Is heart rate variability associated with frequency and intensity of vasomotor symptoms among healthy perimenopausal and postmenopausal women?

Abstract

Objective: Research has suggested that the autonomic nervous system (ANS) is involved in the experience of vasomotor symptoms (VMS) during menopause. We examined the relationship of VMS intensity and heart rate variability (HRV), a measure of ANS function.

Methods: Women (n = 282) were recruited from three American states for a clinical trial of yoga, exercise, and omega-3 fatty acid supplements for VMS. To be eligible, women had to report at least 14 VMS per week, with some being moderate to severe. Sitting electrocardiograms were recorded for 15 min using Holter monitors at both baseline and 12-week follow-up. Time and frequency domain HRV measures were calculated. Women completed daily diary measures of VMS frequency and intensity for 2 weeks at baseline and for 1 week at the follow-up assessment 12 weeks later. Multivariable linear regression was used to assess the relationship between VMS and baseline HRV measures and to compare change in HRV with change in VMS over the 12 weeks.

Results: Baseline HRV was not associated with either VMS frequency or intensity at baseline. Change in HRV was not associated with change in VMS frequency or intensity across the follow-up.

Interpretation: Heart rate variability (HRV) was not associated with basal VMS frequency or intensity in perimenopausal and postmenopausal women experiencing high levels of VMS. Autonomic function may be associated with the onset or presence of VMS, but not with the number or intensity of these symptoms.

Trial registration: ClinicalTrials.gov NCT01178892.

Keywords: Heart rate variability; Hot flashes; Parasympathetic nervous system; Vagal tone; Vasomotor symptoms.