Society of Diabetic Nephropathy Prevention Journal of Nephropharmacology 2345-4202 14 1 2025 01 01 The effect of body mass index on estimated glomerular filtration rate in patients with IgA nephropathy; a systematic review and meta-analysis of the cohort studies e12712 e12712 10.34172/npj.2025.12712 EN Hossein Mardanparvar https://orcid.org/0000-0001-7455-5373 Hediyeh Mesbahi https://orcid.org/0009-0007-1102-3362 Sara Rasta https://orcid.org/0009-0002-5081-7935 Rasoul Jafari Arismani https://orcid.org/0000-0001-7440-0507 Sara Ghaseminejad Kermani https://orcid.org/0000-0002-1730-8437 Leila Jampour https://orcid.org/0009-0005-4183-7020 Alireza Amanollahi https://orcid.org/0000-0003-1056-5438 Farzaneh Barkhordari Ahmadi https://orcid.org/0009-0002-7895-5387 Nahid Moradi https://orcid.org/0000-0001-8629-5257 Mahin Roozitalab Journal Article 10.34172/npj.2025.12712 2024 06 09 2024 08 18 Introduction: The study is motivated by the growing concern surrounding chronic kidney disease worldwide and the need for early identification and effective management to slow or prevent kidney disease progression. To achieve this goal, we evaluated the correlation between body mass index (BMI) and estimated glomerular filtration rate (eGFR) in patients with IgA nephropathy through a systematic review and meta-analysis. Materials and Methods: The data were acquired after conducting a comprehensive exploration of the international databases of PubMed, Scopus, Web of Science, Cochrane, and the Google Scholar search engine until June 2024. The study heterogeneity was evaluated utilizing the I2 index. The data were scrutinized employing STATA 14, and a P value < 0.05 was considered significant. Results: Seven studies with a sample size of 1354 normal BMI people and 1020 obese or overweight patients were included in this meta-analysis. Based on the findings of the weighted mean difference (WMD), individuals who are overweight or obese had a lower eGFR (WMD = -7.34 [CI; -9.62, -5.05], P<0.001). Conclusion: The results demonstrated that the eGFR was significantly lower in obese or overweight people compared to individuals with normal BMI; therefore, we conclude that being overweight or obese may hurt kidney function. Registration: This study has been compiled based on the PRISMA checklist, and its protocol was registered on the PROSPERO (CRD42023417633) and Research Registry (UIN: reviewregistry1665) websites.