NEWS: Joint pain and estrogen deprivation

[Guest guest]

Public release date: 2-Sep-2005

Wiley & Sons, Inc.

Joint pain and estrogen deprivation

Recent evidence suggests caution in prescribing hormone therapy for

breast cancer and sheds new light on “menopausal arthritis”

One of the most effective new treatments for breast cancer is a

hormone therapy. Aromatase inhibitors work by powerfully blocking the

conversion of androgen precursors into estrogens, which lowers

estradiol levels in the bloodstream and estrogen levels in peripheral

tissues. Because aromatase inhibitors reduce the rates of recurrence

in women with early-stage postmenopausal breast cancer, these agents

are not only becoming widely used in breast cancer treatment, but

also being explored for their potential to prevent the disease in

women at high risk. While focusing on this therapy's promise,

advocates have tended to downplay one of its drawbacks. Women treated

with aromatase inhibitors often experience joint pain and

musculoskeletal aching--severe enough, in some cases, to make them

stop the treatment.

Two noted researchers, T. Felson, M.D., of Boston University

Clinical Epidemiology Unit, and R. Cummings, M.D., of

California Pacific Medical Center Research Institute and University

of California, San Francisco, have thoroughly examined the evidence

linking aromatase inhibitors and, more broadly, estrogen deprivation

joint pain. In the September 2005 issue of Arthritis & Rheumatism

(http://www.interscience.wiley.com/journal/arthritis), they share

their insights to alert oncologists, primary care physicians, and

other health care professionals to this widely overlooked, potential

problem for women.

" Estrogen's effects on inflammation within the joint are not well

known, " Dr. Felson and Dr. Cummings observe. Yet, as they note,

estrogen has well-established tissue-specific effects on inflammatory

cytokines. Estrogen's role in joint inflammation could account for

the increased sensitivity to pain that some women suffer with

estrogen depletion. Citing studies of pharmacological suppression of

estrogen and studies of natural menopause, the authors offer a look

at compelling evidence associating estrogen deprivation with joint

pain, including:

Aromatase inhibitors have been linked to higher rates of joint and

muscle pain than tamoxifen and placebo in various clinical trials for

breast cancer treatment and prevention. One example: In a National

Cancer Institute of Canada study, 5,187 postmenopausal women who

completed a 5-year course of tamoxifen therapy for breast cancer were

randomized to a further 5 years receiving the aromatase inhibitor

letrozole or a placebo. 21 percent of women taking letrozole reported

joint pain compared with 16 percent of the women receiving placebo.

In a study of leuprolide, a hormonal agent used to treat infertility

and a variety of gynecological disorders, 102 premenopausal women

experienced symptoms of estrogen deprivation, such as vaginal

dryness, after 2 weeks of treatment, and suffered joint pain between

weeks 3 and 7 of treatment. Overall, 25 percent of the women

developed persistent joint pain, affecting the knees, elbows, ankles,

and other areas, during the study. The pain was resolved in all women

between 2 and 12 weeks after stopping the leuprolide therapy.

In a postmenopausal estrogen/progestin intervention trial, women who

received estrogen had a significantly decrease chance of

musculoskeletal symptoms--between 32 and 38 percent--compared with

women randomly assigned placebo. Symptoms reported in the placebo

group included joint pain, muscle stiffness, and skull and neck

aching. In other studies, however, estrogen replacement therapy had

no beneficial effect on musculoskeletal pain.

Dr. Felson and Dr. Cummings also highlight recent data showing that

Asian women undergoing menopause have lower estradiol levels than

Caucasian women and seem to be more vulnerable to a syndrome commonly

known as " menopausal arthritis. " They also note the high rate of both

osteoarthritis and rheumatoid arthritis in postmenopausal women. They

conclude by stressing the need for further research into the

contribution of estrogen deficiency to arthritis, as well as for

recognizing the risks of musculoskeletal syndrome when prescribing

aromatase inhibitors and other estrogen-depleting treatments.

http://www.eurekalert.org/pub_releases/2005-09/jws-jpa082605.php