Does the 2017 revision improve the ability of GOLD to predict risk of future moderate and severe exacerbation?

ABSTRACT

INTRODUCTION: In 2017 update, GOLD separated spirometry from ABCD classification. OBJECTIVES: The aim was to investigate the predictive reliability of GOLD 2017 grading system in terms of future moderate and severe exacerbations. METHODS: COPD patients were classified into A to D groups according to GOLD 2011 and 2017. Patients who were assigned to C/D groups according to GOLD 2011 were divided into subgroups C 1/D1, C2/D2, C3/D3 according to FEV1 % of predicted and exacerbation history. C1/D1 patients defined as FEV1  < 50% predicted and without ≥2 exacerbations or hospitalization in the last year. RESULTS: A total of 225 patients were enrolled. Among them, 25.8% were in groups C1/D1 according to GOLD 2011. These patients shifted to A/B according to GOLD 2017. C1/D1 patients had a significantly higher risk of future moderate and severe exacerbation compared to A/B (P = 0.018). The risk of future moderate and severe exacerbation was significantly higher in patients with a FEV1  < 50% (P = 0.018).The risk of future moderate and severe exacerbation was higher in GOLD 2017 groups A and B compared to GOLD 2011 groups A and B. CONCLUSION: Low FEV1 was an important risk factor for future exacerbations. Downstaging of C1/D1 patients caused heterogeneity in A/B with including patients with low and high risk of future exacerbation. This resulted in a low discriminative power of GOLD 2017 regarding the risk of future exacerbation in groups A and B. This may cause underestimation of disease severity and inadequate treatment especially in A/B patients with low FEV1 .