Healthcare resources and differences in kidney disease-related mortality in Italy: a longitudinal study

Background: Significant differences in kidney disease-related mortality persist among Italian regions, even after adjusting for age and education level, suggesting a role of contextual factors. The study aimed to assess whether these differences are attributable to the availability of economic and structural resources for healthcare. Methods: Retrospective longitudinal cohort study conducted on the Italian population recorded in the 2011 Census and followed up to 2019. Deaths from kidney diseases were retrieved by record linkage with the Causes of Death Register. Regional information on age-adjusted prevalence of kidney disease (indicator of demand for care), current healthcare expenditure per capita, and number of nurses and beds in dialysis units (indicators of renal care supply) per million residents were selected as contextual variables. Regional differences in kidney disease-related mortality taking or not into account these contextual indicators were evaluated using a multilevel approach. Results: Age-adjusted kidney disease-related mortality rates were higher than the national average for males and females in the largest southern regions. When adding to the models the prevalence of kidney disease, healthcare expenditure, and number of nurses and beds in dialysis units, regional differences in kidney disease-related mortality became non-significant compared to the national average. Significant heterogeneity persisted across regions, both in males and females, although its magnitude strongly decreased when regional-level covariates were considered. Conclusions: Regional differences in kidney disease-related mortality decreased markedly after considering the general expenditure for healthcare and the number of nurses in dialysis units, suggesting that resources dedicated to caring for kidney disease patients may play an important role in decreasing their mortality.