Respirology最新文献

Background and objective: The COPD Exacerbation Recognition Tool (CERT) contains five symptoms that may change at the onset of an exacerbation. It was designed to help patients with COPD recognise the onset of an exacerbation and seek medical attention. This study tested its sensitivity and specificity and further examined its properties.

Methods: Stable and exacerbating patients presenting to three tertiary hospitals in China were enrolled. Patients' responses to the CERT were compared with physicians' diagnoses made using GOLD 2021 criteria. The CERT was assessed as recommended, and as a total score, using scores assigned to the degree of change for each of the five symptoms (total score 15). Exploratory factor analysis (EFA) was used to identify the key components of the CERT and potentially reduce the number of items.

Results: Sensitivity and specificity of the original CERT were 92.4% and 72.1%. Using a cut-off value of 6, the score-based CERT had the better sensitivity (94.3%) and specificity (86.9%). Concordance between CERT and physician diagnosis was higher with the scored version (kappa 0.833) versus the original version (kappa 0.666). Using EFA, two components were identified 'cough and sputum' and 'breathlessness and activity limitation' with a cumulative variance of 82.3%.

Conclusion: The original and scored-based CERT both had good sensitivity and specificity, but the score-based version showed better concordance with physician diagnosis. The use of two representative items in a 2-item scored version was also effective in identifying acute exacerbations.

Trial registration: ChiCTR2400090589 registered with https://www.chictr.org.cn.

Background and objective: Fixed CPAP (fCPAP) is the preferred first-line ventilatory therapy in patients with obesity hypoventilation syndrome with severe obstructive sleep apnoea (OHS + sOSA). Auto-titrating CPAP (APAP) is not recommended but has not been systematically evaluated in this population. Our pilot study aimed to provide feasibility data for a larger comparative effectiveness trial to determine whether APAP is non-inferior to fCPAP for improving hypercapnic respiratory failure.

Methods: Participants with OHS + sOSA were randomised to either APAP or fCPAP for 3 months. The primary outcome was the change in PaCO₂. Secondary outcomes included changes in quality of life and cardiovascular biomarkers. A sample size of 82 was needed to demonstrate non-inferiority of APAP compared to fCPAP (assuming a non-inferiority margin of -2.5 mmHg). To assess feasibility we aimed to recruit up to 44 participants in this pilot trial.

Results: Twenty-eight of 84 screened participants were randomised (Mean ± SD: Age 55 ± 12.5 years, BMI 54 ± 9.9 kg m^-2, PaCO₂ 49 ± 2.6 mmHg, AHI 88 ± 31 events/h) to APAP (n = 15) or fCPAP (n = 13). Mean adherence exceeded 4 h in both groups; however 25% of randomised participants did not complete the trial. Both treatments reduced PaCO₂ (fCPAP: -5.7 ± 1.6 mmHg, APAP: -4.1 ± 2.8 mmHg). Test of non-inferiority for APAP versus fCPAP was inconclusive (mean ΔPaCO₂ difference = -1.7 mmHg (95% CI -5.0 to 1.6 mmHg)). Adherence and sleep quality improvements favoured fCPAP, while other outcomes were comparable.

Conclusion: The pilot study highlighted important challenges with recruitment and retention. While the study is not powered to confirm the non-inferiority of APAP, some outcomes appeared to favour fCPAP and APAP use in OHS + sOSA should be approached cautiously. A larger study with protocol modifications is required to confirm these preliminary findings.

Trial registration: ACTRN12618000379213. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374259. Assessing the Efficacy of Auto-titrating versus Fixed Continuous Positive Airway Pressure in Obesity Hypoventilation Syndrome.