Patients with COPD, depressive symptoms have worse patient-reported outcomes

In patients with COPD, depressive symptoms, compared with lung function, were more strongly associated with worse patient-reported outcomes at baseline and over time.

“The updated GOLD guidelines emphasize patient-reported outcome as a key component of medical management decisions and assessment of disease control rather than lung function alone,” Jacqueline O’Toole, DO, fellow in the division of pulmonary and critical care medicine at Johns Hopkins University School of Medicine, and colleagues wrote in the Annals of the American Thoracic Society. “This shift in approach reflects the increasing amount of literature demonstrating that lung function alone does not fully predict risk of exacerbations or capture disease impact on functional status and patient-reported outcomes such as quality of life.”

O’Toole and colleagues used data from 1,830 individuals with COPD (mean age, 65.1 years; 43% women) from the Subpopulations and Intermediate Outcome Measures in COPD Study to assess COPD morbidity by evaluating differences in baseline 6-minute walk distance and patient-reported outcomes along with their changes over time influenced by depressive symptoms or lung function. They measured depressive symptoms using the Hospital Anxiety and Depression Scale and used FEV₁ percent predicted to measure lung function.

Investigators obtained patient-reported outcomes through SGRQ completion, COPD Assessment Test, Functional Assessment of Chronic Illness Therapy Fatigue and the Modified Medical Research Council Dyspnea Scale.

In the cohort, mean FEV₁ percent predicted was 60.9%. Twenty percent of individuals had clinically significant depressive symptoms, with a baseline mean Hospital Anxiety and Depression Scale of 4.9.

Higher Hospital Anxiety and Depression Scale scores and lower FEV₁ percent predicted were associated with worse patient-reported outcomes at baseline in adjusted models (P < .001).

Compared with FEV₁ percent predicted, depressive symptoms accounted for more baseline variance in SGRQ, COPD Assessment Test and Functional Assessment of Chronic Illness Therapy Fatigue scores, which explained 30% to 67% of heterogeneity, according to the researchers. FEV₁ percent predicted accounted for more baseline variance in the Modified Medical Research Council Dyspnea Scale and 6-minute walk distance compared with depressive symptoms, which explained 16% to 32% of heterogeneity, according to the researchers.

Depressive symptoms accounted for 3% to 17% variance in change over time for patient-reported outcomes, FEV₁ percent predicted accounted for 1% to 4% variance.

“Further analysis of how depression as a major comorbidity of COPD impacts patient-reported outcomes, specifically [COPD Assessment Test], SGRQ and [Modified Medical Research Council Dyspnea Scale], will help the development of more comprehensive approaches to care,” the researchers wrote.