Genome-wide study of longitudinal brain imaging measures of multiple sclerosis progression across six clinical trials.

While the genetics of MS risk susceptibility are well-described, and recent progress has been made on the genetics of disease severity, the genetics of disease progression remain elusive. We therefore investigated the genetic determinants of MS progression on longitudinal brain MRI: change in brain volume (BV) and change in T2 lesion volume (T2LV), reflecting progressive tissue loss and increasing disease burden, respectively. We performed genome-wide association studies of change in BV (N = 3401) and change in T2LV (N = 3513) across six randomized clinical trials from Biogen and Roche/Genentech: ADVANCE, ASCEND, DECIDE, OPERA I & II, and ORATORIO. Analyses were adjusted for randomized treatment arm, age, sex, and ancestry. Results were pooled in a meta-analysis, and were evaluated for enrichment of MS risk variants. Variant colocalization and cell-specific expression analyses were performed using published cohorts. The strongest peaks were in PTPRD (rs77321193-C/A, p = 3.9 × 10-7) for BV change, and NEDD4L (rs11398377-GC/G, p = 9.3 × 10-8) for T2LV change. Evidence of colocalization was observed for NEDD4L, and both genes showed increased expression in neuronal and/or glial populations. No association between MS risk variants and MRI outcomes was observed. In this unique, precompetitive industry partnership, we report putative regions of interest in the neurodevelopmental gene PTPRD, and the ubiquitin ligase gene NEDD4L. These findings are distinct from known MS risk genetics, indicating an added role for genetic progression analyses and informing drug discovery.

Diabetic Retinopathy Assessment Variability Among Eye Care Providers in an Urban Teleophthalmology Program.

BACKGROUND: Teleophthalmology is an evidence-based method for diabetic eye screening. It is unclear whether the type of eye care provider performing teleophthalmology interpretation produces significant variability. INTRODUCTION: We assessed grading variability between an optometrist, general ophthalmologist, and retinal specialist using images from an urban, diabetic retinopathy teleophthalmology program. METHODS: Three readers evaluated digital retinal images in 100 cases (178 eyes from 90 patients with type 2 diabetes). Fisher's exact test, percent agreement, and the observed proportion of positive (Ppos) or negative agreement (Pneg) were used to assess variability. RESULTS: Among cases deemed gradable by all three readers (n = 65), there was substantial agreement on absence of any retinopathy (88% ± 4.6%, Pneg = 0.91-0.95), presence of moderate nonproliferative or worse retinopathy (87% ± 3.9%, Ppos = 0.67-1.00), and presence of macular edema (99% ± 0.9%, Ppos = 0.67-1.00). There was limited agreement regarding presence of referable nondiabetic eye pathology (61% ± 11%, Ppos = 0.21-0.59) and early, nonroutine referral for a follow-up clinical eye exam (66% ± 8.1%, Ppos = 0.19-0.54). Among all cases (n = 100), there was acceptable agreement regarding which had gradable images (77% ± 5.0%, Ppos = 0.50-0.90). DISCUSSION: Inclusion of multiple types of eye care providers as teleophthalmology readers is unlikely to produce significant variability in the assessment of diabetic retinopathy among high-quality images. Greater variability was found regarding image gradability, nondiabetic eye pathology, and recommended clinical referral times. CONCLUSIONS: Our results suggest that more extensive training and uniform referral standards are needed to improve consensus on image gradability, referable nondiabetic eye pathology, and recommended clinical referral times.