Depression predicts emergency care use in people with chronic obstructive pulmonary disease: a large cohort study in primary care.

Depression is common in people with chronic obstructive pulmonary disease (COPD) and has been associated with a variety of poor outcomes. A large proportion of health care costs in the UK are spent on emergency care. This study examined the prospective relationship between depression and use of emergency care in patients with COPD managed in primary care. This was a twelve-month, prospective longitudinal study of 355 patients with COPD in six primary care practices in the UK. Baseline measures included demographic characteristics, depression and anxiety, severity of COPD, presence or absence of other chronic diseases, and prior use of emergency care. Outcome measures were (a) number of emergency department (ED) visits; or (b) an emergency hospital admission in the follow-up year. Older age, number of comorbid physical health conditions, severity of COPD, prior use of emergency care, and depression were all independently associated with both ED attendance and an emergency hospital admission in the follow-up year. Subthreshold depression (HADS depression score 4-7) was associated with a 2.8 times increased odds of emergency hospital admission, and HADS depression >8 was associated with 4.8 times increased odds. Depression is a predictor of emergency care in COPD, independent of severity of disease or physical comorbidity. Even mild (subthreshold) symptoms of depression more than double the risk of using emergency care, suggesting there is a strong case to develop and deploy integrated preventive strategies in primary care that can promote mental health in people with COPD.