Ocular disease may predict all-cause mortality
Eye disease also a predictor of disease’s progress
Patients with retinopathy should be treated for heart disease. That’s the take-home message from a University of Wisconsin study that shows a strong correlation between retinopathy and all-cause mortality.
"Presence of ocular conditions associated with diabetes may identify individuals who should be under care for cardiovascular disease," says Ronald Klein, MD, a professor of ophthalmology at the University of Wisconsin Medical School at Madison.
Investigators examined 996 Type 1 diabetics and 1,370 Type 2s for retinopathy, macular edema, visual acuity, and cataracts in a study that began in 1980. In 1996, the Type 1 patients with the most severe retinopathy, macular edema, and cataracts were at the greatest risk of all-cause mortality and from ischemic heart disease.
Implications of eye disease
Those with proliferating retinopathy were 5.53 times more likely to die of all causes, and 11.02 times more likely to die of ischemic heart disease. Type 1s with severe visual impairment were 4.55 times more at risk for all-cause mortality and 4.66 times more likely to die of ischemic heart disease.
Even after controlling for systemic risk factors for mortality, visual impairment remained a significant predictor of all-cause and ischemic heart disease mortality in the Type 1s.
The severity of retinopathy was associated with all-cause, stroke, and ischemic heart disease mortality in Type 2s. For example, Type 2 diabetics with proliferating retinopathy had 2.27 times the mortality from all causes and 2.07 times the mortality from ischemic heart disease and 2.3 times the death rate than the control group.
The figures for Type 2s with severe visual impairment were striking as well — 2.35 for all cause mortality, 1.32 for ischemic heart disease, and 3.0 for stroke.
"Because vascular disease is involved in most deaths in people with diabetes, there should be a public health benefit accrued from identifying such individuals and monitoring them for heart disease," Klein wrote in the study published in the Archives of Ophthalmology in November.
"These results aren’t really surprising given what we think is a connection between microvascular and macrovascular disease in diabetics," says Andrew Vine, MD, a retinal specialist at the Kellogg Eye Center of the University of Michigan at Ann Arbor. Because diabetics are at huge risk for either type of vascular disease, careful evaluation and close monitoring are an essential part of clinical care, says Vine.
"We know diabetes causes heart disease. It’s just large vessels vs. small vessels that cause the eye disease," he adds. "Nevertheless, this is significant news for diabetics and those who treat them. As clinicians, it’s something we need to think about. When you’re seeing a patient with retinopathy, look for heart disease as well."
Clinicians should be particularly vigilant with patients who smoke, says Vine. "Smoking for a diabetic is close to suicidal because of its effects on the vascular system."
[For more information, contact Ronald Klein at (608) 262-4032 and Andrew Vine at (734) 763-0482.]