1646-P: The Impact of a Diabetes Codiagnosis on Hospitalisation and Mortality in Patients with Malignancy

Objective: To document the characteristics and outcomes for patients with malignancies with or without diabetes at a tertiary referral hospital. Research Design and Methods: Emergency department and hospital discharge data between 1 Jan 2015 and 31 Dec 2017 were used to identify patients with a diagnosis of a malignancy and diabetes. Multivariate Cox-regression models were used to estimate the effect of diabetes on all-cause mortality. A truncated negative binomial regression model was used to assess the impact of diabetes on length of hospital inpatient stay. Prentice, Williams and Peterson Total Time (PWP-TT) models were used to assess the effect of diabetes on number of Emergency Department presentations and inpatient admissions. Results are presented as incidence-rate ratios (IRR) or hazard ratios (HR). These models were adjusted for age, gender, type of malignancy and Charlson comorbidities. Results: For 7,058 patients identified with malignancies, 1,230(17.4%) were also diagnosed with diabetes. During the three-year study period a diagnosis of diabetes was associated with an increased number of inpatient admissions (adjusted Hazard Ratio (adjHR): 1.14, 95% CI: 1.04, 1.25), increased number of emergency department presentations (adjHR: 1.19, 95% CI: 1.11, 1.28) and length of stay for patients with diabetes (adjIRR: 1.16, 95% C.I: 1.06, 1.28). A co-diagnosis of diabetes was also associated with a 48% increased risk of all-cause mortality (adjHR 1.48, 95% CI: 1.23-1.77). Conclusions: Patients with diabetes had significantly higher numbers of emergency department presentations, inpatient admissions, length of hospital stay and higher rates of all-cause mortality compared to cancer patients without diabetes. This adverse link between diabetes and health outcomes in patients with malignancies requires further exploration.