RESUMO
Our aim was to perform a meta-analysis to evaluate the possible link between diabetes and high levels of immunoglobulin M (IgM) antibodies against Gonadotropin-Releasing Hormone (GnRH). The search included PubMed, Web of Science, and Scopus databases. Inclusion criteria were any controlled clinical trials or observational studies that measured the level of IgM antibodies against GnRH hormone in diabetic patients, we excluded case reports, editorials, and animal studies. RevMan software, version 5.4 (The Cochrane Collaboration 2020) was used to perform the meta-analysis. Following the screening, three studies were included in the meta-analysis. The meta-analysis included 99 patients in the diabetes group and 318 healthy persons in the control group. The pooled effect showed no statistically significant association between diabetes and the prevalence of GnRH IgM antibodies compared with the control group (risk ratio {RR} = 1.64, 95% CI = 0.96 to 2.79, p-value = 0.03). The pooled effect showed a statistically significant association between diabetes and increased levels of GnRH IgM antibodies compared with the control group (mean difference {MD} = 2.13, 95% CI = 0.25 to 4.02, p-value = 0.03). Our study found a significant association between diabetes and increased levels of GnRH IgM antibodies. Therefore, GnRH IgM antibodies may play a role in the pathogenesis of diabetes or may be considered a unique immunological reaction in diabetic patients. More multicenter randomized studies are needed to support our results confirming the positive relationship between diabetes and high levels of IgM antibodies against GnRH hormone.
