Prevalence of chronic kidney disease in the community in the United Kingdom in OxRen, a population-based cohort study

BackgroundChronic kidney disease (CKD) is a largely asymptomatic condition of diminished renal function which may not be detected until advanced stages without screening. 
AimTo establish undiagnosed and overall CKD prevalence using a cross-sectional analysis.
Design and settingLongitudinal cohort study in UK primary care.
MethodsParticipants aged over 60 years were invited to attend CKD screening visits to determine whether they had reduced renal function, (estimated glomerular filtration rate [eGFR] <60ml/min/1.73m2 or albumin:creatinine ratio ≥3mg/mmol). Those with existing CKD, low eGFR or evidence of albuminuria or two positive screening tests attended a baseline assessment (CKD cohort).
ResultsA total of 3207 participants were recruited and 861 attended the baseline assessment. The CKD cohort consisted of 327 people with existing CKD, 257 people with CKD diagnosed through screening (CKD prevalence of 18.2%, 95%CI 16.9-19.6), and 277 with borderline/transient decreased renal function. In the 861-participant CKD cohort, 54.4% were female, mean±SD age was 74.0±6.9 years and mean eGFR was 58.1±18.4 ml/min/1.73m2. Of the 584 with confirmed CKD, 44.0% were diagnosed through screening. Over half the CKD cohort (447/861) fell into CKD stages 3-5 at their baseline assessment, giving an overall prevalence of CKD stages 3-5 of 13.9% (n=3207, 95%CI 12.8-15.1).
ConclusionsThis study found that around 44% of people living with CKD are undiagnosed without screening and prevalence of CKD stages 1-5 was 18.2% in this over 60s population . Follow-up will provide data on annual incidence, rate of CKD progression, determinants of rapid progression and predictors of cardiovascular events.