Prevalence of hypokalemia in older persons: results from the PolSenior national survey

Key summary pointsAim To examine what is the prevalence of hypokalemia in the older population. Findings The prevalence of hypokalemia was similar in older persons and younger ones. Hypokalemia is more often found in patients with arterial hypertension treated with diuretics. Oral supplementation of potassium in these patients did not prevent hypokalemia. Message In older persons, diuretic treatment is the most important cause of hypokalemia. Prevention of hypokalemia with the use of oral potassium supplementation is in this population insufficient. Purpose Hypokalemia is one of the most common electrolyte disturbances in clinical practice. There are only a few epidemiological studies analyzing the occurrence of hypokalemia in older persons. The aim of the study was to determine the prevalence of hypokalemia in the Polish older population. Methods Serum potassium concentration was estimated in 4654 participants (2270 females and 2384 males, mean age 76.5 [11.0] years), who participated in the PolSenior study. Hypokalemia was defined as serum potassium concentration below 3.5 mmol/L. Hypokalemia was found in 39 participants (0.84%) and was significantly more frequent among females (28 females = 1.23% and 11 males = 0.46%; p = 0.003). The prevalence of hypokalemia was not related to age. Among 3303 participants suffering from arterial hypertension, 1093 were treated with potassium-losing diuretics. Results Hypokalemia was significantly more frequent among hypertensive than normotensive older participants (1.06 vs. 0.30% respectively; p = 0.007) and among hypertensive participants treated with potassium losing diuretics than ones untreated with these drugs (1.96 vs. 0.46% respectively; p < 0.001). In hypertensive participants, the prevalence of hypokalemia did not depend significantly on oral supplementation of potassium (1.92 and 0.98% respectively, NS). None of 81 participants using laxative agents presented hypokalemia. Conclusions This study demonstrates that: older age seems not to appear to be a significant risk factor of hypokalemia. Hypokalemia is more often found in the older hypertensive patients treated with potassium losing diuretics, and prevention of diuretic-induced hypokalemia with oral supplementation of potassium seems to be insufficient.