Blog | Thursday, August 15, 2013

QD: News Every Day--Look into the eyes to predict stroke risk

Retinal photographic assessment of hypertensive retinopathy may be useful for assessing stroke risk, as people with it were more than twice as likely to develop stroke, a study found.

Researchers reviewed data from the Atherosclerosis Risk in Communities (ARIC) Study to consider nearly 3,000 participants with hypertension ages 50 to 73 years, who had gradable retinal photographs; no history of diabetes, stroke or coronary heart disease; and subsequent data on stroke.

Experienced reviewers assessed retinal photographs for hypertensive retinopathy signs and classified them as none, mild, and moderate/severe. Results appeared online at Hypertension on Aug. 14.

The most common sign of hypertensive retinopathy were focal arteriolar narrowing (22.3%; 95% confidence interval [CI], 20.8% to 23.8%), arteriovenous nicking (17.5%; 95% CI, 16.1% to 18.9%]), and other retinopathy signs such as microaneurysms, soft exudates, blot hemorrhages and flamed-shaped hemorrhages (5.1%; 95% CI, 4.3% to 5.9%).

Slightly more than 1,400 people (48.4%; 95% CI, 46.5% to 50.2%]) had no retinal hypertension. More than 1,350 (46.6% 95% CI, 44.8% to 48.4%) had mild cases and 146 (5%) had moderate cases. One person had severe hypertensive retinopathy and was included in the moderate group (5.1%; 95% CI, 4.3% to 5.9%).

After a mean follow-up of 13 years, there were 146 cerebral infarctions and 15 hemorrhagic strokes.

For the entire study population there were 0.436 (95% CI, 0.42 to 0.45) strokes per 100 person-years. Among those with no retinopathy, the rate was 0.322 (95% CI, 0.305 to 0.339) per 100 person-years, among those with mild retinopathy, he rate was 0.493 (95% CI, 0.466 to 0.519) per 100 person-years, and among those with moderate retinopathy, the rate was 1.073 (95% CI, 0.899 to 1.246) per 100 person-years.

Patients with moderate hypertensive retinopathy were more likely to have stroke compared to no retinopathy (hazard ratio [HR], 2.37; 95% CI, 1.39 to 4.02). Among patients with good control of blood pressure through medication, hypertensive retinopathy was associated with an increased risk of cerebral infarction for mild retinopathy (HR, 1.96; 95% CI, 1.09 to 3.55) and moderate retinopathy (HR, 2.98; 95% CI, 1.01 to 8.83).

Researchers noted that because medical control of blood pressure may not be sufficient for stroke prevention in patients with hypertension, retinal assessment may be useful.

An editorial noted the advantages to ophthalmoscopy: “Although ophthalmoscopy is a skill that takes time, practice, and perseverance to master, proficiency pays dividends in the hypertension clinic and the stroke prevention clinic, as this study and others clearly show. The retina is the one place in the body where the physician can actually directly inspect the body’s microvasculature, the tissue most directly at risk from hypertension. ... It is a skill that can be relearned (when lost), particularly when retinal photographs are available for comparison with one’s own ophthalmoscopic examination.”