Flyer Should Include Your Name, the Date/Time/Location of the Defense, the Members of Your
School of Community Health Sciences
Department of Environmental and Occupational Health
In partial fulfillment of the requirements for the degree of
Doctorate of Public Health
Sanae El Ibrahimi
will defend her Dissertation:
The role of Pre-existing Type 2 Diabetes Mellitus on Colorectal Cancer Stage and Survival in Elderly Americans: a SEER-Medicare Population-Based Study
Abstract
Diabetes affects 26% of elderly Americans; yet its impact on colorectal cancer (CRC) outcomes, particularly stage at diagnosis, risk of death and variations by diabetes severity status (complications vs no complications) among the elderly population have not been adequately studied. The purpose of this study is to investigate these effects with a particular focus on the Hispanic group.
The Surveillance Epidemiology and End Results (SEER)-Medicare linked datasets provided data on Medicare beneficiaries 67 years and older who were diagnosed with CRC between 2002 and 2011. Pre-existing diabetes was ascertained from the Medicare inpatient and outpatient claim files using validated algorithms. Odds of advanced vs localized CRC stage at diagnosis were calculated using logistic regression models. Cox proportional hazards models generated hazard ratios (HR) of mortality risk by diabetes status. Models were adjusted for relevant clinical and demographic factors.
The analyses included 93,710 patients with CRC. Among these patients, 22,155 (24%) had diabetes prior to CRC diagnosis and, of these, 17% had diabetes-related complications (neuropathy, nephropathy, retinopathy or peripheral circulatory disorders). The regression models showed no significant association between pre-existing diabetes and CRC stage at diagnosis (odds ratio (OR) = 0.99; 95% confidence interval (CI) = 0.95-1.02 for diabetes without complications and OR = 0.96; 95% CI = 0.90-1.03 for diabetes with complications). Similar results were observed for Hispanic patients. Overall mortality was significantly higher among diabetic patients compared to non-diabetic patients (HR = 1.20; 95% CI = 1.17-1.23). Diabetes with complications substantially increased risk of total mortality by nearly 50% (HR = 1.47; 95% CI = 1.34-1.54). Patients who had diabetes with complications were 16% more likely to die of colorectal cancer (HR = 1.16; 95% CI = 1.08-1.25) compared to patients without diabetes. Among Hispanic CRC patients, diabetes was an independent predictor of poor survival from all-cause mortality but not of CRC cause-specific of death.
This large epidemiological population-based study provides evidence that pre-existing diabetes contributes to poorer overall survival in patients with colorectal cancer and increased mortality from CRC in diabetes with complications. Because these diseases are more prevalent among the elderly, this group is more likely to have both diseases at the same time and more clinicians will need to develop care plans that are interdisciplinary and take into consideration the added burden of diabetes among CRC patients. Hispanic patients with diabetes and CRC did not show variations in outcomes from the general cohort.
Date: Wednesday November 8rd, 2017
Time: 2:00pm
Location: BHS 505
Faculty, students, and the general public are invited.
Committee in Charge:
Dr. Paulo Pinheiro, Advisory Committee Chair
Dr. Tim Bungum, Advisory Committee Member
Dr. Brian Labus, Advisory Committee Member
Dr. Daniel Young, Graduate College Representative