Respiratory disease kills 1 in 5 people in the UK - more than ischaemic heart disease - and costs the NHS £6 billion pounds per year. Despite this, respiratory disease is a neglected and underfunded area of research. The Oxford Respiratory Trials Unit (ORTU) aims to improve this and is currently conducting research to improve outcomes in these diseases. We are currently doing research to improve the treatments of diseases that affect the membranes around this lung, diseases that impair breathing during sleep, severe smoking related lung damage and work to understand and improve disabling breathlessness.
Malignant pleural effusions, the development of fluid around the lung in people with cancer, are common and cause disabling breathlessness. We are currently conducting 3 trials into this condition with the aim of relieving the breathlessness and reducing time in hospital.
Our previous research into pleural infection proved that a commonly used treatment for this problem was ineffective and caused significant side effects. This has led us to develop new treatments for pleural infection that we hope will improve outcome for the thousands of people affected by this problem each year.
Obstructive sleep apnoea (OSA) is a common disorder affecting around 4% of the middle-aged population. OSA consists of repeated episodes of obstruction of the airway behind the tongue during sleep producing episodic falls in oxygen levels, rises in blood pressure and arousals from sleep. OSA is simple to diagnose and treat.
The association between OSA and cardiovascular disease is not fully understood, but research has shown that during each apnoea a blood pressure surge occurs which may damage blood vessel walls, leading to diseases such as heart attacks and strokes. These surges are removed when OSA is treated.
The vascular consequences of OSA are currently being investigated at the Oxford Sleep Unit. This is through the large MOSAIC trial where we will look into the effects of continuous positive airway pressure (CPAP) on markers of cardiovascular disease. More recently we have expanded the search for OSA and vascular interactions, looking at OSA in diabetes, diabetic eye disease, vascular reactivity, vascular inflammation and abdominal aneurysms.
PREDICT is a randomised controlled trial which is about to commence, this aims to look at the effect of CPAP therapy in those aged over 65. This is an important question as OSA is approximately 10 times more common in this age group, but they tend to be less affected by the effect of oxygen desaturations. The results of this study will have important clinical and health economic consequences.
Dyspnoea, or breathlessness, is a highly disabling and common symptom in patients with respiratory disease. It is the major symptom of chronic obstructive pulmonary disease (COPD), a common condition with narrowing of the air tubes in the lungs, usually caused by smoking. 3 million people in the UK alone are affected, many of whom remain symptomatic even when treatment is optimised. It leads to disabling symptoms of cough, sputum production, shortness of breath, and is often associated with frequent chest infections. Some patients under-breathe, which can lead to low oxygen and high carbon-dioxide levels. In carefully selected patients extra oxygen used for at least 15 hours a day can help, though sometimes this makes under-breathing worse.
A small, portable ventilator worn each night at home during sleep with a mask applied to the nose or nose and mouth can be used to increase breathing and improve oxygen and carbon-dioxide levels. A number of previous studies have suggested this treatment improves oxygen and carbon-dioxide levels, improves sleep, exercise ability and quality of life. It may also reduce the number of chest infections and visits to the GP or hospital. We are about to set-up a study comparing home ventilation plus oxygen for most of the day, with oxygen alone to assess whether this treatment leads to reduced admissions to hospital, frequency of flare-ups of COPD, slowing of progression of COPD, improved quality of life and increased ability to exercise. Patients will be recruited from at least five centres, and followed up for a year.
Other work into COPD involves studying and following up a large group of patients with this condition. This work will involve genetic analysis, detailed studies on lung function and structure and relate this how the patient feels and how their disease progresses. Understanding how COPD affects different people may enable us to tailor specific treatment to the individual.
A further area of interest is the effects of high altitude on the lungs. This research may also be relevant to patients with low iron levels in the blood and we are studying the effects of iron supplementation on blood pressure in the lungs.
Aims of the ORTU
Our aim is to work with doctors across the country to improve the care of patients with respiratory diseases and the quality and quantity of respiratory research in the UK. In this way, we hope to improve the quality of life of the millions of people throughout the world who suffer from respiratory disease.