Can OCT Predict Disability Risk in MS?

There is limited information on the predictive value of optical coherence tomography (OCT)-derived measures. A study sought to determine whether an OCT assessment was predictive of disability risk in progressive multiple sclerosis (PMS) and relapsing-remitting MS (RRMS).

Spectral-Domain OCT, including intraretinal layer segmentation, was performed in 101 patients with RRMS and 79 patients with PMS. All patients had at least one Expanded Disability Status Scale (EDSS) measurement during follow-up, which was a median two years (range, 1.0-5.5 years). The researchers evaluated differences in OCT metrics and their relationship with follow-up disability with analysis of covariance and linear regression models, respectively.

Patients with PMS, compared with those with RRMS, had thinner baseline peripapillary retinal nerve fiber layer (P=0.02) and ganglion cell + inner plexiform layer (GCIPL; P=0.003). When using multivariable models, in patients with RRMS, a significant association was observed between the GCIPL and follow-up disability, with a 0.04 increase in EDSS for every 1-μm decrease in baseline GCIPL (95% confidence interval, 0.006-0.08; P=0.02). Also, in the RRMS group, patients with follow-up EDSS >4 had a thinner baseline GCIPL than patients with follow-up EDSS ≤4. Patients in the highest baseline GCIPL tertile had a significantly lower follow-up EDSS score compared with patients in the middle (P=0.01) and lowest tertiles (P=0.01). Analyses of patients with PMS did not reach the same conclusions.

“Among OCT-derived metrics, GCIPL thickness had the strongest association with short-medium term disability in patients with RRMS. The predictive value of OCT metrics in the longer term will have to be further investigated, especially in PMS,” the study authors concluded.