Valproic acid’s effects on visual acuity in retinitis pigmentosa: a systemic review and Meta-analysis

摘要

AIM: To gain a better understanding of the overall efficacy of valproic acid(VPA) treatment for retinitis pigmentosa(RP). METHODS: Publications in PubMed, EMBASE, Cochrane Library, Web of Science and Clinicaltrials.gov were searched for clinical trials of patients with RP assigned to treatment with VPA. Patients’ pre-and post-treatment visual field(VF) and best-corrected visual acuity(BCVA) scores were extracted and compared to assess changes. RESULTS: A total of 78 reports were retrieved and 6 studies involving 116 patients were included in the Meta-analysis.The combined results showed a significant decrease in logarithm of minimal angle of resolution(logMAR) scores,calculated using baseline and post-treatment BCVA(P<0.00001, mean difference=-0.05, 95%CI:-0.05,-0.04,I2=36%) scores, which means there was considerable improvement in visual acuity. Meanwhile, more BCVA changes were observed in short-term(≤6 mo) treatment studies(P<0.00001, mean difference=-0.05, 95%CI:-0.05,-0.04, I2=38%), studies conducted in Asia(P<0.00001,mean difference=-0.05, 95%CI:-0.05,-0.04, I2=4%), studies with a sample size of 30 or fewer patients(P<0.00001,mean difference=-0.05, 95%CI:-0.05,-0.04, I2=38%) and prospective studies(P<0.00001, mean difference=-0.05,95%CI:-0.05,-0.04, I2=0%). However, VPA’s effect on VF was inconsistent across studies(P=0.75, mean difference=-22.76, 95%CI:-160.56, 115.05, I2=68%). CONCLUSION: This Meta-analysis reveals that most RP patients who were treated with VPA showed improvement in BCVA. However, its effect on VF remains inconsistent.VPA may be a promising treatment for RP.