Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12613001181796
Ethics application status
Approved
Date submitted
22/10/2013
Date registered
29/10/2013
Date last updated
1/08/2019
Date data sharing statement initially provided
1/08/2019
Type of registration
Retrospectively registered

Titles & IDs
Public title
The INDIGO Study - A randomised controlled trial of physical activity with individual goal-setting and volunteer mentors to increase physical activity in insufficiently active older adults at risk of cognitive decline.
Scientific title
The INDIGO Study - A randomised controlled trial of physical activity with individual goal-setting and volunteer mentors to increase physical activity in insufficiently active older adults at risk of cognitive decline.
Secondary ID [1] 283388 0
Nil
Universal Trial Number (UTN)
Trial acronym
INDIGO
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Those at risk of cognitive decline 290286 0
Physical inactivity 290372 0
Condition category
Condition code
Neurological 290677 290677 0 0
Alzheimer's disease
Public Health 290763 290763 0 0
Health promotion/education

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Both groups (intervention and control) will receive the same physical activity (PA) program (home-based, emphasis on walking) with a target of 150 minutes of moderate intensity PA/week. The program is progressive in duration and intensity taking 8 weeks to reach moderate intensity (55-65% heart rate reserve) for each individual. Participants will be asked to complete the PA as 3 x 50-minute sessions a week or 5 x 30-minute sessions a week. Intensity will be monitored using the Borg Perceived Rate of Exertion scale (RPE 10-12). All participants will receive a manual including the same information about exercise programs, exercise safety and community PA resource material. As part of the baseline workshop the facilitator will outline the PA program, explain the activities, how often they will be done, the intensity and how to record on their standardised PA diaries.

The intervention group will receive the Goal Orientation Intervention (GM-PA group). The participant’s individual goals will be identified on the Bangor Goal Setting Interview (BGSI) at baseline, in a face-to-face interview (approximately 60 minutes) with a member of the research team. Participants will be asked to select 5 personal goals from the physical function and PA areas. These goals will be operationalised and worked on during the 24- week intervention period with the development of individual strategies of how to achieve these goals. This program will be delivered via a participant manual and 3 group workshops conducted by research staff. These will be held in the first 6 months. The first will have a duration of two hours, and the remaining workshops will be of 1-hour duration at 8-weekly intervals.

Over the 6-month intervention period the mentors will make 6 calls at 4-week intervals starting at week 2 then weeks 6, 10, 14, 18 and 22. Peer mentors will attend a 5-hour training course on how to support the participants and facilitate the problem solving approach of the goal-setting program.Mentors will be assisted with telephone call scripts to carry out this task.

Adherence to the prescribed program will be assessed from self reported PA diaries. The mentors will also be monitoring adherence and keeping records via the telephone calls. The type, frequency, duration and intensity of the PA will be determined from these records. Adherence will be calculated as the number of minutes of moderate activity completed relative to the prescribed 150 minutes/week expressed as a percentage.

In the proposed study, a mentor will be an important and relevant source of information and support. We hypothesise that this approach combined with the goal oriented intervention package (goal-mentor, GM-PA) will result in greater improvements in PA and physical function than standard education and peer standard contact (control, CO-PA).

Community volunteers will be recruited and randomised to either be a peer goal-mentor for the intervention group or a Physical Activity Liaison for the Control group.
Intervention code [1] 288113 0
Treatment: Other
Intervention code [2] 288168 0
Behaviour
Intervention code [3] 288175 0
Lifestyle
Comparator / control treatment
Control Group (CO-PA)- In addition to the PA program participants in this group will receive a standard education program including general health education focusing on information on Healthy Ageing delivered via the manual and workshops. There will be three group-workshops in the first 6 months. The first will have a duration of two hours, and the remaining workshops will be of 1-hour duration at 8-weekly intervals. The workshops for the two groups will be held in different buildings to avoid contamination between the two groups.

The control group participants will also receive the Standard Telephone Contact Support during which the volunteer peer-contact (the Physical Activity Liaison) will follow a script and record progress. Over the 6-month intervention period the mentors will make 6 calls at 4-week intervals starting at week 2 then weeks 6, 10, 14, 18 and 22. The control group does not receive any feedback or motivational advice on goal setting or orientation. This control group receives the same contact hours with their peer mentor/PAL than the intervention group.

Adherence to the prescribed program will be assessed from self reported PA diaries. The PALs will also be monitoring adherence and keeping records via the telephone calls. The type, frequency, duration and intensity of the PA will be determined from these records. Adherence will be calculated as the number of minutes of moderate activity completed relative to the prescribed 150 minutes/week expressed as a percentage.

Instead of a Peer Mentor, the control group participants receive a Physical Activity Liaison - community volunteers who will be recruited and randomised to either be a peer goal-mentor for the intervention group or this Physical Activity Liaison for the Control group. The PALs will attend a 2-hour training course on how to conduct the standard telephone contact.
Control group
Active

Outcomes
Primary outcome [1] 290696 0
The primary outcome will be the change in PA at follow-up as measured by the pedometer in steps/day.
Timepoint [1] 290696 0
6 and 12 months following randomisation
Secondary outcome [1] 305055 0
Goal-orientation and functional goals. Measured by the BGSI.
Timepoint [1] 305055 0
6 and 12 months following randomisation
Secondary outcome [2] 305056 0
Quality of life - measured by the SF-36.
Timepoint [2] 305056 0
6 and 12 months following randomisation
Secondary outcome [3] 305057 0
Self-efficacy of mentors - as measured by the Self-efficacy scale in mentors.
Timepoint [3] 305057 0
6 and 12 months following randomisation
Secondary outcome [4] 305104 0
Cognitive and Clinical Assessments: Mini-Mental State Examination, The Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) neuropsychological assessment battery, Alzheimer’s Disease Assessment Scale 13 – cognitive section (ADAS-cog 13), Clinical Dementia Rating Scale (CDR), Behaviour Rating Inventory of Executive Function – Adult Version (BRIEF-A), Short Form 36 Version 2 (SF-36v2), Memory Complaint Questionnaire (MAC-Q), Hospital Anxiety and Depression Scale (HADS), Delis-Kaplan Executive Function System (D-KEFS) - verbal fluency, Stroop Task, Digit Symbol Coding, WAIS III Digit Span (forward and backwards), Cambridge Contextual Reading Test, NEO-PI.
Timepoint [4] 305104 0
6 & 12 months following randomisation and a reduced test battery at follow-up (2-4 years post-intervention)
Secondary outcome [5] 305143 0
Adherence to the prescribed PA program - assessed from self reported PA diaries.
Timepoint [5] 305143 0
6 and 12 months following randomisation
Secondary outcome [6] 305188 0
Functional Fitness Assessments: Grip strength, Step Test, Sit-to-Stand Test, Timed Up and Go Test, 6-minute Walk Test.
Timepoint [6] 305188 0
6 & 12 months following randomisation and a reduced test battery at follow-up (2-4 years post-intervention)
Secondary outcome [7] 305189 0
Health assessments: Height, Body weight, BMI, Girth, Blood pressure.
Timepoint [7] 305189 0
6 & 12 months following randomisation and a reduced assessment at follow-up (2-4 years post-intervention)

Eligibility
Key inclusion criteria
FOR PARTICIPANTS
1) aged between 60 and 85 years old at last birthday;
2) community dwelling;
3) fulfils the criteria for Subjective Memory Complainer (SMC) or Mild Cognitive Impairment (MCI).
4) Needs to understand spoken and written English
5) Needs to be able to attend visits to the National Ageing Research Institute (NARI)
6) Inactive (insufficiently active) defined as less than 60 minutes per week of regular moderate intensity leisure physical activity.


FOR VOLUNTEER MENTORS/PHYSICAL ACTIVITY LIAISONS
1) aged 50-85 years
2) meets the PA guidelines of 150 minutes/week of moderate intensity PA
3) Needs to understand spoken and written English
4) Needs to be able to attend visits to the National Ageing Research Institute (NARI)
Minimum age
60 Years
Maximum age
85 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
FOR PARTICIPANTS
1) Telephone Interview for Cognitive Status – Modified (TICS-M) score < 19 (Those scoring lower than this will be excluded due to the likely presence of dementia);
2) baseline Mini-Mental State Examination score (MMSE) < 24;
3) diagnosis of dementia;
4) GDS-15 score > 6 (= no significant depression);
5) unstable or life threatening medical condition;
6) medical condition that contra-indicates moderate PA;
7) non-sedentary lifestyle
8) Body Mass Index (BMI) > 35;
9) severe visual or hearing impairment;
10) history of chronic alcohol abuse within the past five years;
11) unable to attend the follow-up visits.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
FOR PARTICIPANTS
1) telephone screening to initially determine eligibility
2) approval from primary care physician and the project medical team
3) if eligible, baseline assessment
4) randomisation. Allocation is concealed using sealed opaque envelopes and is drawn by an independent person who is "off-site" and not part of the study team.

FOR MENTORS/ PHYSICAL ACTIVITY LIAISONS
1) telephone screening to initially determine eligibility
2) if eligible, baseline assessment
3) randomisation (mentor or physical activity liaison). Allocation is concealed using sealed opaque envelopes and is drawn by an independent person who is "off-site" and not part of the study team.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Generation of Random Numbers for both groups:
A list of consecutive Study IDs will be assigned to either the intervention or control group (in 1:1 ratio). Participants who satisfied the study selection criteria will be assigned the next available ID on this list by an investigator not involved in data collection or intervention. The varying-size blocked random allocation will be computer generated using “ralloc” user-written command implemented in Stata 12 statistical
software
(Ryan P (2000). Random allocation of treatments balanced in blocks: update. Stata Technical Bulletin 54: 49-53).
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
PARTICIPANTS:
- In a previous study (pilot data; unpublished) the response within each subject group was normally distributed with a standard deviation 2174 steps.
- We have also shown that a mean difference of 1200 steps between experimental and control group would have clinical implications.
- Therefore, we will need to study 53 experimental subjects and 53 control subjects.
We have accounted for a 25% attrition rate and loss to follow-up. We also adjusted for the intra-class correlation generated by having one mentor with more than one participant. We calculated the inflation factor 1+r(c-1), in which, on average, each mentor will have 2 participants (c), and we have assumed an intraclass correlation of 0.15 (r), which is considered of medium size. This would require a minimum of 76 participants, which we rounded up to 80 per group.

MENTORS/ PHYSICAL ACTIVITY LIAISONS:
We have previously been successful in attracting over 100 potential mentors. The retention rate for mentors from training to the end of the intervention period in our previous study was 84%. If we train 50 mentors at each site and allowing for a 20% withdrawal rate this will give us at least 40 active volunteers who could be assigned two participants each.

Data Analysis
The efficacy of the intervention will be primarily assessed with an intention-to-treat analysis at the end of the intervention with secondary analysis for the 12-month time point. This effect will be tested as the interaction between the allocation group (intervention and control) and time, on the primary and secondary outcomes. We will apply multilevel regression models (mixed models) given the repeated measures of the dataset.

The baseline value of each outcome will be included in the model as a covariate. In a complementary analysis, we will apply imputation by chained equations to perform an intention-to-treat (ITT) analysis of primary and secondary outcome measures. Alpha will be set at 5% and all statistical tests reported will be two-tailed.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
24/10/2013
Actual
24/10/2013
Date of last participant enrolment
Anticipated
15/08/2019
Actual
Date of last data collection
Anticipated
20/08/2021
Actual
Sample size
Target
160
Accrual to date
52
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment hospital [1] 1585 0
Royal Melbourne Hospital - Royal Park campus - Parkville
Recruitment hospital [2] 1586 0
St Vincent's Hospital (Melbourne) Ltd - Fitzroy
Recruitment postcode(s) [1] 7464 0
3101 - Kew
Recruitment postcode(s) [2] 7465 0
3001 - Melbourne

Funding & Sponsors
Funding source category [1] 288112 0
Government body
Name [1] 288112 0
National Health and Medical Research Council
Country [1] 288112 0
Australia
Primary sponsor type
University
Name
The University of Melbourne
Address
Melbourne Research Office
Level 5, Allan Gilbert Building
The University of Melbourne, VIC
3010
Country
Australia
Secondary sponsor category [1] 286833 0
Other
Name [1] 286833 0
National Ageing Research Institute
Address [1] 286833 0
34-54 Poplar Road
Parkville, VIC
3052
Country [1] 286833 0
Australia
Other collaborator category [1] 277649 0
University
Name [1] 277649 0
University of Western Australia
Address [1] 277649 0
School of Medicine and Pharmacology (Royal Perth Hospital Unit)
GPO Box X2213
Perth. WA 6001
Country [1] 277649 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 290035 0
Melbourne Health
Ethics committee address [1] 290035 0
Ethics committee country [1] 290035 0
Australia
Date submitted for ethics approval [1] 290035 0
Approval date [1] 290035 0
06/05/2013
Ethics approval number [1] 290035 0
MH Project Number: 2013.020
Ethics committee name [2] 290036 0
St Vincent's Hospital Melbourne
Ethics committee address [2] 290036 0
Ethics committee country [2] 290036 0
Australia
Date submitted for ethics approval [2] 290036 0
01/10/2013
Approval date [2] 290036 0
Ethics approval number [2] 290036 0
HREC-A 100/13

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 43598 0
Prof Nicola Lautenschlager
Address 43598 0
Academic Unit for Psychiatry of Old Age
The University of Melbourne
St George's Health Service
283 Cotham Rd
Kew VIC 3101
Country 43598 0
Australia
Phone 43598 0
+61 3 9816 0485
Fax 43598 0
Email 43598 0
[email protected]
Contact person for public queries
Name 43599 0
Jenny Southam
Address 43599 0
Academic Unit for Psychiatry of Old Age, University of Melbourne, RMH-Royal Park Campus, Building 5, Ground Floor, 34-54 Polar Road, Parkville, VIC, 3052
Country 43599 0
Australia
Phone 43599 0
+61 3 83872693
Fax 43599 0
Email 43599 0
[email protected]
Contact person for scientific queries
Name 43600 0
Nicola Lautenschlager
Address 43600 0
Academic Unit for Psychiatry of Old Age, University of Melbourne, RMH-Royal Park Campus, Building 5, Ground Floor, 34-54 Polar Road, Parkville, VIC, 3052
Country 43600 0
Australia
Phone 43600 0
+61 3 83872326
Fax 43600 0
Email 43600 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Participants consented only to their data being used for the INDIGO trial and any data sharing would require new ethics and additional consent. The current researchers will still be actively using the data for several more years.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseA Randomized Controlled Trial on the Effects of a 6-Month Home-Based Physical Activity Program with Individual Goal-Setting and Volunteer Mentors on Physical Activity, Adherence, and Physical Fitness in Inactive Older Adults at Risk of Cognitive Decline: The INDIGO Study.2021https://dx.doi.org/10.3233/JAD-210479
EmbaseFactors Influencing Long-Term Physical Activity Maintenance: A Qualitative Evaluation of a Physical Activity Program for Inactive Older Adults at Risk of Cognitive Decline: The INDIGO Follow-Up Study.2022https://dx.doi.org/10.3233/JAD-220202
N.B. These documents automatically identified may not have been verified by the study sponsor.