Sexual dysfunction in women can be linked to low resting heart rate variability, a finding that could help clinicians treat the condition, according to a study by psychologists from The University of Texas at Austin.
Heart rate variability (HRV) -- the variation in the time intervals between a person's consecutive heartbeats -- can indicate how well an individual responds to physiological and environmental changes. Low resting heart rate variability has been associated with several mental health conditions, such as depression, anxiety and alcohol dependence, as well as erectile dysfunction in men.
"Because HRV has been related to many negative mental health and cardiac problems, it's interesting to bring an established clinical marker into sex research," said Amelia Stanton, a UT Austin graduate researcher and lead author of the study. "It allows us to look at the issue of sexual dysfunction in women in a different way."
HRV is a sensitive and objective measure of the autonomic nervous system, which comprises the sympathetic nervous system -- the body's flight or fight response -- and the parasympathetic nervous system -- the body's involuntary actions, such as breathing and heartbeat. When the body is stable, the parasympathetic nervous system should have greater effect on heart rate.
However, moderate sympathetic nervous system activation has been shown to increase women's genital arousal, Stanton said.
Using the Female Sexual Function Index, which considers domains such as pain, satisfaction and desire, researchers analyzed HRV and self-reported data from 72 women aged 18-39 to evaluate overall sexual functioning.
"The Female Sexual Function Index has been shown to effectively identify women with clinically significant levels of sexual dysfunction," said co-author and UT Austin psychologist Cindy Meston, who co-authored a study to develop the index in 2000.
Researchers found that in addition to overall sexual dysfunction, women with below average HRV were more likely to experience difficulties with sexual arousal.
With recent support from the Food and Drug Administration on what could be the first-ever approved drug for the treatment of female sexual dysfunction, the researchers believe that HRV could be used as an index of drug-related changes in sexual function.
"Because evidence shows that low HRV is a potential risk factor for sexual dysfunction, physicians have a simple, low-cost and nonintrusive method to measure a woman's risk for sexual dysfunction," said Stanton. "It makes it easier to talk about something a little bit more private and get women the help that they need."
"Heart Rate Variability: A Risk Factor for Female Sexual Dysfunction," co-authored by Tierney Lorenz from the Kinsey Institute for Sex, Gender and Reproduction at Indiana University and Carey Pulverman, a UT Austin psychology researcher. Published online in the journal Applied Psychophysiology and Biofeedback on June 17, 2015.