Launched this month, and funded by the National Institute for Health Research (NIHR), a new collaborative research project investigates ways of monitoring people with high eye pressure, a risk factor for glaucoma.
Launched this month, a new, collaborative research project from City, University of London, Queen’s University Belfast, Moorfields Eye Hospital, and others, will investigate how people with elevated eye pressure could benefit from treatment to reduce their risk of developing glaucoma.
Glaucoma is a common eye condition that can lead to loss of vision if not identified and treated early. High intraocular/eye pressure (ocular hypertension) can increase the chance of developing glaucoma, and is usually detected during a visit to an optometrist, with a very quick ‘air puff’ test.
How common is ocular hypertension?
In the UK around 1.3 million adults have ocular hypertension, and while most of these people will not develop glaucoma, others may require treatment to prevent glaucoma from happening.
It is also expected that the number of people with ocular hypertension will increase in the future. Those with the condition are typically monitored through hospital eye services, which can be inconvenient for patients and are costly to the NHS.
Who currently receives treatment for ocular hypertension?
Eye pressure is considered to be high if it is above 21 mmHg. Current guidance in England and Wales recommends treatment if eye pressure is greater than 24 mmHg, but it is not known whether people with mildly elevated eye pressure (22-23 mmHg) may also benefit.
Treatment for patients can involve laser treatment and/or using eye drops on a daily, lifelong basis. However, this was revealed to be 'inconvenient and impractical without knowing if it stops the progression to glaucoma', by patient engagement work performed by the research team.
Having a tool that could help doctors identify those with ocular hypertension at the greatest risk of progressing to glaucoma would both support clinical decision-making, and improve the information that can be given to patients about the status of their condition.
What research has already been done?
While a 'glaucoma risk calculator' called ‘OHTS-EGPS’ had previously been developed from data from two trials, the National Institute for Heath and Care Excellence (NICE) does not recommend this for use within the NHS. This is because the calculator has a high risk of bias and has not been tested in UK patients.
What will the current research project involve?
The current, two-year research project aims to improve the OHTS-EGPS risk calculator and validate it to make it suitable for use within the NHS. It will also investigate the value of treating people with ocular hypertension of 22 or 23 mmHg.
The project involves the review of anonymised NHS electronic medical records of over 23,000 people who have ocular hypertension and have been monitored at eleven hospital eye services across England and Wales.
The researchers will review the results of vision tests from these medical records, called visual field tests, to determine which people developed glaucoma and consequent, significant sight-loss. They will use this knowledge with other relevant medical record data taken from routine hospital visits, with the aim of improving and validating the OHTS-EGPS glaucoma risk calculator.
They will then explore the value to the NHS of using the improved, validated tool for different follow-up intervals of patients, according to their risk of developing glaucoma.
Patient and Public Involvement (PPI)
Patients’ values and experiences regarding management of ocular hypertension will also be explored via interviews, and their preferences will be formally assessed.
This is crucial to understanding how a new risk calculator tool may be best incorporated within NHS standard clinical practice, in order to both optimise the management of people with ocular hypertension and reduce costs related to the management of the condition.
The research team includes experienced clinicians, researchers and PPI members to support the research. The charity, Glaucoma UK, will also provide advice to the team.
The research is funded by a £656,000 National Institute for Health Research ( NIHR) grant, £114,000 of which will be supporting research team members at the Crabb Lab, City, University of London.
Professor David Crabb
David Crabb, Professor of Statistics and Vision Research and lead of the Crabb Lab at City, University of London, commented:
Glaucoma Risk Prediction in ocular hypertension (GRIP): a cohort study using electronic medical records to validate a risk predictor and determine the cost-effectiveness of different monitoring schemes according to risk of conversion to glaucoma
Award type: National Institute of Health Research (NIHR) Health Technology Assessment (HTA).
Award ID: NIHR131808
Read the award abstract and protocol.