Endometriosis and uterine fibroids may raise risk of early death in women

Women with a history of endometriosis and uterine fibroids might have an increased long term risk of premature death, finds a large study from the United States published by The BMJ today.

Endometriosis and uterine fibroids are common disorders among women of reproductive age. Endometriosis occurs when tissue similar to the lining of the womb grows in other places, such as the ovaries and fallopian tubes, while uterine fibroids are non-cancerous growths within or around the womb.

Growing evidence shows that both conditions are associated with a greater long term risk of chronic diseases, such as high blood pressure, heart disease, and some cancers, but their effect on risk of death before the age of 70 remains unclear.

To explore this further, researchers drew on information provided by 110,091 women taking part in the Nurses' Health Study II who were aged 25-42 years in 1989 and had no history of hysterectomy before endometriosis or fibroids diagnosis, cardiovascular diseases, or cancer.

Starting in 1993 and every two years thereafter, these women reported any diagnosis of endometriosis (confirmed by laparoscopy) and uterine fibroids (confirmed by ultrasound or hysterectomy).

Other potentially influential factors including age, ethnicity, reproductive history, HRT and oral contraceptive use, regular use of aspirin or anti-inflammatory drugs, and other health-related issues were also taken into account.

During 30 years of monitoring, 4,356 premature deaths were recorded, including 1,459 from cancer, 304 from cardiovascular diseases, and 90 from respiratory diseases. 

Overall, the rate of all-cause premature death for women with and without confirmed endometriosis was 2 and 1.4 per 1,000 person years, respectively.

After taking account of age and other confounding factors such as weight (BMI), diet quality, physical activity, and smoking status, endometriosis was associated with a 31% higher risk of premature death, largely driven by deaths due to gynaecological cancers.

Uterine fibroids were unrelated to all-cause premature death, but were associated with a greater risk of death due to gynaecological cancers.

The researchers acknowledge that these are observational findings that relied on self-reports, which can be prone to error, and included predominantly white healthcare workers, so results may not apply to other groups. Nor can they rule out the possibility that other unmeasured factors may have had an influence.

Nevertheless, this was a large study with regular follow-up over nearly three decades, which reduced potential recall errors.

As such, they conclude: "Our results suggest that women with a history of endometriosis and uterine fibroids might have an increased long term risk of premature mortality extending beyond their reproductive lifespan." 

These conditions were also associated with an increased risk of death due to gynaecological cancers. Endometriosis was also associated with a greater risk of non-cancer mortality. These findings highlight the importance for primary care providers to consider these gynaecological disorders in their assessment of women's health."