Diabetes Worsens Survival Outcomes in Bladder Cancer Patients: Study
Researchers have found in a Finnish population-based cohort study that diabetes and poor glycemic status were associated with a higher risk of overall and bladder cancer–specific mortality. Further, diabetic patients with bladder cancer showed a worse prognosis than non-diabetics, an effect observed consistently in both men and women. The study was published in the PLoS One journal by Lauri V. and colleagues.
The study had a register-based cohort design and took place in Finland among a population of 14,638 patients with bladder cancer, with follow-up taking place from 1995 to 2012. The information was derived from a combination of three national registers, which offered a complete record of patients with bladder cancer, diabetic status, co-morbidities, and death. Hyperglycemia in patients with diabetes can be measured using blood glucose concentrations or glycated hemoglobin concentrations, hence making it possible to objectively quantify control in diabetic patients after being diagnosed with cancer.
Patient Population and Follow-up
A definite diagnosis of bladder cancer had been established in all patients. Both men and women were studied, which allowed for the assessment of survival differences by sex. Patients were observed for a median of 4.3 years since they were diagnosed with bladder cancer.
The main endpoints were bladder cancer-specific death and all-cause death. Hazard ratios (HR) with 95% confidence intervals (CIs) were calculated using multivariate Cox proportional hazard regression models to assess the associations, adjusting for potential confounders. The effect of post-diagnostic glycemic control status and the use of antidiabetic drugs was tested in particular.
Key Findings
During follow-up, 3,582 patients (24.5%) died from bladder cancer. Diabetes and poor glycemic control were consistently associated with worse outcomes:
Diabetic patients with elevated post-diagnostic blood glucose had a 58% higher risk of bladder cancer–specific death (HR 1.58; 95% CI, 1.10–2.28).
The risk of overall mortality was increased by 50% among patients with diabetes (HR 1.50; 95% CI, 1.20–1.89).
Among hyperglycemic patients, those using antidiabetic medications showed a slightly lower risk increase (HR 1.43; 95% CI, 0.68–3.02) compared with non-users (HR 1.80; 95% CI, 1.13–2.85).
The adverse association between diabetes and prognosis was observed in both male and female patients, indicating a consistent effect across genders.
In this large Finnish study, diabetes and hyperglycemia were both independent risk factors for bladder cancer-specific and all-cause mortality. The findings reinforce the importance of assessing and managing patients with bladder cancer for their metabolic status to better incorporate their diabetic management into their treatment plan.
Reference:
Vuoristo, L., Pöyhönen, A., Vuorlaakso, S. M., Kotsar, A., Tammela, T. L. J., & Murtola, T. J. (2025). Hyperglycemia and bladder cancer prognosis in a Finnish population-based cohort. PloS One, 20(12), e0338215. https://doi.org/10.1371/journal.pone.0338215
