The changing face of pulmonary hypertension diagnosis: a historical perspective on the influence of diagnostics and biomarkers

Routine Asthma Test More Reliable In Morning And Has Seasonal Effects, Say Doctors

A lung function test used to help diagnose asthma works better in the morning, becoming less reliable throughout the day, Cambridge researchers have found.

Using real world data from 1,600 patients, available through a database created for speeding up research and innovation, the team also found that its reliability differs significantly in winter compared to autumn.

Asthma is a common lung condition that can cause wheezing and shortness of breath, occasionally severe. Around 6.5% of people over six years old in the UK are affected by the condition. Treatments include the use of inhalers or nebulisers to carry medication into the lungs.

The majority of asthma attacks occur at nighttime or early in the morning. Although this may in part be due to cooler nighttime air and exposure to dust mites and allergens, it also suggests that circadian rhythms – our 'body clocks' – likely play a role.

Researchers at the Victor Phillip Dahdaleh Heart and Lung Research Institute, a collaboration between the University of Cambridge and Royal Papworth Hospital NHS Foundation Trust (RPH), wanted to explore whether these circadian rhythms may also have an impact on our ability to diagnose asthma, using routinely performed clinical testing.

Typically, people with suspected asthma will be offered a spirometry test, which involves taking a deep breath in, then breathing out hard and fast for as long as possible into a tube to assess lung function. They will then be administered the drug salbutamol via an inhaler or nebuliser, and shortly afterwards retake the spirometry test.

Salbutamol works by opening up the airways, so a positive test result – that is, a difference in readings between the initial and follow-up spirometry tests – means that the airways must have been narrower or obstructed to begin with, suggesting that the patient could have asthma.

Cambridge University Hospitals NHS Foundation Trust (CUH) has recently set up the Electronic Patient Record Research and Innovation (ERIN) database so that researchers can access patient data in a secure environment to help in their research and speed up improvements in patient care.

Using this resource, the Cambridge team analysed data from 1,600 patients referred to CUH between 2016 and 2023, adjusted for factors such as age, sex, body mass index (BMI), smoking history, and the severity of the initial impairment in lung function.

In findings published today in Thorax, the researchers found that starting at 8.30am, with every hour that passed during the working day, the chances of a positive response to the test – in other words, the patient's lungs responding to treatment, suggesting that they could have asthma – decreased by 8%.

Dr Ben Knox-Brown, Lead Research Respiratory Physiologist at RPH, said: "Given what we know about how the risk of an asthma attack changes between night and day, we expected to find a difference in how people responded to the lung function test, but even so, we were surprised by the size of the effect.

"This has potentially important implications. Doing the test in the morning would give a more reliable representation of a patient's response to the medication than doing it in the afternoon, which is important when confirming a diagnosis such as asthma."

The researchers also discovered that individuals were 33% less likely to have a positive result if tested during autumn when compared to those tested during winter.

Dr Akhilesh Jha, a Medical Research Council Clinician Scientist at the University of Cambridge and Honorary Consultant in Respiratory Medicine at CUH, said that there may be a combination of factors behind this difference.

"Our bodies have natural rhythms – our body clocks," Jha said. "Throughout the day, the levels of different hormones in our bodies go up and down and our immune systems perform differently, for example. Any of these factors might affect how people respond to the lung function test.

"The idea that the time of day, or the season of the year, affects our health and how we respond to treatments is something we're seeing increasing evidence of. We know, for example, that people respond differently to vaccinations depending on whether they're administered in the morning or afternoon. The findings of our study further support this idea and may need to be taken into account when interpreting the results of these commonly performed tests."

Reference:

Knox-Brown B, Kon FC, Sylvester KP, et alEffect of time of day and seasonal variation on bronchodilator responsiveness: the SPIRO-TIMETRY studyThorax Published Online First: 11 March 2025. Doi: 10.1136/thorax-2024-222773

'Game-changing' AI-driven Lung Test Set For GP Surgery Rollout

A test driven by artificial intelligence (AI) is set to be rolled out in GP surgeries to help doctors diagnose a common lung condition faster and more accurately, according to its developers.

The device, known as N-Tidal Diagnose, uses carbon dioxide sensors to measure changes in a patient's lung function with results given in minutes.

It has been hailed as "game-changing" by medics, and is also currently being tested for use on asthma.

N-Tidal Diagnose has been granted regulatory clearance and is CE-marked under EU Medical Device Regulations for the diagnosis of COPD.

It will be rolled out in GP surgeries in England from April 14 with the rest of the UK expected to follow, its developer TidalSense said.

COPD refers to a group of lung conditions which cause breathing problems and includes emphysema and chronic bronchitis.

It is currently diagnosed using spirometry, a lung function test which measures how much air a patient can breathe in and out and how quickly they can exhale.

Appointments, which can last between 30 and 90 minutes, involve a patient inhaling fully and breathing out quickly and forcefully.

N-Tidal uses AI to measure carbon dioxide (CO2) concentration in a patient's normal breathing pattern and can give a diagnosis within five minutes.

Dr Ameera Patel, chief executive of TidalSense, said: "For decades, respiratory diagnostics have lagged behind other areas of medicine, despite lung disease being one of the UK's greatest healthcare challenges.

"The N-Tidal Diagnose device represents the first real breakthrough in COPD diagnosis in several decades, addressing both the needs of the patient and of the health system – and it's designed to be deployed at scale across the NHS.

"Our goal is to make respiratory diagnosis fast, accurate, and accessible to everyone who needs it, at the instant that they present."

It is estimated about 1.2 million people in the UK have COPD, with as many as two million people undiagnosed.

Dr Patel claims the test could help the Government meet its goal of slashing NHS waiting times.

She added: "The NHS is under immense pressure and the Government has laid out ambitious plans to change the way services are delivered.

"Its targets against reducing waiting times and using staff time more efficiently will be easier to meet with the introduction of new tools like N-Tidal Diagnose.

"This simple device can help significantly reduce waiting lists, improve patient experience, deliver accurate diagnoses and ultimately provide a better standard of care for the millions of people in the UK who have COPD."

N-Tidal is also being tested for asthma, with the hopes it will one day be used to diagnose the condition once research trials are complete.

Dr Simon Rudland, a GP in Suffolk, hailed the test as a "game changing".

"COPD is one of the most underdiagnosed and misdiagnosed conditions we see in the NHS, and because spirometry testing can only be carried out by specially trained practitioners, it can lead to sizeable wait lists for diagnosis," he said.

"Having the ability to assess a patient's lung health quickly and accurately with a device that gives near-instant results will be game-changing for respiratory care across both primary and secondary healthcare settings."

AI-powered Test Can Detect Silicosis, Scourge Of Mine Workers, In Minutes

Silicosis is an incurable but entirely preventable lung disease. It has only one cause: breathing in too much silica dust. This is a risk in several industries, including tunnelling, stone masonry and construction.

Just last week, ABC reported that 13 workers from tunnelling projects in Sydney have been diagnosed with silicosis. It's yet another reminder that current diagnostic methods are limited. They often detect the disease only after the lungs already have significant damage.

Our new study, published in the Journal of Breath Research, provides the latest results on a breath test for detecting silicosis

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