Analysis of heart rate variability in polycystic ovary syndrome

Abstract

Objective. To compare the modulation of heart rate in a group of volunteers with polycystic ovary syndrome (PCOS) to that of a group of healthy ovulatory women on the basis of R-R interval variability and analyze the relationships between heart rate variability (HRV) and other cardiovascular risk factors.

Methods. In a cross-sectional study, HRV and anthropometric, biochemical and hormonal parameters were measured in 23 women with PCOS and 23 age-matched controls. Mean outcomes measures: HRV indexes in the time (SDNN and rMSSD) and frequency domain (low frequency–LF and high frequency–HF). Differences between groups and correlation analysis were performed.

Results. Intergroup analysis showed significant differences (p < 0.05) between groups, with lower SDNN, rMSSD, LF and HF indexes in PCOS women when compared to the control group. There was significant negative correlation between BMI and SDNN, LF and HF, indicating a decrease in the autonomic modulation of heart rate with increasing weight. A negative correlation was also found between the high-sensitivity C-reactive protein level and the rMSSD index.

Conclusion. Our results show that PCOS is associated with alterations in the autonomic modulation of heart rate, possibly due to the influence of weight gain.

Keywords:

• Polycystic ovary syndrome
• insulin resistance
• body mass index

Acknowledgements

This work was financial supported in part by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ), Ministério da Saúde do Brasil, Secretaria Estadual de Saúde Pública do Estado do Rio Grande do Norte and Fundação de Apoio à Pesquisa do Estado do Rio Grande do Norte (FAPERN). We thank Técia Maria Maranhão, Elvira Mafaldo Soares and resident doctors for the participation in the clinical evaluation of volunteers.