Hypertension (high blood pressure) remains one of the strongest predictors for major cardiovascular events, such as heart attack and stroke. Recent research finds the prevalence of hypertension is increasing among young women, and a new study published in the American Journal of Epidemiology considers premenstrual syndrome (PMS) as a possible risk factor.

Researchers explained "several mechanisms underlying hypertension might also contribute to PMS," such as renin-angiotensin aldosterone system dysfunction — a system responsible for sodium balance, blood volume, and arterial constriction, as well as hallmark PMS symptoms such as bloating and breast tenderness. But "whether women with PMS have a higher risk of subsequently developing hypertension has not been assessed," researchers said. To their knowledge, this is the first any study has set out to better understand this potential relationship.

Researchers analyzed data collected from 116,686 women in the U.S. who had participated in the Nurses' Health Study II (NHS2). Women were aged 25-42, provided their medical histories and health-related behaviors, like smoking and oral contraceptive use (also risk factors for hypternsion). Women also answered questionnaires every two years following the start of the study to update information on risk factors and report any new diagnoses. These questionnaires assessed the occurrence of PMS symptoms, too, and the impact they had on daily functioning.

Additionally, on each NHS2 questionnaire, women were asked whether they had received a clinician-made diagnosis of high blood pressure in previous years, and if clinicians had done this, when they received the diagnosis. Women reported their systolic and diastolic blood pressure periodically through the course of the study as well.

The results showed women with moderate-to-severe PMS had a 40 percent higher risk of developing high blood pressure over the following 20 years compared to women who experienced few menstrual symptoms. This risk persisted after researchers adjusted for women's age, body mass index, cigarette smoking, physical activity, alcohol consumption, oral contraceptive use, and a family history of hypertension. And this risk was even higher for women under the age of 40 — young women faced a three-fold higher risk of developing hypertension compared with women without PMS.

Researchers explained "an association between PMS and hypertension could be explained alternatively by adverse effects of PMS medications on blood pressure," namely antidepressants. Prior studies have shown popular antidepressants, called serotonin-norepinephrine reuptake inhibitors, increase blood pressure, while selective serotonin reuptake inhibitors have generally not been associated with hypertensive disorders. In the present study, researchers found women with PMS who used antidepressants did not have higher risk of hypertension.

More research needs to be done to confirm this observation, but if the idea stands, researchers suggest diet may be a way to lower risks of developing PMS. They observed women with higher dietary intakes of B vitamin thiamine and riboflavin were 25 to 35 percent less likely to experience PMS. And in another study, sourcing riboflavin, thiamine, and folacin (folic acid) from food was inversely associated with blood pressure.

Source: Bertone-Johnson E, at al. Premenstrual Syndrome and Subsequent Risk of Hypertension in a Prospective Study. American Journal of Epidemiology. 2015.