NEW YORK (Reuters Health) – Patients with chronic obstructive pulmonary disease (COPD) – even when their disease is relatively stable – are at increased risk of dying if they are experiencing depressive symptoms, according to research conducted in the Netherlands.

“The association of depressive symptoms and mortality has been demonstrated in COPD patients assessed during or shortly after hospitalization for an exacerbation,” Jacob N. de Voogd, at University Medical Center Groningen and co-investigators report in the March issue of Chest.

In the current study, their goal was to study the association between COPD and depression in 121 consecutive patients referred for pulmonary rehabilitation. The patients, who were a mean of 61.5 years old at baseline, had been clinically stable for at least 6 weeks and did not require an increase in medication or hospitalization. The presence of depressive symptoms was assessed with the Beck depression inventory.

Patients were followed from 1998-2000 until 2007, during which time 76 died. Median survival for those who died was 3.0 years.

In multivariate analysis, the presence of clinically significant depressive symptoms was significantly associated with all-cause mortality, independent of sex, age, and lower exercise capacity (odds ratio 1.93).

De Voogd’s group believes their results “are even more compelling because our patient group was, on average, 10 years younger than the patients in the earlier studies,” making it “more than plausible that age and age-related morbidities are not the only contributing factors.”

They suggest that the mechanism underlying the association may be related to the detrimental effect of depression on the hypothalamic-pituitary-adrenal axis functioning. Also, depression is known to interfere with self-care, as indicated by inadequate diet, continued smoking, lower activity levels, not taking medication as prescribed, and postponing needed health care.

Further research is needed, they conclude, to determine the effects of interventions, such as psychotherapy and antidepressant treatment, on the prognosis of patients with COPD.

Reference:
Chest 2009;135:619-625.