Physical exercise before age 40 reduces hypertension in postmenopausal women
Cardiologists estimate that up to 80% of women may experience hypertension after menopause. To prevent the problem, women should adopt a physical exercise routine by age 40, years before menopause begins. The advice comes from a study by researcher Angelina Zanesco at the Universidade Estadual Paulista (UNESP), who coordinates research about biological mechanisms responsible for the increase in blood pressure among women in this age group.
The first results of the study, which is supported by the Foundation for Research Support of São Paulo (FAPESP), were presented at the 28th Annual Meeting of the Federation of Societies for Experimental Biology (Fesbe), held August 21-24 in Caxambu, Minas Gerais, Brazil. “Many women begin to worry about physical activity only after age 50, when their bellies start to grow. But our results show that to prevent hypertension, women need to begin an exercise routine before the metabolic and hormonal changes of menopause,” said Zanesco.
To reach this conclusion, the staff of the Laboratory of Cardiovascular Physiology and Physical Activity UNESP Rio Claro(SP) evaluated in two groups of women - before and after menopause. They looked at the renin-angiotensin system, a hormone system that regulates blood pressure and water (fluid) balance.
“The renin-angiotensin is responsible for raising blood pressure, mainly through the constriction of blood vessels, and it has physiological importance. In the case of an accident with unusual bleeding or a generalized infection, for example, this system prevents the pressure from becoming too low. But when the mechanism is activated unnecessarily, it ultimately leads to hypertension," explained Zanesco.
“When we investigate only the normotensive(normal blood pressure) women, pre and post menopause, we do not see big differences. But, when comparing hypertensive women, the increased activity of the renin-angiotensin system reaches 150%. This data shows that if women expect menopause to change their lifestyle, it may be a little late and this system has already been activated to cause disease,” said Zanesco.
At the moment, researchers are trying to determine the mechanisms by which biological physical activity helps regulate blood pressure. The first hypothesis, which was not confirmed, is related to a reduction in the levels of cortisol and testosterone. Another hypothesis to be investigated is that physical activity stimulates the release of antioxidant enzymes such as superoxide dismutase(SOD) and catalase (CAT), which promote the reduction of oxidative stress and help reduce blood pressure.
According to data from the Brazilian Cardiology Society (SBC), hypertension is responsible for 40% of heart attacks, 80% of strokes and 25% of ESRD(end stage renal disease). Till age 55 there is a higher percentage of men with hypertension, according to the Brazilian Guidelines on Cardiovascular Disease Prevention. Among 55-74 year olds, the percentage of women is slightly higher. Over age 75, the prevalence of hypertension in females is significantly higher. The experts who formulated the guideline estimate that about 80 % of women eventually develop hypertension after menopause.