Retinal Images Predict Future Stroke Risk

A recent study has demonstrated that retinal photographs can reveal the future stroke risk of hypertensive patients – up to a decade in advance of the event. Reporting in the American Heart Association’s journal Hypertension, a team led by Mohammad Kamran Ikram at the National University of Singapore’s Eye Research Institute, has shown that hypertensive retinopathy is an independent risk factor for stroke in patients with hypertension – even in those whose blood pressure is well controlled with antihypertensive drugs. 

The researchers studied 2,907 patients with hypertension without a history of stroke for a mean follow-up period of 13 years. Patients had retinal photographs taken at the beginning of the study, and the level of hypertensive retinopathy was assessed as either none, mild or moderate/severe. Individuals with a history of either coronary heart disease or diabetes were excluded from the study, as hypertensive and diabetic retinopathies can be difficult to distinguish. 

During the follow-up period, ischaemic stroke occurred in 146 patients and haemorrhagic stroke in fifteen. After adjusting for known stroke risk factors, and compared with patients without retinopathy, stroke risk was 35 and 137 percent higher among patients with mild, or moderate-to-severe hypertensive retinopathy, respectively. Even patients with well-controlled blood pressure had 96 percent increased risk of cerebral infarction – which rose to a 198 percent increase in patients with severe hypertensive retinopathy. 

“These findings suggest that a retinal examination may be valuable for the assessment of stroke risk in patients with hypertension,” the team concludes. It’s also “a non invasive and cheap way of examining the blood vessels of the retina,” Ikram adds although, he cautions, additional studies are needed to validate the utility of the approach for assessing stroke risk in a routine clinical setting.