title: Lithium concentration correlates with QTc in patients with psychosis.
abstract: QT prolongation induced by antipsychotics has been reported to be a determinant for the development of torsade de pointes and sudden death. However, the effect of lithium on QT interval has not been fully clarified. The aim of the present study was to elucidate the relationship between serum lithium concentration and QT interval in patients treated with lithium. We examined serum lithium concentrations and electrocardiographic features in 39 inpatients with bipolar affective disorder or schizophrenia. The longest QT interval in the 12 electrocardiographic leads was measured using GE Marquette QT guard System Software, and Bazett formula was used for heart rate correction. The longest QTc was positively correlated with lithium concentration ( r = 0.46, P = .003). Multiple regression analysis revealed that sex (female, P = .037), lower serum K + concentration ( P = .029), and especially, higher serum lithium concentration ( P = .009) were determinants for the prolongation of the QTc.
authors.affiliation: Department of Clinical Researh, Hizen psychiatric Center, Saga, 842-0192 Japan. mamiya@hizen2.hosp.go.jp
authors.forename: Kohsuke
authors.initials: K
authors.lastname: Mamiya
authors.forename: Tsuneaki
authors.initials: T
authors.lastname: Sadanaga
authors.forename: Atsuko
authors.initials: A
authors.lastname: Sekita
authors.forename: Yoriko
authors.initials: Y
authors.lastname: Nabeyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yao
authors.forename: Eiji
authors.initials: E
authors.lastname: Yukawa
mesh_terms: D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D006801:Humans; D008094:Lithium / Q000097:blood* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000188:drug therapy*; D012044:Regression Analysis; D012559:Schizophrenia / Q000097:blood / Q000188:drug therapy; D012737:Sex Factors
chemical_list: D008094:Lithium