Eyes may hold the key for stroke diagnosis in patients with high blood pressure.
Photographing the retina of high blood pressure patients may help detect stroke risk according to new research published in American Heart Association journal Hypertension.
High blood pressure is the world’s single most important risk factor for stroke, yet, it is impossible to predict which hypertension patients are most likely to develop a stroke. According to this study, photographing the retina (retinal imaging) may help detect which patients are more likely to have a stroke.
The study’s lead author, Mohammad Kamran Ikram, M.D., Ph.D., explained that “the retina provides information on the status of blood vessels in the brain” and retinal imaging is a non-invasive and cheap way to examine the blood vessels of the retina.
Researchers tracked stroke occurrence for an average of 13 years in 2,907 patients with high blood pressure who had not previously experienced a stroke. At baseline, each had photographs taken of the retina, the light-sensitive layer of cells at the back of the eyeball. Damage to the retinal blood vessels attributed to hypertension — called hypertensive retinopathy — evident on the photographs was scored as none, mild or moderate/severe. During the follow-up, 146 participants experienced a stroke caused by a blood clot and 15 by bleeding in the brain.
Researchers adjusted for several stroke risk factors such as age, sex, race, cholesterol levels, blood sugar, body mass index, smoking and blood pressure readings. They found the risk of stroke was 35 percent higher in those with mild hypertensive retinopathy and 137 percent higher in those with moderate or severe hypertensive retinopathy. Even in patients on medication and achieving decent blood pressure control, the risk of a blood clot was 96 percent higher in those with mild hypertensive retinopathy and 198 percent higher in those with moderate or severe hypertensive retinopathy.
Ikram, who is also assistant professor in the Singapore Eye Research Institute, the Department of Ophthalmology and Memory Aging & Cognition Centre, at the National University of Singapore, said that “it is too early to recommend changes in clinical practice. Other studies need to confirm our findings and examine whether retinal imaging can be useful in providing additional information about stroke risk in people with high blood pressure.”