The quality of diabetes care among cancer survivors: a retrospective cohort study

Background As cancer survivorship continues to improve, management of co-morbid diabetes has become an increasingly important determinant of health outcomes for people with cancer. This study aimed to compare indicators of diabetes quality of care between people with diabetes and without a history of cancer. Methods We used the Electronic Medical Record Administrative data Linked Database (EMRALD), a database of Ontario primary care EMR charts linked to administrative data, to identify people with diabetes and at least 1 year follow-up. Persons with a history of cancer were matched 1:2 on age, sex and diabetes duration to those without cancer. We compared recommended diabetes quality of care indicators between persons with and without cancer using a matched cohort analysis. Results Among 229,627 people with diabetes, we identified 2275 people with cancer and 4550 matched controls; 86.5% had diabetes diagnosed after cancer. Compared to controls, cancer people with diabetes were significantly less likely to receive ACE inhibitors or angiotensin receptor blockers (OR 0.75 [95% CI 0.64-0.89]), receive statin therapy if age 50-80 years (OR 0.79 [95% CI 0.68-0.92]) and achieve an LDL cholesterol level <2.0 mmol/L (OR 0.82 [95% CI 0.74-0.91]). There were no differences in recommended clinical testing or achieving A1C and blood pressure targets between groups. Conclusion Cancer survivors with diabetes are less likely to receive recommended cardiovascular risk-reducing therapies compared to people with diabetes without cancer of similar age, sex and diabetes duration. Further studies are warranted to determine if these associations are linked to worse survival, cardiovascular outcomes and quality of life.