Journal of Aging Research & Clinical Practice©
Volume 2, Number 2, 2013
NUTRITIONAL STATUS BUT NOT VITAMIN DEFICIENCIES
ARE ASSOCIATED WITH LOW FUNCTIONAL SCORES
F. O’Leary
1
, M. Allman-Farinelli
1
, P. Petocz
2
, S. Samman
1
Introduction
Geriatric rehabilitation patients are at high risk of
malnutrition (1-3), muscle wasting and difficulties with
activities of daily living (3-5). Undernourished geriatric
hospital patients have poor function on admission (3, 4, 6,
7), increased functional decline (4, 6, 7), delayed
functional recovery (3) and require greater support (3, 5).
One of the most widely used functional assessment tools
is the Functional Independence Measure (FIM) (8).
Undernutrition is related to inadequate energy and
vitamin intake and can result in subclinical deficiencies
(1). Deficiencies of B vitamins may affect cellular and
disease processes (9), with vitamins B12 and folate
essential for one-carbon metabolism, DNA methylation
and nucleotide synthesis. Low vitamin B12 status is
linked to mitochondrial dysfunction and inflammation (9,
10). Frailty and disability are associated with poor B
vitamin status (11) and hyperhomocysteinaemia, a
marker of inadequate status is linked to poorer physical
function (12). Vitamin D is required for cellular growth
and for central nervous system and muscle function (13).
Little, however, is known of effects of subclinical vitamin
deficiencies and whether specific nutrient inadequacies
affect function and health.
This study explores the relationship between the
selected nutrients, vitamins D, B12 and folate, nutritional
status and the functional capacity of elderly rehabilitation
patients as measured by FIM.
Methods
The study was conducted in a 48 bed sub-acute
geriatric rehabilitation unit. Newly admitted subjects
were recruited in 2, six week periods in August and
September of 2005 and 2006.
Patients with inadequate English or diagnosed
dementia without a carer were excluded. The study
protocol was approved by the Calvary Health Care
Sydney Ethics Committee, and patients or caregivers
provided consent. Potential confounders assessed
included medical history, cognitive status, serum
albumin, creatinine and urea. Subjects who returned to
an acute hospital or those with missing FIM data were
removed from analysis. The Charlson co-morbidity index
was calculated (14).
1. Discipline of Nutrition and Metabolism, School of Molecular Bioscience,
University of Sydney, NSW 2006, Australia; 2. Department of Statistics, Macquarie
University, NSW 2109 Australia.
Corresponding Author: Samir Samman PhD, Discipline of Nutrition and
Metabolism, School of Molecular Bioscience, G08, University of Sydney, NSW
2006 Australia, Fax: 9351 6022, Ph: 9351-2476, email: samir.samman@sydney.edu.au
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Abstract: Objectives: To investigate relationships between selected vitamins, nutritional status and functional outcomes. Design:
Cross-sectional study. Setting: Sub-acute geriatric rehabilitation hospital. Participants: 146 newly admitted rehabilitation patients.
Measurements: Nutritional assessment using the Mini Nutritional Assessment (MNA) tool, vitamins B12, D and folate
concentrations. Length of stay and Functional Independence Measure data were collected from discharge medical records. Results:
Age was 83 ± 7 (mean ± sd) years and BMI 25 ± 6 kg/m
2
. The majority (80%) of subjects were malnourished or at risk of
malnutrition and 20% of them had 2 or more vitamin concentrations below the reference range. Vitamin D < 50 nmol/L was found
in 55%, vitamin B12 < 221 pmol/L in 34% and serum folate < 6.8 nmol/L in 6% of subjects. Function was related to nutritional
status determined by the MNA tool but not related to vitamin concentrations. The assessment component of the MNA score
predicted 10% of admission function (β = 0.36, p<0.0005), and subjects with poorer functional scores (< 95) had lower mean MNA
scores (19 versus 21, p=0.028). Conclusion: Nutritional status was associated with low functional scores. Low concentrations of
vitamins D and B12 were common but were not related to function. More research is needed to investigate the relationship between
nutritional status and function.
Key words: Nutrition assessment, avitaminosis, activities of daily living, rehabilitation assessment, geriatric assessment.
Received November 21, 2012
Accepted for publication January 4, 2013
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