Porvoo sarcopenia and nutrition trial: Effects of protein supplementation on functional performance in home-dwelling sarcopenic older people - study protocol for a randomized controlled trial

Abstract

Background:
Age-related muscle loss (that is, sarcopenia) is a common health problem among older people. Physical exercise and dietary protein have been emphasized in prevention and treatment of sarcopenia. Rigorous trials investigating the effects of protein supplementation on physical performance in sarcopenic populations are still scarce. The aim of this study is to investigate the effects of protein supplementation along with simple home-based exercises on physical performance among home-dwelling sarcopenic older people.

Methods/design:
During 2012 the entire 75 and older population (N = 3,275) living in Porvoo, Finland was contacted via a postal questionnaire. Persons at risk of sarcopenia are screened with hand grip strength and gait speed. Poorly performing persons are further examined by segmental bioimpendance spectroscopy to determine their skeletal muscle index. Sarcopenic patients (target N = 250) will be enrolled in a 12-month randomized controlled trial with three arms: 1) no supplementation, 2) protein supplementation (20 grams twice a day), and 3) isocaloric placebo. All the participants will receive instructions on simple home-based exercises, dietary protein, and vitamin D supplementation (20 μg/d). The recruitment of patients will be completed during 2013. The primary endpoint of the trial is the change in short physical performance battery score and percentage of patients maintaining or improving their physical performance. Secondary endpoints will be, among other things, changes in muscle functions, nutritional status, body composition, cognition, quality of life, use of health care services, falls, and mortality. The assessment times will be 0, 6, 12 and 24 months.

Discussion:
To our knowledge, this is the first large scale randomized controlled trial among community dwelling older people with sarcopenia that focuses on the effects of protein supplementation on physical performance.

Trial registration:
ACTRN12612001253897, date of registration 28 October 2012, first patient was randomized 11 April 2012.

Full text

S T U D Y P R O T O C O L Open Access
Porvoo sarcopenia and nutrition trial: effects of
protein supplementation on functional
performance in home-dwelling sarcopenic older
people - study protocol for a randomized
controlled trial
Mikko P Bjorkman
1*
, Merja H Suominen
2
, Kaisu H Pitkälä
3
, Harriet U Finne-Soveri
4
and Reijo S Tilvis
1
Abstract
Background: Age-related muscle loss (that is, sarcopenia) is a common health problem among older people.
Physical exercise and dietary protein have been emphasized in prevention and treatment of sarcopenia. Rigorous
trials investigating the effects of protein supplementation on physical performance in sarcopenic populations are
still scarce. The aim of this study is to investigate the effects of protein supplementation along with simple
home-based exercises on physical performance among home-dwelling sarcopenic older people.
Methods/Design: During 2012 the entire 75 and older population (N = 3,275) living in Porvoo, Finland was
contacted via a postal questionnaire. Persons at risk of sarcopenia are screened with hand grip strength and gait
speed. Poorly performing persons are further examined by segmental bioimpendance spectroscopy to determine
their skeletal muscle index. Sarcopenic patients (target N = 250) will be enrolled in a 12-month randomized
controlled trial with three arms: 1) no supplementation, 2) protein supplementation (20 grams twice a day), and 3)
isocaloric placebo. All the participants will receive instructions on simple home-based exercises, dietary protein, and
vitamin D supplementation (20 μg/d). The recruitment of patients will be completed during 2013. The primary
endpoint of the trial is the change in short physical performance battery score and percentage of patients
maintaining or improving their physical performance. Secondary endpoints will be, among other things, changes in
muscle functions, nutritional status, body composition, cognition, quality of life, use of health care services, falls, and
mortality. The assessment times will be 0, 6, 12 and 24 months.
Discussion: To our knowledge, this is the first large scale randomized controlled trial among community dwelling
older people with sarcopenia that focuses on the effects of protein supplementation on physical performance.
Trial registration: ACTRN12612001253897, date of registration 28 October 2012, first patient was randomized 11
April 2012.
Keywords: Sarcopenia, Frailty, Cachexia, Older people, Community-dwelling, Randomized controlled trial
* Correspondence: mikko.bjorkman@helsinki.fi
1
Geriatric Unit, Department of Internal Medicine, University of Helsinki, PO
Box 340, 00029 HUS Helsinki, Finland
Full list of author information is available at the end of the article
TRIALS
© 2013 Bjorkman et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.
Bjorkman et al. Trials 2013, 14:387
http://www.trialsjournal.com/content/14/1/387

Background
Age-related muscle loss (that is, sarcopenia, a syndrome
characterized by progressive and generalized loss of skeletal
muscle mass and strength [1,2]) is closely related to mal-
nutrition, physical inactivity, inflammation, and cachexia
(disease-related muscle loss) [3], which all are hallmarks
of frailty [4]. All these conditions are associated with a risk
of adverse outcomes (for example, physical disability, poor
quality of life, and increased risk of morbidity and mortality
[1-4]). According to the European consensus, sarcopenia is
defined as low fat-free mass related to squared height
in combination with low muscle strength or slow gait
speed [1]. However, there has been practical difficulties
in assessing muscle mass and, thus, diagnosing sarcopenia
[2]. Several methods are available for the measurement of
fat-free mass. These methods include magnetic resonance
imaging, computer tomography, dual x-ray absorptiometry
(DEXA), and bioimpedance analysis (BIA). The validity
of conventional BIA measurements has been questioned,
but recent evidence on direct segmental multifrequency
measurements (DSM-BIA) has shown good accuracy in
comparison with DEXA [5]. The fully portable BIA devices
also allow the assessment of disabled older persons during
home visits. Furthermore, changes in segmental intracel-
lular resistance measured by bioimpedance spectroscopy
(BIS), an extension of DSM-BIA, has been shown to be as-
sociated with changes in mobility in typical nursing home
residents prone to sarcopenia, frailty, and cachexia [6].
Even though the mechanisms of sarcopenia are complex,
adequate physical activity and nutrition are important
for the maintenance of muscle functions in older people
[1]. The broad health benefits of resistance exercise in
older people are relatively well documented [7]. However,
the lack of transportation services for the disabled patients
to the exercise facilities and the lack of human resources
often limit the large scale use of these regimens in clinical
practice. Evidence from intervention studies shows
that nutritional supplementation of older people at risk
of malnutrition increases their body weight and seems
to decrease the risk of death [8]. Furthermore, in addition
to physical exercise, the role of dietary proteins and vitamin
D has been emphasized in the prevention and treatment of
sarcopenia and frailty [9-14]. According to a 2013 sys-
tematic review, nutritional supplementation is effective
in improving muscle mass and to some extent muscle
strength as well in old age [15]. However, long-term
evidence on the effects on physical performance from
representative sarcopenic populations of older people
is scarce [13,14].
The aim of this randomized controlled trial is to investi-
gate whether and to what extent protein supplementation
and simple home-based exercises are able to maintain
physical performance in community dwelling older people
with sarcopenia. In addition, we will examine the effects
of the intervention on different aspects of muscle health,
quality of life, use of health-care services and mortality.
Methods/Design
General design
This study is a randomized controlled trial in which the
community dwelling older people with sarcopenia living
in Porvoo, Finland, are randomly allocated into three arms:
1) no supplementation, 2) protein supplementation, and
3) isocaloric placebo. In addition, all the participants will
receive instructions on simple home-based exercises,
importance of dietary protein, and the use of vitamin D
supplementation with the dose of 20 μg/d. The interven-
tion will last for 12 months. The study has been approved
by the Ethics Committee of the Helsinki University Central
Hospital. Informed consent will be obtained from each
patient or if necessary from their closest proxy before
any study procedures, which will be performed according
to good clinical practice [16].
Participants
A postal questionnaire was sent in 2012 to all people aged
75 years and older living in Porvoo, Finland (N = 3,275).
The persons at risk of sarcopenia (limitations in activities
of daily living, low physical activity, falls, exhaustion, high
age, or low body mass index (BMI)) will be contacted by
telephone, and those interested in further examinations will
be screened by hand grip strength [17] and habitual gait
speed [18]. Persons with low hand grip or slow habitual gait
speed and low skeletal muscle index (SMI) measured by
segmental calf BIS [6,19] will be recruited one by one, with
researchers approaching them or their closest proxy.
Inclusion criteria and exclusion of participants:
1. 75 years or older, living permanently at home in
Porvoo, Finland
2. able to walk indoors independently (canes and
walkers allowed)
3. able to co-operate with hand grip, walking speed,
and BIS measurements
4. lowhandgripstrength(men≤30.0 kg, women ≤20.0 kg)
or slow habitual gait speed (≤0.80 m/s)
5. low SMI (2 standard deviations below young adults)
measured by segmental calf BIS
6. voluntary participation, written informed consent
to participate in study by participant or her/his
closest proxy.
7. plasma creatinine <150 μmol/l
8. no terminal illness (estimated prognosis >6 months)
9. no pacemaker
10. no bilateral replacement arthroplasty of the knee
11. no severe skin lesions in BIS electrode placement
sites (dorsal foot, dorsal ankle, lateral knee, dorsal
wrist, and dorsal palm)
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Those persons fulfilling inclusion criteria are invited to
participate. All participants are asked for an informed
consent before the start of any trial procedures. In case
of the participants’cognitive decline (Mini Mental State
Examination (MMSE) <19) [20] or poor capability of judg-
ment, the proxy is invited to give consent in addition to
receiving consent of the participant. The recruitment of
patients will be completed during 2013.
Study procedures
The first baseline study visit (day clinic or home visit) in-
cludes the measurement of hand grip strength, habitual
gait speed, and BMI. Patients with low hand grip or slow
gait speed will be further evaluated for their nutritional
status. These patients will be also further examined during
second baseline study visit (day clinic or home visit) includ-
ing cognition, segmental BIS, physical performance, muscle
power, and muscle endurance. In addition, the question-
naire data will be confirmed and deep frozen (−20 Celsius)
blood samples collected.
Two consecutive measures of handgrip strength (kg) at
both hands are measured to the nearest 1.0 kg with subjects
sittinginanuprightpositionandthearmina90-degree
angle (JAMAR dynamometer, Saehan Corp. Masan, Korea)
[17]. The mean of the best result from both hands will
be recorded. Habitual gait speed is measured over a 4-m
course without a walking aid when possible and the best
time of two attempts will be recorded to calculate the
gait speed = distance (m)/time (s) [18]. SMI will be mea-
sured with a single channel, tetra polar BIS device (SFB7,
ImpediMed Ltd., Eight Miles Plains, Queensland, Australia)
that scans 256 frequencies between 4 kHz and 1000 kHz.
Raw data are analyzed with the supporting software
(version 5.3.1.1, SFB7, ImpediMed Ltd., Eight Miles Plains,
Queensland, Australia) supplied by the manufacture to
obtain values for the calculation of SMI (SMI = electro
distance
2
/calf intracellular resistance [6,19]). In addition
to the participants, SMI will be also measured in young
healthy adults to provide the cut-points for low SMI
values. Physical performance will be assessed by the
short physical performance battery (SPPB) [21], which
consists of three components: balance, gait speed, and
chair rise ability. Scores of 1 to 4 are based on categories of
performanceinthebalancetests,onthetimenecessaryto
complete the walk, and on the time needed to perform the
chair-rise test. A summary performance score of 0 to 12
will be calculated by summing the scores of the tests. These
three components (balance, gait speed, and chair rise) will
also used to calculate continuous summary physical per-
formance scores (CSPPS = 0 to 100) [22,23] Muscle power
will be measured by the Takai et al. chair stand test [24]
andmuscleendurancebythetwo-minutesteptest[25].
Nutritional status will be assessed by the Mini Nutritional
Assessment (MNA) [26], the dietary quality questionnaire
[27] and the three-day dietary record [28]. Cognition will
be assessed by the Clinical Dementia Rating Scale (CDR)
[28], the Mini Mental State Examination (MMSE) [20],
verbal fluency [29,30], and the clock drawing test [31].
Health-related quality-of-life (HrQOL) will be assessed
by SF-36 [32] and 15D [33] measures. Participants will
be examined by the research group three times during
the year: at baseline, and at 6, and 12 months. The flow
chart of the study is presented in Figure 1, and study
assessment procedures are described in Table 1. Hospitali-
zations, use of other health and social services and death
dates will be retrieved from the central registers until two
years from baseline measurements.
After receiving an informed consent the patients fulfill-
ing the inclusion criteria are randomized by computer-
generated random numbers (Microsoft Excel 2010,
Redmond, WA, USA) into three arms: 1) no supplementa-
tion, 2) protein supplementation, and 3) isocaloric placebo.
First a list including 100 sets of the numbers 1, 2, and 3 in
random order is computer-generated to indicate each treat-
ment group, which results in a list of 300 open slots with
100 slots for each treatment group. At the time of each
patient recruitment a random number between 1 and 3 is
computer-generated to indicate the open slot in the original
list (1 = first open slot, 2 = second open slot, 3 = third open
slot) to rule out the selection bias by the research group.
The group treatment is randomized off-site and the content
of the supplement (protein supplement versus isocaloric
placebo) is kept sealed outside the research group until data
collection and analysis of endpoints are complete. Further-
more, all the supplements are packed in blank 250-ml tetras
and flavored with strawberry.
Intervention
All participants receive instructions on simple home-based
exercises, dietary protein and vitamin D supplementation.
The home-based exercises are based on the national
recommendations (www.voimaavanhuuteen.fi) to support
walking and the role of chair, stand and step exercises are
emphasized with written instructions. The participants are
instructed to exercise 10 to 30 minutes twice a day. Partici-
pantsarealsogivenwritteninformationondietaryprotein
and nutrition in old age based on national recommenda-
tions (www.ravitsemuskotona.fi) as well as encouraged to
use vitamin D supplementation with a dose of 20 μg/d.
The three arms of the intervention include: 1) no supple-
mentation, 2) protein supplementation, and 3) isocaloric
placebo. In groups 2 and 3 the participants are instructed
to take twice daily a 250 ml beverage as a snack between
meals immediately after an exercise session, whereas in
group 1 the participants are instructed to take regular
protein rich foods in similar fashion. In the protein
supplementation group the participants will receive a
maximum of 40 grams (20 grams x 2) of extra milk derived
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proteins daily compared with 7.5 grams (3.75 grams x 2) in
the isocaloric placebo group. After each exercise session
and ingestion of supplement the participants will record
the level of exercise and amount of ingested supplement
in a dairy. The compliance to the home-based exercises,
nutritional supplements and vitamin D supplement is
assessed also by interviewing the patients during each study
visit. The intervention will last for 12 months. The nutri-
tional contents of the protein supplement and isocaloric
placebo are shown in Table 2. All supplements are manu-
factured and provided by Valio Ltd, Helsinki, Finland.
Outcome measurements
The examinations are performed at 0, 6 and 12 months.
In addition to this, follow-up data are also collected from
registries at 24 months.
Primary outcome measures are:
1. The 6- and 12-month changes in physical performance
according to mean SPPB [21] and CSPPS [22,23]scores
2. Changes in muscle functions according to hand grip
strength [17], gait speed [18], balance [19], chair
stand test [24], two-minute step test [25]
Secondary outcome measures are:
1. Compliance to supplementation and home based
exercises
2. Patient reported benefits and adverse effects
3. Changes in nutrition according to MNA [26],
diet quality questionnaire [27], and dietary
records [28]
4. Changes in body composition according to BMI and
segmental BIS measurements [6,19]
5. Changes in cognition according to MMSE [20],
verbal fluency [29,30] and clock drawing test [31],
and CDR sum of boxes [35]
6. Changes in HrQOL measures according to SF-36
[32] and 15D [33]
7. Number of falls
8. Serum and plasma markers of inflammation,
anabolism, glycemic control and renal function
9. Use of health care (number of hospitalization/
follow-up time) and social services (number of
institutionalization/follow-up time) during a
24 month follow-up
10. Mortality during a 24 month follow-up
Figure 1 Flow chart [34].
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Statistical analyses
Required sample size calculation (PS: Power and Sample
Size Calculations version 3.0.43, Nashville, TN, USA) is
based upon the change in SPPB. A change of 0.5 in SPPB
score has been defined as minimally important and change
of 1.0 as substantially important. With a standard deviation
(SD) of 2.0 for SPPB, a type I error rate of 5%, a power of
80%, and a drop-out rate of 25%, we will need approxi-
mately 80 patients in each group to detect a substantial
change in SPPB, when the effects of protein supplementa-
tion are compared against no additional supplementation
or isocaloric placebo with a Student’s t-test independently.
Multiple comparison will be performed by Dunnett’stest
[36].Thefinalsamplesizemaydifferslightlyfromthis
figure, because we will recruit participants from the
entire 75 years and older population living in Porvoo,
Finland, and the aim is to include as many as possible
from those answering the postal questionnaire.
The statistical analyses will be performed by PASW
statistics 18.0.3 (SPSS Inc. Chicago, IL, USA). In the
baseline findings, for the continuous variables, descriptive
values will be expressed by means with SD and medians
with range. For the variables with a normal (Gaussian)
distribution, statistical comparisons between the groups
will be made by using an analysis of variance test. If the
variables have a non-normal distribution or ordinal level,
statistical comparison between groups will be performed
with an independent samples Kruskal-Wallis test. Mea-
sures with a discrete distribution will be expressed as
percentages(%)andanalyzedbyX
2
or Fisher’s exact test
when appropriate.
The results will be analyzed according to intention
to treat. For the most important outcome parameters
estimation of confidence interval (95%) will be used in
addition to testing.
Discussion
This rigorous randomized controlled trial will test whether
and to what extent protein supplementation is able to
maintain physical performance in community dwelling
older people with sarcopenia. In addition to protein supple-
mentation, the systematic use of simple and evidence-based
Table 1 Study assessment procedures and timetable
Assessment Postal questionnaire Baseline 6 months 12 months 24 months
Demographics, diagnoses, drugs, supplements, exhaustion, walking aid X
Inclusion criteria, informed consent X X
Physical activity X X X X
15D
1
and SF-36
2
QOL measures X X X X
MNA
3
, dietary quality questionnaire, dietary record X X X
BMI
4
, SMI
5
XX X
Hand grip strength (Bohannan 2008) X X X
SPPB
6
XX X
Takai chair stand test (Takai et al. 2009) X X X
Two-minute step test (Rikli and Jones 1999) X X X
CDR
7
XX X
MMSE
8
XX X
Verbal fluency (Morris et al. 1989), clock drawing test
(Sunderland et al. 1989)
XX X
Deep frozen blood samples X X X
Falls XX X
Hospitalization, use of health and social services, mortality X X
1
15D = health related quality of life scale (Sintonen et al. 1990);
2
SF-36 = health related quality of life scale (Hays et al. 1993);
3
MNA = mini nutritional assessment
(Guigoz et al. 2002);
4
BMI = body mas s index;
5
SMI = skeletal muscle index (Björkman et al . 2012);
6
SPPB = short physical performance battery (Guralnik et al. 1994);
7
CDR = Clinical deme ntia Rating Scale (Hughes et al. 1982);
8
MMSE = Minimental State Examination (Folstein et al . 1972). Questionnaires will be in Finnish or
Swedish according to participant’s first language.
Table 2 Nutritional content of the supplements
Protein
supplement 100 g
Isocaloric
placebo 100 g
Proteins (of which whey), g 8.3 (4.0) 1.0 (0.2)
Carbohydrates (of which lactose), g 7.0 (0.0) 14.0 (0.0)
Fat, % 1.0 1.0
Energy, kcal 70.0 70.0
Vitamin D, ug 1.0 0.2
All supplements are manufactured and provided by Valio Ltd, Helsinki, Finland.
Bjorkman et al. Trials 2013, 14:387 Page 5 of 7
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methods to maintain muscle health in old age including
home-based exercise, vitamin D supplementation and
protein rich foods are promoted among all participants.
The intervention is pragmatic in nature, and is performed
in close collaboration with the municipal health care
services. Thus, if the intervention proves to be effective,
it can be implemented easily.
The strength of this study is its pragmatic nature [37].
Thus, the findings should be applicable in real life. The
target population is frail and vulnerable and, according
to our previous studies, is at risk of adverse outcomes
such as physical disability and poor quality of life and
death. Thus, ceiling effect is not easily reached in the
primary endpoint. Furthermore, the limited exclusion
criteria and portable nature of all study procedures allow
the inclusion those disabled older people that are other-
wise often not included in clinical trials.
However, there are also potential limitations in this
study. First, the population is old and frail with many
comorbidities, and, thus, vulnerable to competing causes of
complications and deaths. This may decrease the power
of the study. The second challenge relates to a sufficient
difference to be attained between the groups with our
intervention because nutritional supplementation may
diminish the intake of regular food. Furthermore, the
long-term adherence of patients to single taste supple-
ments and unsupervised home-based exercises is also a
challenge to this study.
To our knowledge, this is the first large scale randomized
controlled trial among community dwelling older people
with sarcopenia that focuses on the effects of protein
supplementation on physical performance and several
aspects of muscle health, nutritional status, QoL, cog-
nition and hospitalizations.
Trial status
Recruiting was underway at time of manuscript submission.
Abbreviations
BIA: Bioimpedance analysis; BIS: Bioimpedance spectroscopy; BMI: Body mass
index; CDR: Clinical dementia rating scale; DEXA: Dual x-ray absorptiometry;
DSM-BIA: Direct segmental multifrequencymeasurements;HrQOL: Health-related
quality-of-life; MMSE: Minimental state examination; MNA: Mini nutritional
assessment; QOL: Quality of life; SD: Standard deviation; SMI: Skeletal muscle index;
SPPB: Short physical performance battery.
Competing interests
Dr Mikko Björkman reports professional cooperation including lecturing fees
from Valio Ltd. Dr Pitkälä reports having professional cooperation including
lecturing fees from pharmaceutical and other health care companies
(including Janssen-Cilag, Lundbeck, MSD Finland, Orion, Pfizer, Novartis, Nestle),
and having participated in clinical trials funded by pharmaceutical companies.
Merja Suominen, Dr Harriet Finne-Soveri, and Dr Reijo Tilvis have no
competing interests.
Authors’contributions
MPB, MHS, KHP, F-SUH, and RST participated in study conception and design;
MPB, MHS, KHP, F-SUH, and RST participated in acquisition of data, or analysis
and interpretation of data; and MPB, MHS, KHP, F-SUH, and RST participated in
drafting or critically revising the manuscript for important intellectual
content. MPB had full access to all of the data in the study and takes
responsibility for the integrity of the data and the accuracy of the data
analysis. MPB is the guarantor. Valio Ltd. and other funders of this study
will have no author contributions. All authors read and approved the final
manuscript.
Acknowledgements
This study is funded by University of Helsinki, by a special governmental
subsidy for health sciences research and training to Helsinki University
Central Hospital, by Yrjö Jahnsson Foundation and by Konung Gustaf
V:s och Drottning Victorias Frimurarestiftelse. The study is conducted in
collaboration with the municipal health care and social services of
Porvoo, Finland. All supplements are manufactured and provided by Valio
Ltd, Helsinki, Finland.
Author details
1
Geriatric Unit, Department of Internal Medicine, University of Helsinki, PO
Box 340, 00029 HUS Helsinki, Finland.
2
Society for Memory Disorders
Expertise in Finland, Fredriksberginkatu 2, 00240 Helsinki, Finland.
3
Unit of
General Practice, Helsinki University Central Hospital, Department of General
Practice, University of Helsinki, PO Box 20, 00014 Helsinki, Finland.
4
National
Institute for Health and Welfare, P.O. Box 30, FI-00271 Helsinki, Finland.
Received: 3 January 2013 Accepted: 28 October 2013
Published: 14 November 2013
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doi:10.1186/1745-6215-14-387
Cite this article as: Bjorkman et al.:Porvoo sarcopenia and nutrition trial:
effects of protein supplementation on functional performance in home-
dwelling sarcopenic older people - study protocol for a randomized
controlled trial. Trials 2013 14:387.
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