Clinical trials

Treating sleep apnoea in patients with mild sleep disordered breathing (MERGE trial)

The therapeutic and economic benefits of continuous positive airway pressure (CPAP) for moderate to severe obstructive sleep apnoea (OSA) syndrome have been established. However the benefits of treating mild OSA are not well understood. Moreover, current healthcare systems across the world vary in their reimbursement for treatment of OSA. 

We aim to assess the efficacy of CPA treatment on energy and vitality in patients with mild Obstructive Sleep Apnea: The Merge Study. Our group will work with industry (ResMed) and the Sleep Respiratory Research Network, set up by Prof Morrell during her previous study of CPAP in older people (PREDICT) to carry out this study.


This study established the therapeutic and economic benefits of CPAP for older people with moderate to severe OSA syndrome. The study was carried out in response to an evidence gap identified by the Health Technology Association.

Results published in The Lancet showed that in older people with OSA syndrome, CPAP reduces sleepiness and is marginally more cost effective over 12 months than is best supportive care alone. On the basis of these results, we recommend that CPAP treatment should be offered routinely to older patients with OSA syndrome.

Autotitrating Ventilators

A home ventilator that can automatically adjust to maintain a pre-set ventilation within safe pre-set boundaries could be advantageous for both patients and clinicians. Our group has worked with industry to compare the new mode of ventilation, intelligent volume-assured pressure support (iVAPS), with standard pressure support ventilation in several clinical settings. iVAPS is as effective as usual ventilation and may even promote adherence to therapy. Results showed that the new ventilators improved patient adherence to treatment.

Pandemic Flu

The group won one of the prestigious NIHR HTA Pandemic Flu grants 2009-10 to examine the infectious risk to patients and healthcare workers by evaluating droplet dissemination around non-invasive ventilation, oxygen delivery systems, nebuliser therapy and physiotherapy. The results show for the first time that non-invasive ventilation and physiotherapy generates large droplets, but not an aerosol, and that oxygen therapy generates neither large droplets nor an aerosol. Mathematical modelling was done jointly with Drs R Dickinson & J Siggers and Prof K Parker, Dept Bioengineering, IC. This work will directly influence NHS infection control guidelines.

Pioneering work in Technology Development

Patient with practionerOur group has formed collaborations with the Imperial College Engineering Faculty as well as working relationships with industry to develop, validate and investigate new healthcare technologies. In line with Department of Health objectives to personalise patient treatment, and to keep patients at home and out of hospital, our projects use innovative practice crossing disciplines to bring new technologies from the bench to the patients.

Pioneering work with our Engineering colleagues at Imperial College has allowed us to carry out trials of novel devices that are able to titrate oxygen therapy to optimally correct hypoxaemia during sleep, on exercise and during acute exacerbations in chronic respiratory failure.  Other collaborations with Imperial engineers have lead to the development of a new electrode that can measure brain activity (EEGs) from a single in-ear sensor. For an explanation of these devices please see our Sleep and Ventilation Research video.

New Developments in intermittent hypoxia and the brain

The impact of sleep apnoea on the brain structure and function is considerable. Our seminal findings, published in 2003 in a rapid access journal, attracted world-wide attention. Our current research programme focuses on the neurological impact of sleep apnoea in older people, where we think sleep apnoea may accelerate cognitive decline. To facilitate this research we have set-up a collaboration with Dr Rosenzweig at Kings College London at the Sleep and Brain Plasticity Centre. Our aim is to identify potential biomarkers that will allow us to target treatment strategies for those people most vulnerable to neural decline. This research programme is funded by the Wellcome Trust and Imperial Biomedical Research Centre.

Growing up on a Ventilator: a learning curve

Professor Anita Simonds has recently been given the prestigious ERS Yernault Lecture Award 2016. Her lecture "Growing up on a ventilator: a learning curve" presented data from our group showing that long term ventilation is associated with an increase in survival in a range of conditions leading to ventilatory failure in children. The resulting increasing numbers of children surviving to adulthood has significant implications for planning transition and adult care facilities.

Sleep Disordered Breathing in heart failure

Based in a specialist Heart and Lung Hospital, our group has also focused on the cardiovascular impact of sleep disordered breathing in patients with heart failure. Patients with heart failure and sleep apnoea experience an increased risk of mortality. Our group lead the recently published international SERVE-HF Trial, which has changed the pre-existing belief that treating sleep-disordered breathing might benefit these patients. Despite effective control of sleep apnoea during adaptive servo- ventilation, there were unexpected results in patients with a reduced ejection fraction; patient outcome was not improved and the risk of cardiovascular death was even increased. Further analysis aims to determine the causes.