To evaluate the association between body mass index (BMI) and visual field (VF) progression in normal tension glaucoma (NTG) patients.

We reviewed the medical records of 78 eyes of 78 NTG patients who were treated with eye drops for more than 18 months. Age, sex, existence of hypertension (HTN), diabetes mellitus (DM), refractive error, baseline intraocular pressure (IOP), IOP reduction ratio, baseline VF indices including mean deviation (MD) and pattern standard deviation, VF progression rate (MD slope, dB/year), number of eye drops, and BMI were analyzed. The progression of VF was determined by glaucoma change probability analyses (STATPAC 2) using a Humphrey field analyzer.

The mean follow-up in consecutive eyes was 4.4 ± 2.7 years. A total of 18 eyes showed progression and 60 eyes did not. The VF progression rate ( p < 0.001) and number of eye drops ( p = 0.024) showed statistical differences, but age, sex, existence of HTN and DM, refractive error, baseline IOP, IOP reduction ratio, baseline VF index, and BMI did not show a statistical difference between the two groups (all, p > 0.05). However, multiple linear regression analyses showed that a lower BMI was significantly associated with faster VF progression in the progression group (β = 0.078; standard error = 0.030; p = 0.027).

In the group in which VF loss progressed despite treatment with eye drops, a lower BMI was associated with progression of VF loss in NTG patients.