Category: Respiratory Diseases

First New Treatment for Asthma Attacks in 50 Years

Photo by Louis Reed on Unsplash

An injection given during some asthma and COPD attacks was shown to be more effective than the current treatment of steroid tablets, reducing the need for further treatment by 30%. The findings, published in The Lancet Respiratory Medicine, could be “game-changing” for millions of people with asthma and COPD around the world, scientists say.

The type of symptom flare-up the injection treats are called ‘eosinophilic exacerbations’ and involve symptoms such as wheezing, coughing and chest tightness due to inflammation resulting from high amounts of eosinophils, a type of white blood cell. Eosinophilic exacerbations make up to 30% of COPD flare-ups and almost 50% of asthma attacks. They can become more frequent as the disease progresses, leading to irreversible lung damage in some cases.

Treatment at the point of an exacerbation for this type of asthma has barely changed for over fifty years, with steroid drugs being the mainstay of medication. Steroids such as prednisolone can reduce inflammation in the lungs but have severe side-effects such as diabetes and osteoporosis. Furthermore, many patients ‘fail’ treatment and need repeated courses of steroids, re-hospitalisation or die within 90 days.

Results from the phase two clinical trial ABRA study, led by scientists from King’s College London and sponsored by the University of Oxford, show a drug already available can be re-purposed in emergency settings to reduce the need for further treatment and hospitalisations. The multi-centre trial was conducted at Oxford University Hospitals NHS Foundation Trust and Guy’s and St Thomas’ NHS Foundation Trust.

Benralizamab is a monoclonal antibody which targets eosinophils to reduce lung inflammation. It is currently used for the treatment of severe asthma. The ABRA trial has found a single dose can be more effective when injected at the point of exacerbation compared to steroid tablets.

The study investigators randomised people at high risk of an asthma or COPD attack into three groups, one receiving benralizumab injection and dummy tablets, one receiving standard of care (prednisolone 30mg daily for five days) and dummy injection and the third group receiving both benralizumab injection and standard of care. As a double-blind, double-dummy, active-comparator placebo-controlled trial, neither the people in the study, or the study investigators knew which study arm or treatment they were given.

After 28 days, respiratory symptoms of cough, wheeze, breathlessness and sputum were found to be better with benralizumab. After 90 days, there were four times fewer people in the benralizumab group that failed treatment compared to standard of care with prednisolone.

Treatment with the benralizumab injection took longer to fail, meaning fewer episodes to see a doctor or go to hospital. Quality of life also improved for people with asthma and COPD.

This could be a game-changer for people with asthma and COPD. Treatment for asthma and COPD exacerbations have not changed in fifty years despite causing 3.8 million deaths worldwide a year combined.

– Lead investigator of the trial Professor Mona Bafadhel from King’s Centre for Lung Health

She added: “Benralizumab is a safe and effective drug already used to manage severe asthma. We’ve used the drug in a different way – at the point of an exacerbation – to show that it’s more effective than steroid tablets which is the only treatment currently available. The big advance in the ABRA study is the finding that targeted therapy works in asthma and COPD attacks. Instead of giving everyone the same treatment, we found targeting the highest risk patients with very targeted treatment, with the right level of inflammation was much better than guessing what treatment they needed.”

The benralizumab injection was administered by healthcare professionals in the study but can be potentially administered in the GP practice or in the Emergency Department. Benralizumab was safe in the study and similar in safety to many past studies.

Professor Mona Bafadhel said, “We hope these pivotal studies will change how asthma and COPD exacerbations are treated for the future, ultimately improving the health for over a billion people living with asthma and COPD across the world.”

Source: King’s College London

The New RSV Vaccine is Effective – But Uptake is Low

Creative artwork featuring 3D renderings of respiratory syncytial virus (RSV)—a common contagious virus that infects the human respiratory tract – colourised as follows: (the viral envelope is purple, G- glycoproteins are light blue, and F-glycoproteins are orange). F-glycoproteins allow the virus to fuse with and infect human cells. Credit: NIAID/NIH

Since their introduction last year, researchers have been monitoring the real-world impact of the new respiratory syncytial virus (RSV) vaccines. In a recent commentary in The Lancet, Angela Branche, MD, an infectious diseases researcher at the University of Rochester Medical Center (URMC), details what has been learned during the vaccine’s first season.

“The evidence is clear; individuals should get vaccinated if they have conditions that place them at risk for severe disease. For older adults and those with chronic conditions, RSV should be considered as serious as the flu, and they should get vaccinated,” said Branche.

RSV is a significant cause of severe respiratory illness among older adults, especially those with underlying health conditions. Worldwide, RSV causes millions of infections, hundreds of thousands of hospitalisations, and tens of thousands of deaths annually in adults aged 60 and older. Older people with RSV are at higher risk of severe illness compared to those with influenza or COVID.

In 2023, the FDA approved three RSV vaccines for older adults. Studies have shown these vaccines to be effective, with the Pfizer, GSK, and Moderna vaccines preventing RSV pneumonia and bronchitis in more than 80% of participants.

A recent study published in The Lancet assessed the effectiveness of RSV vaccines using data from a large electronic health record network involving the Centers for Disease Control and Prevention (CDC) and multiple US healthcare systems. The study found that RSV vaccines were 80% effective in preventing hospitalisation, ICU admission, and death among adults aged 60 and older. Vaccine effectiveness was consistent across age groups, including those 75 and older, and among immunocompromised individuals. The study did not find evidence of waning vaccine protection within the season.

The uptake of the RSV vaccine in the 2023-2024 winter season was low, however. An estimated 24% of US adults aged 60 years and older received the vaccine, compared to influenza vaccination rates, which approach 50% each year for the same group. “Providers were not sure how to apply the shared clinical decision-making recommendations in the first season, and there remains a general lack of knowledge among the medical community and the public on what constitutes a risk for severe disease and who needs to be protected,” said Branche.

Based on these findings, the US Advisory Committee on Immunization Practices (ACIP), a group of medical and public health experts that advises the CDC, updated guidelines in June 2024 to recommend RSV vaccination for all adults aged 75 and older, those 60 and older in long-term care facilities or with chronic and high-risk health conditions.

“This new data enabled the ACIP to make more definitive recommendations, which will build public confidence in the effectiveness of these vaccines and make implementation a lot easier for providers and pharmacies,” said Branche.

New research shows that vaccines that target multiple strains of the RSV virus, called bivalent vaccines, may provide longer protection. URMC infectious disease experts helped lead an international study of a bivalent RSV vaccine developed by Pfizer, the results of which were recently detailed in the New England Journal of Medicine. The vaccine effectively prevented severe RSV-related lower respiratory tract illnesses over two RSV seasons, with > 80% overall efficacy. The experimental vaccine was particularly effective in individuals aged 60-79.

Source: University of Rochester Medical Center

TB Alters Liver Metabolism and could Promote Diabetes, Study Shows

Tuberculosis bacteria. Credit: CDC

Scientists from the University of Leicester have discovered that tuberculosis disrupts glucose metabolism in the body. The findings, which have now been published in PLoSPathogens complement the understanding that diabetes worsens the symptoms of tuberculosis. Importantly, they now say, undiagnosed tuberculosis could be pushing vulnerable patients towards metabolic disease such as diabetes.

Tuberculosis (TB) remains one of the most devastating infectious diseases worldwide, killing over 4,000 people every day. Prevention through the development of improved vaccines remains a priority for the World Health Organisation. Currently only one vaccine exists for TB and this is predominantly given to infants and young children to help protect them from severe forms of infection. 

Scientists at the University are researching tuberculosis in the hope of creating improved vaccines and are specifically looking at ways in which undiagnosed and subclinical infection can impact health. This new discovery, they say, could pave the way to define the molecular pathways by which the immune response changes liver metabolism, thereby allowing for the creation of targeted interventions. 

Professor Andrea Cooper from the University’s Leicester Tuberculosis Research Group (LTBRG), is among the authors on the paper.

She said: “Our paper changes the focus from diabetes making TB worse to the possibility that late diagnosis of TB can contribute to disruption of glucose metabolism, insulin resistance and therefore can promote progress towards diabetes in those that are susceptible. 

“As diabetes compromises drug treatment, our paper also supports the idea that metabolic screening should be involved in any drug or vaccine trials.”

The study first used laboratory models of pulmonary TB to examine the changes happening within the liver during the early stages of infection. It found that an immune response was triggered within the liver cells and glucose metabolism was altered. 

First author Dr Mrinal Das then reanalysed published metabolic data from humans, where he found that liver glucose metabolism was also disrupted when people progressed to TB from latent infection.

Professor Cooper added: “Our future aim is to define the molecular pathways by which the immune response is changing liver metabolism, allowing us to potentially create targeted interventions.

 “We will also be investigating how latent TB (which is infection with the bacterial agent of TB without significant symptoms) might be impacting metabolic health in humans.” 

Source: University of Leicester

Elevated NK Cells Found in Children with Severe RSV

Photo by Andrea Piacquadio on Unsplash

Respiratory syncytial virus (RSV) is the leading cause of hospitalisation in young children due to respiratory complications such as bronchiolitis and pneumonia. Yet little is understood about why some children develop only mild symptoms while others develop severe disease.

To better understand what happens in these cases, clinician-scientists from Brigham and Women’s Hospital, and Boston Children’s Hospital analysed samples from patients’ airways and blood, finding distinct changes in children with severe cases of RSV, including an increase in the number of natural killer (NK) cells in their airways.

The descriptive study, which focuses on understanding the underpinnings of severe disease, may help to lay groundwork for identifying new targets for future treatments. Results are published in Science Translational Medicine.

“As a physician, I help to care for children who have the most severe symptoms, and as a researcher, I’m driven to understand why they become so sick,” said corresponding author Melody G. Duvall, MD, PhD, of the Division of Pulmonary and Critical Care Medicine at Brigham and Women’s Hospital (BWH) and the Division of Critical Care Medicine at Boston Children’s Hospital. “NK cells are important first responders during viral infection – but they can also contribute to lung inflammation. Interestingly, our findings fit with data from some studies in COVID-19, which reported that patients with the most severe symptoms also had increased NK cells in their airways. Together with previous studies, our data link NK cells with serious viral illness, suggesting that these cellular pathways merit additional investigation.”

Duvall and colleagues, including lead author Roisin B. Reilly of the Division of Pulmonary and Critical Care Medicine at BWH, looked at samples from 47 children critically ill with RSV, analysing immune cells found in their airways and peripheral blood. Compared to uninfected children, those with severe illness had elevated levels of NK cells in their airways and decreased NK cells in their blood. In addition, they found that the cells themselves were altered, both in appearance and in their ability to perform their immunological function of killing diseased cells.

Duvall and co-authors have previously described a post-pandemic surge in paediatric RSV infections. While clinicians can only provide supportive care to the most severely sick children, vaccines to prevent RSV are now available for children 19 months and younger, adults 60 years and over, and people who are pregnant.

Source: Brigham and Women’s Hospital

Promising TB Therapy for Patients with HIV Safe with Antiretrovirals

Tuberculosis bacteria. Credit: CDC

A therapy showing promise to help control tuberculosis (TB) does not interfere with combined antiretroviral therapy (cART), according to research by Texas Biomedical Research Institute (Texas Biomed) which was recently published in JCI Insight.

“This is an important hurdle that this host-directed therapy had to clear in order to help patients battling both HIV and TB,” said study leader Professor Smriti Mehra, PhD of Texas Biomed.

TB is responsible for more than 1.3 million deaths worldwide every year. Dr. Mehra and her team have been investigating a therapy currently used in cancer as a potential treatment for patients with drug-resistant TB and/or comorbid HIV. While many cases of TB can be controlled with months of antibiotics, the infection can return in people who are immunocompromised as a result of HIV. Now that cART is so effective at controlling HIV, a resurging TB infection can often be deadly to those individuals.

Dr Mehra is studying a host-directed therapy that blocks or inhibits an immune system protein naturally found in the body. The protein, called IDO (short for Indoleamine-2,3-dioxygenase), normally suppresses the immune system, preventing it from causing excessive inflammation and organ damage. Inhibiting IDO for short intervals of time has led to more successful cancer treatments. Dr. Mehra’s team has previously shown the same approach improves control of TB in conjunction with antibiotics.

This current study in nonhuman primates with both TB and simian immunodeficiency virus, the nonhuman primate version of HIV, showed the IDO inhibitor does not interfere with cART.  

Researchers compare the impacts of cART by itself versus cART plus the IDO inhibitor in lung tissue of nonhuman primates with both TB and SIV. Left: Following just cART, significantly more IDO is detected in pink. Right: With the IDO inhibitor and cART, immune cells recruited to fight bacteria are observed inside the granuloma, a hallmark structure of TB. Specifically, CD4+ T cells are in green and CD68 proteins expressed by macrophages are in red.

“There was no increase in viral load in animals given cART and the IDO inhibitor, compared with animals only given cART, proving the inhibitor is safe to give to patients with HIV,” Dr. Mehra said.

Now that the researchers have shown the inhibitor works well in conjunction with TB antibiotics and with cART separately, they plan to study how it performs when given in conjunction with both antibiotics and cART together. This treatment regimen is standard for patients with both HIV and active TB. Dr. Mehra said that longer-term studies are also needed to confirm there are no unintended side effects.

The IDO inhibitor is already FDA-approved for use in patients with cancer, which shortens the path to potential approval for patients with TB/HIV when compared with developing a brand-new drug.

Source: Texas Biomedical Research Institute

Herbal Compound Found to Kill TB in the Inactive State

Mycobacterium tuberculosis drug susceptibility test. Photo by CDC on Unsplash

A compound found in African wormwood – a plant used medicinally for thousands of years to treat many types of illness – could be effective against tuberculosis, according to a new study available online in the Journal of Ethnopharmacology.

The team, co-led by Penn State researchers, found that the chemical compound, an O-methylflavone, can kill Mycobacterium tuberculosis, or Mtb, that causes tuberculosis in both its active state and its slower, hypoxic state, which the mycobacteria enters when it is stressed.

Bacteria in this state are much harder to destroy and make infections more difficult to clear, according to co-corresponding author Joshua Kellogg, assistant professor of veterinary and biomedical sciences in the College of Agricultural Sciences.

While the findings are preliminary, Kellogg said the work is a promising first step in finding new therapies against tuberculosis.

“Now that we’ve isolated this compound, we can move forward with examining and experimenting with its structure to see if we can improve its activity and make it even more effective against tuberculosis,” he said. “We’re also still studying the plant itself to see if we can identify additional molecules that might be able to kill this mycobacterium.”

Tuberculosis is one of the world’s leading killers among infectious diseases, according to the Centers for Disease Control and Prevention. There are about 10 million cases a year globally, with approximately 1.5 million of those being fatal.

While effective therapies exist for TB, the researchers said there are several factors that make the disease difficult to treat. A standard course of antibiotics lasts six months, and if a patient contracts a drug-resistant strain of the bacteria, it stretches to two years, making treatment costly and time consuming.

Additionally, the bacteria can take two forms in the body, including one that is significantly harder to kill.

“There’s a ‘normal’ microbial bacterial form, in which it’s replicating and growing, but when it gets stressed – when drugs or the immune system is attacking it – it goes into a pseudo-hibernation state, where it shuts down a lot of its cellular processes until it perceives that the threat has passed,” Kellogg said. “This makes it really hard to kill those hibernating cells, so we were really keen to look at potential new chemicals or molecules that are capable of attacking this hibernation state.”

Multiple species of the Artemisia plant have been used in traditional medicine for centuries, the researchers said, including African wormwood, which has been used to treat cough and fever. Recent studies in Africa have suggested that the plant also has clinical benefits in treating TB.

“When we look at the raw plant extract that has hundreds of molecules in it, it’s pretty good at killing TB,” Kellogg said. “Our question was: There seems to be something in the plant that’s really effective – what is it?”

For their study, the researchers took raw extract of the African wormwood plant and separated it into “fractions” – versions of the extract that have been separated into simpler chemical profiles. They then tested each of the fractions against Mtb, noting whether they were effective or ineffective against the bacteria. At the same time, they created a chemical profile of all of the tested fractions.

“We also used machine learning to model how the changes in chemistry correlated with the changes in activity that we saw,” Kellogg said. “This allowed us to narrow our focus to two fractions that were really active.”

From these, the researchers identified and tested a compound that effectively killed the bacteria in the pathogen’s active and inactive states, which the researchers said is significant and rare to see in TB treatments. Further testing in a human cell model showed that it had minimal toxicity.

Kellogg said the findings have the potential to open new avenues for developing new, improved therapeutics.

“While the potency of this compound is too low to use directly as an anti-Mtb treatment, it may still be able to serve as the foundation for designing more potent drugs,” he said. “Furthermore, there appear to be other, similar chemicals in African wormwood that may also have the same type of properties.”

The researchers said that in the future, more studies are needed to continue exploring the potential for using African wormwood for treating TB.

Source: Penn State

New Images of RSV may Expose Weak Points in the Stubborn Virus

Photo by Andrea Piacquadio on Pexels

The complex shape of respiratory syncytial virus is one hurdle limiting the development of treatments for an infection that leads to hospitalisation or worse. New images of the virus published in Nature from researchers at the University of Wisconsin–Madison may hold the key to preventing or slowing RSV infections.

RSV is of greatest concern in young children, the elderly and adults at high risk for respiratory complications. Yet unlike the flu and other common, communicable respiratory illnesses that annually sweep through schools, there are few options for fighting RSV. In the US, prophylactic treatments are available for young children, and existing vaccines are approved only for pregnant women and the elderly.

The virus’s structure, which consists of tiny, bending filaments, have eluded researchers. This has made it difficult to identify key drug targets, including viral components that are conserved across related viruses.

RSV F proteins, shown in this image created by University of Wisconsin–Madison researchers using a technique called cryo-electron tomography, may make RSV more potent by keeping it from infecting cells prematurely. Image by Wright Lab, UW–Madison

“There are a number of viruses related to RSV that are also significant human pathogens, including measles,” says Elizabeth Wright, a UW–Madison biochemistry professor. “What we know about related viruses gives us clues about RSV protein structures, but to identify drug targets we need a closer look at RSV proteins that are intimately associated with the membranes of host cells.”

Using an imaging technique called cryo-electron tomography, Wright and her team have now revealed details of molecules and structures essential to RSV’s form and function. They published their findings recently in Nature.

Cryo-ET freezes viral particles or other molecules at ultracold temperatures, stopping biological processes in action. This allows researchers to examine the structures of organisms, cells and organelles, and viruses and capture small-scale images of structures frozen in time. Flash-freeze many RSV particles, and cryo-ET imaging will capture (nearly) all the virus’s possible configurations from many different angles. These 2D images are combined to produce a representation of the virus’s 3D structures at high resolutions – even at the level of individual atoms.

Wright’s recent study produced high-resolution images detailing the structure of two RSV proteins, RSV M protein and RSV F protein, that are crucial to the interaction between the virus and the host cell membrane. Both proteins are also present in related viruses.

RSV M protein interacts with host cell membranes, holding together the virus’s filamentous structure and coordinating viral components and other proteins – including RSV F proteins. RSV F proteins sit on the viral surface, ready to engage with host cell receptors and regulate the virus’s fusion and entry into the host cell. The scientists’ images reveal that in RSV, two F proteins come together to form a more stable unit. Wright says that this association may prevent the F proteins from prematurely infecting the host cell.

“Our primary findings reveal structural details that allow us to better understand not only how the protein regulates assembly of viral particles, but also the coordination of proteins that enable the virus to be infectious,” says Wright.

The scientists believe that F protein pairs may be a key to destabilising the virus before it is ready to infect its next host, making pairs of F proteins a possible target for future drug development. They will continue to explore how RSV proteins interact with each other to cause infection.

Source: University of Wisconsin-Madison

Signs of Developing Asthma are Evident in the First Year of Life

Respiratory tract. Credit: Scientific Animations CC4.0

What factors lead to chronic respiratory disease? Researchers investigated this question using health data from about 780 infants. Their analysis, published in The Lancet Digital Health, shows that children’s risk of developing asthma later in life can be more reliably predicted by observing the dynamic development of symptoms during the first year of life.

Genetic predisposition, passive smoking, high levels of air pollution and infections are only a few of the risk factors for asthma. Each factor has only a small influence on its own. It is their interplay that makes asthma more likely, according to the hypothesis of an international research committee, of which Professor Urs Frey of the University of Basel and the University Children’s Hospital Basel is a member.

Together with Dr Uri Nahum from his team and international colleagues, Frey investigated how the interaction of these factors during the course of the first year of life affected children’s developing respiratory systems. The analysis was based on health data from two cohorts, amounting to around 780 healthy infants born in various European countries.

A new way of looking at chronic illness

For both cohorts the researchers calculated the network of interactions between a range of known risk factors for every week of each child’s life, and then compared these with the appearance of symptoms such as coughing or wheezing. “Observing this interaction of risk factors in the context of dynamic development over time is a new way of looking at chronic illnesses,” underlines Frey. It is a case of watching the developing lungs adapting to their environment.

And it was exactly this, the adaptation of the lungs, that differentiated the group of children who developed asthma at between two and six years of age from those who had not developed it by the time they started school (generally at six years old in Switzerland). “It’s a nice, practical example of the value of digital health data, which were first quantified mathematically using these kinds of dynamic network analyses,” says Frey.

The findings cannot yet be used for early diagnosis in individual children. However, according to Frey: “With greater amounts of data and machine learning, it would certainly be conceivable to calculate a risk profile for individual children in the future.” Nowadays, digital health data is relatively easy to collect with the help of smartphone apps.

Source: University of Basel

Higher Odds of Miscarriage, Needing Fertility Treatment for Women with Asthma

Credit: Pixabay CC0

Women who are being treated for asthma are more likely to miscarry and need fertility treatment to get pregnant, according to a large study presented at the European Respiratory Society (ERS) Congress in Vienna, Austria. The study also suggests that most women with asthma are able to have babies.

The study was presented by Dr Anne Vejen Hansen from the department of respiratory medicine at Copenhagen University Hospital, Denmark.

She said: “Asthma is common in women of reproductive age. Previous studies have shown that it takes women with asthma longer to get pregnant than those without asthma when undergoing fertility treatment, and that asthmatic women who succeed in getting pregnant have more often had fertility treatment than non-asthmatic women. But most existing studies are on women who have actually got pregnant, so we wanted to examine fertility outcomes on a national scale, to also include those that might not become pregnant at all.”

The team analysed reproductive outcomes for all Danish women born from 1976 to 1999, following them from 1994 to 2017. In total, 769,880 women were included and followed; anyone who took anti-asthma medication on a regular basis was classified as asthmatic.

They found that women with asthma experienced a higher degree of foetal loss compared to women without asthma (17.0% vs. 15.7%) and more use of fertility treatment (5.6% vs. 5.0%). However, the proportion who subsequently gave birth was 77% in women with and without asthma, suggesting that asthma does not seem to affect the number of live births.

Dr Vejen Hansen said: “We found that women fulfilling the definition of asthma had a higher rate of foetal loss and an increased use of fertility treatment. The more severe the asthma and the more flare ups the women experienced, the more likely they were to need fertility treatment. Why this is, is not clear. It might be related to systemic inflammation throughout the body, including women’s reproductive organs.

“But the numbers also show that these same women who redeem asthma medication still have as many live births in the end as women who don’t. This suggests that most women with asthma probably do manage to become pregnant and have babies in the end.

“We also plan to investigate the possible effect of male asthma on fertility, and, therefore, have another similar registry-based study in the pipeline.”

Professor Lena Uller is Chair of the ERS group on Airway Pharmacology and Treatment and Head of the Respiratory Immunopharmacology research group at Lund University, Sweden, and was not involved in the research. She said: “It’s reassuring that women seem to have the same live birth rate regardless of their asthma. However, the results also indicate that women with asthma should take into consideration potential reproductive challenges in their family planning. If women with asthma are worried about their fertility, they should speak to their doctor.

“The results of this study also underscore the importance of managing asthma in reproductive-aged women. The fact that the more severe the asthma, the more the problems with fertility, suggests that uncontrolled asthma is the problem and we should be helping women to get their asthma under control.”

Source: European Respiratory Society

24hrs Oxygen Therapy for Hypoxaemia no Better than 15hrs

Photo by Samuel Ramos on Unsplash

There were no differences in quality of life, symptoms, hospital admissions or mortality between a group of patients with pulmonary disease and low oxygen levels in the blood that received oxygen therapy at home for 24 hours a day, and a group that received the same therapy for 15 hours a day, according to a study in the New England Journal of Medicine.

“This has considerable significance for patients with chronic obstructive pulmonary disease and other pulmonary diseases who are undergoing long-term oxygen therapy at home,” says study leader Magnus Ekström of Lund University.

Every year, there are about a million patients in the US alone with severe sub-optimal oxygen levels who begin oxygen therapy at home. The patient must wear a nasal oxygen mask 24 hours a day, which is often felt to be restrictive and burdensome. In addition, the gas is cold and dry, which may cause problems such as dryness, ulcers and inflammation of the airways. Using the equipment may also be perceived as stigmatising by patients.

The aim of the therapy is to prolong life, but its application differs and the scientific evidence for the therapy’s efficacy has been inadequate. 

In a randomised, controlled large multicentre study, the researchers have now examined the effect of different durations of oxygen therapy on important health outcomes. A total of 241 patients with chronic and severely low oxygen levels in the blood from 20 different clinics in Sweden were randomised to receive oxygen therapy for either 24 hours a day or 15 hours a day. The patients were followed for one year, and all completed the study. There was a high level of compliance with the prescribed daily therapy duration.  

“There were no differences between the groups regarding hospital admission or the risk of dying. And again, when we compare self-reported quality of life and physical activity, symptoms and fatigue between the groups, we see no differences or indication of advantages if oxygen is used for more than 15 hours a day,” says Magnus Ekström, researcher in respiratory and palliative medicine at Lund University.

 The results differ from previous studies conducted in the 1970s, which suggested that therapy for 24 hours a day could increase the survival rate. 

“The older studies were small and only included patients with chronic obstructive pulmonary disease, not least because it is difficult to recruit such seriously ill individuals for a randomised study. Also, the patients included in the older studies differ from those who start oxygen therapy at home nowadays. The strength of this study is  that we have been able to include twice as many patients, and that it represents the reality nowadays in which many of those receiving oxygen therapy at home are older, also have cardiovascular diseases and are women,” says Josefin Sundh, adjunct senior lecturer at Örebro University and pulmonologist at the University Hospital in Örebro, who was co-leader of the study.

“The group treated with oxygen 15 hours a day received this during the night when, in general, oxygenation is poorer. The results show that it seems to be safe for this type of patient to be without oxygen for quite a large part of the day. This is important as it may reduce the side effects of the therapy and mean that the patients can adapt it more to their everyday life,” says Magnus Ekström.

The researchers based the study on data from Swedevox, the Swedish National Registry for Respiratory Failure. 

The researchers are now moving on to examine whether therapy using a high flow rate of warmed-up, more humidified oxygen at night can improve prognoses and patient well-being.

Source: Lund University