A systematic review of heart rate variability and menopausal vasomotor symptoms.

The menopausal transition is associated with increased cardiovascular disease (CVD) risk. Vasomotor symptoms (VMS) are highly prevalent during this period, potentially due to autonomic nervous system (ANS) changes. This systematic review examines whether heart rate variability (HRV), a noninvasive marker of autonomic function, differs between women with and without VMS. Five databases were searched. Studies were included if they assessed HRV in women with and without VMS while in peri- and/or post-menopause. Means, standard deviations, and sample sizes were extracted. Pooled standardized mean differences were calculated using a random-effects model with restricted maximum likelihood estimation. Heterogeneity was assessed using Cochrane's Q and I 2 statistics. Three studies were suitable for meta-analysis. The pooled analysis revealed no difference in low frequency (LF) in women with VMS compared to those without VMS (Difference in means: 2.715 [95% CI: -0.124 to 5.555]; p = 0.06). There were no group differences in high frequency (HF) (p = 0.11). High heterogeneity was observed in both LF (Q = 73.96, p < 0.001, I 2 = 97%) and HF (Q = 61.82, p < 0.001, I 2 = 97%). Women with VMS and without VMS did not show differences in HRV. Larger, standardized studies are needed to better understand the relationship between autonomic function, VMS, and CVD risk.