Depression and Anxiety as Moderators for a Behavioral Treatment for Dyspnea in Advanced Lung Cancer.

CONTEXT

Dyspnea (breathlessness) is a distressing and disabling symptom affecting over 70% of patients with advanced lung cancer. Although dyspnea treatments are limited, recent research on a brief, nurse-led behavioral intervention for dyspnea in patients with advanced lung cancer demonstrated improvements in dyspnea-related functioning compared to usual care.

OBJECTIVES

We examined whether depression and anxiety moderate the efficacy of a brief behavioral intervention for dyspnea in advanced lung cancer.

METHODS

This secondary analysis of a randomized controlled trial examined a two-session, nurse-led behavioral intervention for dyspnea in 247 patients with advanced lung cancer. Patients self-reported dyspnea-related functioning (Modified Medical Research Council Dyspnea Scale), multidimensional dyspnea (Cancer Dyspnea Scale), and depression and anxiety (Hospital Anxiety and Depression Scale [HADS]) at baseline and post-treatment (8 weeks later). The PROCESS macro tested depression and anxiety as treatment moderators for dyspnea and probed interactions when P's < 0.15 using the Johnson-Neyman procedure due to reduced power in testing moderators.

RESULTS

Baseline depressive symptoms moderated the intervention's impact on dyspnea functioning (b = -0.074, P = 0.075), with significant benefits observed in those reporting >6 on baseline scores of the HADS-Depression subscale. Any post-treatment improvement on the HADS-Anxiety subscale (b = 0.069, P = 0.135) and improvements of at least 3 on the HADS-Depression subscale (b = 0.671, P = 0.009) significantly enhanced outcomes for total dyspnea and dyspnea functioning, respectively.

CONCLUSIONS

Patients with elevated baseline depression and improved distress may benefit more from this intervention for dyspnea. Considering treatment moderators helps optimize resources, but additional research on treatment adaptations is needed to enhance care for all.