Nicht-Ausfüllen von Fragebögen zur Lebensqualität als Risikofaktor für geringes Überleben bei Rektumkarzinom-Patienten. Ergebnisse der Fünf-Jahres Feldstudie Marburg-Biedenkopf

Abstract

Background: Recent studies investigated the role of low quality of life (QL) as a prognostic factor for low survival in surgical cancer patients. In a prospective field study including all patients in a given two year recruitment period we were able to show that patients who were objectively less healthy were also less likely to fill in questionnaires and at the same time had a higher risk of having critically low quality of life scores. Based on this observation, the present analysis focuses on the question whether non-compliance with filling in QL-questionnaires (rather than low quality of life scores) is related to lower five-year survival. Methods: Prolective cohort study in a defined region (small area analysis). Inclusion criteria were newly diagnosed rectal carcinoma and treatment in the study region in either one of three hospitals in the period between 01.01.1997 until 31.12.1998. QL was assessed at discharge from clinic and at each follow-up using the EORTC QLQ-C30 plus CR38. Tumor documentation was comprehensive and included classification, diagnosis, type of therapy, progression and time and cause of death. Univariate (Kaplan-Meier) and multivariate (Cox-Regression) survival analyses are being presented. Results: 146 consecutive patients with newly diagnosed rectal carcinoma were recruited; these were all patients of a defined region in a two year period. 141 patients received surgery, 116 in the university clinic, 25 in two peripheral hospitals. Types of surgery were: 89 rectal resection, 33 rectal extirpation, 19 other. 46 patients received adjuvant therapy. At discharge from clinic 61 patients (42%) refused to fill in a QL-questionnaire, 44 (30%) had a low overall QL of <50 score points, 41 (28%) had a higher QL of > 50 score points. Overall median survival in the five year period was 50 months, 67 of 146 (46%) patients died within the five-year observation period. The multivariate Cox regression included seven predictor variables, three of them had a statistical effect on five-year survival: ASA (p = 0.014), UICC (p = 0.039), and filling in the questionnaire (p = 0.049). Non-compliers with QL-assessment had a median survival of 22 months, significantly less than those with either low (55 months) or higher (54 months) overall quality of life, Kaplan-Meier log rank = 21.08, p< 0.001. Discussion: To our knowledge this is the first report in the literature showing that non-compliance with QL-assessment is an independent predictor of five year survival. The mechanisms underlying this effect have to be specified in further studies (e.g., overall low compliance, resignation, low motivation due to bad health or less-than-optimal therapeutic management). In any event, it appears that in our study those patients who would have profited most from QL-diagnostics and QL-related aftercare did not fill in the questionnaires.