Anderson, Laura N.

Abstract Background: Epidemiological and laboratory-based studies have provided conflicting evidence for a role of ghrelin in colorectal cancer development. We conducted two-sample Mendelian randomization (MR) analyses to evaluate evidence for an association of circulating ghrelin and colorectal cancer risk overall and by sex, cancer subsite, and age at diagnosis. Methods: Genetic instruments proxying plasma total ghrelin levels were obtained from a recent genome-wide association study of 54,219 participants. Summary data for colorectal cancer risk were obtained from a recent meta-analysis of several genetic consortia (up to 73,673 cases and 86,854 controls). A two-sample MR approach and several sensitivity analyses were applied. Results: We found no evidence for an association of genetically predicted plasma total ghrelin levels and colorectal cancer risk (0.95, 95% confidence interval, 0.81–1.12; R2 of ghrelin genetic instruments: 4.6%), with similarly null results observed when stratified by sex, anatomical subsite, and for early-onset colorectal cancer. Conclusions: Our study suggests that plasma ghrelin levels are unlikely to have a causal relationship with overall, early-onset, and sex- and cancer subsite–stratified colorectal cancer risk. Impact: This large-scale analysis adds to the growing body of evidence that plasma total ghrelin levels are not associated with colorectal cancer risk.

Abstract Background Community engagement is commonly used to address social inequities. The Carnegie Foundation offers an optional designation for which U.S. colleges and universities may apply to facilitate better educational outcomes through the institutionalization of community engagement. This study is the first to examine the relationship between Carnegie community engaged status and community health outcomes. Methods Ordinal logistic regression was conducted to investigate the association between the presence of a community engaged institution and county health outcomes, including health behaviors, clinical care relating to access and quality, social and economic factors, and physical environment from the 2016 Robert Wood Johnson County Health Rankings and 2015 New England Resource Center for Higher Education Community engaged list. We examined 820 U.S. counties containing a university or college, 240 of which had a community engaged designation. Results Findings indicated that the presence of a community-engaged institution was positively associated with Clinical Care (OR = 1.99; 95% CI: 1.09, 3.64). Other county health factors were not similarly associated. Conclusions Our findings suggest that community engagement status may be most relevant for achieving better access and quality of clinical care. More research is needed to explore this association in the U.S. and internationally.