Hemoglobin levels associated with proliferative diabetic retinopathy, but differences noted by sex

Arch Ophthalmol. 2009;127(11):1494-1499.

Higher hemoglobin levels in individuals with type 1 diabetes may confer a higher risk of developing proliferative diabetic retinopathy, although the association varies by sex, according to a study.

In a prospective cohort study of 426 individuals — 213 men and 213 women — with childhood-onset type 1 diabetes, 206 cases of proliferative diabetic retinopathy were identified, with equal distribution between men and women. However, in men, higher hemoglobin levels had a linear and positive association with risk for proliferative diabetic retinopathy, and in women, the association was quadratic. In multivariate analysis, hemoglobin levels remained important in both men and women.

"Other significant multivariable predictors included HbA1c and diastolic blood pressure in both sexes, albumin excretion rate in men, and systolic blood pressure and fibrinogen in women," the study authors said.

High hemoglobin levels also predicted a two-step progression of retinopathy grade and macular edema.