Condition category
Circulatory System
Date applied
15/04/2015
Date assigned
29/04/2015
Last edited
24/03/2016
Prospective/Retrospective
Prospectively registered
Overall trial status
Ongoing
Recruitment status
Recruiting

Plain English Summary

Background and study aims
Obesity is a term used to describe somebody who is very overweight, with a lot of body fat. It's a common problem, estimated to affect around one in every four adults and around one in every five children aged 10 to 11 in the UK. People who are obese are at risk of a number of serious and potentially life-threatening conditions, such as high blood pressure. High blood pressure is dangerous because it can have no symptoms, and increases the risk of a heart attack or stroke. It can also cause permanent damage to vital organs, such as the kidney, eye, brain and heart. Normally, high blood pressure can be treated with medications but these medications don’t work very well in obese patients and we’re not sure why. Most information on blood vessel structure comes from blood vessels studied in a laboratory. Here, we are using a technique which allows us to view blood vessels in the patient directly. Eye (retinal) blood vessel analysis is a non-invasive way to measure the structure of small blood vessels in a patient. The aim of this study is to get a better understanding of the differences in small blood vessel structure between obese patients and lean patients.

Who can participate?
Adults with a BMI over 30 or lower than 25.

What does the study involve?
Participants have non-invasive tests to check how well their blood vessels are functioning. Two of these tests are eye tests. There is also a blood test.

What are the possible benefits and risks of participating?
There are no risks or benefits to participating in this study.

Where is the study run from?
Wellcome Trust Clinical Trials Facility, Central Manchester University Hospitals Trust (UK)

When is the study starting and how long is it expected to run for?
June 2015 to January 2017

Who is funding the study?
British Heart Foundation (UK)

Who is the main contact?
Dr A Greenstein (scientific)

Trial website

Contact information

Type

Scientific

Primary contact

Dr Adam Greenstein

ORCID ID

Contact details

Institute of Cardiovascular Sciences
University of Manchester
Core Technology Facility
Grafton Street
Manchester
M13 9PL
United Kingdom

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

V1; 13/4/14

Study information

Scientific title

Identification of cardiovascular changes in obesity using dynamic and static retinal vessel analysis

Acronym

Study hypothesis

Changes in retinal vessel function can be correlated with obesity, blood pressure, pulse wave velocity and blood metabolic markers.

Ethics approval

North West - Greater Manchester South Research Ethics Committee, 29/07/2015 ref: 15/NW/0548

Study design

Single site cohort observation

Primary study design

Observational

Secondary study design

Cohort study

Trial setting

Hospitals

Trial type

Screening

Patient information sheet

Not available in web format, please use contact details to request a participant information sheet.

Condition

Cardiovascular disease associated with obesity

Intervention

1. Blood sampling for measurement of glycated haemoglobin (HbA1C) and cholesterol
2. Imaging of the retinal vessels using a fundal camera to measure response to hypertension
3. Pulse wave velocity to measure perfusion and blood flow in the peripheral circulation

Intervention type

Other

Phase

Drug names

Primary outcome measures

Vascular function measured by degree of response to flicker stimulation, retinal arteriolar-venular ratio (AVR) and blood oxygen saturation.

Secondary outcome measures

Peripheral measurements: blood pressure, pulse wave velocity and blood levels of HbA1c and blood lipids (triglycerides, LDL and HDL cholesterol).

Overall trial start date

01/06/2015

Overall trial end date

31/01/2017

Reason abandoned

Eligibility

Participant inclusion criteria

Patient-participants:
1. Willing and capable to provide consent to participation
2. BMI greater than 30
3. No known ocular diseases
4. No known concurrent clinical problem likely to interfere with participation or completion of the study

Healthy controls:
1. BMI lower that 25
2. No known diabetes
3. No known ocular diseases
4. No known concurrent clinical problem likely to interfere with participation or completion of the study

Participant type

Mixed

Age group

Adult

Gender

Both

Target number of participants

30 healthy lean controls and 30 obese patient-participants

Participant exclusion criteria

1. Under 18 years old
2. Intubated/ventilated patients
3. Unwilling to give consent to participation OR advised by consultee that this would be against the patient’s wishes
4. Smoker
5. If eaten with in an hour of the examination
6. If drank alcohol within an hour of the examination
7. If drank coffee within an hour of the examination
8. If overly hungry
9. Recently treated infection
10. Known ocular diseases
11. Known concurrent clinical problem likely to interfere with participation or completion of the study

Additional exclusion for healthy controls:
1. Diabetes
2. BMI above 25

Recruitment start date

01/06/2015

Recruitment end date

31/01/2017

Locations

Countries of recruitment

United Kingdom

Trial participating centre

Wellcome Trust Clinical Trials Facility, Central Manchester University Hospitals Trust
Oxford Road
Manchester
M13 9WL
United Kingdom

Sponsor information

Organisation

The University of Manchester

Sponsor details

Oxford Road
Manchester
M13 9PT
United Kingdom

Sponsor type

University/education

Website

Funders

Funder type

Charity

Funder name

British Heart Foundation

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

We hope to publish a paper in a peer reviewed journal by January 2017.

Intention to publish date

01/01/2017

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes

24/03/2016: Ethics approval information added.