Progressive loss of macular ganglion cell–inner plexiform layer (mGCIPL) puts patients with nonproliferative diabetic retinopathy at risk for progression, according to newly published research from Seoul.

Thickness of the mGCIPL can be monitored using optical coherence tomography (OCT). The researchers took a retrospective look at four (or more) years worth of photographs in 87 eyes of Type 2 diabetes patients. In total, 44.8% exhibited two-step diabetic retinopathy progression and 6.9% progressed to the progressive form of the disease. Those who progressed had several traits in common. All exhibited a longer duration of diabetes than patients who did not progress in the timeframe the investigators reviewed. However, they also all had thinner mGCIPL and a greater rate of thinning.

The team suggests that this biomarker can be used to predict and, possibly, prevent long-term changes. Specifically, the study’s abstract notes that two metrics available to eye doctors on OCT scans—baseline mGCIPL thickness and mGCIPL thinning rate—“were significant predictive factors” for progression, along with two neurologic tests (cardiac autonomic neuropathy and conduction velocity of peripheral nerves).