Blood test to identify retinopathy in Type 1 Diabetics

A routine blood test may identify juvenile-onset diabetic patients at heightened risk for proliferative retinopathy.

In a multivariate analysis of data on 426 people followed over 18 years from Pittsburgh Epidemiology of Diabetes Complications Study, researchers found that each increment of 1 g/dL in hemoglobin was associated with a linear 29% increase in risk for retinopathy in men with type 1 diabetes (95% CI 8% to 54%), and a quadratic 10% risk increase in women (95% CI 0% to 20%).

Notably, only diastolic pressure and glycated hemoglobin were predictive of retinopathy in multivariate analysis for both sexes, while systolic pressure predicted retinopathy in women (HR 1.03 per mm Hg), but not in men.

The researchers noted that the difference in the nature of the relationship between hemoglobin and retinopathy risk between sexes -- linear in men, quadratic in women -- may just be a statistical fluke, arising from the small number of men with hemoglobin levels below 13.5 g/dL.

A U-shaped relationship, indicating increased retinopathy risk for both low and high levels of hemoglobin, is likely to apply to both sexes, they said