Discussion
glaucomatous, VF damage, glaucoma
DISEASE, RECRUITMENT, NEURODEGENERATIVE DISEASES, SECONDARY, GLAUCOMA
This is the first placebo-controlled clinical study evaluating the effect of a medical treatment aiming at improving vision-related QoL in glaucomatous patients. The primary pre-specified outcome of the analysis (difference in the change from baseline at six months) reached statistical significance (Citicoline oral solution did not show any significant effect on the general quality of life (SF-36) which also showed poor correlations with metrics of visual function. The fact that only the visual questionnaire (VFQ-25) and not the general health questionnaire (SF-36) showed a significant improvement suggests that the citicoline effect was more related to visual function than just to the general health status in our study involving glaucoma patients.There is a copious literature supporting citicoline effect in glaucoma and more in general in neurodegenerative diseases [The findings of our trial confirm the effect of citicoline as a neuroenhancer as the short duration of the study did not allow to show any significant disease change. Data on visual field confirm that no progression occurred in the 9-month follow-up time. The “good IOP control” (i.e., 13 mmHg on average in both groups) reinforces the likelihood of a lack of progression in these patients. In fact, differently from what could be observed in another trial, this sample was not selected based on glaucoma progression despite IOP control [Among study limitations, it is worth mentioning the reduced sample size of the study. Of the 220 patients that were planned, only 155 were finally enrolled. The drop-out rate was low (5%), less than predicted, despite the trial period fell completely into “pandemic time.” Average values of composite score in the 2 arms showed that overall quality of life was rather good, similar to the one observed in other clinical trials including patients with moderate glaucoma. It is possible that the reduced statistical power of the study did not allow to find differences in secondary outcomes between citicoline and placebo; and the same comment holds for subscales analyses. Another possible limitation is the lack a of wash-out period between the 2 cross-over phases. We do not think it has had a meaningful impact on our results, as confirmed by the lack of significant differences between the 6-month and 9-month time-points. However, any potential carry-over effect would have acted to dilute the difference between the two arms after the switch, potentially reducing the chances of detecting a significant change from baseline, but this was not the case.To conclude, this trial supports the effect of citicoline oral solution on improving the vision related quality of life, measured by the VFQ-25, with no positive or negative impact on the general quality of life, measured by the SF-36. The VFQ-25 composite score at baseline was generally high, making harder to show an impact of glaucoma on quality of life in the study population. Future investigations should focus on the recruitment of participants with more advanced bilateral VF damage, in whom a compromised quality of life can be more likely observed.