Frequent Exacerbator: The Phenotype at Risk of Depressive Symptoms in Geriatric COPD Patients.

Introduction: Depression is associated with a poorer quality of life and higher rate of COPD exacerbations and mortality. However, with multiple confounding factors, 'independent' risk factor for depression among COPD patients remains ambiguous. Our study aims to identify independent risk factors for depression by specifically evaluating for any independent relationship between frequent exacerbations and various domains of the BODE index on depression.

Methods: This study is a cross-sectional study, conducted in Hong Kong SAR. Age and comorbidity-matched COPD and control subjects were recruited. Depressive symptoms were measured by a validated Chinese version of the Geriatric Depression Scale (GDS-15 items). Prevalence rates of depressive symptoms were compared between COPD and control groups. Predictors for depression (GDS ≥ 8) were determined using univariate and multivariate analyses.

Results: A total of 161 patients (89 and 72 patients, mean ages 75.2 and 75.6 in COPD and control group, respectively) were recruited. Higher prevalence rate of significant depressive symptoms was seen in COPD patients (20.2 vs. 4.2 %, p = 0.006*). Univariate analysis suggested that predictors for depression in COPD patients included (i) exacerbation frequencies in prior year, (ii) dyspnea level, (iii) BMI, (iv) functional status (Barthel index, 6MWD, activity domain of SGRQ), and (v) BODE index. In multivariate analysis, only the 'exacerbation frequencies in prior year' (OR 1.46, p = 0.042*) and 'dyspnea level' (MMRC) (OR 2.75, p = 0.001*) remained significant independent predictors for depression in COPD patients.

Conclusions: A high prevalence of depressive symptoms was observed in COPD patients. 'Frequent exacerbation phenotype' remained a significant independent predictor for depressive symptoms in COPD. Among the BODE index domains, dyspnea level is the most important predictor for depression in COPD patients.