COPD & Depression: Severity Matters

The risk of depression in chronic obstructive pulmonary disease patients increases along with disease severity, according to the results of a new study.

Experts in chronic obstructive pulmonary disease (COPD) have reported that a significant portion of patients suffer with depression in addition to battling this treatment-resistant pulmonary affliction. Clinicians should take note because COPD is widespread; it’s the third most common cause of death in the United States, and is expected to gain a similar rank worldwide by 2020.

Many studies have been conducted to estimate depression’s prevalence among COPD patients. A new multicenter study published online on January 7, 2014, in Lung, addresses the association between depression and COPD severity among Korean patients. This study’s strengths include its large number of participants—245 patients with stable COPD—and its use of 3 validated scales:

• The global initiative for chronic obstructive lung disease (GOLD) stage
• The BODE index where B is body mass index, O measures obstruction of airways as measured by FEV₁, D is dyspnea, and E is exercise capacity as measured by a 6-minute walk test
• The Center for Epidemiologic Studies-Depression scale (CES-D), a general self-report measure of depressive symptoms used extensively in epidemiologic studies.

The researchers included the multidimensional BODE index in this prospective study because recent work has shown that it may be superior to the FEV₁-based GOLD stage at predicting risk of diminished quality of life, hospitalization, and death in patients with COPD.

The researchers found that 17.6% of patients with COPD were depressed, and by some measures the prevalence of depression increased as disease severity increased. This finding was apparent when they applied the BODE index, but not when they applied the GOLD staging system. Depression was also 3.67 times more likely in patients who had just an elementary school education than in those who had at least a high school education. Increased dyspnea and poor exercise capacity were also significantly correlated with depression.

This study’s limitations include a small portion of female participants (8%) and limited information on comorbidities and exacerbations that would help characterize patients better. The researchers conclude that clinicians need to screen COPD patients who are at high risk of depression, recognizing that low levels of education and increasing disease severity are risk factors. Practical interventions—counseling, non-pharmacologic interventions and medication—are warranted for these patients.

Ms. Wick is a visiting professor at the University of Connecticut School of Pharmacy and a freelance writer from Virginia.