Ongoing depression is associated with lung function decline and worse respiratory disease outcomes in women, according to a large British study published in the Journal of Affective Disorders.
Depressive symptoms are common in patients with chronic respiratory diseases; however, no longitudinal studies have evaluated the role of persistent depressive symptoms on lung function and respiratory disease outcomes among general populations.
Researchers in England examined the longitudinal relationships of persistent depressive symptoms with subsequent lung function decline and respiratory disease mortality among 4860 general middle-aged and older participants in the English Longitudinal Study of Ageing. Measurements of depressive symptoms were done in study participants during 2 time periods — 2002 to 2003 and 2004 to 2005 — and at least 2 measurements of lung function were done between 2004 and 2013.
The researchers found that during 8 years of follow-up, women with persistent depressive symptoms suffered accelerated lung function decline. In addition, an elevated risk of respiratory disease mortality was observed in women with persistent depressive symptoms compared with women without depressive symptoms. There also appeared to be a dose-response association between cumulative depressive symptom scores and lung function decline in women but not in men.
This study also had several limitations. For example, depressive symptoms were defined by a self-reported questionnaire rather than the diagnosis of depression, which may underestimate the actual occurrence of depressive symptoms. Another limitation of the study is that it was based on an observational cohort, therefore, the possibility of a causal relationship may exist.