20 years of real-world data to estimate chronic kidney disease prevalence and staging in an unselected population

Lay Summary This is the first real-world-based study to characterize the prevalence of chronic kidney disease (CKD) in a large, unselected Portuguese population. CKD represents a major global public health problem affecting nearly 700 million persons and contributing to the development of related disorders, including hypertension, obesity and type 2 diabetes mellitus. Fortunately, the development of CKD comorbidities can be delayed or prevented if rapidly detected at early stages. We studied the CKD prevalence in adult users of the primary, secondary and tertiary healthcare units of an integrated health region in northern Portugal and we fully characterized CKD staging by demographic, clinical, analytical and echocardiographic data. The overall estimated prevalence of CKD was 9.8% and was higher in females (5.5%) than males (4.2%). It probably provides the nearest estimate of the true CKD prevalence and may help healthcare providers to guide CKD-related policies and strategies focused on prevention and on the improvement of cardiovascular disease and other outcomes. Chronic kidney disease (CKD) represents a global public health burden, but its true prevalence is not fully characterized in the majority of countries. We studied the CKD prevalence in adult users of the primary, secondary and tertiary healthcare units of an integrated health region in northern Portugal (n = 136 993; representing similar to 90% of the region's adult population). Of these, 45 983 (33.6%) had at least two estimated glomerular filtration rate (eGFR) assessments and 30 534 (22.2%) had at least two urinary albumin:creatinine ratio (UACR) assessments separated by at least 3 months. CKD was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines as a persistent decrease in eGFR (<60 ml/min/1.73 m(2)) and/or an increase in UACR (>= 30 mg/g). The estimated overall prevalence of CKD was 9.8% and was higher in females (5.5%) than males (4.2%). From these, it was possible to stratify 4.7% according to KDIGO guidelines. The prevalence of CKD was higher in older patients (especially in patients >70 years old) and in patients with comorbidities. This is the first real-world-based study to characterize CKD prevalence in a large, unselected Portuguese population. It probably provides the nearest estimate of the true CKD prevalence and may help healthcare providers to guide CKD-related policies and strategies focused on prevention and on the improvement of cardiovascular disease and other outcomes.