Rentinal occlusion foreshadows stroke
MedWire News: Patients with retinal vascular occlusion (RVO) have nearly double the risk for stroke of those without the condition, shows a large study.
In contrast, the risk for myocardial infarction (MI) was unaffected by the presence of RVO.
The study, which appears in the Archives of Ophthalmology, included 4500 patients with RVO and 13,500 without, identified using a health insurance claims database.
During follow-up of about 1.5 years, stroke rates were 1.16 per 100 person-years among RVO patients, compared with 0.52 per 100 person-years among controls.
This equated to a 1.72-fold increase in stroke risk after accounting for the presence of vascular risk factors, including hypertension, cardiac arrhythmias, heart failure, and Charlson Comorbidity Index score (as a measure of general health status).
There was a significant 1.79-fold increase in stroke risk associated with branch RVO and a nonsignificant 1.57-fold increase associated with central RVO. Branch RVO was more common overall, accounting for 63% of the insurance claims.
MI occurred at rates of 0.87 and 0.67 per 100 person-years in patients with and without RVO, respectively. The 1.03-fold risk increase that remained after accounting for confounders was not statistically significant.
The increased stroke risk among RVO patients was consistent across both genders and in younger and older age categories (dichotomized at 65 years). There was a tendency for men and patients younger than 65 years with RVO to also have an increased risk for MI, but this was not statistically significant, and the researchers say that the "clinical significance of these findings is unknown."
Overall, Winifred Werther (Genentech Inc, San Francisco, California, USA) and co-workers say that the increased vascular risk among RVO patients is "not surprising," as RVO patients often have numerous systemic risk factors, such as hypertension, diabetes, and hyperlipidemia.
"These data suggest that physicians and patients should be aware of the possible increased risk of CVA [cerebrovascular accident] but not of MI in patients with RVO," concludes the team.
"Additional studies of large, diverse populations are necessary to confirm these findings."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Eleanor McDermid