Marcussen M, et al. - In patients co-treated with antipsychotic and diuretic drugs, researchers analyzed the association between serum potassium levels and risk of all-cause mortality. They identified patients between 1995 and 2012 who received a combination of an antipsychotic and a diuretic drug and who further had a serum potassium measurement within 90 days using a register-based cohort design. Findings revealed that hyperkalemia, hypokalemia, and high normal potassium levels were correlated with an increased risk of 6-month all-cause mortality. The present data indicated that excess mortality in patients co-treated with antipsychotic and diuretic drugs was associated with serum potassium levels, independent of antipsychotic drugs.