Comorbid Depression in Patients with Cystic Fibrosis

Comorbid depression must be screened and treated in cystic fibrosis (CF) patients, according to findings presented in BMC Pulmonary Medicine.

Researchers from the University Ulm Medical Centre in Ulm, Germany analyzed 473 German patients (55.4 percent male) with CF in order to determine if elevated symptoms of depression would be a predictor of worsening lung function after 2 years. The patients were aged 12-53 years and were screened for depression using the Hospital Anxiety and Depression Scale (HADS). Lung function (FEV₁% predicted) was assessed at baseline and at 2 years.

Data was collected from the German CF registry about age, gender, professional status, and living situation. A majority of the patients lived with their families or partner (79.3 percent) and were pursuing education or employment (in school 27 percent; in job training 35.5 percent; employed 21.9 percent; unemployed 5.1 percent; retired 10.4 percent).

Lung function at baseline varied across all patients, but the researchers broke the patients into 4 groups: (1) FEV₁% ≤ 40 percent and depressed, 21 patients; (2) FEV₁% ≤ 40 percent and not depressed, 68 patients; (3) FEV₁% > 40 percent and depressed, 17 patients; (4) FEV₁% > 40 percent and not depressed, 367 patients. A small population of patients (38, 8 percent) demonstrated elevated levels of depression while 21 patients (4.4 percent) of them were in the borderline range at baseline.

Nearly 1 in 5 patients (18.8 percent) had severe lung disease at baseline (FEV₁% ≤ 40 percent). However, patients with elevated symptoms of depression varied significantly in their FEV₁%.

The time difference between baseline and the second measurement — 2 years – indicated an average decrease of about 4 percent in the FEV₁. The mean lung function decreased in 3 of the 4 categories; in group 4 (367 patients with FEV₁% > 40 percent and no depression) the number of patients decreased from 74.9 to 70.9 percent in the 2 year study period.

In the group with depression and moderate to good lung function at baseline, researchers noted the greatest decline: an average of 59.6 percent at baseline to 52.0 percent after 2 years. A 3.5 percent decrease was identified in the patient group with poor lung function and symptoms of depression at baseline after 2 years: from 32.2 to 28.7 percent. In an unexpected find, severely ill patients without evidence of depression of baseline increased slightly from 31.2 to 34.3 percent of the FEV₁ predicted.

“A bio-psycho-social model depression should be considered as an important risk factor for disease progression in patients with CF,” the authors wrote. “This backs the position that mental health is a relevant factor as already mentioned in the literature in conjunction with other chronic conditions that impair the respiratory system.”