To evaluate optical coherence tomography (OCT) thickness of the macula in people with diabetes but minimal or no retinopathy and to compare these findings with published normative data in the literature from subjects reported to have no retinal disease.

Cross-sectional study.

In a multicenter community- and university-based practices setting, 97 subjects with diabetes with no or minimal diabetic retinopathy and no central retinal thickening on clinical examination and a center point thickness of 225 μm or less on OCT (Stratus OCT; Carl Zeiss Meditec, Dublin, California, USA) were recruited. Electronic Early Treatment of Diabetic Retinopathy Study best-corrected visual acuity, seven-field stereoscopic color fundus photographs, and Stratus OCT fast macular scan were noted. Main outcome measures were central subfield (CSF) thickness measured on Stratus OCT.

On average, CSF thickness was 201 ± 22 μm. CSF thickness was significantly greater in retinas from men than retinas from women (mean ± standard deviation, 209 ± 18 μm vs 194 ± 23 μm; P < .001). After adjusting for gender, no additional factors were found to be associated significantly with CSF thickness (P > .10).

CSF thicknesses on Stratus OCT in people with diabetes and minimal or no retinopathy are similar to thicknesses reported from a normative database of people without diabetes. CSF thickness is greater in men than in women, consistent with many, but not all, previous reports. Studies involving comparisons of retinal thickness with expected norms should consider different mean values for women and men.