Does routine estimated glomerular filtration rate reporting adversely affect medication dosing in an older...

Area of Science:

• Nephrology
• Clinical Pharmacology
• Geriatric Medicine

Background:

• Historically, Cockcroft-Gault (CG) estimated creatinine clearance (eCrCl) guided drug dosing in renal impairment.
• Current standard pathology reports primarily provide estimated glomerular filtration rate (eGFR).
• Discrepancies between eCrCl and eGFR may impact medication safety in elderly patients.

Purpose of the Study:

• To investigate the frequency of drug dosing errors in patients aged ≥65 years when using eGFR versus eCrCl.
• To determine if the use of CKD-EPI eGFR, compared to CG eCrCl, contributes to prescribing errors.

Main Methods:

• Single-centre retrospective cohort study.
• Inclusion of 162 patients aged 65 years and older.
• Analysis of over 200 medications requiring GFR-based dose adjustment.

Main Results:

• Approximately 12.5% of medications had potential prescribing errors, irrespective of the GFR estimation method used.
• The use of CKD-EPI eGFR explained only a small proportion of these potential errors compared to CG eCrCl.
• No clinical consequences were observed due to the discrepancies between eGFR and eCrCl in this cohort.

Conclusions:

• Potential drug dosing errors are prevalent in elderly patients with kidney disease, irrespective of the estimation method (eGFR or eCrCl).
• The shift from CG eCrCl to CKD-EPI eGFR is not a major driver of these prescribing errors.
• Clinical monitoring remains crucial for safe medication management in this population.