A recent review found a likely association between diabetic retinopathy and increased risk of stroke with type 1 and type 2 diabetes.
A review published in Journal of Endocrine Society found that type 1 (T1D) and type 2 diabetes (T2D) may predispose patients to a higher risk of stroke if they have diabetic retinopathy (DR). The researchers found that the association with T2D was stronger than with T1D.
The investigators searched PubMed, Web of Science, Embase, and Cochrane Library for studies from 1976 to 2022 that were published in English. Studies needed to be population-based retrospective studies, cohort studies, or randomized controlled trials to be included in the review.
Nineteen studies were included in this review that totaled 45,495 patients for analysis. Four of the studies included patients with T1D and 16 included patients with T2D.
The comprehensive analysis for patients with T2D included 13 studies, which included 34,208 patients with a mean follow-up of 6.87 years. DR was found to have a significant association with stroke events (odds ratio [OR], 1.78; 95% CI, 1.53-2.08). There were only 4 studies that did not find an association between the 2 conditions.
The 4 studies with 6762 patients with T1D with a mean follow-up of 10.52 years found that the presence of DR was not significantly associated with stroke events (OR, 1.77; 95% CI, 0.48-6.61).
A comprehensive analysis that involved the HR as an effect measure was done for 10 studies with 6762 patients. The pooled HR for any DR was found to have an association with the HR for stroke events (HR, 1.62; 95% CI, 1.28-2.06).
A pooled analysis of DR severity found that nonproliferative diabetic retinopathy (NPDR) had a significant association with the HR for stroke events (HR, 2.01; 95% CI, 1.45-2.78). The HR for severe NPDR was also associated with the HR for stroke events (HR, 2.27; 95% CI, 1.52-3.39).
There were some limitations to this review. It’s possible that the studies used different diagnostic criteria, disease definitions, and statistical methods, which may have led to changes in the review results. Inconsistency of results may have been due to different treatments for the disease, and strokes were mostly counted as an outcome for cardiovascular disease, which may lead to less comprehensive data. Treatment of DR was not often a baseline variable.
The researchers concluded that their review identified an association between DR and stroke, with patients with T2D at more risk than patients with T1D.
“Screening for DR should be considered as a routine procedure in the assessment and management of stroke risk,” the authors wrote.
Wang Z, Cao D, Zhuang X, et al. Diabetic retinopathy may be a predictor of stroke in patients with diabetes mellitus. J Endocr Soc. 2022;6(8):1-9. doi:10.1210/jendso/bvac097