title: Elevation of QT dispersion after obesity drug sibutramine.
abstract: BACKGROUND
  QT dispersion (QTd) is an arrhythmia parameter that can be used to assess homogeneity of cardiac repolarization. An antiobesity drug sibutramine is linked with several cardiovascular adverse events, including arrhythmias. Previous studies showed that sibutramine may prolong the QT interval and may be associated with cardiac arrest.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the effect of sibutramine on QTd.
  
  
  METHODS
  The study group consisted of 65 consecutive patients with obesity. All patients were to receive 15 mg of sibutramine once a day in addition to standard care for lifestyle change. Twelve-lead ECG was performed before the onset of the medication and after 16 weeks of treatment. QTd was calculated.
  
  
  RESULTS
  Three individuals were withdrawn from the study because of the adverse effects of sibutramine. Sixty-two patients with obesity were recruited into the study. All patients were women (62, 100%). Body weight (106.3 ± 15.0 kg vs. 101.6 ± 16.9 kg, P < 0.001) and low-density lipoprotein cholesterol (128.4 ± 29.7 mg/dl vs. 111.6 ± 24.6 mg/dl, P < 0.001) levels were significantly decreased whereas QTd (46.1 ± 22.6 ms vs. 53.7 ± 16.7 ms, P = 0.026) was significantly increased after 16 weeks of sibutramine treatment. The increase in QTd was not correlated with the decrease in body weight. There was no correlation between QTd and any conditions such as diabetes or hypertension.
  
  
  CONCLUSIONS
  This study has shown an elevation in QTd, which may lead to cardiac arrhythmias, after sibutramine treatment. Molecular mechanisms may play role in increasing QTd. Further randomized studies are needed to clarify cardiac adverse events of the sibutramine.
authors.affiliation: Department of Cardiology, Kecioren Teaching and Research Hospital, Kecioren, Ankara, Turkey.
authors.forename: Ahmet A
authors.initials: AA
authors.lastname: Yalcin
authors.forename: Bunyamin
authors.initials: B
authors.lastname: Yavuz
authors.forename: Derun T
authors.initials: DT
authors.lastname: Ertugrul
authors.forename: Beyza
authors.initials: B
authors.lastname: Algul
authors.forename: Hamiyet
authors.initials: H
authors.lastname: Yilmaz
authors.forename: Onur S
authors.initials: OS
authors.lastname: Deveci
authors.forename: Metin
authors.initials: M
authors.lastname: Kucukazman
authors.forename: Naim
authors.initials: N
authors.lastname: Ata
authors.forename: Gokhan
authors.initials: G
authors.lastname: Demirel
authors.forename: Kursat
authors.initials: K
authors.lastname: Dal
authors.forename: Emre
authors.initials: E
authors.lastname: Tutal
mesh_terms: D000328:Adult; D019440:Anti-Obesity Agents / Q000009:adverse effects*; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000503:physiopathology; D031204:Caloric Restriction; D003131:Combined Modality Therapy; D003503:Cyclobutanes / Q000009:adverse effects*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects* / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy / Q000188:drug therapy* / Q000503:physiopathology; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014421:Turkey
chemical_list: D019440:Anti-Obesity Agents; D003503:Cyclobutanes; C058254:sibutramine