Last year saw a plethora of COPD research hit the journals but what were the significant findings that could change practice as we know it? In a ‘year in review’ session international expert Dr Craig Hersh from the Brigham and Women’s Hospital in Boston gave #ATS2016 delegates here in San Francisco his take on the highlights.
- Novel endobronchial devices
Bronchoscopic lung-volume reduction in patients with emphysema using one-way endobronchial valves has achieved some success, providing an alternative to surgery, but might be more effective when patients do not have collateral interlobar ventilation, Dr Hersh told the meeting.
The Dutch STELVIO study used a one-way valve that aimed to collapse the targeted lobe as air was expelled.
Compared to patients receiving usual care, those with the valves had better FEV1 and FVC at six months, as well as a 74 metre improvement in 6-minute walk distance.
The cost of these gains was a higher rate of adverse events, including pneumothorax in six of 34 treated patients, of whom five needed a chest tube inserted. Twelve patients required repeat bronchoscopies, and the valves had to be removed in seven.
“The study screened 680 patients to enrol 68, suggesting that only a minority of those with severe COPD will be eligible,” Dr Hersh said.
The larger LIBERATE study of the technique is now in progress.
- Identification of early disease in smokers
Another significant study published in the last year suggested that lung disease and respiratory impairments are common in smokers who do not have COPD according to conventional spirometric criteria.
Analysis of 4,388 smokers with normal spirometry enrolled in the COPDGene study found that 54% had at least one respiratory problem such as chronic bronchitis, dyspnoea, reduced exercise tolerance or evidence of emphysema or gas trapping on CT.
“As chest CT scans become more widespread for lung cancer screening, a substantial percentage of current and former smokers will be found to have emphysema and/or airway abnormalities,” Dr Hersh said.
- More accurate phenotyping of patient subtypes
The ECLIPSE study used the statistical technique of cluster analysis to define COPD subtypes in more than 2,000 COPD patients.
Five main types emerged, including ‘moderate quasi-stable’ patients who had the best lung function and lowest exacerbation rate, the emphysematous exacerbators, those with functional emphysema but low rates of infection and exacerbation, and the ‘inflamed comorbids’ who had multiple comorbidities, systemic inflammation and the worst survival.
Each of these subtypes has features that could potentially be use to guide targeted treatment, Dr Hersh told delegates.
Unfortunately, though, more than half the patients fell into a heterogeneous ‘mixed’ group, offering little to physicians aiming for a ‘precision medicine’ approach.
Although the analysis commenced by looking at 41 clinical and laboratory variables, there were five simple features that identified most patents within each subgroup: FEV1, body mass index, dyspnoea, white blood cell count, and fibrinogen level.