New-onset prediabetes/diabetes worsens overall survival in patients with cancer: A real-world retrospective cohort study.

AIMS: Cancer diagnosis may increase the risk of developing prediabetes/diabetes and subsequently worsen survival in cancer patients. However, it is unclear whether this association is influenced by the timing of hyperglycemia onset or the use of antihyperglycemic medications. MATERIALS AND METHODS: This study leveraged a retrospective cohort, constructed using electronic health record data, of solid tumour patients at the Huntsman Cancer Institute, a comprehensive cancer centre in Utah, USA. Adjusted Cox proportional-hazards regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) to evaluate the association between new-onset prediabetes/diabetes and overall survival. RESULTS: Of the 7300 patients included, 23% developed prediabetes/diabetes after cancer diagnosis (mean time-to-onset = 2.6 years). Patients with new-onset prediabetes/diabetes had worse overall survival compared to patients without prediabetes/diabetes [HR (95% CI): 2.97 (2.48-3.55)]. Compared to patients without prediabetes/diabetes, patients who were not prescribed antihyperglycemic medications had poorer survival than those who were prescribed antihyperglycemic medications (n = 665) [HR (95% CI): 2.52 (2.17-2.93) and 1.70 (1.40-2.06), respectively]. Ever use of metformin was associated with better survival [HR (95% CI): 0.32 (0.15-0.66)] compared to individuals with prescriptions of other non-insulin antihyperglycemic medications, while ever use of insulin was associated with worse survival [HR (95% CI): 1.67 (1.16-2.42)], compared to individuals with prescription of non-insulin antihyperglycemic medications. CONCLUSIONS: Improving clinical practice guidelines for appropriate hyperglycemia monitoring and management, especially in the first 3 years after cancer diagnosis, may improve cancer survival. Early intervention with non-insulin antihyperglycemic medications for control of new-onset prediabetes/diabetes may be crucial in preventing the need for insulin prescription and worsening of survival.