Role of antiretroviral treatment in prolonging QTc interval in HIV-positive patients.

The aims of our study were to assess the prevalence of QTc prolongation in a group of HIV-infected individuals and to evaluate the associated risk factors.All the 650 HIV-infected patients followed up at our outpatient clinic underwent ECG recording. A "nested" case-control study was performed using as cases 64 HIV-infected patients with QTc > 0.44 s and as controls (1:4) 256 HIV-positive subjects matched by gender and age with QTc interval < or = 0.44 s.A prolonged QTc interval was found in 9.8% of HIV-positive individuals (64/650). In the nested case-control study, an increased risk of having a prolonged QTc interval was observed among patients taking nelfinavir, efavirenz, methadone, cotrimoxazole or an excessive amount of alcohol. When a zidovudine (AZT)-containing backbone was associated with nelfinavir-based or efavirenz-based antiretroviral therapy, the risk of having a prolonged QTc interval was about three times higher than in patients taking nelfinavir or efavirenz without AZT.Several drugs administered to HIV-infected patients may cause a QTc interval prolongation increasing the risk of serious arrhythmias. An ECG follow-up for the assessment of QTc seems to be advisable for HIV-infected patients receiving drugs with a QTc prolonging potential.