ABSTRACT
I. RENAL PHYSIOLOGY AND AGING A. Clinical Relevance The kidney undergoes several age-related anatomical and physiological changes that are associated with a greater susceptibility toward the development of specific electrolyte and acid-base disturbances. In particular, advancing age is associated with a decline in glomerular filtration rate (GFR) and an impaired ability to maintain water, sodium, potassium, and acid-base homeostasis in response to exogenous stimuli. Some of these renal changes are due to degenerative cardiovascular processes and a subsequent functional reduction in renal perfusion, whereas others reflect intrinsic alterations in renal function. It is important that the clinician be aware of not only subtle alterations that may occur in the baseline electrolyte and acid-base settings but also more importantly the blunted response to disease processes, environmental conditions, and commonly used medications. A greater understanding of the alterations in renal physiological and related neurohormonal responses that occur with aging can help guide the clinician toward a more timely and appropriate response to a given disease process.
