Correlates of dyspnoea and its association with adverse outcomes in a cohort of adults aged 80 and over

Abstract

Background: adults aged 80 and over, a fast growing age-group, with increased co-morbidity and frailty have not been the focus of previous research on dyspnoea. We investigate the correlates of dyspnoea and its association with adverse outcomes in a cohort of adults aged 80 and over. Methods: about 565 community-dwelling adults aged 80 and over of the BELFRAIL prospective cohort had assessment of Medical Research Council dyspnoea scale (MRC), forced expiratory volume in 1 s (FEV1), N-terminal pro-brain natriuretic peptide (NT-proBNP), physical performance tests, grip strength, 15 items geriatric depression scale, activities of daily living (ADL), body mass index (BMI) and demographics data. Kaplan-Meier survival curves, Cox and logistic multivariable regression, classification and regression tree (CART) analysis assessed association of dyspnoea (MRC 3-5) with time-to-cardiovascular and allcause death (5 years), time to first hospitalisation (3 years), new/worsened ADL disability (2 years), and its correlates. Results: participants with dyspnoea MRC 3-5 (29.9%) had increased hazard ratios for cardiovascular mortality 2.85 (95% confidence interval 1.93-4.20), all-cause mortality 2.04 (1.58-2.64), first hospitalisation 1.72 (1.35-2.19); and increased odds ratio for new/worsened disability 2.49 (1.54-4.04), independent of age, sex and smoking status. Only FEV1, physical performance, BMI and NT-proBNP (in order of importance) were selected in the tree-based classification model for dyspnoea. Conclusions: in a cohort of adults aged 80 and over, dyspnoea was common and an independent predictor of adverse outcomes, with cardio-respiratory and physical performance impairments as key independent correlates. Its routine and comprehensive evaluation in primary care could be very valuable in caring for this age-group.