Testosterone-related shortening of QTc interval in women with polycystic ovary syndrome

Abstract

Context: The presence of several cardiovascular risk factors is observed in women with polycystic ovary syndrome (PCOS). On the other hand, the QTc interval duration, which is related to cardiac arrhythmia and sudden death, has not been investigated thoroughly in PCOS population. Objective: To investigate QTc interval duration and its relation to testosterone in women with PCOS. Design: Cross sectional case-control study. Setting: Outpatient setting, tertiary university medical centre. Patients: We enrolled 119 consecutive patients in whom PCOS was diagnosed based on oligomenorrhea, infertility (>2 yr), ineffective ovarian stimulation, and ultrasonographic criteria. The control group (controls) included 64 age-matched healthy women without clinical or laboratory evidence of PCOS. Interventions: In all participants we measured QTc interval duration on a standard electrocardiogram and determined plasma levels of high sensitivity C-reactive protein (hsCRP), endothelin-1 (ET-1), insulin, and testosterone. Main outcome measure: Shorter QTc interval duration in PCOS patients. Results: When compared to controls, PCOS patients displayed higher values of hsCRP (2.35±2.14 mg/l vs 1.18±1.24 mg/l; p=0.01), ET-1 (23.6±10.3 ng/l vs 12.9±20.7 ng/l; p=0.03), insulin (18.5±7.8 mIU/l vs 10.7±9.1 mIU/l; p=0.02), and testosterone (2.7±2.1 nmol/l vs 1.4±1.7 nmol/l; p=0.01). QTc interval in PCOS patients was significantly shorter than in controls (401±61 msec vs 467±61 msec; p=0.007), and inversely related to the plasma levels of testosterone (Spearman −0.45, p=0.005). Conclusions: QTc interval in PCOS patients is short, and inversely associated with increased levels of testosterone. QTc interval duration is not part of an adverse cardiac risk profile in PCOS.