Abstract
BACKGROUND: To assess ocular surface symptoms, corneal sensitivity (CS), and corneal confocal microscopy (CCM) findings in fibromyalgia (FMS) patients compared to healthy controls and to investigate the effect of oral serotonin-noradrenaline reuptake inhibitor (SNRI) treatment on these parameters. METHODS: Newly diagnosed FMS patients (42 eyes) and healthy controls (50 eyes) were included in this prospective controlled study. 5-Item Dry Eye Questionnaire (DEQ-5), esthesiometry, and CCM were performed. Subbasal nerve plexus was analysed with ACCMetrics, and corneal nerve fibre density (CNFD), branch density (CNBD), fibre length (CNFL), and fractal dimension (CNFrD) were obtained. Dendritic cell (DC) density was measured with ImageJ. Microneuromas were manually counted. Tortuosity was graded using Oliveira-Soto scale. FMS patients received SNRI treatment for 6th months. All measurements were repeated at 3rd and 6th months of treatment. RESULTS: DEQ-5 score was higher in FMS at all follow-ups (p < 0.0001), and decreased with treatment (p < 0.0001). CS in FMS was lower (p = 0.002), with no change following treatment (p = 0.202). CNFL, CNFD, CNBD, and CNFrD values were lower in FMS (p<0.05), and reached the control level at the 3rd month (p>0.05). Tortuosity, microneuromas, and mature DC (mDC) in FMS were higher than control at baseline (p < 0.05). Following treatment, tortuosity in FMS remained higher than in the control (p < 0.05), while mDC and microneuromas showed no significant difference between the groups (p > 0.05). CONCLUSIONS: Ocular symptoms and corneal nerve pathologies were more common in FMS patients compared to healthy controls. Treatment of FMS with SNRIs provided promising outcomes by ameliorating symptoms and improving corneal nerve morphology.