Early, Late Menarche Raises CV Risk in Senior Women: UK Study

Marlene Busko

December 15, 2014

OXFORD, UK — Women in their 60s and 70s who had their first menstrual period when they were much younger or older than the average age of 13 have an independently elevated risk of cardiovascular events, suggests an analysis based on the UK Million Women Study[1].

The study, published online December 15, 2014 in Circulation, found that there was a U-shaped association between age of menstrual onset and subsequent death or hospitalization from CAD, stroke, or complications of hypertension in middle age. The relationship was consistent among women from all socioeconomic groups, whether they were lean, overweight, or obese or current or past smokers or nonsmokers. 

"Our findings suggest that women's reproductive health may influence [their] long-term vascular health, which may become apparent when they reach middle age," lead author Dr Dexter Canoy (University of Oxford, UK) told heartwire in an email. This study is the first that is large enough to reliably quantify the vascular outcomes in midlife that are associated with early (and late) puberty in women, but the mechanism remains unknown, he noted.

Moreover, "the impact [from very early or late puberty], of course, is not as great as from other well-established risk factors . . . [which] should remain the focus of preventive efforts, [since] there is a lot to gain from addressing hypertension, high blood cholesterol, and smoking as well as weight control (through appropriate lifestyle changes or pharmacotherapy), as shown from other studies," Canoy cautioned.

Nevertheless, this study draws attention to the fact that childhood obesity, which is linked with early puberty, is increasing, and the age of a woman's first menstrual period is getting lower. Thus, "it is possible that in the future, more women will develop heart disease as a result of having had early menarche," Canoy said. Public-health strategies aimed at tackling childhood obesity could potentially reduce this trend of a lower average age of a woman's first menstrual cycle, which may in turn reduce the risk of developing heart disease.

Million Women Study and CAD, Stroke Risk

Some generally small studies have suggested that women who enter puberty at a younger age have an increased risk of CAD or stroke, but the results have been inconsistent, Canoy and colleagues explain. Data from the Million Women Study provided the researchers with an opportunity to investigate this association in a large population.

The  population-based cohort study recruited 1.3 million women aged 50 to 64 years who had been invited for routine breast-cancer screening by the National Health Service program in England and Scotland between 1996 and 2001.

About 70% of women who attended the screening program—representing one in four women in the UK in the target age group, the group writes—agreed to reply to a questionnaire about determinants of health.

The women had a mean age of 56, and, on average, they reported that they had their first menstrual period at 13; however, 3.9% were 10 or younger and 1.4% were 17 or older when they had their first menstrual period.

The current study looked at 1.22 million participants who were followed for a mean of 11.6 years. During this time, 73 378 women had incident CAD (68 744 hospitalizations and 4634 deaths), 25 362 women had incident stroke, and 249 426 women had incident complications of hypertensive disease.

Women who were older or younger than 13 when they had their first menstrual period were at increased risk of having these vascular outcomes, after adjustment for birth year, body-mass index, height, smoking, alcohol consumption, exercise, and socioeconomic status.

During the 11.6–year follow-up, compared with women who entered puberty at age 13, those who entered puberty at 10 or younger had a 27% higher risk of being hospitalized for or dying from CAD (95% CI 22%­–31%). Those who entered puberty at 17 years or older had a 23% increased risk of this outcome (95% CI 16%–30%).

Similarly, compared with women who entered puberty at age 13, entering puberty at 10 or younger or 17 or older was associated with a significant excess risk of stroke of 16% (95% CI 9%–24%) and 13% (95% CI 3%–24%), respectively.

Women also had an up to 20% increased risk of being hospitalized for or dying from complications of hypertension if they had especially early or late onset of puberty.

"Whether the occurrence of early menarche per se ( . . . due to obesity or other factors) or some [other] factor somehow alters the vascular milieu, which would subsequently increase susceptibility to the impact of other environmental/lifestyle factors on heart disease over the life course of such women," remains unknown, Canoy noted. The mechanism for the increased risk for vascular disease associated with late onset of puberty is also unknown.

The researchers plan to explore these associations further, including in other populations that have very different distributions of the mean age of puberty.

"In the meantime, several clinical implications can be derived: We need to learn that female-specific risk indicators may be a valuable source of refining a woman's individual cardiovascular disease risk assessment," writes Dr Renate B Schnabel (University Heart Center, Hamburg, Germany) in an accompanying editorial[2].

"For a general cardiologist, a seemingly distant event such as puberty and age at menarche may provide valuable information. Besides pregnancy-associated complications and menopausal characteristics, pubertal development and menarche may become a routine part of taking a female's medical history, not only for the general practitioner but also for the cardiologist."

The research was supported by Cancer Research UK, the Medical Research Council, and the National Health Service Cancer Screening Programme. The authors and editorialist have reported they have no relevant financial relationships.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: