Hot Flashes Are Associated With Ambulatory Systolic Hypertension

March 27, 2007 — In women with normotension or mild hypertension and who experience hot flashes, awake and sleep systolic blood pressure (BP) is significantly high, independent of menopausal status, according to the results of a study reported in the March/April issue of Menopause.

"Menopause is associated with a rise in BP in many, but not all, studies," write Linda M. Gerber, PhD, from the Weill Medical College of Cornell University in New York, and colleagues. "One of the most important features of menopause is hot flashes, which are thought to be caused by centrally increased activation of the sympathetic nervous system, but there is a surprising lack of information as to whether this affects BP. During a hot flash there is an increase in peripheral blood flow, finger temperature, and plasma epinephrine, which may be accompanied by an acute fall in BP."

As part of a cross-sectional study on ethnicity, socioeconomic status, and diurnal BP patterns, the investigators evaluated 154 women (mean age, 46 years; range, 18 - 65 years) who were either normotensive or mildly hypertensive. Study participants wore an ambulatory BP monitor for 24 hours, recorded their awake and sleep times, and completed an everyday complaint questionnaire that embeds symptoms associated with menopause into a list of everyday complaints.

During the 2 weeks before they completed the questionnaire, 33% of participants reported having had hot flashes. Compared with women who did not report hot flashes, those who reported having had hot flashes had significantly higher mean awake and sleep systolic BP values (P < .004 and P = .007, respectively). After controlling for age, race/ethnicity, body mass index, and menopausal status, hot flashes continued to independently predict average awake and sleep systolic BP (P = .03 for both). Hot flashes were not associated with diastolic BP or with nocturnal decreases in BP.

Study limitations include the sample not being representative of women at all levels of BP nor of those with coronary artery disease.

"Hot flashes are associated with increased awake and sleep systolic BP independent of menopausal status," the authors write. "Future researchers should seek to determine whether this relationship is causal or is related to one or more shared etiological factors, such as elevated sympathetic activity. If the relationship is found to be causal, then further elucidation of the mechanisms underlying this relationship may help to identify potential interventions that would reduce the impact of hot flashes on BP."

The National Heart, Lung, and Blood Institute and Weill Medical Center General Clinical Research Center supported this study. The authors have disclosed no relevant financial relationships.

Menopause. 2007;14:308-315.

Source: http://www.medscape.com/viewarticle/554149?src=mp