METABOLIC CONTROL AND PROGRESSION OF RETINOPATHY - THE DIABETES IN EARLY-PREGNANCY STUDY

OBJECTIVE- To evaluate the role of metabolic control in the progressio n of diabetic retinopathy during pregnancy. RESEARCH DESIGN AND METHOD S- We conducted a prospective cohort study of 155 diabetic women in th e Diabetes in Early Pregnancy Study followed from the periconceptional period to 1 month postpartum. Fundus photographs were obtained shortl y after conception (95% within 5 weeks of conception) and within 1 mon th postpartum. Glycosylated hemoglobin was measured weekly during the Ist trimester and monthly thereafter. RESULTS- In the 140 patients who did not have proliferative retinopathy at baseline, progression of re tinopathy was seen in 10.3, 21.1, 18.8, and 54.8% of patients with no retinopathy, microaneurysms only, mild nonproliferative retinopathy, a nd moderate-to-severe nonproliferative retinopathy at baseline, respec tively. Proliferative retinopathy developed in 6.3% with mild and 29% with moderate-to-severe baseline retinopathy. Elevated glycosylated he moglobin at baseline and the magnitude of improvement of glucose contr ol through week 14 were associated with a higher risk of progression o f retinopathy (adjusted odds ratio for progression in those with glyco hemoglobin greater than or equal to 6 SD above the control mean Versus those within 2 SD was 2.7; 95% confidence interval was 1.1-7.2; P = 0 .039). CONCLUSIONS- The risk for progression of diabetic retinopathy w as increased by initial glycosylated hemoglobin elevations as low as 6 SD above the control mean. This increased risk may be due to suboptim al control itself or to the rapid improvement in metabolic control tha t occurred in early pregnancy, Excellent metabolic control before conc eption may be required to avoid this increase in risk, Those with mode rate-to-severe retinopathy at conception need more careful ophthalmic monitoring, particularly if their diabetes was suboptimally controlled at conception.