FEV1 May Not Be Significant Predictor of COPD Exacerbations

Forced expiratory volume over 1 second (FEV₁) might not be a significant factor in the future exacerbation risk for patients with chronic obstructive pulmonary disease (COPD), according to a new report.

Investigators from South Korea conducted a meta-analysis to evaluate the risk of moderate to severe exacerbations in COPD patients. Using a total of 611 patients from 3 prospective COPD cohorts, the investigators examined different models which included GOLD grade (FEV₁), GOLD 2011, and GOLD 2017.

The team noted that the link between GOLD categorizations and future exacerbations had not been fully understood or examined, therefore they wanted to determine if the GOLD 2017 classification would be associated with different future exacerbation risks in COPD patients compared to previous GOLD categorizations. They also set out to determine the impact of the symptoms and FEV₁ on the projected future exacerbation, regardless of a patient’s previous exacerbation history.

GOLD 2017 is a new classification system that updates the GOLD 2011 model. Its most notable updates include removing spirometry measures in categorization of COPD patients, which leaves the categorization onus on symptoms and frequency of exacerbations alone. These changes saw patients in high-risk groups for future exacerbations shift to the low-risk groups.

“The emphasis of the revised document has been to look at patients, ask about symptoms, and ask about exacerbations. That will help you to guide therapy,” Antonio Anzueto, MD, told MD Magazine® in a recent discussion about the proposed changes.

One study that looked into how the changes in these definitions resulted in changes in patient demographics and clinical characteristics. It found that the newly-classified high-risk patients had more clinical characteristics linked to greater risk of acute exacerbations and mortality. There were also some changes in demographics (there were more males, these patients had a lower BMI, and had more chronic bronchitis than the low-risk patients), those study authors reported.

The GOLD 2017 classification did not show any differences in future exacerbation risk compared to GOLD grade or GOLD 2011. However, this was only true for factors excluding FEV₁ categorization criteria. Among patients with no frequent exacerbation history and an FEV₁ ≥50%, investigators determined the group with more symptoms was significantly associated with future exacerbations compared to the group with less symptoms.

They continued that a lower FEV₁ such as <50% was not linked to a higher future exacerbation risk than a higher FEV₁ such as FEV1 ≥50%. This remained true regardless of prior exacerbation history and symptom group.

“The GOLD 2017 classification was not different from GOLD grade and GOLD 2011 regarding the association with future exacerbation risk, and there were no significant differences in exacerbation risk according to FEV₁%,” investigators concluded.

They explained that their research suggests that FEV₁ may not contribute significantly to future COPD exacerbation risk, which partly supports the GOLD 2017 assessment model.

The study, “Acute Exacerbation According to GOLD 2017 Categories in Patients with Chronic Obstructive Pulmonary Disease,” was published online.