Acromegaly: Balance, Falls and Fracture Risk
Conditions: Acromegaly
Sponsor: Christian Alexander H Rosendal

Research protocol – Acromegaly: balance, falls and fracture risk 
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RESEARCH PROTOCOL 
ACROMEGALY: BALANCE, FALLS AND 
FRACTURE RISK 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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ACROMEGALY: BALANCE, FALLS AND 
FRACTURE RISK 
GENERAL INFORMATION 
Principal investigator: Christian A. H. Rosendal, MD 
 
Supervisor: Jakob Dal, MD, PhD 
 
Trial site: Department of Endocrinology, Aalborg University Hospital, Mølleparkvej 4, 9000 Aalborg 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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TABLE OF CONTENTS 
General information ........................................................................................................................... 2 
I: Title ....................................................................................................................................................... 4 
II: Background, aims and hypotheses .......................................................................................... 5 
A. 
Background ...................................................................................................................................... 5 
B. 
Acromegaly and musculoskeletal disorders ........................................................................ 5 
C. 
Objectives ......................................................................................................................................... 7 
III: Methods ............................................................................................................................................ 7 
A. 
Study design .................................................................................................................................... 7 
B. 
Study population ............................................................................................................................ 7 
C. 
Assessment of resources ............................................................................................................. 9 
D. 
Study procedures ........................................................................................................................... 9 
High Resolution peripheral Quantitative Computed Tomography (HR-pQCT) ............................................. 10 
Whole body Dual X–ray Absorptiometry (DXA) scan and vertebral fracture assessment ........................ 11 
Microindentation, Bone Material Strength index (BMSi) and the OsteoProbe® .......................................... 11 
Hand Grip Strength (HGS) and leg extension strength .............................................................................................. 11 
Timed Up-and-Go (TUG) ......................................................................................................................................................... 12 
Stabilometry ................................................................................................................................................................................ 12 
Nerve conduction test .............................................................................................................................................................. 12 
Visual acuity test ........................................................................................................................................................................ 12 
Questionnaires ............................................................................................................................................................................ 12 
Biochemical bone markers and blood samples ............................................................................................................ 13 
IV: Data collection ............................................................................................................................ 13 
V: Data analysis ................................................................................................................................. 14 
A. 
Statistical methods ..................................................................................................................... 14 
Sample size calculation ........................................................................................................................................................... 14 
Statistical methods .................................................................................................................................................................... 14 
Statistical significance ............................................................................................................................................................. 14 
VI: Data safety .................................................................................................................................... 14 
VII: Study limitations ....................................................................................................................... 14 
VIII: Ethical considerations ........................................................................................................... 14 
A. 
Informed consent ........................................................................................................................ 14 
B. 
Risks and side effects ................................................................................................................ 15 
C. 
Benefits to subjects .................................................................................................................... 16 
D. 
Costs to subjects .......................................................................................................................... 16 
E. 
Compensation to subjects ........................................................................................................ 17 
F. 
Plan for dissemination of findings ........................................................................................ 17 

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G. 
Economy ......................................................................................................................................... 17 
IX: References ..................................................................................................................................... 17 
 
I: TITLE 
Acromegaly: balance, falls and fracture risk. 
List of abbreviations:  
GH: Growth Hormone 
IGF-1: Insulin-like Growth Factor 1 
SSA: Somatostatin Analog 
DA: Dopamine Agonist 
HR-pQCT: High Resolution peripheral Quantitative Computed Tomography 
HGS: Hand Grip Strength 
TUG: Timed Up-and-Go 
DXA: Dual X-ray Absorptiometry 
BMSi: Bone Material Strength Index 
vBMD: Volumetric Bone Mineral Density 
BMI: Body Mass Index 
VFA: Vertebral Fracture Assessment 
mSv: Milli-Sievert 
CoP: Center of Pressure 
WOMAC: Western Ontario and McMaster universities osteoarthritis Index 
FES-I: Falls Efficacy Scale International 
P1NP: procollagen-1 N-terminal propeptide a marker of bone formation) and  
CTX: cross-linked C telopeptide of type I collagen 
PTH: Parathyroid Hormone 

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EPJ: Eletronic Patient Journal 
II: BACKGROUND, AIMS AND HYPOTHESES 
A. BACKGROUND 
Acromegaly is a rare systemic disease characterized by hypersecretion of growth hormone (GH) from a 
pituitary adenoma, and consequently pathologically high levels of insulin-like growth factor I (IGF-I). 
Symptoms develop insidiously and include acral growth, coarse facial features and organ enlargement. 
The incidence of acromegaly is most often reported to be approximately 3-5 cases per 106 per year1–5 
whereas the reported prevalence varies considerably between studies from 20 - 85 cases per 106 6.  
Acromegaly is associated with several comorbidities including diabetes mellitus, hypertension, heart 
failure, thromboembolic events, ischemic heart disease, increased cancer risk, arthropathy and 
osteopathy, and untreated it is associated with a significant reduction in quality of life and life 
expectancy2,7. 
The preferred treatment, when feasible, is transsphenoidal surgical removal of the pituitary adenoma, 
which is performed in 60-80% of patients in Denmark. Medical treatment includes somatostatin analogs 
(SSAs), the GH receptor antagonist Pegvisomant and dopamine agonists (DAs), while radiotherapy is 
rarely used2. With optimal treatment and normalization of GH and IGF-I, acromegalic patients have a 
mortality rate close to that of the general population1. If left untreated, however, acromegaly is associated 
with an increased mortality, mainly due to cardiovascular complications8. 
B. ACROMEGALY AND MUSCULOSKELETAL DISORDERS 
Of the acromegaly-related comorbidities, arthropathy is associated with a markedly reduced quality of 
life due to pain, reduced mobility, impaired activities of daily living as well as reduced work productivity 
and increased risk of early retirement9. Arthropathy is one of the most frequent complications of 
acromegaly, affecting more than 70% of all patients10,11. Acromegalic arthropathy is characterized initially 
by cartilage hypertrophy, joint space widening and osteophytosis, whereas in later stages it assumes 
features similar to primary osteoarthritis, such as joint space narrowing, subchondral cysts and bone 
edema11,12. In early stages of acromegalic arthropathy, progression of the condition may be halted or even 
reversed by achieving biochemical control/remission, but in later stages the arthropathy becomes 
irreversible and persistent even despite successful treatment of the underlying condition. However, 
acromegalic arthropathy has even been found to slowly progress despite achievement of disease control2.  
No effective treatment, except for surgical arthroplasty and analgesics, exists for this debilitating 
condition11. Novel imaging techniques such as HR-pQCT have not yet been applied in the field of 
acromegalic arthropathy, and may further our understanding of the condition, potentially leading to new 
treatment options. HR-pQCT imaging of joints is common in research regarding inflammatory joint 
diseases13, but thus far, no studies exist regarding HR-pQCT joint imaging in acromegalic patients. 

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Studies concerning balance and falls among acromegalic patients remain scarce. Thus far, it has been 
suggested that acromegalic patients have impaired balance and postural control, due to factors such as 
alterations in body composition, enthesopathy, myopathy, arthropathy or visual field disturbances14–16. 
Indeed, altered body composition has been demonstrated in acromegalic patients using whole-body DXA 
scans17,18 and reduced peripheral muscle strength has been found using hand grip strength (HGS) as a 
measure19. Moreover, an increased fear of falling has been observed in patients with acromegaly, 
although the frequency of falling seems to be similar to healthy controls16. However, fall risk, as evaluated 
via the timed up-and-go (TUG) test, has been shown to be increased in acromegalic patients20.  
An improvement in several dynamic balance parameters, as evaluated by stabilometry, has been 
demonstrated among acromegalic patients after a relatively short training program, indicating a potential 
benefit of focused physical therapy for this patient group14. Given that acromegalic patients have 
impaired bone quality, preventing falls may be of considerable clinical relevance. However, this subject 
calls for further investigations14–16. To our knowledge, no studies have directly compared body 
composition and dynamic muscle parameters such as hand grip strength, leg extension strength, timed 
up-and-go and stabilometry in acromegalic subjects. 
Acromegaly-related osteopathy has been a subject of interest in recent years, as it has been established 
that patients with acromegaly have increased bone turnover, reduced bone quality and an increased risk 
of fractures despite normal bone mineral density as assessed by DXA-scans21. Secondary hypogonadism 
due to tumor mass effect or pituitary surgery plays a significant role in the diminished bone quality of 
acromegalic patients, even after disease control is achieved21. 
Acromegalic subjects have been found to have reduced quality of the trabecular bone compartment, 
increasing the risk of vertebral fractures, which have indeed been found to be prevalent among 
acromegalic patients22–25. Using High-Resolution peripheral Quantitative Computed Tomography (HR-
pQCT), significantly reduced measurements of both trabecular and cortical volumetric bone mineral 
density (vBMD) have been reported in acromegalic patients18,26, even during biochemical disease 
control26. Disease duration and presence of hypogonadism appear to be the most influential risk factors 
for this impaired bone quality, although even eugonadal acromegalic patients have reduced trabecular 
bone quality18,26,27. HR-pQCT-derived bone parameters can be used to calculate physical properties such 
as bone stiffness and failure load, which has previously been performed in acromegalic patients, revealing 
no difference between acromegalic patients and healthy controls in this regard18. However, compromised 
bone quality has been confirmed ex vivo by means of iliac crest bone biopsies in a study of acromegalic 
patients, reporting both lower trabecular thickness and increased trabecular separation in acromegalic 
patients with vertebral fractures but normal BMD, as assessed by DXA scan28. 
Although normal or even increased cortical bone thickness has been reported using iliac crest bone 
biopsies28, hip structure analysis29 and high-resolution cone beam tomography30, other cortical bone 
parameters such as bone material strength index (BMSi) have been shown to be reduced, even in well-
controlled acromegalic patients31, suggesting compromised bone fracture resistance in acromegalic 
patients. Decreased BMSi, as measured by micro-indentation using an OsteoProbe, has been shown to be 

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correlated with fragility fractures in postmenopausal women and in individuals with diabetes31,32. Only 
one study31 has measured BMSi on acromegalic subjects and found significantly lower values compared to 
healthy controls, regardless of biochemical control, hypogonadism or presence of vertebral fractures. If 
and how BMSi values correlate to reduced bone quality, as assessed by HR-pQCT, remains to be examined 
in patients with acromegaly. Thus far, no studies exist regarding the integration of HR-pQCT-derived bone 
parameters, BMSi and the presence of vertebral fractures. By combining these diagnostic modalities, we 
aim to perform an integrated assessment of bone quality in acromegalic patients, examining both the 
cortical and trabecular bone compartments to further our understanding of acromegalic osteopathy.  This 
may provide more insight into which diagnostic modality is optimal as a measure of fracture risk in 
acromegalic patients, since standard DXA scans have proved less useful in this regard21. 
 
C. OBJECTIVES 
Aim: 
A. To perform a comprehensive, integrated assessment of balance, bone and joint quality, body 
composition, muscle strength, fear and risk of falling and fracture risk of acromegalic patients.  
Hypotheses: 
A. Acromegalic patients have impaired bone quality (as assessed by HR-pQCT and BMSi), impaired 
balance, and increased risk of falling. Combining multiple diagnostic modalities will improve our 
understanding of the pathophysiological mechanisms behind acromegalic osteopathy. 
III: METHODS 
A. STUDY DESIGN 
The study will be performed as a cross-sectional study examining patients with acromegaly and healthy 
controls. Participants will be informed about the study both orally and in writing and will be recruited 
from the pituitary endocrinology outpatient clinic at Aalborg University Hospital.  
Healthy controls will be recruited via social media and websites such as www.forsøgsperson.dk. An 
existing database where participants have given written consent (within the last year) to be contacted 
regarding research projects may also be used. This database is created and administrated by the North 
Denmark Region, and approved by its legal staff. Potential participants are required to use a secure access 
(NemID), and if they do not actively renew their consent within a year, it is automatically withdrawn.   
B. STUDY POPULATION 

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We plan to include thirty male or female patients with acromegaly and thirty age- (+/- 5 years), BMI- (+/- 
5 points), and sex-matched non-acromegalic control subjects. 
Inclusion criteria for the acromegalic group: 
1. Verified acromegaly diagnosis 
2. Age ³18 years 
3. Ability to provide informed consent 
4. Ability to stand on both legs for ³5 minutes at a time and walk ³6 meters 
5. Patient is eugonadal, either naturally or by hormone replacement therapy 
Exclusion criteria for the acromegalic group: 
1. Established diagnosis of severe kidney or liver dysfunction, malabsorption, multiple myeloma or 
other diseases associated with reduced bone quality 
2. Treatment with supraphysiological doses of glucocorticoids or other drugs that impair bone 
quality 
3. Diagnosis of rheumatoid arthritis, psoriatic arthritis or other joint diseases unrelated to 
acromegaly 
4. Active drug or alcohol abuse 
5. Pregnancy 
6. Known allergy/hypersensitivity to local anaesthetics or disinfectant 
7. Other factors that render the subject unable to participate in the clinical study, based on the 
judgment of the investigator(s)  
The control subjects will be recruited via social media, the aforementioned database and websites, and 
matched to the acromegalic study population.  
Inclusion criteria for the control group: 
1. Age ³18 years 
2. Ability to provide informed consent 
3. Ability to stand on both legs for ³5 minutes at a time and walk ³6 meters 
Exclusion criteria for the control group: 
1. Established diagnosis of severe kidney or liver dysfunction, malabsorption, multiple myeloma, 
diabetes or other diseases associated with reduced bone quality 
2. Treatment with supraphysiological doses of glucocorticoids or other drugs that impair bone 
quality 
3. Diagnosis of rheumatoid arthritis, psoriatic arthritis or other joint diseases 
4. Active drug or alcohol abuse 
5. Pregnancy 

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6. Known allergy/hypersensitivity to local anaesthetics or disinfectant 
7. Other factors that render the subject unable to participate in the clinical study, based on the 
judgment of the investigator(s)  
C. ASSESSMENT OF RESOURCES 
This study will be conducted in collaboration with the department of endocrinology of Aalborg University 
Hospital, wherefrom patients will be recruited and the physical locale for the procedures provided. The 
department has access to experienced personnel, who are trained in the use of both HR-pQCT and DXA 
scanners, and the Osteoprobe. Personnel and equipment for biochemical sampling are also accessible. 
For assistance with the procedures regarding balance and postural control, we will collaborate with 
Rogerio P. Hirata under the group of Prof. Thomas Graven-Nielsen at Aalborg University, who is 
experienced in the use of the balance pad and interpretation of the results it yields.  
D. STUDY PROCEDURES 
Patients with an established diagnosis of acromegaly will be recruited from December 2022 to March 
2025. Patients will be informed of the study during scheduled visits to the pituitary endocrinology 
outpatient clinic at Aalborg University Hospital by one of two specialists in pituitary endocrinology. 
Patients will be given information regarding the study, and if interested, they will be provided with a form 
to fill out with their contact information, so they can be contacted by the investigators or other staff 
affiliated with the study. Should the patient agree to be contacted via telephone or e-mail, they will be 
given an instruction regarding their rights as a participant in a scientific study (“Dine rettigheder som 
forsøgsperson i et sundhedsvidenskabeligt forskningsprojekt”) as well as written material specifically 
pertaining to the study (“Deltagerinformation”). Should the subject be deemed fit for the study, based on 
the in- and exclusion criteria, contact will be made via phone or e-mail and they will receive further 
information regarding the study, and offered a personal meeting with one of the investigators, where 
details of the study procedures will be outlined. The meeting will take place in a dedicated, undisturbed 
office at the disposition of the Department of Endocrinology, in order to ensure due privacy during the 
meeting. In advance, the subject will be informed of the opportunity to bring a relative or other 
representative to the meeting. At the meeting, the participant and any representative will be informed of 
the 24-hour deliberation period before providing informed consent. No study procedures will be 
performed until the informed consent form has been signed by both the participant and the investigator.  
As mentioned above, healthy controls will be recruited via the aforementioned database, social media and 
websites such as www.forsoegsperson.dk. Potential participants who contact the principal investigator 
through these channels will be provided with written material pertaining to the study 
(“Deltagerinformation”) and a description of their legal rights as a participant (“Dine rettigheder som 
forsøgsperson i et sundhedsvidenskabeligt forskningsprojekt”). Should the potential participant meet the in- 
and exclusion criteria, they will be invited to a personal meeting, where details of the study are explained, 

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having been informed of the opportunity to bring a representative or relative to the meeting in advance. 
Should they wish to participate, a 24-hour deliberation period will be given prior to obtaining written 
informed consent. 
After providing informed consent, the participants will undergo a series of study procedures. Bone quality 
will be assessed by way of High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT) 
images of the distal radius and tibia. Bone material strength index (BMSi) is assessed using an 
OsteoProbe. In addition to this, postural control will be assessed using a balance board to obtain a 
surrogate measure of fall risk. Body composition, bone mineral density and vertebral fracture assessment 
(VFA) will be analyzed via Dual X-ray Absorptiometry (DXA) scans and peripheral muscle strength will be 
assessed via hand grip strength and knee extension torque measurements, and visual acuity tested with 
standard methods. Data will be analyzed using relevant statistical analyses and presented as a cross-
sectional study.  
HIGH RESOLUTION PERIPHERAL QUANTITATIVE COMPUTED TOMOGRAPHY (HR-
PQCT) 
HR-pQCT is a 3-dimensional imaging modality that can be applied to bone and joints in vivo, in order to 
non-invasively assess the quantity and quality of trabecular and cortical bone compartments separately. 
HR-pQCT will be applied to peripheral skeletal sites, namely the distal radius and tibia, where image 
slices equivalent to 9 mm of bone will be acquired. From this, parameters such as volumetric bone 
mineral density (vBMD), cortical density, cortical porosity, trabecular density, trabecular thickness, 
trabecular spacing and others will be calculated using specialized software.  In the same scanning session, 
images of the wrist and ankle joints will be produced and analyzed for features of arthrosis, such as 
erosions, osteophytosis and others. 
The scanner’s gantry is relatively narrow and shallow (rear physical stop) only allowing the distal 
peripheral skeleton to be accommodated. The limb being scanned is immobilized in a carbon fiber shell. A 
scout view, essentially a two-dimensional x-ray scan, is obtained so that the operator can identify a 
precise region for the three-dimensional measurement. Because HR-pQCT uses a polychromatic X-ray 
source it is subject to beam hardening as well as scatter artefacts, which can significantly impact 
geometric and densitometric measures. Once the images have been acquired, a default patient evaluation 
protocol is used to analyze the scans over the entire 9 mm three-dimensional region to assess a wide 
range of standard and optional structural and density parameters.  
The effective radiation dose for one HR-pQCT scan at the distal tibia or radius is 0,003 – 0,005 mSv, which 
is considered a low radiation dose33. In comparison, a regular chest X-ray yields a dose of 0,01 – 0,1 mSv 
and dental X-ray yields 0,005 mSv. The worldwide average effective radiation dose from natural 
background radiation is 2,4 mSv per year. The average effective radiation dose in Denmark is 3 mSv per 
year. 

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Estimated time: 30 min. 
WHOLE BODY DUAL X–RAY ABSORPTIOMETRY (DXA) SCAN AND VERTEBRAL 
FRACTURE ASSESSMENT 
Through DXA scans, we will obtain information regarding body composition, hip and spine bone mineral 
density, as well as examine any previous vertebral fractures using vertebral fracture assessment (VFA). 
VFA is a function of DXA scanners which allows for visualization of thoracic and lumbar vertebrae 
(usually T4-L4) in order to detect vertebral fractures34. Vertebral fractures can then be classified as either 
mild, moderate or severe using the method described by Genant et al35. 
The effective radiation dose is between 0,001 and 0,01 mSv for one whole body DXA scan, between 0,003 
and 0,03 mSv for one hip and lumbar spine DXA scan and 0,003 mSv for one VFA scan. As such, the total 
effective radiation dose for the DXA scans is between 0,007 and 0,043 mSv.  
The whole body DXA scan, hip and lumbar spine DXA scan and VFA scan will be performed consecutively. 
Estimated time: 50 min. 
MICROINDENTATION, BONE MATERIAL STRENGTH INDEX (BMSI) AND THE 
OSTEOPROBE® 
Using the OsteoProbe®, we will by microindentation measure the bone material strength index (BMSi), 
an in vivo surrogate measure of the fracture resistance of the cortical bone in the tibia. The participant is 
placed in a supine position with the examined leg rotated slightly outward. After identifying the site of 
interest, located midway between the medial tibial plateau and the medial malleolus, disinfectant is 
applied to the skin of the tibia being examined. Finally, under local anesthesia and fully sterile conditions, 
a test probe is inserted through the skin and onto the midshaft of the tibia, and the fracture resistance of 
the bone tissue is measured. Without removing the probe from the skin, this process is repeated a 
minimum of eight (maximally 18) times to provide a sufficient number of measurements. By means of a 
synthetic polymer calibration phantom, the BMSi is calculated via specialized software provided by the 
manufacturer. After the procedure, a sterile bandage will be applied to the puncture site and all sharp 
and/or biohazardous materials will be disposed of in an appropriate manner. 
Estimated time: 20 min. 
HAND GRIP STRENGTH (HGS) AND LEG EXTENSION STRENGTH 
Hand grip strength will be assessed using a digital hand dynamometer as a measure of peripheral muscle 
strength. Leg extensor strength will be examined using the peak torque measured by an isometric 
dynamometer mounted on a fixed chair. 3 attempts will be given for each method, and the maximum 
value recorded. 

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Estimated time: 10 min. 
TIMED UP-AND-GO (TUG) 
The TUG test is a functional test frequently used to assess balance in older individuals and is performed 
by measuring the time it takes for an individual to go from sitting to standing position, walk 3 meters, 
turn around and return to sitting position. A TUG score of >13,5 seconds is associated with an increased 
risk of falls.  
Estimated time: 10 min. 
STABILOMETRY 
Postural control will be assessed by means of a force platform that registers Center of Pressure (CoP) as a 
measure of postural stability. Measurements are performed under a variety of conditions, including eyes 
open/closed and on different surfaces. From the CoP measurements, parameters such as CoP range and 
CoP velocity in both antero-posterior and medial-lateral directions will be calculated using specialized 
software. 
Estimated time: 20 min. 
NERVE CONDUCTION TEST  
To fully examine all components of balance, nerve conduction will be tested using a handheld device 
called NC-stat DPN-Check in order to assess any peripheral neuropathy. 
Estimated time: 10 min. 
VISUAL ACUITY TEST 
Visual acuity will be tested using an automated refractometer (KR-800S Auto-kerato-refractometer, 
Topcon Healthcare, The Netherlands). 
Estimated time: 10 min. 
Our laboratory has ample experience and know-how regarding the above-mentioned methods and their 
application in different patient groups. 
QUESTIONNAIRES 
Through questionnaires we will obtain information regarding previous falls and fractures, overall quality 
of life (Acro-QoL), joint-related symptoms (Western Ontario and McMaster universities osteoarthritis 
Index, WOMAC), fear of falling (Falls Efficacy Scale International, FES-I) and balance (Berg Balance Scale). 
Medicine lists will be collected from all participants. 

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BIOCHEMICAL BONE MARKERS AND BLOOD SAMPLES 
To assess biochemical markers of bone metabolism, we will measure fasting serum levels of procollagen-
1 N-terminal propeptide (P1NP, a marker of bone formation) and cross-linked C telopeptide of type I 
collagen (CTX, a marker of bone resorption) as well as sclerostin (an inhibitor of bone formation). To 
assess other hormones with influence on bone quality, we will measure levels of vitamin D and 
parathyroid hormone (PTH). In total, a volume of approximately 16mL of blood (4x 4mL vials) will be 
collected from each participant, both acromegalic and controls. For practical reasons, these blood samples 
are frozen after collection, stored in a research biobank, and analyzed in one session upon all participants’ 
completion of the study procedures. Before analysis, Danish Tissue Utilization Register 
(Vævsanvendelsesregistret) will be consulted; should the participant be listed herein, the blood sample 
will not be analyzed. After analysis, any remaining material will be destroyed. 
Two extra vials of blood (10mL total) will be extracted and stored in a biobank for future research, to 
enable analysis of any future bone markers or other biomarkers of interest for this project. An application 
will be submitted to the Danish Data Protection Agency in this regard. Blood samples will be frozen and 
stored in an encrypted fashion and in compliance with the Danish Data Protection Act for 15 years after 
completion of the study, or until their destruction is requested by the participant. Blood samples will be 
collected from both acromegalic subjects and healthy controls, in order to determine differences in 
biochemical markers between acromegalic subjects and control subjects. Participants will be asked to 
sign a separate consent form regarding storage of their biological material (blood sample) in a biobank 
for future research.  
All blood samples are stored in a freezer at -80 degrees Celsius. The freezer is located on the premises of 
Aalborg University Hospital (Mølleparkvej 4, room 20.01.130) and is only accessible by authorized 
personnel. Sample vials are marked only with a participant number, and the key to link each participant 
number to a specific participant will be stored on a secure server only accessible by personnel affiliated 
with the study. 
IV: DATA COLLECTION 
Following the participants’ informed consent, data regarding age, sex, medicine use and clinical 
information regarding acromegaly (duration, treatment, comorbidities, disease status and more) will be 
collected from the participants’ Electronic Patient Journal (EPJ). For both groups, anthropometric data 
such as height and weight will be gathered in relation to the DXA scans. The aforementioned data will be 
entered in a REDCap database on a secure server owned by the North Denmark Region. The information 
gathered is both for use in the research project itself and for mandatory quality assurance and 
monitoring, as per the Committee Act, §3, subsection 3. By providing informed consent, the participants 
acknowledge that the investigators, sponsors and relevant control authorities may access their Electronic 
Patient Journal with this intent.  

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V: DATA ANALYSIS 
A. STATISTICAL METHODS 
SAMPLE SIZE CALCULATION 
Based on another study using HR-pQCT on acromegalic subjects27, using the HR-pQCT-derived parameter 
“trabecular density”, mean values of 180 (SD: 40) and 150 (SD: 40) were found for controls and 
acromegalic patients, respectively. With a significance level of 5% and using 28 acromegalic subjects and 
28 controls, the power of this study will be 80% to demonstrate a difference in trabecular density of 30 
units.  
STATISTICAL METHODS 
Statistical testing will be performed using STATA® version 17 for Mac (StataCorp LLC, Texas, USA). 
Data will be summarized using descriptive statistics such as frequency, percentage, mean and standard 
deviation. Statistical testing will be applied to compare acromegalic subjects to healthy controls, including 
t-tests, chi-squared tests and Mann-Whitney U tests, where applicable. 
STATISTICAL SIGNIFICANCE 
We use a statistical significance level of a < 5%. 
VI: DATA SAFETY 
The project will be registered with the North Denmark Region and all sensitive data will be stored on the 
secure servers of Aalborg University Hospital or in a REDCap database administrated by this institution 
and in accordance with the Data Protection Act (databeskyttelsesloven). All stored data will be 
anonymized after termination of the project. No data will be given over to a third party. 
VII: STUDY LIMITATIONS 
Due to the study’s single-center nature, our findings may not be applicable to the entire population of 
acromegalic patients.  
VIII: ETHICAL CONSIDERATIONS 
A. INFORMED CONSENT 
The initial inquiry about participation of patients with acromegaly will be made by one of two specialists 
in pituitary endocrinology. Potential participants will receive both oral and written information 

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(“Deltagerinformation” and “Før du beslutter dig”). Further information will later be given, by the principal 
investigator or another member of the research team, and will include details about the tests involved: 
• 
This is a scientific project designed to investigate the optimal method for diagnosing acromegalic 
osteopathy, as well as testing balance and strength 
• 
Information regarding the included examinations, including the risk of minimal to moderate pain 
associated with the BMSi measurement and the minimal exposure to ionizing radiation 
associated with HR-pQCT and DXA scans 
• 
Information and separate consent regarding the creation of a biobank consisting of participants’ 
blood samples, which will be stored for future analysis, but no more than 15 years after 
completion of the study. A renewed application will be submitted to the regional ethics 
committee in case the research team should wish to analyze the blood samples in the future. 
Prior to analysis, the Danish Tissue Utilization Register (Vævsanvendelsesregistret) will be 
consulted; should the participant be listed herein, the blood sample will not be analyzed.  
• 
That withdrawal of consent, and as such withdrawal from participation, is possible at any time 
and with no given notice or explanation 
• 
That collected data will be published in anonymized form with no possibility of being traced to 
the participant 
• 
That collected data will be securely stored in accordance with the rules in place 
• 
That at least 24 hours are given to deliberate before providing informed consent 
• 
That potential participants have the right to bring a relative or other representative to the 
informational meeting 
Potential participants are given at least 24 hours to deliberate, before any consent form is signed.  
The project will be performed in compliance with the ICH GCP and the Helsinki Declaration for 
biomedical research involving human test subjects. The study will be subject to continuous internal 
quality monitoring, in accordance with GCP guidelines. 
The project will be prospectively registered with www.clinicaltrials.gov. 
B. RISKS AND SIDE EFFECTS 
All methods used have been tested in previous studies with no side effects being reported. The risks 
associated with the above-mentioned procedures are limited as only low-dose radiation is used, and all 
measures are taken to ensure sterility when relevant.  
No changes in the participants’ regular medication will be made, and no new medication will be 
administered, except for local anaesthetics given during the BMSi measurement. 

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16 
The main side effect that may be anticipated is pain in relation to the BMSi measurement, however 
relevant measures will be taken to counter this, and the pain is transient. Aside from this, there is a 
minimal amount of ionizing radiation from HR-pQCT and DXA scans, as mentioned above.  
These are the anticipated side effects related to each examination included in the protocol: 
• 
Blood samples: minimal risk of infection; disinfectant will be applied before skin puncture. Risk of 
small hematoma around the puncture site. 
• 
HR-pQCT scan: low dose of ionizing radiation (0,003 – 0,005 mSv). Mild discomfort from sitting 
still during the scan. 
• 
Whole body, hip and spine DXA and VFA: low dose of ionizing radiation (0,007 - 0,043 mSv).  
o 
Theoretically, the radiation doses associated with the HR-pQCT and DXA scans may 
increase the life-time risk of cancer from approximately 25% to less than 25,000003 %.  
• 
Microindentation (BMSi measurement): mild to moderate pain/discomfort related to 
administration of local anaesthesia. Mild to moderate pain when contact is made between the 
probe and the periosteum; local anaesthesia will be administered to alleviate this. Minimal risk of 
infection after skin puncture; the procedure will be performed under sterile conditions to 
minimize this risk.  
• 
TUG, stabilometry, hand grip strength, leg extensions, nerve conduction test, visual examination: no 
side effects or risks expected. 
As all the procedures are associated with a low risk of lasting side effects or complications, and the results 
of the study are expected to contribute to improved diagnosis and treatment of debilitating conditions in 
the future, the investigators consider the study procedures ethically responsible.  
C. BENEFITS TO SUBJECTS 
The participants will not benefit directly from participation in this study. However, as we aim to examine 
the optimal means of diagnosing acromegalic osteopathy, our findings may contribute to earlier detection 
of this condition. This is of potential future benefit for patients with acromegaly, as early diagnosis and 
treatment may prevent fractures, and thus save patients considerable morbidity. Identifying patients at 
risk for falling will enable treating physicians to implement relevant measures to prevent falls, and thus, 
potentially prevent fractures. Should HR-pQCT prove valuable in the diagnosis of acromegalic 
arthropathy, this may also be beneficial to patients in the future.  
As such, the potential future benefits to patients with acromegaly are deemed sufficient justification for 
performing the study.  
D. COSTS TO SUBJECTS 
Apart from transportation to the hospital to participate, no other costs will be incurred to participants. 
 

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17 
E. COMPENSATION TO SUBJECTS 
No economical compensation will be paid to participants.   
In case of unforeseen side effects or other adverse events related to the examinations, affected 
participants will be covered by the Danish Health Act and “patienterstatningsordningen”. 
F. PLAN FOR DISSEMINATION OF FINDINGS 
The results of the project are planned to take the form of a research article, to be published in an 
internationally acknowledged scientific journal such as JCEM or EJE. All data will be published in 
anonymized form. Results will be published regardless of submission acceptance or denial, and both 
positive, negative and inconclusive results will be published. 
G. ECONOMY 
The initiative for this project has been made solely by the main supervisor, Jakob Dal and PhD student, 
Christian Rosendal.  
Funding has been provided by research grants from Ipsen (€40.000, approx. 300.000 kr.) and Pfizer 
(500.000 kr.) as well as in-house research funds. The aforementioned pharmaceutical companies do not 
stand to gain financially from any specific result this project may yield. The grants are transferred to the 
endocrinology research department and cover the salary for the PhD student for three years, while 
expenses related to the practical aspects of the study (materials, analyses etc.) are covered by in-house 
funds . None of the investigators have any economical connection to, and are not employed by, the 
aforementioned pharmaceutical companies. The described funds sufficiently cover the completion of the 
study. 
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