Electrocardiography changes in bipolar patients during long-term lithium monotherapy

• Published in: General hospital psychiatry 2014-11, Vol.36 (6), p.694-697
• Main Authors: Altinbas, Kursat, M.D, Guloksuz, Sinan, M.D., M.Sc, Caglar, Ilker Murat, M.D, Caglar, Fatma Nihan Turhan, M.D, Kurt, Erhan, M.D, Oral, Esat Timucin, M.D
• Format: Article
• Language: English
• Subjects: Adult; Adult and adolescent clinical studies; Antimanic Agents - administration & dosage; Antimanic Agents - adverse effects; Antimanic Agents - blood; Arrhythmia; Arrhythmias, Cardiac - chemically induced; Arrhythmias, Cardiac - diagnosis; Biological and medical sciences; Bipolar disorder; Bipolar Disorder - drug therapy; Bipolar disorders; Cardiac dysrhythmias; Cardiology. Vascular system; ECG; Electrocardiography - methods; Female; Heart; Humans; Lithium; Lithium Compounds - administration & dosage; Lithium Compounds - adverse effects; Lithium Compounds - blood; Male; Medical sciences; Middle Aged; Miscellaneous; Mood disorders; Neuropharmacology; Pharmacology. Drug treatments; Psychiatry; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer..., (alzheimer disease); Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Psychopharmacology; QT interval
• ISSN: 0163-8343; 1873-7714
• DOI: 10.1016/j.genhosppsych.2014.07.001

Abstract Objective Cardiovascular side effects of lithium have been reported to occur mainly at higher-than-therapeutic serum levels. We aimed to investigate the impact of the long-term lithium use on electrocardiogram (ECG) parameters in association with the serum levels in patients with bipolar disorder (BD) and in healthy controls (HCs) serving as the reference group. Methods The study sample consisted of 53 euthymic BD type I patients on lithium monotherapy at therapeutic serum levels ( M = 0.76, S.D.= 0.14, range=0.41–1.09 mmol/l) for at least 12 months and 45 HCs. A 12-lead surface ECG was obtained from all participants at resting state for at least half an hour for 5-min recording. Heart-rate, Pmax, Pmin, QRS interval, QT dispersion, QT dispersion ratio (QTdR) and Tpeak-to-end interval (TpTe) were measured. Results Regression analyses revealed that QTdR ( B = 14.17, P = .001), TpTe ( B = 18.38, P < .001), Pmax ( B = 17.84, P < .001) and Pmin ( B = 25.10, P < .001) were increased in BD patients who were on chronic lithium treatment than in HCs after controlling for age, sex and strict Bonferroni correction for multiple testing. There were no associations between serum lithium levels and ECG parameters. Conclusion Our findings suggest that the use of lithium is associated with both atrial and ventricular electrical instability, even when lithium levels are in the therapeutic range.