Out-of-control diabetes may not only put patients at risk of diabetes-related complications but also decrease chances of surviving cancer….
In this observational study, the mortality rates among cancer patients with and without diabetes were studied. A total of 42,205 patients with diabetes prior to cancer diagnosis were identified from an initial 426,129 patients. These patients were then placed into 1 of 4 groups based upon their diabetes status at the time of cancer diagnosis. These groups included: no diabetes, diabetes without medication, diabetes with only oral hypoglycaemic agent (OHA), or diabetes with insulin treatment.
Using Poisson models, the authors found associations between pre-existing diabetes in cancer patients and mortality relative to the non-diabetic cancer population. Overall, cancer patients with diabetes had higher rates of mortality than cancer patients having no diabetes.
Diabetic patients who did not require pharmacological treatment had better survival rates than those requiring insulin. For participants with a duration of diabetes of 2 or more years at time of cancer diagnosis – looking at all cancers – those treated with insulin experienced the highest mortality rate ratios starting from 3.7 (95% CI 2.7, 5.1) for men and 4.4 (3.1, 6.5) for women 1 year after cancer diagnosis. At 9 years post-cancer diagnosis, mortality rate ratios increased to 5 (3.5, 7.0) for men and 6.5 (4.2, 9.3) for women.
In men, researches estimated a 20%, 2-year survival probability in insulin-treated patients and 60% 2-year survival rate for OHA-treated patients and patients without a history of diabetic medication usage. For cancer patients with diabetes this was approximately 70%.
In women, 2-year survival probability was 30% for insulin-treated patients, 70% for OHA-treated patients and without a history of diabetic medication usage and 80% for non-diabetic patients.
There were some limitations to this study. The information about the stage of cancer at time of diagnosis was unknown. Also, this study didn’t control for the different cancer regimens used, socioeconomic factors, medical histories and various other comorbidities that could have influenced the outcomes.
- Patients with more advanced diabetes may have a worse prognosis when it comes to cancer survival
- Properly managing diabetes may not only decrease diabetes-related complications but may also help increase cancer survival chances.
K. Ranc, & M. Jørgensen, S. Friis and B. Carstensen. Mortality after cancer among patients with diabetes mellitus:effect of diabetes duration and treatment. Diabetologia March 2014