Beyond Healthcare Access: Social Deprivation and COVID-19 Outcomes in Dialysis Patients in the Provence-Alpes-Côte d’Azur Region, France

Background: Social inequalities are known to influence COVID-19 outcomes, primarily by limiting access to healthcare. However, dialysis patients in France benefit from a highly structured and fully covered medical follow-up, offering a unique setting to examine whether social deprivation remains a determinant of infection and severity, even when access to care is guaranteed. Objective: To assess the influence of socioeconomic deprivation on the prevalence and severity of COVID-19 in dialysis patients in the Provence-Alpes-Côte d’Azur (PACA) region, during the first year of the pandemic. Methods: We used data from the REIN registry to conduct a regional retrospective cohort study on dialysis patients from March to December 2020. Socioeconomic deprivation was measured using the French Deprivation Index (FDep). Multilevel logistic regression models were used to examine associations between deprivation and COVID-19 incidence and severity. Results: Dialysis patients living in areas with very high deprivation had a significantly higher risk of COVID-19 infection (OR = 1.48; 95% CI: 1.08–2.04). Among those infected, individuals living in unstable housing or in highly populated areas were more likely to develop severe forms. These associations persisted despite regular and uniform access to care. Conclusion: This study highlights a paradox: even in a population with guaranteed medical care, socioeconomic deprivation remains a key determinant of infection and severity. These findings suggest that social inequalities in health are not solely driven by healthcare access but also by broader structural factors. Addressing epidemic vulnerability therefore requires public health strategies that explicitly target social determinants of health.