BACKGROUND: Studies exploring the correlation between Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) and the increased risk of chronic kidney disease (CKD) from a country-specific perspective have been limited. This study addresses regional variations and the role of the Socio-Demographic Index (SDI) in this relationship. METHODS: This analysis integrates MASLD and country-level CKD data from the Global Burden of Disease study 2021. To evaluate the relationships between MASLD and CKD incidence, mixed-effects linear regression models that account for country-level random effects were employed. This analysis was adjusted for median age, percentage of males, SDI, and metabolic risk factors. RESULTS: The incidence of MASLD and CKD demonstrated a similar regional distribution, with the highest of MASLD and CKD occurring in North Africa and the Middle East. After adjusting for age, gender, systolic blood pressure, fasting plasma glucose, body mass index, and SDI, a higher incidence of MASLD was associated with an increased incidence of CKD (p <
0.001), with MASLD incidence accounting for 53.0% of the explained variance in CKD incidence. Additionally, SDI, demographic variables (median age, population of male) and metabolic risks (High SBP, FPG and BMI), were responsible for 10.4%, 6.3%, and 30.3% of the explained variance in CKD incidence, respectively. Different patterns emerged in this association according to SDI status. In low SDI countries, significant associations were observed between increasing MASLD incidence rates and higher CKD incidence (p = 0.007), whereas in high SDI countries, no significant associations were found between MASLD and CKD incidence (p = 0.106). CONCLUSIONS: Our findings reveal a geographical correlation between MASLD and CKD incidence, contingent upon socioeconomic factors. To effectively mitigate the global burden of MASLD and CKD, it is imperative to design and implement targeted public health strategies that consider the unique socioeconomic contexts of each region, thus fostering equitable health outcomes.