The relationship between retinal neurodegenerative changes and overactive bladder syndrome in multiple sclerosis

This study aimed to compare the neuroaxonal damage of the optic nerve and retina in multiple sclerosis (MS) patients with and without overactive bladder (OAB).

We included patients with MS, divided into two groups, based on the severity of OAB symptoms, as evaluated by the OAB-V8 questionnaire. The groups were compared in terms of each dial of the Expanded Disability Status Scale (EDSS), best-corrected visual acuity, intraocular pressure, peripapillary retinal nerve fiber layer (pRNFL) thickness, macular thickness, and macular ganglion cell-inner plexiform layer (mGCIPL) thickness.

The study involved a total of 120 eyes, 78 eyes from 43 female patients, and 42 from 22 male patients. There were 86 eyes (Group 1) with OAB-V8 score under 8 and there were 34 eyes (Group 2) with OAB-V8 score of 8 or over. EDSS median value was 1 (0-2) for Group 1 and 2 (0.8-3.3) for Group 2 (p = 0.004). A comparison of pRNFL thicknesses showed statistically significant lower average, superior, and inferior median values in Group 2. A comparison of mGCIPL thicknesses showed statistically significant lower values in Group 2 for superior, superonasal, inferotemporal, and superotemporal quadrants CONCLUSION: This study revealed, for MS patients without optic neuritis attacks, there was a higher incidence of OAB when the EDSS score was higher. There was a statistically significant relationship between the existence of OAB and thinning in both mGCIPL and pRNFL. The most relevant factor for OAB was found to be pRFNL inferior quadrant thinning.