Digital technology for early identification of chest infections in people with cystic fibrosis

Review question

Can digital technology identify chest infections in people with cystic fibrosis (CF) earlier than with standard care and how does this affect clinical outcomes?

What is cystic fibrosis?

CF is a life-limiting condition affecting several body organs, especially the lungs. Chest infections can worsen the damage in the lungs of people with CF. Identifying chest infections early and treating them quickly is very important. Digital technology, such as smartphone applications (apps) and devices to measure breathing to track symptoms may allow us to identify chest infections earlier in people with CF and start treatment with antibiotics quicker. 

What did we want to find out?

We want to know if early identification of chest infections can help slow down how quickly the condition of the lungs worsens. 

What did we do?

We searched medical databases for well-designed clinical trials in people with CF. People taking part in the studies had the same chance of being in either the treatment group (who used the digital technology) or the usual care group.

What did we find?

We found three studies with 415 people with CF aged 15 to 41 years. All the treatment groups used a technology to track their breathing problems, two studies also asked their treatment groups to do regular breathing tests with special devices. All studies followed people in their groups for one year.

Key results

The studies that asked people to do regular breathing tests with special devices and track breathing problems were able to identify chest infections earlier than people in the usual care groups. However, at the end of the study, their breathing tests were similar to the groups that did not use digital technology. 

There were few differences between the groups when we looked at how they felt in their day-to-day life (quality of life), the number of hospital visits or costs. People who took part in the studies did not have any serious issues or problems that arose because of the digital technology they were using, but people were generally not very good at providing data regularly, and did find it quite a burden.

What are the limitations of the evidence?

We can only be moderately sure of these results from the studies we found. In all the studies, the people who took part will have known whether they were in the digital intervention group or the standard care group. This may have affected how they behaved, and what they thought of their breathing problems. In two studies, the teams running the study would have also known which group the person belonged to. This might have affected their choice on whether to start antibiotics, and whether to give the antibiotics by drip into a vein in hospital, or if they could take them as tablets or liquid medicine at home. Two studies did not recruit enough people, so we are less certain about how trustworthy those results are. 

Some types of digital technology can detect chest infections sooner. However, when compared to relying on usual care, technology does not seem to change the rate at which the lungs in people with CF worsen over time.

Search date

The evidence is current to 13 October 2022.

Authors' conclusions: 

Pulmonary exacerbations are universally accepted to be detrimental to progression of CF-related lung disease, therefore, it is intuitive that early detection and intervention would help to improve outcomes. Digital technology provides an opportunity to detect physiological and symptomatic changes to identify exacerbations early. 

Our review found that digital technologies based on recording physiological change (spirometry) and symptoms probably allow earlier identification of exacerbations as a group. However, this may not reduce the number of exacerbations warranting IV antibiotics and there is probably no effect on lung function. This may be partly due to inconsistent definitions of pulmonary exacerbations and discrepancy in the management strategies for pulmonary exacerbations. Overall, the intervention may make little or no difference to QoL scores. 

The adherence to and uptake of digital technologies, especially those which include physiological measurements, are not well sustained and the costs of these need to be balanced against the clinical efficacy.

Read the full abstract...

Cystic fibrosis (CF) is a life-limiting genetic condition affecting various organ systems including the gastrointestinal tract, endocrine system and especially the respiratory tract. Pulmonary exacerbations in CF result in increased symptoms, an acceleration in the rate of lung decline and an increased need for treatment. Early detection of infections or clinical worsening provides an opportunity for proactive treatment that may affect clinical outcomes.


To evaluate whether digital technology can effectively predict pulmonary exacerbations to allow earlier intervention and improved health outcomes without increasing the burden of treatment in people with CF.

Search strategy: 

We used standard, extensive Cochrane search methods. We searched the Cochrane Cystic Fibrosis Trials Register and the reference lists of relevant articles and reviews on 13 October 2022. We searched Embase and the clinical trial registries on 3 January 2023.

Selection criteria: 

We included randomised controlled trials (RCTs) or quasi-RCTs in people with CF looking at whether digital technology can effectively predict pulmonary exacerbations to allow earlier intervention and improved health outcomes without increasing the burden of treatment. 

Data collection and analysis: 

We used standard Cochrane methods. Our primary outcomes were 1. pulmonary exacerbations and 2. quality of life (QoL). Our secondary outcomes were 3. lung function, 4. hospitalisations, 5. intravenous (IV) antibiotics, 6. microbiology, 7. cost-effectiveness and 8. adverse events. We used GRADE to assess certainty of evidence.

Main results: 

We included three studies (415 participants) in people with CF aged 15 to 41 years over a 12-month period. One was a multicentre RCT, whilst two were single-centre RCTs. 

The three studies were mostly similar in their risk of bias, having low or unclear risk of selection bias but a high risk of detection bias, due to the unblinded design of these studies. The studies used a variety of digital technologies to monitor symptoms such as a digital symptom diary either with or without home spirometry monitoring. As the trials only included adults and older children, we are not certain that the results would apply to younger children.

One of our primary outcomes was to assess time to detection of pulmonary exacerbation and number of pulmonary exacerbations identified between the intervention and routine care groups. We were largely unable to pool results in a meta-analysis due to the variety of methodologies and ways of reporting data. Two studies noted a shorter time to detection of exacerbations in the intervention group and one of these also reported that the intervention group had a shorter time to first exacerbation (hazard ratio for time to first exacerbation 1.45, 95% confidence interval (CI) 1.09 to 1.93), whilst a further study reported a shorter time to detection of exacerbations in the intervention group requiring oral or IV antibiotics compared to the control group (median: 70 (interquartile range (IQR) 123) days with intervention versus 141 (IQR 140) days with control; P = 0.02). However, all three studies were concordant in finding no probable effect on spirometry in the intervention groups when compared with their routine care groups over a 12-month period. 

We found that there is probably no difference between groups with regard to QoL scores across most domains except for Weight and Body Image, which favoured the usual care group. There is also probably no difference in the number of days of additional IV antibiotics needed or newly detected pathogens.

No studies reported serious adverse events directly linked to the intervention and one study reported their smartphone application was generally well received.