High caloric and sodium intakes as risk factors for progression of retinopathy in type 1 diabetes mellitus.

OBJECTIVE: To report the association of dietary nutrient intakes in relation to the 6-year progression of diabetic retinopathy (DR) in African American patients with type 1 diabetes mellitus.
METHODS: African American patients with type 1 diabetes who participated in the baseline and 6-year follow-up examinations as part of the New Jersey 725 study were included. At the baseline examination, a food frequency questionnaire was used to document average daily dietary nutrient intakes. Clinical evaluations at baseline and at the 6-year follow-up also included a structured clinical interview, ocular examination, grading of 7 standard field stereoscopic fundus photographs, and blood pressure measurements. Biological evaluations included blood and urine assays. Nutrient intake data were analyzed using DietSys software and nutrient databases developed by the National Cancer Institute.
RESULTS: Among the 469 participants at risk for progression of DR, baseline total caloric intake was significantly associated with 6-year incidence of vision-threatening DR (either proliferative DR or macular edema) and of severe hard exudates--after adjusting for clinical risk factors for DR progression. Baseline high sodium intake was a significant and independent risk factor for 6-year incidence of macular edema.
CONCLUSIONS: In African American patients with type 1 diabetes, high caloric and sodium intakes are significant and independent risk factors for progression to severe forms of DR. Dietary recommendations of low caloric and sodium intakes may be beneficial in relation to the development of DR.