Medscape Medical News 2007. ©2007 Medscape

Release Date: December 4, 2007

News Author: Pauline Anderson
CME Author: Charles Vega, MD
Disclosures

December 4, 2007 �?A new study has shown that patients with severe chronic obstructive pulmonary disease (COPD) who have moderate to severe depressive symptoms are at an increased risk for 3-year mortality, with those patients scoring 15 or higher on the Beck Depression Inventory (BDI) facing the greatest risk.

Not only did the study conclude that depression is common among patients with COPD, but it also found that, for the most part, these patients are not receiving treatment for their depression. Less than one fourth of patients with depressive symptoms were receiving treatment for these symptoms.

"This study suggests that depression is under-treated among patients with COPD," said Vincent S. Fan, MD, an investigator in the Division of Health Services Research and Development at the Veterans Affairs Puget Sound Health Care System and assistant professor, Division of Pulmonary and Critical Care, University of Washington, Seattle, who was one of the study authors.

"Providers should consider screening for depression since prior research has suggested that treatment can improve respiratory symptoms and anxiety in patient with COPD," he told Medscape Psychiatry.

The new report is published in the November 26 issue of the Archives of Internal Medicine.

Depression Common in COPD

COPD is the fourth leading cause of death in the United States, the study authors write. Patients with COPD are at increased risk for depression, with prevalence among these patients estimated at between 7% and 42%. These patients also have relatively high rates of anxiety, they note, seen in 10% to 16% of this population.

The data for the current study were collected as part of the National Emphysema Treatment Trial (NETT) �?a randomized controlled trial of lung volume reduction surgery vs continued medical treatment �?conducted at 17 clinics across the United States between January 29, 1998, and July 31, 2002. Patients with emphysema and severe limitations of airflow in this analysis were randomized to medical therapy.

Baseline depressive symptoms were measured with the 21-item BDI, and general anxiety was measured with the State-Trait Anxiety Inventory (the State scale asks patients how they feel at a particular point in time, and the Trait scale asks them how they feel in general). Patients then completed 6 to 10 weeks of pulmonary rehabilitation before the randomization.

The analysis for this study included 610 patients. The mean BDI score was 9.3%, with 40.8% of participants scoring 10 or higher (a score usually consistent with mild to moderate depression).

Only 24.5% of patients with mild to moderate depressive symptoms were taking an antidepressant.

During follow-up, 26.9% of study subjects were hospitalized or were seen in the emergency department for COPD, and 30.5% were hospitalized for respiratory tract reasons. The overall 1-year mortality was 7.5%. During the same 1-year period, 25 patients had lung volume reduction surgery (4 later died), and 3 patients had lung transplants.

Significant Increased Mortality Risk

In these study patients, a BDI score of 10 or higher was not associated with hospitalization or mortality after adjustment for severity of disease. However, when the researchers did an analysis using BDI divided into quintiles, they did find a slightly increased risk for 3-year mortality among patients with a score of 11 to 14 vs those with a score of less than 5 (adjusted odds ratio for patients with a BDI score of 11-14 was 1.97) and a statistically significantly increased risk among those with a BDI score of 15 or higher (adjusted odds ratio was 2.74 for patients with a score of 15 or more).

This increased risk remained even after adjusting for severity of disease, something which is necessary in this patient population, said Dr. Fan. "Because patients with more severe COPD have a higher prevalence of depression, adjusting for disease severity is essential to determine the independent effect of depression," he told Medscape Psychiatry.

The study authors noted that it might be necessary to view BDI thresholds differently in patients with COPD. "Symptoms of depression such as psychomotor slowing or fatigue may overlap notably with COPD," they wrote. "Patients in the present study had a mean SD BDI score of
9.3. . .suggesting that for COPD, a higher threshold for depressive symptoms may be needed compared with ischemic heart disease to identify patients at increased risk for adverse outcomes."

The researchers found no association between antidepressant use and mortality. Finally, the study also looked at anxiety and found that baseline anxiety was not associated with the risk for hospitalization or mortality at 1 or 3 years. "Although some studies had suggested that anxiety might increase the risk of COPD hospitalizations, we did not find that anxiety affected the risk of being hospitalized for an exacerbation among patients in the NETT trial," said Dr. Fan.

The study was supported by a grant from the Department of Veteran Affairs Health Service Research and Development Service and by the NETT Coordinating Center. The NETT is supported by grants from the National Heart, Lung, and Blood Institute, by the Centers for Medicare and Medicaid Services, and by the Agency for Healthcare Research and Quality. Six of the study authors have obtained funding.

Arch Intern Med. 2007;167:2345-2353.

Clinical Context

Patients with COPD are at increased risk for mood disorders vs the general population. Up to 42% of patients with COPD have depressive symptoms. However, the authors of the current study note that some symptoms are shared between depression and COPD, such as fatigue, and measurement of depression needs to account for this confounding factor. At the same time, the prevalence of anxiety disorders as a concomitant diagnosis with COPD is between 10% and 16%.

The effect of mood disorders on hospitalizations and mortality among patients with COPD is controversial. The current study addresses this issue.

Study Highlights

• Patient data were drawn from a randomized trial of lung volume reduction surgery for patients with COPD. All subjects had emphysema and severe limitation of airflow with a forced expiratory volume in 1 second of 45% or lower than the predicted value.
• Before lung reduction surgery, all participants were assessed for depression and anxiety with the BDI and State-Trait Anxiety Inventory, respectively.
• The main outcome of the study was the relationship among depression, anxiety, and COPD-related emergency department visits and hospitalizations as well as overall mortality. These outcomes were determined by insurance claims data and were adjusted for COPD severity variables. Participants were followed up for a total of 3 years.
• The current study focused on 610 patients randomized to receive medical therapy. The mean age of the participants was 66 years, and slightly more than one third of subjects were women. The mean BDI score was 9.3, which was near the level associated with mild to moderate depression.
• 40.8% of participants were classified as having at least mild depression, but only 24.5% of these subjects were receiving an antidepressant.
• Rates of COPD-related emergency visits or hospitalizations were 26.9%, and 30.5% of subjects were hospitalized for any respiratory tract reason. The 1-year mortality rate was 7.5%.
• A BDI score of 10 or higher was not independently associated with a risk for emergency department visits, hospitalizations, or 1-year mortality, but it did increase the risk for 3-year mortality (odds ratio, 1.42).
• When BDI scores were divided into quintiles, there were no independent, significant trends between worsening scores and increased rates of hospitalizations or emergency department visits.
• There was no association between antidepressant use and mortality or hospitalizations.
• Women had a higher rate of hospitalization vs men, but depression did not affect this outcome in 1 sex vs the other.
• Anxiety did not promote an independent effect on emergency department visits, hospitalizations, or mortality.

Pearls for Practice

• Previous research has found that the prevalence of depression in patients with COPD is as high as 42%, whereas anxiety may be found in 10% to 16% of these patients. The current study finds that the prevalence of depression in COPD is 40%.
• In the current study, depression was associated with a slight increase in 3-year mortality, but not 1-year mortality, emergency department visits, or hospitalizations because of COPD. Anxiety did not increase rates of hospitalization or mortality.

Original Article HERE

Legal Disclaimer