits and intake, smoking, weight change
Nutritional Risk Assessment
Scale (NuRAS)
Older adults 12-item questionnaire: medical history, eating abilities, medications,
cognitive/mood state, social habits, weight loss
Characteristics of selected screening tools32
How Alzheimer’s disease
may affect nutrition
Even in the early stages of Alzheimer’s disease the symptoms of the condition can
present significant barriers to obtaining a nutritionally adequate diet.21
Alzheimer’s
disease is often associated with changes in taste patterns or, in the later stages,
functional difficulties that interfere with chewing, swallowing and the preparation of
healthy food.
Cognitive impairments can make it difficult to remember or follow dietary
advice. Individuals’ social circumstances - isolation or low income for instance
- may also present difficulties in obtaining an adequate diet.
Many people with Alzheimer’s disease suffer comorbidities, such as dental
problems, depression, hypertension or diabetes that may have their own
impact on appetite or require difficult dietary restrictions. Lack of exercise may
also lead to a loss of appetite.
Many of the nutritional challenges of Alzheimer’s disease can be overcome
by the involvement of health or social care staff with specialist knowledge in
nutritional intervention. Indeed, professional guidelines, including those from
NICE22
and the Royal College of Nursing,22
stress that care plans for people
with Alzheimer’s disease should be person-centred and include nutritional
management.
Dietitians or appropriately trained nursing, medical or social care staff can offer
valuable assistance in obtaining all the nutrients necessary for good general
health and the best possible cognitive functioning.
Phosphocholine
CDP-choline
Phosphatidylcholine
Phospholipids
Choline
Omega-3
fatty acids
B-vitamins
anti-oxidants
Uridine
Cofactors
New neuronal membrane
One of the key features of early Alzheimer’s
disease is the loss of synapses22
- the
connections within the brain that allow the
transmission of electrical or chemical signals.
Loss of synapses is associated with the loss
of memory.24
Alzheimer’s disease focussed dietary advice
does not mean re-writing the rule book.
In many cases it will mean simply expanding
on what healthcare teams should already
be doing for the general good health of
their patients.
Kennedy EP, Weiss SB. The function of cytidine coenzymes in the
biosynthesis of phospholipides. Biol Chem 1956;222:193–214.
How nutrients may affect
Alzheimer’s disease
One of the key features of early Alzheimer’s disease is the loss of synapses24
- the connections within the brain that allow the transmission of electrical or
chemical signals. Loss of synapses is associated with the loss of memory.25
Because people with Alzheimer’s disease are losing synapses more rapidly
than would otherwise be expected, they have a higher requirement to
synthesise new ones.
Synapse formation depends on a process known as the Kennedy Cycle.23
The Kennedy Cycle involves a number of nutrients as precursors (uridine,
omega-3 PUFAs and choline) and as cofactors (B-vitamins, phospholipids
and antioxidants).26
However, people living with Alzheimer’s disease have been shown to have
relatively low levels of certain nutrients in their bodies despite eating a
normal diet. Specifically:
• Low brain levels of the omega-3 PUFA docosahexanoic acid (DHA)
are associated with cognitive decline and Alzheimer’s disease27
• Plasma folate levels are reduced in Alzheimer’s disease28
• Plasma vitamin B12, vitamin C and vitamin E levels are reduced in
Alzheimer’s disease29
• Uptake of choline is reduced in the ageing brain30
• Uridine monophosphate synthesis is reduced in people with
Alzheimer’s disease.31
The biochemical pathway for
synthesising new neuronal membranes23
Table 1
* BMI = body mass index
The Kennedy Cycle
