HHS Public Access Author manuscript Author Manuscript
JAMA Oncol. Author manuscript; available in PMC 2017 September 01. Published in final edited form as: JAMA Oncol. 2016 September 1; 2(9): 1137–1145. doi:10.1001/jamaoncol.2016.0732.
Analysis of body mass index and mortality in patients with colorectal cancer using causal diagrams Candyce H. Kroenke, ScD1, Romain Neugebauer, PhD1, Jeffrey Meyerhardt, MD2, Carla M. Prado, PhD3, Erin Weltzien1, Marilyn L. Kwan, PhD1, Jingjie Xiao3, and Bette J. Caan, DrPH1 1Kaiser
Author Manuscript
2Dana
Permanente Division of Research, 2000 Broadway, Oakland, CA 94612, USA
Farber Cancer Institute, Boston, MA, USA
3Department
of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta, Canada
Abstract Importance—Physicians and investigators have sought to determine the relationship between body mass index (BMI) and colorectal cancer (CRC) outcomes, but methodologic limitations including sampling selection bias, reverse causality, and “collider” bias have prevented the ability to draw definitive conclusions. Objective—We evaluated the impact of BMI at the time of, and following colorectal cancer (CRC) diagnosis, on mortality in a complete population using causal diagrams.
Author Manuscript
Design—Retrospective observational study with prospectively collected data Setting—Kaiser Permanente Northern California Participants—3,408 men and women diagnosed 2006-2011 with stages I-III colorectal cancer who had surgery Exposures—BMI at diagnosis, and 15 months following diagnosis Main Outcomes and Measures—Hazard ratios for all-cause and CRC-specific mortality, relative to normal-weight patients, adjusted for sociodemographics, disease severity, treatment, and pre-diagnosis BMI.
Author Manuscript
Results—At-diagnosis BMI was associated with all-cause mortality in a nonlinear fashion, with underweight (BMI
JAMA Oncol. Author manuscript; available in PMC 2017 September 01. Published in final edited form as: JAMA Oncol. 2016 September 1; 2(9): 1137–1145. doi:10.1001/jamaoncol.2016.0732.
Analysis of body mass index and mortality in patients with colorectal cancer using causal diagrams Candyce H. Kroenke, ScD1, Romain Neugebauer, PhD1, Jeffrey Meyerhardt, MD2, Carla M. Prado, PhD3, Erin Weltzien1, Marilyn L. Kwan, PhD1, Jingjie Xiao3, and Bette J. Caan, DrPH1 1Kaiser
Author Manuscript
2Dana
Permanente Division of Research, 2000 Broadway, Oakland, CA 94612, USA
Farber Cancer Institute, Boston, MA, USA
3Department
of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta, Canada
Abstract Importance—Physicians and investigators have sought to determine the relationship between body mass index (BMI) and colorectal cancer (CRC) outcomes, but methodologic limitations including sampling selection bias, reverse causality, and “collider” bias have prevented the ability to draw definitive conclusions. Objective—We evaluated the impact of BMI at the time of, and following colorectal cancer (CRC) diagnosis, on mortality in a complete population using causal diagrams.
Author Manuscript
Design—Retrospective observational study with prospectively collected data Setting—Kaiser Permanente Northern California Participants—3,408 men and women diagnosed 2006-2011 with stages I-III colorectal cancer who had surgery Exposures—BMI at diagnosis, and 15 months following diagnosis Main Outcomes and Measures—Hazard ratios for all-cause and CRC-specific mortality, relative to normal-weight patients, adjusted for sociodemographics, disease severity, treatment, and pre-diagnosis BMI.
Author Manuscript
Results—At-diagnosis BMI was associated with all-cause mortality in a nonlinear fashion, with underweight (BMI
