Patients with type 2 diabetes may experience peripapillary retinal nerve fiber layer (RNFL) loss even if they don’t have diabetic retinopathy (DR), a study in JAMA Ophthalmology reports.

Korean researchers enrolled 63 healthy individuals and 101 patients with type 2 diabetes, including 49 patients without DR (the non-DR group) and 52 subjects with mild-to-moderate nonproliferative DR (NPDR group). The study ran from 2013 to 2015, and participants were followed for thee years. The researchers measured peripapillary and RNFL thickness levels at one-year intervals.

The study reported the baseline mean peripapillary RNFL thickness was 96.2μm in the control group, 93.5μm in the non-DR group and 90.4μm in the NPDR group. During the three-year follow-up, investigators found the values decreased to 95.0μm in the control group, 90.3μm in the non-DR group and 86.6μm in the NPDR group.

Progressive reduction of peripapillary RNFL thickness was observed in healthy controls and patients with type 2 diabetes with or without DR, the researchers noted. However, type 2 diabetes was associated with a greater loss of peripapillary RNFL regardless of whether DR was present.

These findings suggest clinicians should be on the lookout for peripapillary RNFL loss in patients with type 2 diabetes, even in the absence of DR progression, the investigation concluded.