Retinal changes predict vascular events in ischemic stroke
MedWire News: Retinal imaging may help assess the risk for recurrent vascular events after ischemic stroke, suggest study findings showing that retinal microvascular changes predict subsequent vascular events, independent of traditional risk factors and stroke subtype.
"These findings are consistent with published data showing associations of arteriovenous nicking (AVN) and focal arteriolar narrowing (FAN) with prevalent and incident stroke in healthy populations," say Deidre De Silva (Singapore General Hospital) and co-authors.
Retinal photographs of 652 acute ischemic stroke patients taken within 1 week of stroke onset were assessed for quantitative and qualitative measures. Follow-up data over 2-4 years were obtained by standardized telephone interview and were then verified with medical records. Regression analysis was then used to identify predictors of recurrent vascular events.
The overall incidence of recurrent cerebrovascular events was 14%, subsequent coronary events was 7%, and incidence of vascular death was 5%. Incidence of any composite vascular event was 20%.
Overall, the prevalence of AVN was 39% (28% mild and 11% severe), of FAN was 57% (51% mild and 6% severe), and of opacification of the arteriolar wall (OAW) was 44% (26% mild and 18% severe).
Patients with severe AVN were 1.92-fold more likely to have recurrent cerebrovascular events than those without AVN. Furthermore, patients with severe FAN were 2.03-, 7.38-, and 2.13-fold more likely to have recurrent cerebrovascular events, vascular death, or composite vascular events, respectively compared with those without FAN. OAW was not associated with any subsequent vascular event.
The cumulative incidence for recurrent cerebrovascular events was 29% among patients with severe AVN, 18% among those with mild AVN, and 15% among those without AVN.
"The association of AVN and recurrent stroke may thus be related to chronic blood pressure elevation, which leads to retinal arteriolosclerosis and is a major risk factor for stroke," say De Silva et al.
Similarly, the cumulative incidence of composite vascular events was 40% for patients with severe FAN, 24% for patients with mild FAN, and 21% for patients without FAN.
Severe AVN and severe FAN were predictors of recurrent cerebrovascular events, with respective hazard ratios (HRs) of 2.28 and 2.75, after adjusting age, gender, hypertension, diabetes, ischemic heart disease, smoking, severe carotid disease, atrial fibrillation, and stroke subtype, Severe FAN also predicted composite vascular events (HR=2.77) and vascular death (HR=10.61).
Further analysis showed that among patients with retinopathy (19%), the HRs for composite vascular events, recurrent cerebrovascular events, subsequent coronary events, and vascular death were 1.58, 1.72, 1.83, and 1.95, respectively.
However, the associations of retinopathy with cerebrovascular events and composite vascular events were no longer significant after adjusting for age, gender, hypertension, diabetes, ischemic heart disease, smoking, severe carotid disease, atrial fibrillation, and stroke subtype.
"Retinal imagining has a potential role in predicting the risk of recurrent vascular events after ischemic stroke and in understanding novel vascular risk factors," conclude the authors in the journal Neurology.
By Ingrid Grasmo