A new study suggests even mild dilation of blood vessels in the retina may signal cognitive decline in women 65 or older.
The new multinational study, led by scientists at the University of California, San Francisco (UCSF), links even mild retinopathy to cognitive decline and related vascular changes in the brain.
Researchers believe this discovery implies that simple eye screening could also serve as an indicator of cognitive changes in the brain. They believe that early diagnosis and treatment may potentially reduce the progression of cognitive impairment to dementia.
Another advantage of diligent eye screening is the detection of diabetes or hypertension. Early diagnosis could allow for lifestyle or drug interventions when they might be most effective.
“Lots of people who are pre-diabetic or pre-hypertensive develop retinopathy,” said the lead author of the study, Mary Haan, DrPH, MPH, and UCSF professor of epidemiology and biostatistics. “Early intervention might reduce the progression to full onset diabetes or hypertension.”
Study findings have been reported in the online issue of Neurology and were based on data from the Women’s Health Initiative Memory Study and the Site Examination study.
In the study, the team followed 511 women with an average starting age of 69, for 10 years. Each year, the women took a cognition test focused on short-term memory and thinking processes. In the fourth year, they received an exam to assess eye health. In the eighth year, they received a brain scan.
Of the full group of women, 39 women, or 7.6 percent, were diagnosed with retinopathy. On average, these women scored worse on the cognition test than the other women. They had more difficulty, for instance, recalling a list of several words five minutes after hearing them.
The women with retinopathy also had more damage to the blood vessels of the brain. They had 47 percent more ischemic lesions, or holes, in the vasculature overall and 68 percent more lesions in the parietal lobe.
Researchers believe the holes in the retina are caused by high blood pressure as the lesions are also associated with vascular disease and sometimes stroke.
Another sign of high blood pressure was a thickening of the white matter tracks that transmit signals in the brain.
However, women in the study did not have more brain atrophy — a characteristic of Alzheimer’s disease. This result indicates that retinopathy is a marker of neurovascular disease rather than Alzheimer’s disease, according to Haan.