In this section
@article{Knox-Brown:2026,
author = {Knox-Brown, B and Sylvester, K and Amaral, A},
journal = {ERJ Open Research},
title = {Physiological quotients for discriminating mortality and respiratory outcomes: a UK biobank cohort study},
year = {2026}
}
TY - JOUR
AB - BackgroundSpirometry is traditionally interpreted using reference-based metrics derived from equations such as those from the Global Lung Function Initiative (GLI). Physiological quotients, which express lung function relative to a lower physiological boundary, have been proposed as an alternative approach. We aimed to compare the prognostic performance of physiological quotients with conventional reference-based metrics including both the GLI 2012 ethnicity-specific and the GLI 2023 Global equations, in a large population-based cohort.MethodsWe analysed data from 270,599 UK Biobank participants aged 40–69 years with baseline spirometry. Physiological quotients were calculated for FEV, FVC, and FEV/FVC using previously established first percentile boundaries. Associations with all-cause and cause-specific mortality, respiratory hospitalisation, respiratory symptoms, and self-reported respiratory diagnoses were examined using Cox proportional hazards and logistic regression models.ResultsOver a median follow-up of 15.7 years, 26,197 (10%) participants died. Lower physiological quotients were consistently associated with adverse outcomes. Each 1-SD decrement in FEVQ, FVCQ, and FEV/FVCQ was associated with higher all-cause mortality (HRs 1.06–1.09), cardiovascular mortality (HRs 1.06–1.20), respiratory mortality (HRs 1.28–1.77), and respiratory hospitalisation (HRs 1.04–1.41). Discrimination for all-cause mortality was modest (C-statistics 0.64–0.65), moderate for cardiovascular mortality (0.72–0.73), and good for respiratory mortality (0.76–0.79). Discrimination of respiratory hospitalisation was modest but slightly higher for FEVQ and FVCQ (0.65) than for percent predicted values and z-scores (0.61–0.62). Across mortality outcomes, discriminative performance was similar between physiological quotients, percent predicted values, and z-scores. ConclusionPhysiological quotients demonstrated prognostic performanc
AU - Knox-Brown,B
AU - Sylvester,K
AU - Amaral,A
PY - 2026///
SN - 2312-0541
TI - Physiological quotients for discriminating mortality and respiratory outcomes: a UK biobank cohort study
T2 - ERJ Open Research
ER -