Simple respiratory measurements for the screening of frailty in low-middle income countries

Frailty in older adults is characterised by a reduced capacity to cope with external stressors across multiple physiological systems. The respiratory system is particularly vulnerable to external stressors (respiratory infections, allergies, and smoking) and in turn, an individual’s respiratory capacity may provide a simple means for the identification of frailty. This study assessed the ability of spirometry measurements to screen for frailty in the World Health Organisation (WHO)’s global Study of AGEing (SAGE). The SAGE database provided data on 42,487 people aged over 50 years across six low-middle income countries: China, Ghana, South Africa, India, Russia and Mexico (Wave 1: 2013 – 2015). Frailty was classified using Fried’s frailty criteria. Spirometry measurements included Forced Expiratory Volume in 1 second (FEV1), Forced Vital Capacity (FVC), and FEV1/FVC. The ability of spirometry measurements to accurately identify frailty was determined by several efficacy measurements: area under receiver operator characteristic (ROC) curves (auROC), sensitivity and specificity, positive and negative predictive values (PPV and NPVs), and Youden Index (YI) score. We found that FEV1, FVC and an FEV1/FVC ratio < 80% all showed high discriminatory ability in accurately identifying frailty, independent of chronic respiratory conditions. Results from this study indicate that spirometry measurements can be used to screen for frailty in older adults residing in the community.