Effect of comorbidities on healthcare expenditures for patients on kidney replacement therapy considering the treatment modality and duration in a French cohort.

End-stage kidney disease (ESKD) is associated with a substantial economic burden. In France, the cost of care for such patients represents 2.5% of the total French healthcare expenditures but serves less than 1% of the population. These patients' healthcare expenditures are high because of the specialized and complex treatment needed as well as the presence of multiple comorbidities. This study aims to describe and assess the effect of comorbidities on healthcare expenditures (direct medical cost and non-medical costs including transportation and compensatory allowances) for patients with ESKD in France while considering the modality and duration of renal replacement therapy (RRT). This study included adults who started RRT for the first time between 2012 and 2014 in France and were followed for 5 years. Generalized linear models were built to predict mean monthly cost (MMC) by integrating first the time duration in the cohort, then patient characteristics and finally the duration of use of each treatment modalities. Comorbidities with the highest effect on MMC were inability to walk (+ 1435€), active cancer (+ 593€), HIV positivity (+ 507€) and diabetes (+ 396€). These effects vary according to age or treatment modalities. This study confirms the importance of considering patient characteristics, comorbidities and type of RRT when assessing healthcare expenditures for patients with ESKD.