DO PSYCHOLOGICAL-FACTORS INFLUENCE SURVIV AL IN CANCER-PATIENTS .2. FINDINGS OF AN EMPIRICAL-STUDY WITH LUNG-CANCER PATIENTS

The present prospective test study of hypotheses addressed the questio n whether psychological factors are predictive of survival time in lun g cancer patients. The hypotheses were: Emotional distress, depression and depressive coping are associated with shorter survival; hope and active coping with longer survival. The study was based on a sample of n = 103 patients who were investigated post-diagnosis and before the beginning of primary treatment. Emotional distress and hope were asses sed by clinical scales (self-reports and interviewer ratings), depress ion by the Depression Scale of von Zerssen, depressive coping and acti ve coping by the Freiburg Questionnaire on Coping with Illness by Muth ny. At follow-up, which took place three to five years later, n = 74 p atients had died, for n = 29 patients the survival data are censored. The prediction of the survival time was performed applying multivariat e analyses (Kaplan-Meier-method, Cox-Regression), adjusting for biolog ical risk factors (histological classification, stage of the disease, type and amount of treatment, karnofsky performance status, age). Resu lts were as follows: Active coping and hope were associated with longe r survival, emotional distress, depression and depressive coping with shorter survival, respectively. These associations were found consiste ntly across assessment methods. The predictive effects of coping and d istress were statistically independent of the influence of the somatic risk factors. The best psychological predictor was the interviewer ra ting of active coping. Its predictive power equalled that of the Karno fsky performance status. However, there was evidence that the effects of the psychological factors varied somewhat in interaction with treat ment modalities. The findings are discussed from a methodological pers pective. Possible causal models and mechanisms are presented which cou ld account for interactions of psychological measures and the course o f the disease: Thus, it can be conceived that psychological effects we re mediated by patients' compliance with medical treatment. In additio n, it cannot be ruled out that psychological factors themselves were i nfluenced by the physical status of the patients at the time of entry to the study.