Supplementary Material for: Therapeutic effects of umbilical cord serum for dry eye disease: a systemic review and meta-analysis

Objective: Dry eye disease (DED) is a prevalent ocular condition that significantly impacts quality of life. Umbilical cord serum (UCS) has emerged as a promising therapeutic option, but its efficacy requires further investigation. This systemic review and meta-analysis aimed to evaluate the therapeutic effects of UCS eye drops in the treatment of DED.
Methods: A comprehensive literature search was conducted across multiple databases, including PubMed, Web of science, Embase, Science Direct, Cochrane Library, and China National Knowledge Network, to identify relevant clinical trials. The efficacy of UCS was assessed based on key outcome measures, such as the ocular surface disease index (OSDI), tear break-up time (TBUT), Schirmer I test, and corneal fluorescein staining scores. Meta-analyses were performed to pool the results, and the findings were presented in a forest plot.
Results: Eight studies were included in the meta-analysis, with two relevant randomized controlled trials (RCTs) involving a total of 204 patients. Most of the included studies had a follow-up time of less than two months. The pooled results showed that UCS treatment significantly improved the OSDI, with a mean difference (MD) of -9.16 (95% CI, -12.0, -6.36) compared to baseline. Additionally, the TBUT values were higher in the UCS group, with an MD of 2.65 (95% CI, 0.93, 4.36). The Schirmer I test results showed an improvement, with an MD of 1.18 (95% CI, 0.30, 2.06). The fluorescein staining score were also lower in the UCS treatment group, with an MD of -4.71 (95% CI, -5.72, -3.69).
Conclusion: This meta-analysis suggests that UCS eye drops have a beneficial therapeutic effect on DED, significantly improving the OSDI, TBUT, Schirmer I test, and corneal fluorescein staining scores. However, larger RCTs with longer follow-up periods are needed to further evaluate the long-term efficacy and safety of UCS in the management of DED.