Introduction: The large multicenter studies (EMGT, CNTGS, CIGTS, AGIS) have revealed that lowering the intraocular pressure (IOP) improves the prognosis of primary open angle glaucoma (POAG) but does not stop its progression. In addition to topical drugs, laser and surgical therapy, in recent years, neuroprotection has increasingly been implemented. It is a promising method and its main task is to prevent the death of retinal ganglion cells (RGC) and slow down the progression of the disease.
Aim: The purpose of the study is to observe and compare the effects of using the dietary supplement citicoline as additional therapy for patients with POAG.
Materials and Methods: This study includes the results of the examination of 120 eyes of 60 POAG patients aged 50–75 years, who are undergoing topical anti-glaucoma therapy. Patients were randomly divided into two groups of 30 each (A and B) and followed up for a period of 15 months. The IOP values of the monitored patients were in the 14–21 mmHg range. Group A patients did not take any nutritional supplements that could have positive or negative influence on the study results during the observation period. Group B patients took the food supplement Citizin following a prescribed regimen consisting of two 6-month periods with a 3-month break between them. All patients underwent a complete ophthalmological examination, including standard automated perimetry (SAP) and optical coherence tomography (OCT) before enrolling in the study, after 6 months, and after 15 months. The mean deviation (MD) and pattern standard deviation (PSD) parameters measured by SAP, as well as retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) measured by OCT, were considered.
Results: During the observation period, there was a deterioration of the monitored parameters and progression of the disease in group A. Both MD and PSD deteriorated by 0.22 dB and 0.37 dB, respectively, and mean RNFL and GCC values decreased by 3.37 μm and 2.75 μm, respectively, for Group A over the period of monitoring. An improvement of the parameters in Group B was noted, which was more evident after the second 6-month intake of citicoline. In Group B, MD improved by 0.31 dB and PSD improved by 0.4 dB over the entire observation period. Mean RNFL and GCC values for Group B increased by 1.28 μm and 1.9 μm, respectively, during the same period.
Conclusion: In conclusion, although these results need to be confirmed by further studies with a longer follow-up period and performed on a larger population, and it would be useful to add other tests on optic nerve function and visual pathways, the data from our study show that the dietary supplement citicoline has a positive effect on slowing the progression of POAG at different stages of the disease.
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