The findings of a new study show that acute exacerbations are related to a significant long-term decline in lung function in patients with COPD. For the study, Mark T. Dransfield, MD, lead researcher, and colleagues recruited participants from the COPDGene study. The patients were the first 2,000 to receive a 5-year follow-up for COPDGene, and also included those with and without COPD who were current and former smokers.
The research team used the Global Initiative for Chronic Obstructive Lung Disease guidelines to determine the severity level of COPD, reports Healio, and patients without COPD but with Preserved Ratio Impaired Spirometry (PRISm) were identified. PRISm patients had reduced FEV1 (< 80% of expected) but a normal FEV1/FVC ratio (> 0.70%).
In participants without COPD, treatment with antibiotics or systemic steroid was required to be considered an exacerbation or acute respiratory event, whereas hospitalization was required to be considered a severe exacerbation. The results of the study showed that 36.7% of participants from all groups experienced exacerbations and/or severe exacerbations within the last 5 years.
According to Healio, FEV1 decline in excess of predicted time-dependent factors, such as aging, was linked to exacerbations in patients with COPD. In addition, the greatest decline in FEV1 occurred in patients with mild COPD. Each exacerbation and severe exacerbation was associated with an additional reduction of 23 mL/year and 87 mL/year, respectively.
Statistically significant declines in FEV1 with each exacerbation also occurred in patients with moderate or severe COPD; however, the declines were smaller than those with mild COPD, reports Healio. In addition, decline in FEV1 did not occur in smokers without COPD who experience an acute respiratory event or in PRISm patients who experienced a 9 mL decline in FEV1, and former smokers only experience a 2 mL decline.
“Very early on in this disease — at a time when outside a study like ours the majority of people would not have been diagnosed with chronic obstructive pulmonary disease (COPD) — patients appear to be losing lung function,” says Dransfield. “The whole medical community is focused on the latter stages of COPD, when, like diabetes and heart disease and other chronic diseases, we should probably be focused on preventing morbidity much earlier.”
According to the researchers, the findings suggest that preventing exacerbations in patients with mild COPD “could reduce the risk of developing severe COPD.”