"Through the Looking Glass:" Women and Heart Disease

      The Framingham Study is one of the few long-term prospective studies of cardiovascular disease that has included both men and women.   Women participated from the very beginning because investigators recognized that cardiovascular disease occurred later in life and with lower frequency in females.   They wanted to understand why women enjoyed this relative protection.

      With follow-up of 5,209 original study participants (2,873 women and 2,336 men) researchers have documented information about the incidence of coronary heart disease in Framingham Heart Study women and risk factors unique to women.

  • In both men and women, coronary heart disease (CHD) has exceeded that of other cardiovascular events such as stroke or congestive heart failure.

  • While coronary events occurred twice as often in men, with advancing age the incidence of events in women approaches that seen in men.

  • CHD manifests itself differently in men and women.   In women, angina (chest pain) was the most common initial symptom, whereas in men, myocardial infarction (heart attack) was the most frequent first coronary event.

  • Women with angina fared better than men, due primarily to the fact that men with angina were found to have more underlying heart disease.   However, women with angina experienced five times the risk of future coronary events compared to women free of angina.

  • When heart attack was the first coronary event, nearly half were unrecognized in women, compared to only one-third undetected in men.   Both men and women with unrecognized heart attacks usually presented with no symptoms at the time of the attack or had symptoms so atypical that neither they nor their physician suspected a heart attack.   These unrecognized heart attacks were found through review of a routine ECG.

  • Coronary attacks were more often fatal in women than in men, although those women who suffered heart attacks and survived had the same prognosis as men.

      Risk Factors Unique to Women:

    • Menopause was associated with a significant rise in coronary events as well as a shift to more serious manifestations of the disease.

    • Traditional risk factors such as high cholesterol to HDL ratio and left ventricular hypertrophy (enlarged heart) tended to equalize the "female advantage" in terms of their rate of disease as compared to men.   Diabetes was a particularly potent risk factor in women; the disease was associated with greater risk of CHD in women than in men.

  • Both men and women who "weight cycled" (repeated episodes of weight loss and gain) were at increased risk of coronary morbidity and mortality.

  • While smoking cessation rates were similar in men and women, women who smoked heavily (two packs daily) were less likely to quit than men.

  • Although many studies have demonstrated that men who are more active tend to live longer, it has never been clear that the same is true for women.   Physical exercise was an important factor in the "heart health" of the Framingham women.   The most active women had the most protection against heart disease.