Psychosocial interventions in breast cancer

Abstract

A broad literature supports the importance of lifestyle, stress, and other psychosocial variables as independent risk factors for cancer and other diseases, whereas positive psychological well being is associated with reduced mortality. The evidence is sufficiently strong to motivate clinical research to evaluate the potential that intervening on these factors would alter the trajectory of these diseases. In their provocatively titled article, Stefanek and colleagues criticize the design and interpretation of results from a recently published clinical trial of psychological interventions for breast cancer patients. Although they raise valid criticisms related to its design and analysis, their recommendation that clinical trials of this nature be suspended until putative mechanisms of action are understood better is inconsistent with the general history of clinical trials in medicine. Moreover, the trial conducted by Andersen et al stands as a considerable accomplishment that deserves a closer look in a broader context. Two major trends have influenced the design and conduct of clinical trials of behavioral interventions. One is a widely held belief that behavioral interventions must be theory-based, reflecting psychological mechanisms of behavior change on 1 hand and addressing biologic mechanisms of disease causality on the other. The effect of these 2 principles on the design of clinical trials has been to include the collection of extensive secondary outcomes that might identify potential moderators and mediators of the intervention as well as biobehavioral mechanisms that might be affected if the intervention shows promise. The trial by Andersen et al is an excellent case in point. The intervention was designed carefully to address all of the biobehavioral pathways that are believed to influence the course of illness and to monitor progress on each. The investigators collected extensive data on stress and depression, health habits, adherence to medical care and indicators of immune function, devising composite indices that included many of these variables. The various measures and methods were detailed in a series of articles that reflect the enormous amount of careful effort expended to design and