Cigarette smoking, blood pressure and the control of blood glucose in the development of diabetic retinopathy.

We have investigated the relationship between diabetic retinopathy and cigarette smoking, blood pressure, control of blood glucose, duration of diabetes and insulin requirement in a cross sectional study of 193 adult patients attending 2 diabetic follow-up clinics. Multiple discriminate analysis demonstrated that the duration of diabetes was closely related to the development of retinopathy in both sexes. Cigarette smoking was related to retinopathy in men but not in women, although in that group the prevalence of smoking was low. The average blood glucose whilst attending the clinic was weakly related to retinopathy in men only whereas the presence of hypertension was weakly related in women only. Cigarette smoking in men at least may be an aggravating factor for diabetic retinopathy.