Costs and Consequences of Chronic Kidney Disease in People with Diabetes in Portugal: A Modelling Study

Introduction: Chronic kidney disease is the fastest-growing chronic disease in terms of prevalence and one of the biggest causes of global mortality according to the Global Burden of Disease Collaboration. This study aimed to project the natural disease progression of this disease in people with diabetes, and to quantify the costs and consequences in the Portuguese context. This was achieved by developing an analytical model reflecting the epidemiology of chronic kidney disease and integrating the various stages of disease progression. Methods: A population-based cohort Markov model was used, to follow an adult cohort of people with diabetes and chronic kidney disease as they progressed through different risk categories, in annual cycles, over a period of 50 years. The model considered the natural progression of chronic kidney disease through 18 risk categories based on the KDIGO classification system, as well as the probability of patients receiving renal replacement therapy, including dialysis and kidney transplantation, and the probability of death. Each stage is associated with an annual cost and a disability weight, so the model allowed survival, years lived with disability and lifetime costs to be estimated for the entire population with chronic kidney disease and for patients in different risk categories. Results: Over the cohorts lifetime, the model estimated, for the total population with chronic kidney disease and diabetes, an average survival of 8.62 years, with 0.59 years lived with disability, and an average cost of 24 613. These figures correspond to a loss of more than 410 000 years lived with disability and a total lifetime cost of 17.0 billion euros. The progression of this disease was associated with lower survival, more years lived with disability and higher costs. Conclusion: The results of this study characterize the natural progression of chronic kidney disease in people with diabetes mellitus type 2, as well as the associated costs and consequences in the national context. Since diabetes mellitus type 2 is a risk factor for chronic kidney disease, it is expected that the real impact will be greater than estimated in the coming decades. Analysis by risk level shows that progression of the disease is associated with worse outcomes.