Reveal-ckd: prevalence of undiagnosed stage 3 chronic kidney disease in patients with diagnosed hypertension in canada

Objective: Hypertension is a risk factor for and complication of chronic kidney disease (CKD), a progressive condition affecting 11.1% of the global population. Early recognition and diagnosis of CKD is crucial for effective management to slow disease progression and improve patient outcomes. This REVEAL-CKD study assessed the prevalence of, and factors associated with, undiagnosed stage 3 CKD in patients with hypertension. Design and method: REVEAL-CKD is an observational study using secondary data from electronic medical records (EMR) and claims data. Data were extracted from the Canadian Primary Care Sentinel Surveillance Network (CPCSSN) database, that consists of primary care EMR data from approximately 1,500 general practice clinicians across eight provinces and one territory of Canada. The study cohort included patients aged at least 18 years with two consecutive estimated glomerular filtration rate (eGFR) values 30-59 mL/min/1.73m 2 recorded 91-730 days apart between 2015-2021. The date of the second qualifying eGFR was the index date. Included patients were required to have hypertension diagnosis code before index. Patients with no CKD diagnosis code before and up to 6 months after index were considered undiagnosed. This study was granted approval by the CPCSSN data access committee (project number: 2022SRE147). Results: Of the 45,914 patients meeting the study inclusion criteria for stage 3 CKD, median age at index date was 77 years (interquartile range [IQR]: 69-84 years) and 19,597 (42.7%) were male. Of these patients, 32,192 (70.1%) also had an existing diagnosis of hypertension. Among patients meeting the criteria for stage 3 CKD and having a diagnosis of hypertension there were 30,523 patients, (94.8%) who did not have a recorded diagnosis of CKD up to 6 months after index. Of these patients, only one fifth was diagnosed with CKD after 4 years. Conclusions: A large proportion of patients in Canada with hypertension and stage 3 CKD do not have a recorded CKD diagnosis, and there is substantial diagnostic delay despite clinical evidence. This likely results in patients not receiving guideline-directed management to reduce the risk of disease progression and adverse clinical outcomes that could have been avoided by early detection of CKD.