Epidemiology of chronic kidney disease in young patients in developing countries

BACKGROUND Chronic kidney disease (CKD) is an important but under-recognized cause of morbidity in young people living in low- and middle-income countries (LMICs), where epidemiological data in this age group are limited and fragmented. LMICs, as defined by the World Bank, have a gross national income per capita between United States dollar 1136 and United States dollar 13845 (2024). AIM To summarize the prevalence of CKD among individuals aged ≤ 25 years in LMICs and to explore sources of between-study variability. METHODS We performed a systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. PubMed, EMBASE, Cochrane Library, and Google Scholar were searched for original studies reporting CKD prevalence in LMIC populations aged 0-25 years. Study-level proportions were pooled using a random intercept logistic regression model (generalized linear mixed model) with logit transformation. Heterogeneity was quantified using τ 2, I 2, and Q statistics. Prespecified subgroup analyses stratified studies by world region and study setting (community-based, hospital/clinic-based, CKD/end-stage renal disease registries, and specific disease cohorts). Random-effects meta-regression examined the contribution of region and setting to heterogeneity. Sensitivity analyses excluding registry and high-risk cohorts were undertaken to approximate prevalence in more general populations. RESULTS Nineteen studies from 17 countries (339940 participants; 96674 CKD cases) were included. The overall pooled prevalence was 11.7% (95% confidence interval: 5.5%-23.3%), with a prediction interval spanning 0.3%-84% and extreme heterogeneity (τ 2 = 3.41; I 2 = 99.9%). Subgroup analyses showed a clear gradient by setting, from lowest prevalence in community-based samples to highest in registries and disease-specific cohorts. Meta-regression indicated that setting explained 36.8% and region 28.2% of between-study variance, while both combined explained 61.4%. In sensitivity analyses restricted to more general populations, pooled prevalence was in the 4%-5% range (random-effects 95% confidence interval: 2%-9%), although heterogeneity remained high. CONCLUSION CKD in young people in LMICs is common and highly variable, largely reflecting differences in study setting and geography, and warrants targeted early detection and surveillance strategies.