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Published on: May 22, 2019
Renal reserve in the oldest old.
C G Musso1, J Reynaldi, B Martinez
1Nephrology Division, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina. carlos.musso@hospitalitaliano.org.ar
International Urology and Nephrology
|July 2, 2010
Summary
Renal reserve is preserved in healthy older adults, but its capacity to increase glomerular filtration rate diminishes with advanced age. This study investigated renal reserve in the very old, finding a significant age-related decline.
Area of Science:
- Gerontology
- Nephrology
- Renal Physiology
Background:
- Glomerular filtration rate (GFR) declines with age, impacting renal physiology in the elderly.
- Renal reserve (RR) measures the kidney's capacity to increase GFR by at least 20% after protein overload.
- Limited data exists on RR preservation in the very old (over 74 years).
Purpose of the Study:
- To investigate the preservation of renal reserve in healthy individuals aged over 74.
- To compare renal reserve across different age groups: young, old, and very old.
Main Methods:
- Studied 16 healthy individuals across three age groups: 20-40 (n=5), 64-74 (n=6), and >74 (n=5).
- Assessed renal reserve by measuring creatinine clearance with cimetidine before and after an oral protein load.
- Utilized ANOVA for statistical analysis.
Main Results:
- Renal reserve response was observed in all age groups.
- The magnitude of renal reserve (delta GFR) was significantly higher in young adults (103.6 ± 53 ml/min) compared to older adults (34.1 ± 40 ml/min).
- The very old group (>74) showed a significantly lower renal reserve (20.7 ± 0.7 ml/min) compared to both younger groups.
Conclusions:
- Renal reserve is preserved in healthy very old individuals.
- The magnitude of renal reserve significantly decreases with advancing age.
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