Hypokalaemia, CKD increase risk of sudden cardiac death in elderly hypertensive adults
In elderly hypertensive patients, serum potassium level, hypokalaemia and chronic kidney disease (CKD) appear to increase the risk of sudden cardiac death (SCD), a recent study has found.
Using data from 3,620 elderly hypertensive patients from three randomized clinical trials, researchers created a Bayesian network to analyse clinical and biological variables linked to cardiovascular disease. Among the variables of interest were serum potassium and creatinine, heart rate, and age and sex.
Of the participants, 81 died of SCD (mean age 78.0±6.7 years; 50.6 percent female) while 3,539 did not (mean age 76.0±4.8 years; 64.0 percent female). The overall incidence rate of SCD was 2.24 percent.
The Bayesian curve showed that five variables were most strongly linked to SCD: age, history of myocardial infarction, history of diabetes mellitus, serum potassium level and blood glucose. The corresponding area under the receiver operating characteristic curve of the model was 0.91.
Further analysis of the simulated data showed that renal failure (2.38 percent vs 2.07 percent; p<0.05), hypokalaemia (4.93 percent vs 2.16 percent; p<0.001) and hyperkalaemia (2.66 percent vs 2.16 percent; p<0.05) all significantly increased the risk of SCD.
Moreover, hypokalaemia and normal renal function (4.54 percent vs 2.00 percent; p<0.001), hypokalaemia and CKD (6.25 percent vs 2.00 percent; p<0.001), normal potassium and CKD (2.73 percent vs 2.00 percent; p<0.05), and hyperkalaemia and CKD (3.35 percent vs 2.00 percent; p<0.001) all elevated the probability of SCD relative to normal serum potassium and renal function.