Diagnostic Yield of Various Serum Creatinine Testing Frequencies in People at Risk for CKD

Area of Science:

• Nephrology
• Public Health
• Clinical Diagnostics

Background:

• Current guidelines recommend regular serum creatinine testing for individuals with diabetes or hypertension to screen for chronic kidney disease (CKD).
• However, the optimal frequency for this testing remains undetermined.
• This study investigates the diagnostic yield of varying testing frequencies for incident CKD.

Purpose of the Study:

• To determine the diagnostic yield of incident chronic kidney disease (CKD) based on different testing frequencies (every 2, 3, 4, or 5 years) compared to annual testing.
• To assess how age, sex, comorbidities, albuminuria, and a CKD risk score influence the diagnostic yield of serum creatinine testing.

Main Methods:

• A retrospective population-based cohort study was conducted involving 3,515,163 adults in Alberta, Canada, with an initial estimated glomerular filtration rate (eGFR) above 60 mL/min/1.73m2.
• The study assessed the diagnostic yield for incident CKD (defined by ≥2 eGFR measures <60 mL/min/1.73m2) across various testing intervals.
• Analyses were stratified by demographic factors and clinical risk indicators.

Main Results:

• The number of tests needed to detect one new CKD case annually was substantially higher in younger individuals (<50 years) compared to older adults (>70 years).
• Testing frequency significantly impacted diagnostic yield across different risk groups, with higher yields in those with diabetes, hypertension, or heart failure.
• Reducing testing frequency for individuals with diabetes or hypertension to every three years could delay diagnoses but avert millions of laboratory assays annually.

Conclusions:

• The frequency of serum creatinine testing should be individualized based on patient age and the presence of other CKD risk factors.
• Tailoring testing intervals can optimize the detection of incident CKD while reducing unnecessary laboratory utilization.
• This personalized approach enhances diagnostic efficiency and potentially lowers healthcare costs.