The electrolyte disorder hyperkalemia, or high potassium, is a serious and potentially life-threatening condition. The kidneys, with the help of the hormones renin and aldosteron, maintain the balance of potassium in the body. As people age, the kidneys become less efficient due to loss of kidney mass and reduced blood flow. The elderly are more prone to hyperkalemia due to these age-related kidney changes in addition to medical conditions more common in older individuals.
The BC Endocrine Research Foundation notes that approximately 20 percent of people over age 65 will develop diabetes at some point in their life. Diabetes, combined with the age-related decrease in kidney function, can lead to a condition called hyporeninemic hypoaldosteronism, according to the article “Hyperkalemia in the Elderly” published in 1997 in the Journal of General Internal Medicine. This condition occurs when there is a disruption in secretion of the hormone renin, leading to high levels of potassium in the blood. Treatment can include a low potassium diet, using a medication called a loop diuretic, which increases potassium excretion, or medications that bind to potassium in the bowel.
High Dietary Potassium
Patients with high blood pressure often use salt substitutes. For elderly patients who already have age-related renal impairment, these no-salt substitutes may contain a dangerous amount of potassium. According to a 2002 article, “Drug-induced Hyperkalemia,” published in the American Journal of Medicine,” caution should also be used with low-sodium prepared meals. These meals use potassium chloride to replace salt, increasing the amount of potassium consumed and in turn increasing the risk of hyperkalemia.
ACE inhibitors are a class of medication prescribed for high blood pressure and congestive heart failure. Hyperkalemia is reported in 10 percent of patients on ACE inhibitors. These medications can decrease the secretion of aldosterone, according to the article “Drug-induced Hyperkalemia.” Patients with only modest age-related kidney insufficiency may develop hyperkalemia while on ACE inhibitors, and patients with heart failure are at even greater risk. Consuming a low potassium diet may help, although some patients may need to change medications.
The elderly commonly take nonsteroidal anti-inflammatory drugs (NSAIDs) for arthritis or muscle aches and pains. According to the article "Hyperkalemia in the Elderly," older patients take longer to clear NSAIDs from the body, resulting in increased concentrations of the drug metabolites. These metabolites can decrease the production of renin and aldosterone, leading to hyperkalemia. Additional high potassium risk factors for the elderly who use NSAIDs include dehydration, low dietary protein, congestive heart failure and some diuretic medications.