A determination of the current causes of hyperkalaemia and whether they have changed over the past 25 years

Hyperkalaemia is a potentially lethal electrolyte disorder. The objective of this study was to determine if the causes of hyperkalaemia-related visits to the emergency department (ED) have changed since 25 years.

All patients presenting to the ED with hyperkalaemia between January 2009 and August 2011 were included in this retrospective, single-centre study. Patients were divided into one of these three categories: mild (5·2≤ K(+)<5·8 mEq/l), moderate (5·8≤K(+)<7·0 mEq/l) or severe hyperkalaemia (K(+)≥7·0 mEq/l). The causes of hyperkalaemia were divided into three groups: renal failure (RF), potassium-increasing drugs (PIDs) or others.

Overall, 139 patients with hyperkalaemia were included in the study (mean K(+) of 6·2 mEq/l): 35% with mild, 49% with moderate and 16% with severe hyperkalaemia. Eighty-three per cent of patients (n = 115) had RF with creatinine levels ≥1·25 mg/dl or estimated glomerular filtration rate (eGFR) levels ≤60 ml/min/1·73 m(2). Serum potassium levels were significantly related with creatinine and eGFR values (P<0·001). The severity of hyperkalaemia was significantly related with creatinine levels ≥1·25 mg/dl (P = 0·002) and eGFR values ≤60 ml/min/1·73 m(2) (P = 0·005). Seventy-five per cent of patients (n = 105) were taking PIDs. Potassium levels were significantly related with PIDs (P<0·001), in particularly spironolactone (P = 0·001) and angiotensin-converting enzyme inhibitors (P = 0·008). The category 'others' included 7% of patients (n = 10).

RF (83%) and PIDs (75%) remain common causes of hyperkalaemia. Hyperkalaemia is significantly related with four variables: creatinine levels, spironolactone, ACEIs and beta-blocker intake. The causes of hyperkalaemia have not changed in recent years.