Because lupus most often occurs in women of childbearing age, and flare-ups often occur during menstruation
, some researchers have sought to uncover the link between lupus and sex hormones, especially estrogen. While progress has been made, the connection between lupus and estrogen remains highly controversial
. It is known that people with lupus have elevated levels of estrogen metabolites
and low levels of testosterone
(Patavino T et al 2001). Women with lupus have shown reduced levels of progesterone
(Folomeev M et al 1992).
Certain forms of estrogen are associated with inflammation, degenerative diseases, and estrogen dominance in people with lupus
(Cutolo M et al 2004). Estradiol (the strongest form of estrogen) binds to receptors on T-cells and B-cells, increasing activation and survival of those cells, and predisposing women to prolonged attacks on their immune system (Grimaldi CM et al 2002).
Studies examining the role of estrogen in lupus have looked at HRT to see if the use of estrogen and progesterone contributes to lupus. In a study of 351 menopausal women with lupus, subjects were assigned to take either traditional HRT (consisting of conjugated equine estrogen at 0.625 milligrams per day [mg/day] and medroxyprogesterone at 5 mg/day for days 1 through 12 of each month) or a placebo. At the end of the study, the researchers found that the synthetic HRT increased the risk of mild to moderate flare-ups (but not the risk of serious flare-ups)
in menopausal women with lupus (Buyon JP et al 2005).
Women with lupus should discuss the risks and benefits of estrogen therapy with their physicians because, based on these findings, there appears to be a risk that estrogen may exacerbate disease
. In addition, extra caution is recommended because conventional HRT is associated with hypercoagulability (abnormally increased ability of blood to clot), which is already an issue in people with SLE who have antiphospholipid antibodies (Petri M 2001).