Impact of nutrition on cognition and affectivity in the elderly: A review

Arch. Gerontol. 0167-4943/98/$19.00 IMPACT

OF

Geriatr.

suppl. 6 (1998) 459-468 0 1998 Elsevier Science Ireland

NUTRITION

ON

COGNITION

Ltd. All right

AND

reserved

AFFECTIVITY

459

IN

THE

ELDERLY:

A REVIEW

G.

SALVIOLI,

Chair of of Modena,

P.

VENTURA

Geriatrics Viale

and Vittorio

and

J.M.

Gerontology, Veneto,

9,

PRADELLI Department of I-41100 Modena,

Internal Italy

Medicine,

University

SUMMARY Preventive nutritional health care of old people is a pressing topic for physicians. In fact, malnutrition is related to impaired cognitive and affective performance in the elderly. Depression and dementia may sometimes initiate with weight loss, and selective and subclinical malnutrition (folic acid, vitamin B ) can impair cognition and affectivity. The methods for revealing cobalamin &d folic acid deficiencies need to be revised, since recommended dietary allowances and serum levels of these nutrients have not yet been established for the elderly. Homocysteine plasma concentration seems’to be an appropriate and costeffective marker of inadequate intake or bioavailability of these two vitamins, which are related to cognitive and affective performances in the elderly. In clinical practice, it is important to dispose of an instrument for adequately detecting malnutrition. One must also keep in mind that vitamin supplements may be useful in a large number of elders with psychogeriatric symptoms. Keywords:

cognitive

performance,

nutrition,

vitamin

deficiencies,

homocysteine

INTRODUCTION

ent

Nutritional

surveys

deficiencies,

an

vitamins

and

mance

and

nutrition 1994).

appetite

with

[Rolls,

fore,

depression

part

of

well

15-25

decline

and

and

cognitive

the

% in

also

with

by

failure

mood

disorders

may

of

to

depression

home

patients

poor

nutritional

be

diagnose

ranges (Alpert

and

status

subclinical

Fava,

has and

not

the to

(Rush, reduce there-

intake; screened in

the

primary

1997). been

selective

to error

in help

food

routinely

S % in

mal-

disturbances

depression from

may

prone

compromise

should

Failure

status

recall

behavioral

of perfor-

[Blumberg,

nutritional

are

nutri-

subclinical

vitamins

dietary but

and

frank deficiencies

have as

and or

intake

impairment

especially

malnutrition,

for elderly

care

Moreover,

memory

exhaustively forms,

are

clinics

studied, not

always

physicians.

Depression impairment,

rate

nursing

associated

discovered

with

1993),

such

intake

cognition

to

cognitive

seniors

diet,

diaries

alimentary

assessment.

documented:

food

minimal subclinical

composition,

healthy of

food

impaired

out and

body

apparently

utilizing inadequate

nutritional

of

components

hand,

pointed

malnutrition

compromise

history

other

have of

changes

30 % of

situations

the

elderly risk

particular

elderly On

the

influencing

About

dietary

1997).

and

mood.

Various

identify

to

minerals

regarding

elderly;

of increased

and poor to

thrive,

dementia physical

may functioning

a syndrome

initiate

with and

characterized

weight

loss.

malnutrition by

Depression, are

weight

loss,

common reduced

cognitive in

elderly appetite

as is

460 and

poor

paired

nutrition

and

immune The

cal

absence

and

,

not

observable life

for

each

since

hindered

et

The

al.,

The

mammalian

The

number

rapid

gence not

quently,

yet

well

on

cognitive

score

and

nitive

performances.

derly

changes

and

25

can

be

is

is

1995). requires

floor

height

Follow good part

the

clining

health

health may

status play

an

The

role

lopment

and

than

longevity

80

the

1969);

of

period in

functioning

and

precursors

fact, intelli-

have

metabolism

a cause

of

volumes

most

to

high

may

common

urea

with

of al.,

complex and

conse-

morbidity

greatly

fluid

in

influence

disturbance

creatinine

1990).

et

is

the cog-

in

ratio

In

the

greater

(BMI)

Lee

than

elthan

role

on

cognitive

60

% of

brain

is

in

such

is

the

as

last

it

et elderly

the

Study

stable

6

the (Wallace

low

mortality;

weight

knee of

to

Aging

seems

during

that

the

last

1992).

symptoms

of

depression

depression Indeed,

versa.

mortality

or

preceding over

Longitudinal

reciprocal;

vice

and

Paffenbarger,

between and

weight

height,

tables) the

body

with if

and

over

(kg/m2)

Baltimore

probable,

1991;

or

% of

morbidity

the

age-adjusted

weight

4-5

associated

complex

malnutrition

(using

body

other

more

al.,

of

index

inversely

interrelationships

important

loss

significant mass

are

value % of

parameters

are

are

ideal 10

a

body

the status

% of than

(Lissner

some

may

and precede

vitamins

and

depoor

minerals

functioning.

lipids up

neuronal

water

the

malnutrition;

et

and

Comprising

antioxi-

senescence.

(Winick,

cognitive

are

plasma

greater

of

changes

of

of

during

neurotransmitter

brain is

utilization

or

variations and

during

neurons

balance

and

associated

BMI

life

wide

elderly,

performances.

when

accuracy

Therefore,

heal-

protection

1994).

(Haboubi

health of

also

have

the

malnutrition

intake

on

optimum

maximal

decrease

to

Dietary

water

body

loss

the

Up.

and

of

The

and

salt

less

indicative

months ,

al.,

weight weight

months

affective

suspected

et

body

involuntary

and

in

neurons

tests

effects

Dehydration

(Weinberg A

on

in

prevent

conditions.

specific

1995).

of

elderly,

of

poorly

understood

Derangements

many

of

RDA

vary

are

help

for for

known.

vulnerable

organization

( Grantham-McGregor,

and

not

activities

particularly

children

inadequate

old

(RDA)

levels

requirements

under

metabolic is

and

malnourished

is

of

allowances

these

probably

biochemiassessment

daily

absorption

increase

and

growth

are minimum

1996).

anthropometric,

though

im-

Laths,

nutritional

and

they The

symptoms, and

for

recommended

function

brain

values

elderly,

intestinal

requirements

depressive (Sarkisian

adequate

current the

1993).

and

dehydration,

cholesterol

validated

for

capacity

vitamin

al.

has

vitamin-dependent

dant

6

serum

syndromes,

(Ames

storage

of

1994).

appropriate deficiency

thy

by

low

age-adjusted

standards

(Blumberg

probably

and of

clinical

people

accompanied

function

to

processing.

weight, Dietary

lipids fat

are

manipulation

essential in

to animals

neural affects

devesy-

461

naptosomal

membrane

expression.

Dietary

inadequate to

22:6w3

branes.

The

use

with

the

for

show

that

and

duates,

described

speed.

the

In

disease

are

lo-12

phospholipid Since

there

alimentary the

al.,

1982).

large

is

lecithin

but

be

low

of

Choline

in

for

age,

ceride

concentrations;

diac

lower

The

role

The

brain

total

represents utilizes

blood

hippocampus sufficiency,

its

also

be

reduced information

fact

it

19941,

heart

and

lipoprotein

(Muldoon

et

disease; et

is contained

in

which

tend

to

Controlling

subsets

block

al.,

dementia,

(Bartus

cholesterol on

a-

1992).

this

disease.

vocabulary [LDL)

performance

in in

benefit

Zeisel,

an

et al.,

neurons

limited

coronary

of

increased

represents

scores

in

and

None

phosphatidyl-

(Nitsch

test

lowered;

inversely

is and

show

(Canty

LDL-cholesterol

only about

Cerebral

50 % of

glucose

and

phospholipids

brain

or

be

study.

DNA

cognitive

better

contrast,

1997).

reduction

acetylcholine

density

to

al.,

men-

is assoand

design

triglyis corre-

1997).

of carbohydrates

glucose.

tracts

in

the tissue

negative

both

low

of

and

associated

et

longitudinal

total

improve

to

on and

this

choline undergra-

was

proved

(Kalmijn

controls;

may

advised

total

higher

output,

body

diets

consumption

phosphatidylcholine

of

foods

reduce

cholesterol

decline

depression

to 279

intake

in

are

intake

performance

with

with

trials

cholesterol-rich

common better

some

also task

al.,

respon-

observations

acid

degradation

of

may time

the

et

of

total

where

could

diet

risk

been in

be

Recent

serum

the

degeneration

in

may

the

mem-

ratio

(Adams

1983).

reaction

in

than

choline

fat

fish

of 2 nmolelpg

dietary

in

ciated

lated

a

or

results

amounts

% lower loss

acid

oils

increase

effects

cortex,

has

linoleic

and

(AD),

frontal

of

patients

depression

al.,

vulnerability

high

high

protective

the properties

eicosapentanoic

vegetable

E

functioning;

between Study,

whereas

and

of

relationship

impairment

depressed

et

a choice

Elderly

for

may

decline

cognitive

parietal

verage

The

synaptic

severe

[ Lieb serum

administering

showed

ethanolamine

the

1995).

Alzheimer’s

the

rate in

impairment,

antioxidants

acid-rich

depression

Zutphen

with

in

linoleic

apolipoprotein

neuronal

increases

the to

enhanced of

to

system in

arachidonic

often

a direct the

cognitive to

reduce

and

critical

nervous

changes

cholesterol

(1995),

In

related

in

Salem,

Benton

with

to is

lowering

intake.

tal

aim

rise

the

learning

are

supplement

consumption

the

[Hibbeln

in

nutritional

which

Increased

sible

a

thresholds, acids

through

of

membrane,

1996).

pain fatty

content

probably

suggested

in

acid

depression,

cell

composition, long-chain

the

main brain

with

blood and

substrate

for

vulnerable impaired

by

2 % of % of flow

oxygen

barrier is

20

is

weight, body

about

10 % of cognitive

specific to

body

total

57

the

declarative

(Kalaria damage (Craft

receives

15 % of

car-

burns

25 8 of

total

glmin, from

Glucose

transporters

memory

it and

ml/100

glucose

activity.

exocytotoxic

but

oxygen,

during et al.,

and

the

the

arterial is

and

brain blood,

transported Harik,

periods 1996).

across 1989).

of

exwith

glucose

The in-

462 The eval

importance

of

mechanisms

mances

after

levels

of

oral

brain

ticular, tasks

al.,

19941.

with

AD,

the

glucose

is marked

probably

is

synthesis

precursor

acetylcoenzyme

Glucose in

memory

with

possible

and

points be

levels

role

The

elderly

less

proteins

more

active

The

blood

The

of

seem

Rue

et

strictly

mory,

Low

also effect et

of

pletion

either

brain; such

given

utilization

in

age-related storage,

a role

in

neuro-

production

memory

in

by

of

the

as

for

improve-

the

a concomitant

after

requested

normal in

well

memory

pharmacological

conclusion,

consideration and

elderly

substrates

which In

the

verbal

biochemical

careful

serotonin,

less

or

subnor-

elderly

delayed

anemia

the

day

in

affectivity

than

due

capacity

to for

as

scores,

associated cognitive

severity;

values

in

only

not

and

are

1988). and

a longitudinal years

but

al.,

elusive

does

study

of

albumine

fact,

visceral has

cognitive

functioning. neurotransmitters influence and

the

with

impairment

of

dopamine,

In six

not

et

remains

after serum

fats snacks

(Wurtman

1993). do

intake

reflect

correlation

precursors

fewer

young

behavior

protein

and

eat

(La

follow-up levels

corwith

me-

scores.

with

most

the

and

protein-caloric

its

they

[Young,

are

also

carbohydrates

moreover,

in

memory

and

positive

declining synthesis

calories,

dietary

abstraction

reduced

dietary as

et

patients

memory

plays

declarative

1995).

serotonin

or

disease

and A

and The

to

but with

performance.

in

that of

glycolytic

and

of

people;

early

with

1993),

al.,

learning enhanced

(Gold,

concurrent

deficits,

correlate

and

a mechanisms

fewer

related

albumin

self-care

availability

transport

proteins

1997).

significantly

be

young

alert of

visuospatial

suggest

on

(Benton

glucose

regulation

par-

performance times

memory

glucose

higher in

sugar.

the

and

relate

to

achieved

consume than

al.,

studies

that

proteins

importance

not

and

promote

availability;

a deficit

transmembrane

low

list

retriperfor-

attention;

reaction

levels

of

fluency

likely

and

declarative

These

deficits;

should

reduced

correcting

seems

a word

quicker

metabolic

enhancing

suggests

may

glucose

It memory

improve

1996).

ATP

in

storage

mal

and

of

and insulin

glucose

memory

memory

of

facilitation

memory

A.

administration

ment

specific

1996).

recall

suboptimal

through

by both

better

levels

al.,

high

is effective

subjects

glucose

et

by

transmitter

as

glucose

reflect

improved

in

enhanced

(Craft may

al.,

with

attention

because

deficits

of

et

improvement

plasma

hippocampus

which

(Allen

associated

sustained

Elevated

demonstrated

enhancement

load are

requiring

memory

is

for

glucose

there

two

glucose

accounting

been

low or

and serum

between

(NT) rate

noradrenaline

of

is

synthesis formed

and

and

seems

and state

found

survival

albumin

disease

protein

reduced depression,

to

they be

inflammation and

protein

controlled from

(Katz

musculo-skeletal

visceral

of

the

within

biogenic aromatic

de-

the amines, amino

463 acids,

namely

from

tryptophan,

Factors probably

within more

Alterations

in

the

pathogenesis

the

precursor

and

in

tyrosine;

acetylcholine

is

formed

Selective

In

normal

al.,

1997).

present

in

in

availability are

al.,

involved

concentration

the

plasma et

are

1986).

are

brain

on

(Lucca

older

within

what

scores

al.,

on

are

elderly

with

cobalamin

of

required

to

1994).

In

significantly with

(Riggs

et

trations

al.,

of

vitamin

are

present

and

B,2

associated even

trations

of

though vitamin

19961.

Therefore,

vitamin

deficits The (MAT)

few

subjects

B,2

(namely

influence was

(<

plasma

of studied

acid

al.,

200

ngll)

vitamins

in

B B,2

6’ on

and

post-mortem

folic

difthe

B ,2

fo-

and

correlate

with

(Goodwin

a large in

sample

that

study

of many

deficient

higher

are

and

folic

in

(c

folic

to

of

concen-

total

homocys-

associations low

ug/l)

are concen-

(Riggs

a marker

of

et

methionine

patients

adenosyltransfewith

senile

al.,

multiple

acid). of

of

3 be

Study

lower

considered

acid

than

Aging

These

currently

score

concentration

years:

skills.

activity brains

58-81

seem

MMSE

Normative

concentrations

levels and

adequate

acid

The aged

what

the

in

with

1996).

copying

B,2

8

et

studied

tests

metabolically

those

subjects

spatial had

sometimes

are

erythrocyte

male

vitamin

area;

Rue

regards

been

attention

12

abstrac-

(La

1994).

and

homocysteine

vitamin

than

people,

folic poorer

are

Framingham

Spanish

70

with

greater the

et

functions

and

concentrations

(Ortega

examined

range

accompanied

past

have of

reasoning

et al.,

serum

results

1996)

in

vitamin

elderly

affective

Mexico

functioning

or

the

and

Herbert

New

are

in

deficiencies

normal

is

living

higher

poorer

the

the

visuospatial

concentrations

abstract

(Lindenbaum

177

and acid

serum

deficiency

acid of

folic

recall,

vitamins

by

cognitive

performances

some

cognitive

even

serum

folic

a group

those

on

of

and

on

fatigue

reported

members status

cognitive of

Insomnia, were

performances

intake

and

Americans

normal

or

best

considered

delayed

elderly

the

years,

nutritional

and

adults,

elderly. diet

66-90

the

6,2

Cobalamin

1983).

free-living

aged

vitamins but

the

acid-deficient

, 1994),

with

of

healthy

acid

teine

on

depends levels

be

and

(Young,

activities

depends

turn,

drugs

6 years;

associated

influence

In

have

in

specific

concentration,

supplements,

poorer

synthesis

tryptophan

folic

(Koehler

after

are

The

most.

degradation

availability

tryptamine

of

elderly

study

nutrient

tests

may

a 4-month

reassessed

tion

et

137

higher

ferent

normal

and

precursor

5-hydroxy its

efficacy

synthesis

of

which

malnutrition

process

by

central

plasma;

after

(1961).

were

and

NT

effect

MALNUTRITION

forgetfulness

aging

the

depression;

antidepressant

SELECTIVE

lit

of

control

than

L-tryptophan,

tryptophan

maintain

brain

peripheral

in

free

the

important

of

rase

phenylalanine

choline.

dementia;

464

IdAT “max in the

group

vides

samples

treated

evidence

chanisms

that

in

elderly

of

AD

patients

results

is

patients;

but

by

shown

the

acid

aged

OF

ELDERLY

AND

SIMPLE

not

study

in

levels al.,

matched

transmethylation

me-

different are

higher

1997).

healthy

in pro-

1996).

significantly

et

NUTRITIONAL

PATIENTS

in in

AD

subjects

healthy patients

We compared

BY

Notes:

by

t-test

Statistical

AD

evaluation

patients

had

perhomocysteinemia al.,

1993)

15 % of

as

a group

(controls).

The

mentia

as

coefficient, patients.

logistic the

a likelihood

markable

in

that

in

the

variable,

of

% based

76.2

hyperhomocysteinemia its

likely

HEALTHY

Signif.

7 3.2 12.0 0.4 52 0.6 226 1 .7 2.6 2.5

independent

p <

N.S. 0.01 0.01 0.03 0.02 0.05 0.01 0.05 0.01

samples.

serum

plasma

in

levels

than

higher

than

15

64 % of

patients

controls.

Hy-

umole/l)

(Ue-

with

dementia

controls. I,

other

groups.

regression

88 + 7 7 7 3 7 7 7 T 2

values

fasting

Table

two

patients

homocysteine

healthy in

dependent

indicating

for

BETWEEN

observations)

82 22.7 20.7 3.1 198 11.2 350 2.3 31.0 24.3

homocysteine

present

shown

different

a multiple

with

was

10 3.3 3.4 0.4 33 0.8 309 3.1 3.0 3.0

mean as

age-matched

Moreover, nificantly

higher (taken

(own

AD

60 + 7 T 7 ‘i: 7 7 T 7 T

in

AD

Controls

77 24.0 11.8 3.8 227 13.8 465 5.8 34.0 28.7

et

PARAMETERS

AFFECTED

Number of patients Age (yearsi) BMI (kg/m ) Homocysteine [ ~molell) Albumin (gldl) Transferrin (mg/dl) Hemoglobin [g/dl) Vitamin B (pglml) Folic acid’&g/ml) Calf circumference (cm) Arm circumference (cm)

in

increased

This

I.

Parameter

and

is

1996).

et al.,

homocysteine

age

patients

I

COMPARISON

land

are

(Joosten

with

AD al.,

alterations

(Morrison

levels

blood

AD

from et

with brain

patients

in Table

cortex

(Comez-Trolin

associated of

folic

affected

are

Table

and

hospitalized

frontalis B,2

regions

B,2

and in

gyrus

vitamin AD

specific

Vitamin

than

of

with

nutritional

When

analysis, we on

all

taking obtained

the

important

the

a relatively contribution

were

parameters

presence

a model

parameters

showed

parameters

of these

or

able

shown

to in

high to the

also

were absence predict

Table partial identification

sig-

entered of

de-

dementia II.

It

is

re-

correlation of

AD

465 Table

II

THE

RESULTS

OF

MULTIPLE

REGRESSION

Variables/Parameters

IN OUR

B

Folic acid Arm circumference Hyperhomocyst( Hemoglobin Albumin Notes: variable;

ANALYSIS

-

e) inemia’

B = regression dependent

SAMPLE

R

0.36 0.24 1.19 0.49 4.61

-

Signif.

0.13 0.11 0.19 0.06 0.22

coefficient, R = correlation variable: presence or absence

p <

0.03 0.04 0.01 0.04 0.01 0

coefficient; of dementia.

Categorical

CONCLUSIONS Physical begin persons

the

have

poor

health

pairs

the

.

In

overweight with

meet

two

thirds

of

nutritional

status

phagia,

also

tification al.,

taken

The

a reduction

Even

though

monstrated (Sulway

et

common subjects

in

amin

B ,2

folic

acid

account. for

Some low

elderly

have moderate

rate

cognitive 1996).

among

AD

with

impairment

patients

deficiency deficiency.

is

and of

cognitive

changes, in

the Acute

that

not

elderly; or

elderly

also

impair do

indicators

of

not poor

as

anorexia,

dys-

and

oral

or

dental

status

poor arc and

available

for

health

of

out related

the

the

problems glucose

iden(Posner

counter-re-

moreover,

the

glucose

feeding

on

prisoners

to

the

clinically

subclinical

aging in

(Goodwin and

depression

amount

et

depression is

variations

of

brain old

the

guide of

war of

important

malnutrition

functions

subacute

associated

patients

and

that

delirium

is often

per-

memory.

carried is

in

Most

impairment

noteworthy

at

such

glucose,

study

fails;

indicators

intake

and

impairment it

memory

of

im-

eating

occur

can

hypoglycemia;

learning

se

frequently

malnutrition

instruments

nutrient

a subtle

metabolic

al.,

drugs,

a

deficiencies

supplementation; minor

per

influences

anorexia

elderly.

older

precede

aging

vitamin

should

15 % of

depression

depression

Tardive

the

III;

of further

specific

concurrent

during

that

of

loss

about

Moreover,

specific

dietary

Table

enhancing

versa.

elderly.

a longitudinal

Confusion,

that

in

weight

affect;

depression

diagnosis

without

risk

of

is effective

vice

subclinical

in

into at

response

shows

RDA listed

elderly

1993).

gulatory

sons

be

of

the

involuntary and

if symptoms

and

recalled

functioning

multiple

clear or

but

the

with mood

intake,

underweight

are

fatique,

should

be

than

affective

is not

medicine

symptoms,

and

it

food

should

rather

depressive

cognitive

et

it

patient

patient’s

malnutrition,

control

geriatric

time

older

the

and

and to

the of

depression, status

same

of

assessment

ability

behaviour the

examination

with

has

weight

weight occurs

al.,

1983). symptoms symptom

mental

loss loss

in

ary

de-

of (56

status

is

elderly

vit8)

makes

of

B,2/folic

acid

more

in

amin

I3 12 homocysteine.

mical combined

are

An tained

acid levels

and

Table

III

LIST

OF

they

high

still

subclinical. knowledge

affect

levels

of

of

estimation in

of

the

aging

OF

POOR

volume of

be

to

may

nutritional the

benefits

population

be

be

by

measuring most

are

in often

prevention of (Rush,

NUTRITIONAL

is

dietary

total

et

al.,

the

pathogenesis when

needed;

it

vit-

serum bioche-

present

specific

for of

frequent

(Nilsson

implicated

indicator

procedure

the

disorders

homocysteine

is an

diagnostic

obtained

seem

psychogeriatric

deficiencies;

the

may

homocysteine

with

and

INDICATORS

indicators

of

erythrocyte

Improvement

deficiencies

patients

extended through

cognition

Major

folic

vitamin diseases.

increased

investigation.

High of

deficiencies

advisable;

clinical

and

marker

these

testing

depth

will

intervention

1996); of vitamin

be

obon

1997).

STATUS

Minor

indicators

Weight loss of more than 3 kg Anorexia Low or high BMI Poor oral/dental Serum albumin lowe than 3 gldl Dysphagia Changes in functional status Fatigue and folic acid deficiencies Multiple drug ~?e~~rBO!fslosteomalacia Mid-arm circumference below the 10th percentile Triceps skinfold below or above the 95th percentile Erythrocyte volume larger than 100 fl Plasma homocysteine above 15 umole/l

status

assumption

REFERENCES Adams, P.B., Lawson, S., Sangorski, A. and Sinclair, A.J. (1996): Arachidonit acid to eicosapentaenoic acid ratio in blood correlates positively with clinical symptoms of depression. Lipids, 31, S157-S161. Allen, J.B., Gross, A.M., Aloia, M.S. and Billingsley, C. (1996): The effects of glucose on nonmemory cognitive functioning in the elderly. Neuropsychologia, 34, 459-465. Alpert, J.E. and Fava, M. (1997): Nutrition and depression: the role of folate. Nutr. Rev., 55, 145-149. Ames, B.N., Shigenaga, M.K. and Hagen, T.M. (1993): Oxidants, anti-oxidants and the degenerative diseases of aging. Proc. Natl. Acad. Sci. USA, 90, 7915-7922. A.S. (1982): The cholinergic Bartus, R.T., Dean, R.L., Beer, B. and Lippa, hypothesis of geriatric memory dysfunction. Science, 217, 408-414. Benton, D., Owens, D.S. and Parker, P.Y. (1994): Blood glucose influences memory and attention in young adults. Neuropsychologia, 32, 595-607. Renton, D. (1995): Do low cholesterol levels slow mental processing? Psychosom. Med., 57. 50-53. Blumberg, J. (1994): Nutrient requirements of the healthy elderly; should there be specific RDAs? Nutr. Rev., 52, SlS-S18. Canty, D.J. and Zeisel, S.H. (1994): Lecithin and choline in human health and disease. Nutr. Rev., 52, 327-339.

467 Craft,

S., Newcomer, J., Kanne, S., Dagogo-Jack, S., Cryer, P., Sheline, Y Luby, J., Dagogo-Jack, A. and Alderson, A. (1996): Memory improvement following induced hyperinsulinemia in Alzheimer’s disease. Neurobiol. Aging, 17, 123-130. Gold, P.E. (1995): Role of glucose in regulating the brain and cognition. Am. J. Clin. Nutr., 61, 987S-9955. Gomez-Trolin, C., Gottfries, C.G., Regland, B. and Oreland, L. (1996): Influence of vitamin Blh on brain methionine adenosyltransferase activity in sentle dementia of t e Alzheimer’s type. J. Neural. Transm. Cen. Sect., 103, 861-872. Goodwin, J.S., Goodwin, J.M. and Carry, P.J. (1983) : Association between nutritional status and cognitive functioning in a healthy elderly population. J. Am. Med. Ass., 249, 2917-91. Grantham-McGregor, S. (1995) : A review of studies of the effect of severe malnutrition on mental development. J. Nutr., 125, 2233S-2238s. Haboubi, N.Y., Hudson, P.R. and Pathy, M.S. (1990): Measurement of heiaht in the elderly. J. Am. Geriatr. Sot:, 38, 1008-1010. Herbert, V. (1961): Experimental nutritional folate deficiencv in man. Trans. Assoc. Am. Physicians, 75, 307-320. Hibbeln, J.R. and Salem, J.R. (1995): Dietary polyunsaturated fats and depression: when cholesterol alone does not satisfy. Am. J. Clin. Nutr., 62, l-9. Joosten, E., Lesaffre, E., Riezler, R., Chekiere, V., Dereymaeker, L., PeleB mans, W. and Dejaeger, E. (1997): Is metabolic evidence for vitamin and folate deficiency more frequent in elderly patients with Alzheimer ‘4 disease? J. Gerontol. Med. Sci., 52, M76-M79. Kalaria, R.N. and Harik, S.1. (1989): Abnormalities of the glucose transporter at blood-brain barrier and in brain in Alzheimer’s disease. Prog. Clin. Biol. Res., 317, 415-421. Kalmijn, S., Feskens, E.J., Launer, L.J. and Kromhout, D. (1997): Polyunsaturated fatty acids, antioxidants and cognitive function in very old men. Am. J. Epidemiol., 145, 33-41. Katz, I.R., Beaston-Wimmer, P., Parmelee, P., Friedman, E. and Lawton, M.P. (1993): Failure to thrive in the elderly: exploration of the concept and delineation of psychiatric components. J. Ceriatr. Psychiatry Neurol., 6, 161-169. K.M. (1994): The New Mexico aging process study. Nutr. Rev., 52. Koehler, 534-537. La Rue, A., Koehler, K.M., Wayne, S.J., Chiulli, S.J., Haaland, K.Y. and Carry, P.J. (1997) : Nutritional status and cognitive functioning in a normally aging sample: a 6-y reassessment. Am. J. Clin. Nutr., 65, 20-29. I.M. and Paffenbarger, R.S. jr. (1992): Changes in body weight and Lee, longevity. J. Am. Med. Ass., 268, 2045-2049. Lieb, J., Karmali, R. and Horrobin, D. (1983) : Elevated levels of prostaglandins E and thromboxane B 2 in depression. Prostagland. Leukot. Med., 10, 3612-367. Stabler, S.P. and Allen, R.H. Lindenbaum, J., Rosenberg, I .H., Wilsen, P.W., (1994): Prevalence of cobalamin deficiency in the Framingham elderly population. Am. J. Clin. Nutr., 60, 2-11. J.c3d,! Kreger, B.E., Lissner, L., Odell, P.M., D’Agostino, R.B., Stokes, Variabillfy-of body weights Belanger, A.J. and Brownell, K.D. (1991): and health outcomes in the Framingham population. N. Engl. J . Med., 324, 1839-1844. Lucca. A., Lucini, V., Catalano, M., Alfano, M. and Smeraldi, E. (1994): Plasma tryptophan to large neutral amino acids ratio and therapeutic response to a selective serotonin uptake inhibitor. Neuropsychobiology, 29, 108-111. Morrison, L.D., Smith, D.D. and Kish, S.J. (1996) : Brain S-adenosylmethionine levels are severely increased in Alzheimer’s disease. J. Neurochem., 67, 1238-1331.

468 Matthews, K.A. and Manuck, S.6. (1997): Serum Muldoon, M.F., Ryan, C.M., cholesterol and intellectual performance. Psychosom. Med., 59, 382-387. Nilsson, K., Custafson, L., Faldt, R., Andersson, A., Brattstrom, L., Lindgren, A., Israelsson, 6. and Hultberg, B . (1996) : H yperhomocysteinemia, a common finding in a psychogeriatric population. Eur. J. Clin. Invest., 26, 853-859. Nitsch. R.M., Blusztajn, J.K., Pittas, A.G., Slack, B.E., Growdon, J .H. and Wurtman, R.J. (1992): Evidence for a membrane defect in Alzheimer disease brain. Proc. Natl. Acad. Sci. USA, 89, 1671-1675. Ortega, R.M., Manas, L. R., Andres, P., Caspar, M.J., Agudo, F. R., Jimenez, A. and Pascual, T. (1996): Functional and psychic deterioration in elderly people may be aggravated by folate deficiency. J. Nutr., 126, 1992-1999. Posner, B.M., Jette, A.M. Smith, K.W. and Miller, D.R. (1993): Nutrition and health risks in the elderly: the nutrition screening initiative. Am. J. Public Health, 83, 972-978. Rolls, B.J. (1993).: Aging and appetite. Nutr. Rev., 50, 422-426. Riggs, K.M., Spiro, A., Tucker, K. and Rush, D. (1996) : Relations of vitamin vitamin B6, folate and homocysteine to cognitive performance in the B12, Normative Aqinq Studv. Am. J. Clin. Nutr., 63, 306-314. Rush, D. (1997): Nutrition screening in old people: its place in a coherent practice of preventive health care. Ann. Rev. Nutr.. 17, 101-125. Sarkisian, C.A. and Laths, M.S. (1996): “Failure to thrive” in older adults. Ann. Intern. Med., 124, 1072-1078. Sulway, M. R., Broe, C.A., Creasey, H., Dent, O.F., Jorn, A.F., Kos, S.C. and Tennant, C.C. (1996) : Are malnutrition and stress risk factors for accelerated cognitive decline? A prisoner of war study. Neurology, 46, 650-655. Ueland, P.M., Refsum, H., Stabler, S.P., Malinow, M.R., Andersson, A. and Allen, R.H. (1993): Total homocysteine in plasma or serum: methods and clinical applications. Clin. Chem., 39, 1764-1779. Wallace. J .I., Schwartz, R.S., La Croix, A.Z., Uhlmann, R.F. and Pearlman, Involuntary weight loss in older outpatients: incidence and R.A. (1995): clinical significance. J. Am. Geriatr. Sot., 43, 329-337. Weinberg, A.D., Pals, J.K., McClinchey-Berroth, R. and Minaker, K.L. (1994): Indices of dehvdration amonq frail nursinq home patients: hiqhly variable but stable over time. J. Am.-Ceriatr. Sot;:, .1070-1673. Winick, M. [1969) : Malnutrition and brain development. J. Pediatr.. 74, 667-679. Wurtman, J .J., Lieberman, H., Tsay, R., Nader, T. and Chen, B. (1988): Calorie and nutrient intakes of elderly and young subjects measured under identical conditions. J. Gerontol. Biol. Sci., 43, 6174-8180. Young, S.N. (1986): The clinical psychopharmacology of tryptophan. In: R.J. Wurtman and J .J. Wurtman teds. I: Nutrition and the Brain, Vol. 7, pp. 49-98, Raven Press, New York. Young, S.N. (1993): The use of diet and dietary components in the study of factors controlling affect in humans: a review. J. Psychiatry Neurosci., 18, 235-244.