title: Electrolyte disorders in the elderly.
abstract: Normal human ageing impairs homeostatic mechanisms in such a way as to exaggerate and prolong the effects of stress. Thus, an event--pathological or traumatic--which produces a trivial change in plasma electrolytes of young people may produce major oscillations of plasma levels in the elderly, which take much longer to return to 'normal levels'. This is especially apparent with perturbations in the plasma levels of sodium and potassium, mainly due to changes in renal function and neurohumeral mechanisms which occur with increasing age. Paradoxically this does not mean that the clinician should be over-enthusiastic in attempting to correct electrolyte imbalance because, for the same reasons, the danger of over-treatment producing the opposite and equally dangerous electrolyte imbalance is ever-present. Indeed, in clinical practice most electrolyte disturbances in old age are iatrogenic in origin. Cautious patience and vigilance should be the clinical approach with elderly patients. A high index of suspicion should lead to a careful appraisal of the drug (diuretic, intravenous fluid) and environmental (dehydration) aetiology of most electrolyte disturbances in old age.
mesh_terms: D000368:Aged; D000375:Aging; D001127:Arginine Vasopressin / Q000378:metabolism; D004327:Drinking Behavior / Q000502:physiology; D005919:Glomerular Filtration Rate; D006706:Homeostasis; D006801:Humans; D006947:Hyperkalemia / Q000209:etiology; D006955:Hypernatremia / Q000209:etiology; D007008:Hypokalemia / Q000209:etiology; D007010:Hyponatremia / Q000209:etiology; D007668:Kidney / Q000473:pathology / Q000502:physiology; D007671:Kidney Concentrating Ability; D011188:Potassium / Q000378:metabolism; D012079:Renal Circulation; D012083:Renin / Q000097:blood; D012964:Sodium / Q000378:metabolism; D014883:Water-Electrolyte Imbalance / Q000209:etiology*
chemical_list: D001127:Arginine Vasopressin; D012964:Sodium; D012083:Renin; D011188:Potassium