The impact of cardiovascular disease and type 2 diabetes mellitus on social cost in chronic kidney disease patients in Italy

OBJECTIVES: Chronic kidney disease (CKD) is leading condition of several comorbidities with additional social economic burden. The study aims to estimate the economic impact of cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) on the social cost of a patient with CKD (stage IV and V pre-dialyses) in Italy. METHODS: All adult outpatients in charge of 14 main Hospitals Centers in Tuscany Region have been enrolled during 7 weeks in the cross sectional study. Direct medical costs have been estimated using tariffs for laboratory test, diagnostic exams, visits and hospitalization and price for drugs. Non medical costs included the cost of diet, patients and caregivers travel expenses, domestic help and informal care. The loss of productivity of patients and caregivers have been estimated as indirect costs using the human capital approach. The incremental effects of having comorbidities on social cost of CKD were estimated by multivariate Generalized Linear Models (log link, Gamma family) adjusting for gender, age and stage of CKD. Costs are expressed in Euro 2012. RESULTS: Among 484 CKD patients enrolled, CVD and T2DM have been found respectively in 214 (44%) and 171 (35%) patients. The raw estimated mean annual social costs were €11,375 (± €7,480) per patient with CKD-CVD and €11,627 (± €7,657) per patient with CKD-T2DM. Direct non medical costs and indirect costs accounted respectively for 31% and 23% of social cost for CKD-CVD and 30% and 22% for CKD-T2DM. The incremental effects of having comorbidities on the overall social cost of CKD were €2,928 (95% CI: €1,680-€4,176, p=0.000) for CVD and €2,640 (95% CI: €1,301-€3,979, p=0.000) for T2DM. CONCLUSIONS: CVD and T2DM significantly increase the social cost of CKD due to the rise of the medical component. However the burden of the disease is mainly sustained by patients, their families and the productivity system.