Abstract
In diverse human malignancies, including lung cancer, quality of life (QOL) affects the clinical outcome of patients. Many QOL dimensions, however, are influenced by physical status. The current study was undertaken to delineate the role of depression, a state of mind not necessarily influenced by somatic factors. All patients, seen for a newly diagnosed carcinoma of the lung, received a copy of the Self-rating Depression Scale (SDS) proposed by W.W.K. Zung. One hundred and thirty three patients were able and willing to complete the questionnaire. A depression index was calculated, as originally described. Nineteen other prognostically important variables were recorded and available for evaluation. Among the 95 patients who completed all 20 items included in the questionnaire, 53 had an SDS index < or = 50 (no depression), while 42 were moderately or severely depressed (SDS index >50). The survival of depressed patients was significantly lower (p=0.048). Diverse SDS subscales were associated with survival, in either univariate or multivariate analysis. SDS item 19, "I feel that others would be better off if I were dead", emerged as the most significant one. A multivariate model of survival, constructed using only SDS data, had a global Chi-squared value of 29.78, and a p-value of 0.00023. Based on this evidence, it appears that a relationship does exist between patients' depression and prognosis, at least in lung cancer. Further studies are needed to clarify the prognostic effect of depression in more specific (and homogeneous) subgroups of patients.
