Patients with diabetes mellitus have a significantly higher risk of developing retinal vein occlusion (RVO) after adjusting for hypertension, hyperlipidemia, congestive heart failure, coronary artery disease, and chronic renal disease, according to a study published in Diabetes Research and Clinical Practice. Additionally, old age, male sex, and hypertension were linked to higher incidence and risk among those with diabetes.
Research has long been associated diabetes with microvascular and macrovascular complications. Sustained high blood glucose levels can cause microvascular abnormalities that involve arteriolar rigidity and the narrowing of retinal vessels in the eyes of patients with diabetes.
To investigate the risk of RVO in new-onset diabetes patients, investigators conducted a nationwide, retrospective, matched cohort study. In the study, 240,761 patients diagnosed with diabetes registered in the Longitudinal Cohort of Diabetes Patients database between January 2003 and December 2005 were age- and sex-matched with a control group of 240,761 patients from the Taiwan Longitudinal Health Insurance Database 2000 who did not have a diabetes diagnosis. Information for each patient was collected from the index date until December 2013. The researchers’ analyses found that the incidence rate of RVO in diabetes patients was 1.91 times higher than that of the control group. Additionally, the relative risk of RVO for patients with diabetes was 1.76 times higher in the full cohort after adjusting for age, sex, and potential confounders.
Specifically, during the follow-up period, 1456 patients with diabetes developed RVO (491 developed central RVO and 965 developed branch RVO). Researchers report a significantly elevated risk of RVO for patients with diabetes compared with the controls (incidence rate ratio=1.91, 95% CI=1.75–2.08). Patients with diabetes showed a significant risk of RVO after adjusting for potential confounders (hypertension, hyperlipidemia, congestive heart failure, coronary artery disease, and chronic renal disease) in the full cohort (adjusted HR=1.76, 95% CI=1.61–1.93). Additionally, patients with hypertension had a significantly higher risk of RVO than patients without hypertension after adjustment for other confounders in the cohort (adjusted HR=1.50, 95% CI=1.36–1.65).
The researchers behind the study note a few limitations, including only having medical histories back to 1996 for study participants. Second, several confounding factors (including blood pressure, alcohol consumption, smoking history, body mass index, serum cholesterol levels, and renal function) couldn’t be ascertained from claims data, which could lead to potential bias. Finally, the diagnoses of diabetes, RVO, and other comorbidities were determined via ICD-9 codes, which may lead to disease misclassification.
Chang Y, Ho C, Chu C, et al. Risk of retinal vein occlusion in patients with diabetes mellitus: a retrospective cohort study. Diabetes Res Clin Pract. Published online December 9, 2020. doi:10.1016/j.diabres.2020.108607