title: Influence of Dietary Sodium and Potassium Intake on the Heart Rate Corrected-QT Interval in Elderly Subjects.
abstract: 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; 72.9±4.8 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.
authors.affiliation: Laboratory of Exercise Physiology, Faculty of Health and Sports Science, Fukuoka University.
authors.forename: Ryoma
authors.initials: R
authors.lastname: Michishita
authors.forename: Kazuko
authors.initials: K
authors.lastname: Ishikawa-Takata
authors.forename: Eiichi
authors.initials: E
authors.lastname: Yoshimura
authors.forename: Rikako
authors.initials: R
authors.lastname: Mihara
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ikenaga
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Morimura
authors.forename: Noriko
authors.initials: N
authors.lastname: Takeda
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Yamada
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Higaki
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Akira
authors.initials: A
authors.lastname: Kiyonaga
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D015992:Body Mass Index; D001835:Body Weight; D053840:Brugada Syndrome; D000075224:Cardiac Conduction System Disease; D002318:Cardiovascular Diseases / Q000209:etiology / Q000503:physiopathology; D004032:Diet; D004562:Electrocardiography; D004573:Electrolytes / Q000494:pharmacology; D005247:Feeding Behavior; D005260:Female; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology; D006329:Heart Conduction System / Q000002:abnormalities*; D006801:Humans; D008297:Male; D009752:Nutritional Status; D009765:Obesity / Q000150:complications; D011188:Potassium / Q000494:pharmacology*; D012982:Sodium, Dietary / Q000494:pharmacology*; D011795:Surveys and Questionnaires; D013851:Thinness / Q000150:complications
chemical_list: D004573:Electrolytes; D012982:Sodium, Dietary; D011188:Potassium