Heart rate variability [HRV] in young healthy females with primary dysmenorrhea

ABSTRACT

Primary dysmenorrhea affects more than 70% of young women. It may be associated with some degree of autonomic disturbances. Heart rate variability [HRV] is noninvasive technique to assess the cardiac autonomic balance. Low HRV reflects reduced parasympathetic [vagal] activity and/or elevated sympathetic tone and is considered an important cardiovascular risk factor. Was to investigate whether, in young healthy females with primary dysmenorrhea, alterations of cardiac autonomic function can be observed and, if so, whether these alternations affect their blood pressure and/or influenced by the body mass index BMI or the waist hip ratio WHR [visceral adiposity]. Twenty healthy young women participated in this study divided into two groups according to the results of The Menstrual Distress Questionnaire [MDQ]. Group 1 consisted of ten volunteers with primary dysmanorrhea. Group 2 [control] consisted often young females who where free from premenstrual symptoms. All subjects examined in the physiology laboratory, King Abdel Aziz University, 12 h post-prandial three times during a month-long screening period menses [day 1-5]; ovulation [day 11-21] and luteal [day 21-34]. Anthropometric measurements height, weight, body mass index [BMI], waist, hip circumference, and waist hip ratio [WHR], in addition to arterial blood pressure [ABP] were evaluated each time. The ANS activity was assessed by means of HRV. Time domain [heart rate [HR], RR interval[RR], the standard deviation of the normal RR-interval [SDNN], the root-mean square of differences of successive normal RR intervals [rMSSD], and power spectral analysis [high frequency [0.15-0.40 Hz] [HF]; low frequency [0.04-0.15Hz] [LF], and LF/HF ratio]] during supine resting condition. The two groups matched as regard age, and BMI. However, the group 1 had higher WHR compared to group 2. The ANS activity significantly changed [reduced vagus and increased sympathetic activities] in the luteal phase compared to the menses and follicular phases in Group L In addition, Group 1 possessed lower parasympathetic nerve activity [rMSDD and HF] throughout the cycle and higher sympathetic nerve activity in the late luteal phase compared to Group 2. The present study have demonstrated that although young females with primary dysmenorrhea had no significant changes in their HR and mean ABP comparing with matched group "as regards age and BMI" females with painless cycle, however, they had significant alteration in their cardiac autonomic activity in a form of decreased HRV with manifested fluctuation during the menstrual cycle