Abstract 81: Dietary supplement use among German colorectal cancer patients: The ColoCare Study.
Authors: Schrotz-King Petra , Dölp Kira , Paskow Michael , Buck Katharina , Abbenhardt Clare , Staffa Jürgen , Tosic Stephanie , Widmer Verena , Scherer Dominique , Habermann Nina , Vickers Kathy , Wilbur Rachel E. , Hoffmeister Michael , Chang-Claude Jenny , Brenner Hermann , Ulrich Cornelia M. 
Published: August 2013

Introduction: Colorectal cancer (CRC) is the second most common type of cancer in the United States and Europe and a leading cause of cancer death in the Western world. Except for age and inherited syndromes, risk factors are mainly lifestyle-related, including diets high in red meat, lack of physical activity, obesity, or smoking. These factors may also affect clinical outcomes among colorectal cancer patients. One potentially relevant health behavior is use of nutritional supplements. The effects of supplement use after diagnosis, and particularly during chemotherapy are unknown, while their use, particularly in the United States, is high.

Objective: To analyze preliminary trends of supplement use over time in CRC patients enrolled at the German study site (Heidelberg) of the international ColoCare Consortium.

Methods: The intake of dietary supplements was assessed among 83 patients recruited from 2010-2012 in the ongoing prospective patient cohort study ColoCare. Data on supplement use, including frequency, duration, dose per day, and type, was obtained by questionnaire. At diagnosis we assessed information regarding supplement use two years prior to diagnosis (TP1) and one month prior to diagnosis (TP2); six months later, we assessed use between TP2 and the six month timepoint (TP3) and at six months (TP4). Demographic and clinical data were obtained by questionnaires and clinical chart abstraction. The distributions of supplement users and non-users with respect to demographic, clinical, and lifestyle factors were assessed using frequency tables and Fisher's exact tests.

Results: In total 33 different supplements were reported, most commonly vitamin use. A tendency towards increased supplement intake after diagnosis was observed. The intake was highest after diagnosis (TP3: 36.1%) compared to prior to diagnosis (TP1: 26.5%) and at six months (TP4:27.7%). Investigation of potential predictors of supplement use, including demographic (sex, age), clinical (tumor stage), and lifestyle characteristics (smoking, income, education) did not show any difference; when supplement use status was categorized by BMI a significant difference was observed at TP2 (p&lt;0.01).

Conclusion: Among German CRC patients, supplement use was highest shortly after diagnosis, and potentially BMI dependent. This increase in supplement use may be important with respect to cancer therapy and potential drug interactions. Continued surveillance through the ColoCare study will investigate the role of supplements in recurrence of disease, and thus support the development of clinical guidelines for supplement use among cancer patients.

Citation Format: Petra Schrotz-King, Kira Dölp, Michael Paskow, Katharina Buck, Clare Abbenhardt, Jürgen Staffa, Stephanie Tosic, Verena Widmer, Dominique Scherer, Nina Habermann, Kathy Vickers, Rachel E. Wilbur, Michael Hoffmeister, Jenny Chang-Claude, Hermann Brenner, Cornelia M. Ulrich. Dietary supplement use among German colorectal cancer patients: The ColoCare Study. [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr 81.