Minimal Clinically Important Differences in COPD Lung Function

Abstract

The FEV1 is widely used by physicians in the diagnosis, staging, treatment, monitoring, and establishing prognosis for patients with COPD. The MCID is the smallest difference which patients perceive as beneficial and which would mandate a change in patient management. A precise MCID for FEV1 has not been established. In attempt to establish a MCID for predose or trough FEV1, several limitations need to be addressed. There are issues such as reproducibility, repeatability, acceptability, variability, placebo effect, and equipment effects. Patient factors, such as baseline level of FEV1, albuterol reversibility, diurnal variation, influence the results. Nonetheless, using anchoring techniques, a change in pre dose FEV1 of about 100 mL can be perceived by patients, correlates with fewer relapses following exacerbations and is in the range usually achieved with bronchodilators approved for COPD. In the future, consistent reporting of spirometric variables, such as a predose FEV1 and other outcomes, can be incorporated into a more quantitative effort to establish the MCID. Also distributional/statistical methods may be useful in determining the MCID FEV1.

Critical Steps: A Non-Interventional, Multicenter, Prospective, Observational Study on Critical Handling Errors with DPI Use, in Asthma and COPD Patients

“…Also, significant correlations have been observed between ΔACQ and FSI-10 (p=0.019), and ΔCAT and FSI-10 scores (p=0.001), suggesting that patients who have an improved perspective of their health status are more satisfied by their inhalers and vice versa. The improved viewpoint on their condition is further confirmed by spirometric data, where statistically significant and clinically important FEV 1 changes have been observed in both COPD and Asthma patients [31][32][33][34]. The latter is in agreement with recent bibliographic data that report positive correlations between satisfaction from inhaler devices with improved adherence and clinical outcomes [1].…”

A Network Meta-Analysis of Long-Acting Muscarinic Antagonist (LAMA) and Long-Acting β2-Agonist (LABA) Combinations in COPD

“…Clinically relevant improvements were observed versus placebo over the 12-and/or 24-week time frame in trough FEV 1 (improvements of C100 mL [39]), SGRQ total score (improvements of C4 units [40]), and TDI focal score (improvements of C1 unit [43]) with all FDC therapies, with the exception of TIO/OLO and ACL/FOR, both of which failed to show clinically relevant improvements in SGRQ total score at 24 weeks. Although no MCID has been established for rescue medication use, improvements were observed with all FDCs versus placebo at 12 and 24 weeks, with probabilities of improved outcomes of C92%.…”

“…All improvements were greater than the minimal clinically important difference (MCID) of 100 mL [39]. In comparison with TIO, all combination therapies were superior, with probabilities of improved outcomes of C94% (ESM Table S6).…”

Effect of tiotropium on quality of life in COPD: a systematic review

“…[33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] Of the 24 publications that met the inclusion criteria for this systematic review (see Table 1), 16 compared tiotropium with placebo, [50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65] seven compared tiotropium with an active comparator, [66][67][68][69][70][71][72] and one compared tiotropium with both placebo and an active comparator. 73 The QoL outcomes reported in the 24 included publications were mostly SGRQ and/or TDI (Tables 2 and 3).…”