Effect of Laboratory Stressor onArterial Compliance inYoung Women

ABSTRACT

Introduction: Coronary Heart Disease (CHD) is lower in women in comparison to male which is attributedto the effect of estrogen on vascular system. However, report on estrogen replacement therapy in menopausalwomen on blood pressure reactivity is inconsistent. The psychosocial stressors of daily life trigger elevatedsympathetic response which is an important independent cardiovascular risk factor. Therefore, the presentstudy intends to determine the effect of laboratory stressor on arterial compliance in young women duringdifferent phases of menstrual cycle.Methods: It is a cross-sectional, observational study conducted on 24 students of 18-22 years of age group.The participants attended two sessions in late follicular (days 12-15) and luteal phase (days 21-24). Theanthropometric parameters and detailed menstrual history were recorded. They were exposed to a 5-minMental Arithmetic Stress Test (MAST). Peripheral SBP, DBP, central SBP, DBP, Heart rate (HR), AugmentationIndex, and brachial ankle pulse wave velocity (baPWV) were recorded before and during the test. Paired ttest was performed to compare the means of the parameters and linear regression analysis was done toexamine the association between cardiovascular parameters and MAST score in both phases. ANCOVA wasdone to examine the difference in MAST response between follicular and luteal phases.Results: BMI and WHR of the subjects were mostly within normal limits with few exceptions. Heart rate wassignificantly decreased during MAST in follicular phase. However, baPWV was increased significantly duringMAST in both phases. There was an increasing trend in other parameters during MAST in both phasesexcepting pulse pressure. No association between cardiovascular parameters and MAST score was revealedby linear regression analysis. There was no significant difference in MAST score in both phases.Conclusions: An increasing trend of cardiovascular parameters during MAST was observed because ofelevated sympathetic activity. A decrease in HR was observed in certain participants during both phaseswhile performing MAST. This decline in peripheral vascular response may enhance the risk of majorcardiovascular events in future. This study therefore concludes that the effect of laboratory stressor in theform of Mental Arithmetic Stress Test (MAST) superimposed on the effect of ovarian hormones, decreasesarterial compliance as measured indirectly by baPWV.