Official ERS technical standards: Global Lung Function Initiative reference values for the carbon monoxide transfer factor for Caucasians

Abstract

There are numerous reference equations available for the single-breath transfer factor of the lung for carbon monoxide (); however, it is not always clear which reference set should be used in clinical practice. The aim of the study was to develop the Global Lung Function Initiative (GLI) all-age reference values for Data from 19 centres in 14 countries were collected to define reference values. Similar to the GLI spirometry project, reference values were derived using the LMS (lambda, mu, sigma) method and the GAMLSS (generalised additive models for location, scale and shape) programme in R.12 660 measurements from asymptomatic, lifetime nonsmokers were submitted; 85% of the submitted data were from Caucasians. All data were uncorrected for haemoglobin concentration. Following adjustments for elevation above sea level, gas concentration and assumptions used for calculating the anatomic dead space volume, there was a high degree of overlap between the datasets. Reference values for Caucasians aged 5-85 years were derived for, transfer coefficient of the lung for carbon monoxide and alveolar volume.This is the largest collection of normative data, and the first global reference values available for.

Thoracic growth deficiency in childhood cancer survivors may cause overestimation of lung disease

“…In the patients from whom lung volume data were collected and evaluated using the NHANES‐III reference set, percent predicted TLC (87 ± 16% vs 113 ± 25%), RV (83 ± 32% vs 106 ± 45%), and DLCO (80 ± 16% vs 90 ± 25%) were significantly higher when using doubled USL ( P < .001) compared to SH (see Figure A‐D), with Bland Altman biases for percent difference ranging from 18.2 to 22.6% (see Figure S2E‐G). A similar increase in DLCO was observed when using the GLI reference equations (80 ± 14% vs 97 ± 20%, see Figure S3). Percent predicted DLCO/VA was lower with doubled USL (81 ± 11% vs 76 ± 11%, P < .001), with a Bland Altman bias for percent difference of −5.9% (see Figure S2H); height is a parameter used in calculating the predicted DLCO as well as alveolar volume, resulting in comparatively smaller change in this metric versus other measurements.…”

“…For RV, TLC, DLCO, and DLCO/VA, Rosenthal's or Miller's equations were used depending on age . Measurements were also compared to predicted normal values using Global Lung Initative (GLI) reference sets as mentioned in the text. Race‐specific equations were used, when available; otherwise default equations for Caucasians were used.…”

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“…This would bring another definition of normality into the requirements for prescribing. An additional limitation of the reference equations is at extremes of age, our oldest patient was 99 years, beyond the scope of any known reference equation, including those of the GLI …”

“…Since the publication of the ATS/ERS 2017 document, the combined GLI TLco equations have been released for use. Despite being the largest combined data set yet published for TLco, covering an age range of 4.5–91 years, it was unfortunately derived only from a Caucasian population, providing a different but related confounder …”

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“…To date, this has been achieved for spirometry . While equations for the single breath gas transfer test (TLCO) were recently released, data received for non‐Caucasians were insufficient and therefore the GLI TLCO equations are limited to all‐age equations in Caucasians only …”