To determine the association between body mass index (BMI) and vertical cup to disc ratio (VCDR) in an Iranian population.

This population-based cross-sectional study conducted on 40-80 years old residents of Yazd district of Iran in 2010-2011. VCDR was estimated by 3 experienced glaucoma specialists, using stereoscopic fundus photography images and VCDR > 0.5 was defined as large cup. BMI calculated using the formula: weight in kilograms / height in square meters, and was categorized into 4 groups including BMI < 18.5 (underweight), 18.5-24.9 (normal), 25-29.9 (overweight) and ≥ 30 (obese).

Of 2320 subjects, 2098 (response rate, 90.4%) participated in the study, and VCDR and BMI data of 1629 individuals (mean age 53.9 ± 9.9 years; 45.6% men) were available. The mean VCDR was 0.34 ± 0.16, and 189 (11.6 %) had large cup. The mean BMI was 27.5 ± 4.6 kg/m2; 36.2 % of individuals were overweight and 34.2 % were obese. No statistically significant relationship was seen between BMI and VCDR (p ₌ 0.79). Gender was not associated with large cup (p ₌ 0.23), but we found statistically significant relation between hypertension (OR=1.53, p ₌ 0.031) and large cup, and similarly between older ages and large cup (OR=1.21, p ₌ 0.002).

BMI has no association with cup size, but individuals with higher blood pressure and older age have larger cup.