Methods to evaluate renal function in elderly patients: a systematic literature review

Area of Science:

• Nephrology
• Geriatric Medicine
• Clinical Chemistry

Background:

• Prevalence of chronic renal failure in individuals aged 65+ varies significantly based on the glomerular filtration rate (GFR) estimation method.
• Accurate assessment of renal function is critical for managing elderly patients.
• Existing GFR calculation methods may not be universally applicable or accurate in the geriatric population.

Purpose of the Study:

• To systematically review and identify the optimal method for evaluating renal function in elderly patients applicable to clinical practice.
• To compare various GFR estimation methods against gold standard assays in the elderly population.

Main Methods:

• Systematic literature search conducted on PubMed and EMBASE databases.
• Inclusion criteria focused on studies using inulin, Cr-51-EDTA, Tc-DTPA, or iohexol assays as the gold standard for GFR measurement.
• Screening of articles by title, abstract, and five predefined criteria, with retained articles scored using an adapted QUADAS tool.

Main Results:

• Twelve articles met the inclusion criteria, focusing on populations aged 65 years and older.
• Significant heterogeneity was observed in study populations and statistical comparisons against gold standards.
• The Cockcroft-Gault (CG) equation, MDRD equation, and serum cystatin C concentration demonstrated the highest correlations with gold standard GFR measurements.

Conclusions:

• No single method was found to be definitively accurate for evaluating renal function in the elderly.
• Serum cystatin C, the CG formula, and the MDRD formula show potential utility but require further validation.
• Insufficient evidence currently supports the widespread clinical adoption of any specific method for GFR estimation in the elderly.