Changes in depression symptoms may influence lung cancer survival

New-onset or persistent depression symptoms appeared associated with increased mortality risk for patients with lung cancer, according to results of a prospective, observational study.

However, depression remission conferred a mortality risk comparable to having no depression symptoms, results also showed.

“Depression is the most common psychologic symptom in patients with cancer, and patients with lung cancer are at particularly high risk,” Donald R. Sullivan, MD, MA, assistant professor in the division of pulmonary and critical care medicine at Oregon Health & Science University, and colleagues wrote. “Some patients experience transient symptoms as an initial reaction to their diagnosis, whereas others experience persistent symptoms for years during survivorship.”

To assess how longitudinal changes in depression symptoms affect patient outcomes, Sullivan and colleagues evaluated data gathered from Cancer Care Outcomes Research and Surveillance Consortium from September 2003 through December 2005. They identified 1,790 patients (57% aged older than 65 years; 45% women; 72% white) who were within 3 months of their lung cancer diagnosis.

Patients completed the Center for Epidemiologic Studies Depression scale at diagnosis and 12 months’ follow-up.

Overall, 681 patients (38%) had depression symptoms at baseline. Participants with baseline depression had an increased risk for mortality (HR = 1.17; 95% CI, 1.03-1.32).

Based on longitudinal changes at follow-up, researchers further classified patients as never having depression symptoms (n = 640), having new-onset depression symptoms during treatment (n = 105), having depression remission (n = 156) or having persistent depression symptoms (n = 254).

“Approximately half of the study cohort experienced depression symptoms at some point during the study, and symptoms persisted in most patients,” Sullivan and colleagues wrote.

Patients who experienced remission of depression symptoms at 12-month follow-up (HR = 1.02; 95% CI, 0.79-1.31) had a similar mortality rate as those who were never depressed. However, patients with new onset depression (HR = 1.5; 95% CI, 1.12-2.01) and persistent depression (HR = 1.42; 95% CI, 1.15-1.75) demonstrated greater mortality risks.

“The potential reversibility of the negative effects of depression symptoms deserves further study; if confirmed, this would support the importance of effective mental health treatment,” the researchers wrote.

At baseline, depression symptoms were associated with increased mortality among participants with early-stage disease (HR = 1.61; 95% CI, 1,26-2.04) but not patients with late-stage disease. However, at follow-up, depression symptoms were associated with increased mortality among participants with early-stage disease (HR = 1.71; 95% CI, 1.27-2.31) and those with late-stage disease (HR= 1.32; 95% CI, 1.04-1.69).

Although mental health treatment can lead to depression remission, individual pharmacologic and psychotherapeutic treatments in patients with cancer have yielded mixed outcomes, researchers wrote.

“More recent studies of integrated, collaborative multicomponent depression interventions for cancer care have impressive outcomes,” Sullivan and colleagues wrote. “In a study of patients with lung cancer who had major depressive disorder, a multicomponent intervention including evidence-based psychologic therapies, such as behavioral activation, was associated with significantly improved depression scores and remission rates.”

Researchers acknowledged that these results do not prove causation and patients may have had depression symptoms because they anticipated their mortality. – by Chuck Gormley

Disclosure: Sullivan reports no relevant financial disclosures. One researcher reports a consultant/advisory role with Novartis. Another researcher reports honoraria from UpToDate.