"Middle-aged women who are considering hysterectomy should be encouraged because our results suggest that increased levels of cardiovascular risk factors are not any more likely after hysterectomy relative to after natural menopause," said Karen A. Matthews, PhD, lead author of the study and a distinguished professor of psychiatry and professor of epidemiology and psychology at the University of Pittsburgh.
Hysterectomy is the surgical removal of a woman's uterus; it is sometimes accompanied by the removal of the ovaries to decrease the risk of ovarian cancer. Hysterectomy is a common surgical procedure for women, but the benefits must be weighed against potential long-term related health consequences. Cardiovascular disease is the number one killer of women and many studies have shown increased risk of cardiovascular disease to be a health risk associated with hysterectomy, especially accompanied by ovary removal. Researchers in those studies usually evaluated cardiovascular disease risk factors years after hysterectomy and/or ovary removal and did not assess individual risk factor levels pre-surgery.
For this study, investigators followed 3,302 premenopausal women between the ages of 42-52 for 11 years who were enrolled in the Study of Women's Health across the Nation (SWAN). Researchers compared cardiovascular disease risk factors in women prior to and following elective hysterectomy with or without ovary removal to the risk factors prior to and following final menstrual period in women who underwent natural menopause.
This is the only multiethnic study that has tracked prospective annual changes in cardiovascular disease risk factors relative to hysterectomy or natural menopause.
Investigators found that several cardiovascular disease risk factor changes differed prior to and following hysterectomy, compared to changes prior to and following a natural menopause, but those changes did not suggest an increased cardiovascular disease risk following hysterectomy, independent of body mass index, which did increase after hysterectomy with removal of ovaries. These effects were similar in all ethnic groups in the study.
Dr. Matthews said it is unclear why this study's findings differed from other studies exploring hysterectomy and cardiovascular risk, but likely factors include the age of participants since hysterectomy that occurs earlier in life may present more cardiovascular risk. Also, earlier studies included women who had hysterectomy for any reason, whereas the SWAN study excluded women who had hysterectomy because of cancers.
"This study will prove very reassuring to women who have undergone hysterectomy," said American College of Cardiology CardioSmart Chief Medical Expert JoAnne Foody, MD, FACC. "As with anything, if a woman is concerned about her risk for heart disease she should discuss this with her health care provider."