Influence of Dietary Sodium and Potassium Intake on the Heart Rate Corrected-QT Interval in Elderly Subjects

Abstract

Summary It is well known that imbalances in the dietary electrolytes are associated with a significantly higher incidence of cardiovascular disease (CVD). On the other hand, a prolonged heart rate corrected-QT (QTc) interval is associated with an increased risk of cardiac autonomic nervous system dysfunction, the incidence of CVD and sudden cardiac death. This study was designed to clarify the association between the nutritional status and the QTc interval in elderly subjects. The subjects included 119 elderly subjects (46 males and 73 females, age; 72.964.8 y) without a history of CVD, who were taking cardioactive drugs. Resting 12-lead electrocardiography was performed, while the QTc interval was calculated according to Bazett's formula. The nutritional status was assessed using a brief self-administered diet history questionnaire. The subjects were divided into three categories, which were defined as equally trisected distributions of the body mass index (BMI). The QTc interval was significantly longer in both the low and high BMI groups than in the moderate BMI group in both genders (p,0.05, respectively). A stepwise multiple regression analysis showed the QTc interval to be independently associated with the potassium intake in the low BMI group and the sodium intake in the high BMI group in both genders (p,0.05, respectively). These results suggest that the body mass, especially lean body mass and overweight, were associated with a prolonged QTc interval and dietary electrolytes in elderly subjects. Based on our results, we consider that it is necessary to perform dietary counseling, especially focusing on sodium and potassium intake, depending on the body mass.

Effect of serum electrolytes within normal ranges on QTc prolongation: a cross-sectional study in a Chinese rural general population

“…It would be inappropriate to suggest that they take potassium supplements to reduce the risk of QTc prolongation, which might lead to another risk status, namely, hyperkalaemia. Previous studies found that a low dietary potassium intake was independently associated with QTc prolongation [ 9 ], and a significantly higher incidence of cardiovascular disease and mortality [ 31 ]. Hence, it might be advisable to consume foods rich in potassium to reduce the risk of QTc prolongation.…”

“…Disturbances in serum electrolytes might induce or facilitate clinical arrhythmias by interacting with abnormal myocardial tissue, and this could even occur in a bundle of normal cardiac tissue. Furthermore, strong evidences has been found that identified hypokalaemia as a risk factor for QTc prolongation [ 8 ], and the dietary intake of potassium has also been independently associated with the QTc interval [ 9 ]. The same clinical studies also found that the concentrations of sodium, calcium and magnesium influence the QTc interval [ 7 , 10 , 11 ].…”

Factors that Contribute to the QTc Interval Prolongation in DR-TB Patients on STR Regimen

“…Abnormal ion transport may also occur in malnourished cells independent of absolute serum electrolyte concentrations (30) . Mischisita et.al was finding that the QTc interval was significantly longer in the low BMI groups compared to the moderate BMI group in both genders (31) . It has been well known that a prolonged QTc interval is reflected in the dysfunction of the cardiac autonomic nervous system, while the cardiac autonomic nervous system is influenced by eating disorders.…”

Elective lung resection increases spatial QRS-T angle and QTc interval

“…Female sex and older age predisposes QTc interval prolongation. Pathologically prolonged QTc has been noted in patients with electrolyte disturbances such as hypokalemia, hypomagnesemia and/or hypocalcemia, myocardial ischemia, heart failure and severe bradycardia [19,20,31]. Many medications can also result in asymptomatic or symptomatic QTc interval prolongation, their administration sometimes being associated with an increased risk for cardiac arrhythmias [22].…”

“…The corrected QT interval is an electrocardiographic parameter providing information on both cardiac depolarization and repolarization, especially the latter. Its prolongation has been observed in patients with electrolyte disorders and coronary diseases who are treated with antiarrhythmics or subjected to general anaesthesia with a volatile anesthetic [19][20][21]. A prolonged QTc interval has been well recognized as a parameter indicating an increased risk of malignant ventricular arrhythmias [22,23].…”