title: Risk of QTc prolongation in a cohort of opioid-dependent HIV-infected patients on methadone maintenance therapy.
abstract: BACKGROUND
  Concern regarding the QTc interval in human immunodeficiency virus (HIV)-infected patients has been growing in recent years, and cases of prolonged QTc interval and torsades de pointes have been described in HIV-infected patients on methadone therapy. This study aimed to determine the prevalence and factors associated with long QTc interval in a cohort of opioid-dependent HIV-infected patients on methadone maintenance therapy.
  
  
  METHODS
  A cross-sectional study was conducted in opioid-dependent HIV-infected patients on methadone maintenance therapy at a drug abuse outpatient center. Patients with any cardiac disease, drug-positive urine test, electrolyte abnormalities, and changes in their antiretroviral therapy (ART) or methadone doses in the last 2 months were excluded. Heart rate and QT interval in lead II were measured using the Bazett formula.
  
  
  RESULTS
  Ninety-one patients were included: 58 (63.7%) were men with a median age of 44.5 years and 68 of 91 (74.7%) were on ART. Median methadone dose was 70 mg/day (range 15-250 mg/day) and mean QTc interval was 438 ± 34 ms. Prolonged QTc interval (>450 ms) was documented in 33 of 91(36.3%) patients, and 3 of 91 (3.2%) had QTc >500 ms. On multiple linear regression analysis, methadone doses (P = .005), chronic hepatitis C-induced cirrhosis (P = .008), and being ART-naive (P = .036) were predictive of prolonged QTc.
  
  
  CONCLUSIONS
  The prevalence of prolonged QTc interval in opioid-dependent HIV-infected patients on methadone maintenance therapy is high. Risk factors for prolongation of the QTc interval are chronic hepatitis C-induced cirrhosis, higher methadone doses, and being ART-naive. Thus, electrocardiographic monitoring is required to minimize cardiovascular morbidity and mortality in this specific HIV group.
authors.affiliation: Department of Internal Medicine.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Vallecillo
authors.forename: Sergio
authors.initials: S
authors.lastname: Mojal
authors.forename: Albert
authors.initials: A
authors.lastname: Roquer
authors.forename: Diana
authors.initials: D
authors.lastname: Martinez
authors.forename: Paola
authors.initials: P
authors.lastname: Rossi
authors.forename: Francina
authors.initials: F
authors.lastname: Fonseca
authors.forename: Roberto
authors.initials: R
authors.lastname: Muga
authors.forename: Marta
authors.initials: M
authors.lastname: Torrens
mesh_terms: D000328:Adult; D018791:CD4 Lymphocyte Count; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000453:epidemiology* / Q000503:physiopathology*; D006801:Humans; D016014:Linear Models; D008133:Long QT Syndrome / Q000150:complications / Q000453:epidemiology / Q000821:virology*; D008297:Male; D008691:Methadone / Q000627:therapeutic use*; D008875:Middle Aged; D015999:Multivariate Analysis; D058850:Opiate Substitution Treatment; D009293:Opioid-Related Disorders / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology*
chemical_list: D008691:Methadone
keywords: HIV; QTc prolongation; methadone; opioid dependence