Archives of Gerontology and Geriatrics
33 (2001) 243– 253
www.elsevier.com/locate/archger

Prevalence of zinc deficiency and its clinical
relevance among hospitalised elderly
Thierry Pepersack a,*, Philippe Rotsaert a, Florence Benoit b,
Dominique Willems b, Michel Fuss c, P. Bourdoux d,
Jean Duchateau e
a

Geriatic Unit, Centre Hospitalier Uni6ersitaire Brugmann, Uni6ersite Libre de Bruxelles,
´
Place Van Gehuchten 4, 1020 Brussels, Belgium
b
Chemical Laboratory, Centre Hospitalier Uni6ersitaire Brugmann, Uni6ersite Libre de Bruxelles,
´
Place Van Gehuchten 4, 1020 Brussels, Belgium
c
Department of Internal Medicine, Centre Hospitalier Uni6ersitaire Brugmann,
Uni6ersite Libre de Bruxelles, Place Van Gehuchten 4, 1020 Brussels, Belgium
´
d
Laboratory of Pediatrics, Centre Hospitalier Uni6ersitaire Brugmann, Uni6ersite Libre de Bruxelles,
´
Place Van Gehuchten 4, 1020 Brussels, Belgium
e
Laboratory of Immunology, Centre Hospitalier Uni6ersitaire Brugmann, Uni6ersite Libre de Bruxelles,
´
Place Van Gehuchten 4, 1020 Brussels, Belgium
Received 4 December 2000; received in revised form 22 June 2001; accepted 25 June 2001

Abstract
Zinc is an essential trace element, and constituent of many metallo-enzymes required for
normal metabolism. Age may be associated with altered metallothionein metabolism related
to changes in zinc metabolism. The objectives of this study were: (i) to assess the prevalence
of zinc deficiency among hospitalised elderly patients; (ii) to define the social, functional,
pathological and nutritional characteristics of zinc deficient elderly hospitalised patients; and
(iii) to assess the relationship between the zinc status and humoral immune function among
hospitalised elderly patients. Fifty consecutive patients underwent comprehensive geriatric
assessments included evaluations of the medical (index of the severity of the disease(s)),
psychiatric (Geriatric depression scale (GDS)), therapeutic, social, functional (Katz’s scale),
and nutritional problems (Mini Nutritional Assessment (MNA) and biochemical markers
(zinc, albumin, prealbumin (PAB), cholesterol) before their discharge. Fourteen patients
(28%) presented a zinc concentrations lower than 10.7 mmol/l, this value is usually considered

* Corresponding author. Tel.: + 32-2-477-2386; fax: + 32-2-477-2178.
E-mail address: thierry.pepersack@chu-brugmann.be (T. Pepersack).
0167-4943/01/$ - see front matter © 2001 Elsevier Science Ireland Ltd. All rights reserved.
PII: S 0 1 6 7 - 4 9 4 3 ( 0 1 ) 0 0 1 8 6 - 8

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T. Pepersack et al. / Arch. Gerontol. Geriatr. 33 (2001) 243–253

as the cut-off level below which a zinc deficient status is possible. Higher proportions of
respiratory infections, cardiac failure, and depression were observed among zinc deficient
patients as compared with the group of patients with normal zinc status. The other
parameters of comprehensive geriatric assessment did not allow to discriminate the zinc
deficient patients. The only slight differences (which remained unsignificant) concerned the
prealbumin levels which tended to be higher in the group of patients presenting normal zinc
status than in the group with poor zinc status (0.208 9 0.062 versus 0.171 9 0.068 g/l
respectively, P=0.06), and the IgG2 levels which tended to be lower in the group of patients
with normal zinc status than in the group presenting poor zinc status (2.77 91.91 versus
4.0692.56, respectively, P =0.057). A negative correlation was observed between the Zn
concentrations and the IgG2 levels (Spearman R = −0.311, P=0.028). To the best of our
knowledge, this is the first study presenting zinc status according to a comprehensive
geriatric assessment among European hospitalised geriatric patients. We decided to perform
this study to known whom of our patients needed to be supplemented with zinc administration. Considering the low energy intake of hospitalised patients (confirmed here in regards of
the nutritional assessment), and the insufficient trace element density in European foods, the
relevance of providing medical supplements or enriched foods to this population has to be
evaluated. Although most of the current diseases may be relevant to long-term interactions
between nutrition and ageing, certain states observed in the elderly, like impaired immune
and cognitive functions, could still benefit from an appropriate nutritional supplementation.
© 2001 Elsevier Science Ireland Ltd. All rights reserved.
Keywords: Zinc; Nutrition; Comprehensive geriatric assessment; Elderly

1. Introduction
Zinc is an essential trace element, and constituent of many metallo-enzymes
required for normal metabolism (Endre et al., 1990; Jackson and Lowe, 1992;
O’Dell, 1992). Age may be associated with altered metallothionein metabolism
related to changes in zinc metabolism (Wastney et al., 1992).
In the elderly, mild zinc deficiency may be associated with impaired cellular
immune function (Kaplan et al., 1988). Zinc supplementation is able to correct
T-lymphocyte dysfunction in zinc deficient elderly (Cossack, 1989). Several studies
in the elderly indicate that they may not cover their zinc requirement (Guigoz,
1992). Epidemiological studies suggest that people with low zinc blood levels are at
greater risk of developing diseases or conditions related to the ageing process, like
immune function impairment (Chandra, 1990), cardiovascular disease (Salonen et
al., 1982), or cancer (Strain, 1994). Zinc intake is generally reported to be
particularly low in the elderly (Gibson et al., 1985; Bunker and Clayton, 1989).
The aims of this study are: (i) to assess the prevalence of zinc deficiency among
hospitalised elderly patients; (ii) to define the social, functional, pathological and
nutritional characteristics of zinc deficient elderly hospitalised patients ; and (iv) to
assess the relationship between the zinc status and humoral immune function
among hospitalised elderly patients.

T. Pepersack et al. / Arch. Gerontol. Geriatr. 33 (2001) 243–253

245

2. Subjects and methods

2.1. Patients
Fifty patients consecutively admitted in the geriatric unit (48 beds) of our general
hospital were studied prospectively between July 15 and August 28, 1998.
All patients underwent a comprehensive geriatric assessments included evaluations of the medical, psychiatric, therapeutic, social, functional, and nutritional
problems before their discharge. These characteristics are described in Table 1 and
confirmed the ‘geriatric’ profile of the studied population (old elderly, poly-pharmacy, poly-pathology, disability, social problems, malnutrition, etc.).

2.2. Social assessment
Social evaluation included determination of age, sex, home (private versus
institution), marital status for each patient.
Table 1
Characteristics of the patients according to the comprehensive geriatric assessment (n =50)
Mean

9S.D.

83.5

6.8

Functional
Katz’scale

10.4

7.8

Medical
Greenfield
GDS
MMSE
Number of therapeutic classes

10.5
5.2
20.6
4.3

1.4
0.7
2.1
2.1

Nutritional
Zn (mmol/l)
PAB (g/l)
B.M.I.
MNA (points)

12.0
0.197
21.9
19.5

2.1
0.049
6.0
3.5

%
Social
Age (years)
Sex
Females
Males

86
14

Marital status
Widow or celibate

26

Home
Private
Institution

56
44

Social, functional, medical and nutritional characteristics of the patients (n = 50). Results are expressed
as the mean 9 S.D. or as the proportion of patients who fulfilled the condition.

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2.3. Functional e6aluation
The assessment of activities of daily living (ADL) was made using the Katz’s
scale (Katz et al., 1963). This scale involve the following items, for Katz’s scale:
bathing, dressing, transfer, toileting, continence, and eating. Each task is graded in
a four-level scale (1– 4 for Katz’s scale), lower levels represent the absence of
dependence, and upper level, the maximal dependence for the task.

2.4. Medical e6aluation
2.4.1. E6aluation of the se6erity of the diseases
The severity of the medical problems was score using a comorbidity index
adapted from Greenfield et al. (1987).
2.4.2. E6aluation of the psychiatric problems
The geriatric depression scale (GDS) was used in his French translation to assess
the probability of a depressed state (Yesavage, 1988). The scale was completed by
trained geriatricians in the presence of the patient. A score higher than five
suggested the presence of depression.
2.4.3. Cogniti6e e6aluation
Cognitive functions were assessed using the Mini Mental State Examination
(Folstein et al., 1975).
2.4.4. E6aluation of therapeutics
The number of therapies according to their classes was is collected for each
patient.
2.5. Nutritional e6aluation
2.5.1. Mini nutritional assessment
Nutritional assessment used the ‘mini nutritional assessment test’ (MNA) a
validated tool in elderly population integrated in our geriatric assessment program
(Vellas et al., 1997; Guigoz et al., 1997). The MNA test is composed of simple
measurements and of rapid questions in order to be performed in less than 10 min:
(1) anthropometric measurements; (2) dietary questionnaire; (3) global assessment;
(4) subjective assessment (self-perception of health and nutrition). The scoring of
each part allows distinguishing elderly patients with adequate nutrition to be
identified as compared with those at risk of malnutrition or who are frankly
malnourished.
2.5.2. Biochemical makers
Plasma Zinc levels were measured at 2139 nm with a Perkin– Elmer 372 atomic
absorption spectrometer according to Manning (1975). A value of zinc plasma
concentrations under 10.7 mmol/l is usually considered as the cut-off level below
which a zinc deficient status is possible (Expert Scientific Working Group, 1984).

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247

Fig. 1. Histogram of plasma Zinc values among 50 hospitalised geriatric patients.

Albumin determination was made with automated colorimetric method using
broomcresol green, prealbumin and IgG2 by by nephelometry.
Measurements of cholesterol, HDL-cholesterol and triglycerides were made by
using commercial kits. LDL-cholesterol was calculated following the formula of
Friedewald et al. (1972).
The population was divided in two groups according to their serum PAB
concentration. A serum PAB concentration higher than 170 mg/l is usually associated with a positive nitrogen balance (Mears, 1996). The patients who fulfilled
this criterion are categorised into the group that is considered presenting no risk
for proteino-caloric malnutrition (PCM). In the contrary, the group of patients
with a PAB concentration less than 170 mg/l were considered presenting a risk
of PCM.
Erytrocyte folates and vitamin B127 were evaluated by chemiluminescence
technology on immunoassay system (ACS 180 Chiron Diagnostics).
C-reactive protein (CRP) dosages were done by a turbidimetric immunoassay
(APTEC reagents).

2.6. Statistics
Data were collected in a data base using the software Access from Microsoft,
statistical analyses were performed with the software Statistica 5 Microsoft. Results from groups of patients were presented as means 9 S.D. Non parametric
Mann – Whitney test was used to compare means between the groups. Chi square
test was used to assess the differences between proportions of conditions in the
groups.

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3. Results
Fig. 1 shows the histogram of frequencies of zinc values in the whole population
(n=50). Fourteen patients (28%) presented zinc concentrations lower than 10.7
mmol/l.
Table 2 shows the characteristics of comprehensive geriatric assessment according
to zinc status. No significant changes were observed in terms of social (age, sex
ratio, marital status, home), functional (Katz), medical (co-morbidity index), and
nutritional (albumin, prealbumin, BMI, MNA) characteristics.
Table 2
Characteristics of the patients according to their plasma zinc concentrations
Zn B10.7 mmol/l (n =14)
Number (%)
Social
Age (years)
Sex
Females
Males
Marital status
Widows
Home
Private
Institution
Functional
Katz’s scale
Medical
Greenfield index
GDS
MMSE
Number of
therapeutic
classes
Nutritional
PAB (g/l)
Albumine (g/l)
Triglycerides (mg%)
CT (mg%)
HDL Chol. (mg%)
LDL Chol. (mg%)
MNA (points)
Immunology
IgG2 (g/l)

Zn \10.7 mmol/l (n =36)
Number (%)

Mean (S.D.)

84 (6)

PB

Mean (S.D.)

83 (5)

8 (57)
6 (43)

30 (83)
6 (17)

12 (86)

29 (80)

8 (57)
6 (43)

22 (61)
14 (39)
11.1 (6.9)

10.1 (4.6)

NS

12 (7)
5.6 (3.4)
20 (6)

10 (5)
5.0 (3.0)
21 (7)

NS
NS
NS

0.171 (0.068)
3.81 (0.6)
113 (39)
222 (39)
57 (13)
133 (48)
18.8 (4.8)

0.208 (0.062)
4.05 (0.6)
129 (49)
209 (49)
57 (14)
133 (33)
19.8 (4.6)

0.06
NS
NS
NS
NS
NS
NS

4.06 (2.56)

2.77 (1.91)

0.057

Social, functional, medical and nutritional characteristics of the patients (n = 50). Results are expressed
as the mean 9 S.D. or as the proportion of patients who fulfilled the condition.

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249

Fig. 2. Relationship between plasma Zn concentrations and IgG2 levels (n =50).

The only slight differences (which remained unsignificant) concerned the prealbumin levels which tended to be higher in the group of patients presenting normal zinc
status than in the group with poor zinc status (0.2089 0.062 versus 0.1719 0.068
g/l respectively, P = 0.06), and the IgG2 levels which tended to be lower in the
group of patients with normal zinc status than in the group presenting poor zinc
status (2.7791.91 versus 4.0692.56 g/l respectively, P= 0.057). A negative correlation was observed between the Zn concentrations and the IgG2 levels (Spearman
R= −0.311, P = 0.028) (Fig. 2).
If we looked at the details of the co-morbidity index, higher proportions of
congestive cardiopathy, respiratory infections, gastro-intestinal diseases and depressions were observed among the group of patients with poor zinc status as compared
to those presenting normal zinc status (Table 3).

4. Discussion
To the best of our knowledge, this is the first study presenting zinc status
according to a comprehensive geriatric assessment among European hospitalised
geriatric patients. We decided to perform this study to known whom of our patients
needed to be supplemented with zinc administration.
The evidence reviewed suggests that zinc deficiency is more frequent than
generally perceived (Stanstead, 1995). The reasons for the lack of recognition are

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several. Evaluation of the quality and quantity of dietary zinc and concurrence with
host and environmental factors that also influence zinc status is not a usual
component of clinical assessment. Thus the risk of deficiency is unappreciated.
Another problem is the insensitivity and difficulty of laboratory methods for
assessment of zinc status. Analysis of zinc in plasma, leukocytes, and other tissues
requires special instrumentation (flame atomic absorption spectroscopy). Plasma
zinc, the most commonly measured index of zinc status, is insensitive and affected
by circadian, meals, stress, and other factors that make interpretation difficult. In
addition, plasma zinc is often in the normal range unless deficiency is severe
(Stanstead, 1991). Analysis of zinc in leukocytes is difficult and not generally
available as a clinical tool.
We hoped that comprehensive geriatric assessment will allow us to discriminate
patients with zinc deficiency.
Twenty eight percent of our patients had plasma zinc concentrations B 10.7
mmol/l. This value is usually considered as the cut-off level below which a zinc
deficient status is possible (Expert Scientific Working Group, 1984). It is generally
recognised that plasma zinc concentration is not the optimal indicator of zinc
status, partly because of the influence of factors like infections or traumatic injuries
on plasma zinc levels (Gibson, 1990). Although none of the studied patients had
traumatic injuries, a significant high proportion of pulmonary infections was
Table 3
Pathological conditions of the 50 patients according to their plasma zinc concentrations
% of pathology encountered

Zn B10.7 mmol/l

Zn \10.7 mmol/l

PB

Cardiac
Arythmy
Congestive cardiopathy
High blood pressure
Peripheral vascular disease
Respiratory disease
Gastro-intestinal disorder
Liver disease
Renal disorder
Musculo-skeletal disorder
Stroke
Parkinson
Anemia
Diabetes
Tumor
Vision disorder
Audition disorder
Dementia
Delirium
Depression

64
36
21
43
43
36
50
7
21
50
14
0
21
7
0
29
21
21
0
50

53
25
0
36
33
19
31
8
28
39
22
6
31
19
8
25
25
25
6
33

ns
ns
0.001
ns
ns
0.007
0.009
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
0.05

Statistical significiance of the differences in observed proportions between the groups were assessed using
the  2 test.

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251

observed among the group of patients presenting low zinc levels as compared with
the group of patients with normal zinc concentrations. Although patients with poor
zinc status presented a (non significant) trend of high class II immunoglobulin
concentrations compared with patient with normal zinc status, this study can not
precise the relationship between zinc status and pulmonary infection.
In addition, changes in plasma zinc can be secondary to modifications in zinc
binding or to changes in the distribution of zinc among tissues. In the present case,
no significant correlation was observed between plasma zinc and albumin concentration or nutritional scores (BMI, MNA) (data not shown). The only slight
differences (which remained not significant) concerned the prealbumin levels which
tended to be higher in the group of patients presenting normal zinc status than in
the group with poor zinc status (0.20890.062 versus 0.1719 0.068 g/l respectively,
P= 0.06) suggesting that the former group tended to present a better nutritional
status.
Clinical relevance of zinc deficiency in elderly remains scant. In the zinc deficient
group, we observed a high proportion of patients presenting congestive heart failure
which are not secondary to thiamin deficiency (normal thiamin tranketolase effect),
or metabolic disease (hemochromatosis, Wilson disease). Although epidemiological
studies suggest that people with low zinc blood levels are at greater risk of
developing cardiovascular diseases (Salonen et al., 1982; Strain, 1994), further
studies are needed to confirm these data and to propose the possible underlying
mechanism(s).
Considering the low energy intake of hospitalised patients (confirmed here in
regards of the nutritional assessment), and the insufficient trace element density in
European foods (Schmuck et al., 1996), the relevance of providing medical supplements or enriched foods to this population has to be evaluated. Although most of
the current diseases may be relevant to long-term interactions between nutrition
and ageing, certain states observed in the elderly, like impaired immune and
cognitive functions, could still benefit from an appropriate nutritional supplementation. Using vitamin and mineral containing mixtures, an enhancement of certain
indices of immunocompetence was obtained in elderly subjects (Meydani, 1993;
Bogden et al., 1994; Girodon et al., 1997, 1999). Chandra (1992) reported a
decrease of infection-related illness in free-living, apparently healthy elderly people
supplemented with physiological amounts of micronutrients. However, the potential
clinical benefits of zinc supplementation in hospitalised geriatric patients remain to
be studied. Unfortunately, supplementation studies are difficult to perform in the
elderly population because of its heterogeneity, the confounding effects of inter-current diseases, and the lack of possibility to determine the patient at risk of zinc
deficiency using comprehensive geriatric assessment.
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