Hallan SI et al. (2006) Screening strategies for chronic kidney disease in the general population: follow-up of cross sectional health survey. BMJ 333: 1047–1050

Screening for chronic kidney disease (CKD) is currently performed routinely in patients with hypertension and diabetes, but there might be a need for more-widespread screening. Hallan et al. compared CKD screening strategies using data from a Norwegian population-based health study involving 65,604 individuals aged ≥20 years between 1995 and 1997. Participants completed a questionnaire, underwent a clinical examination and were observed through central registries until 30 June 2004, or until end-stage renal disease or death.

Restricting screening to individuals known to have hypertension or diabetes mellitus identified only 44.2% of stage 3–5 CKD cases, with 5.9 screenings necessary to identify one case. Expanding the screening strategy to include other risk factors for CKD (previous cardiovascular disease, obesity, smoking and family history of hypertension or diabetes) increased the CKD detection rate to 81.4%, but required 19.1 screenings to detect one case. Screening individuals aged >55 years or with diabetes or hypertension identified 93.2% of cases, with 8.7 screenings needed to identify one case. Using US K/DOQI guidelines to delimit the screening strategy identified 89.3% of cases, but UK CKD guidelines detected just 60.9% of cases; both strategies required about nine screenings to detect one case. ISN guidelines recommend screening all patients who visit their doctor, which should identify all CKD cases, but would require 20 screenings to detect one case.

Adding age >55 years to a strategy of screening patients with hypertension or diabetes greatly increases the number of CKD cases identified while requiring few additional screenings. Further study is needed of the cost-effectiveness of screening, however, before recommendations can be made.