Hormones and Your Mind

[Guest guest]

Hormones and Your Mind

L. Klaiber, MD

UMass Memorial Medical Center

o you ever feel so irritable, anxious or

muddle-headed that you wonder if you're losing your mind? Blame it on

hormones.

Encouraging:

Hormone therapy (HT) often can prevent or correct much of the moodiness

and mental decline associated with menopause. Such improvements usually

occur after just a month or so of HT. Some women improve dramatically.

Discouraging: Most women who could benefit

from HT are not getting it -- because most doctors are wary about

prescribing it.

The Big Four

Of the body's many hormones, four particularly affect brain function

at midlife...

Estrogen

helps to maintain the strength and structural integrity of our brain

cells and protects against damage to them. When estrogen levels are

low, the brain actually can atrophy. Low levels of estrogen can lead to

memory loss and mood swings, and may even contribute to Alzheimer's

disease.

In

addition, estrogen regulates blood flow to many parts of the brain that

affect cognitive function. Brain nerve cells communicate with one

another by secreting chemical neurotransmitters that influence

reasoning, emotions and other brain functions.

Certain brain

cells have dendrites -- delicate twig-like structures with tiny spines

that pick up messages carried by neurotransmitters. These spines depend

on estrogen and testosterone to remain healthy. As women age and these

hormones decline, some of these spines are lost -- so communication

between brain cells is impaired. Women may begin to feel anxious and

find it hard to sleep or to concentrate. Estrogen therapy can help to

maintain the health of these spines.

Estrogen also may improve the effectiveness of antidepressant

medications. Studies show that some selective serotonin reuptake

inhibitors, such as fluoxetine

(Prozac), may work more quickly, more effectively and/or for a greater

percentage of postmenopausal women when estrogen therapy also is used.

Testosterone

is often thought of as a male hormone, but women produce it, too.

Testosterone influences areas of the brain that regulate learning and

memory, as well as sexual responsiveness. As testosterone levels

decline gradually with age, a woman may have more trouble

concentrating. Low testosterone also causes the sexual center in the

female brain to shrink, resulting in lowered desire.

Women's

testosterone levels are naturally lower than men's. Fortunately, even

these low levels now can be measured accurately with blood tests. For

some women, low-dose testosterone therapy provides increased energy,

improved mood and a reinvigorated libido.

Progesterone

regulates menstruation, prepares the body for pregnancy and modulates

the effects of estrogen, which in excess amounts can cause cancer.

Progesterone also affects the brain. But whereas estrogen and

testosterone have an antidepressant action, progesterone can have a

depressant effect -- causing mood swings and irritability in some

women. Progesterone also has a negative effect on sex drive. The

highest progesterone levels occur prior to each monthly menstrual

period and are related to symptoms of PMS. Levels of progesterone

decline gradually during perimenopause (the years during which the body

transitions into menopause) and become quite low after menopause.

Thyroid hormone

regulates metabolism for the whole body. In the brain, it appears to

aid the activity of neurotransmitters. A midlife drop in thyroid

hormone levels is thought to be related to the drop in estrogen at

menopause. More than 10% of women over age 55 develop mild

hypothyroidism (low thyroid hormone levels), which can cause mood

swings and/or depression. This can be treated with thyroid hormone

therapy.

HT Fears Calmed

Until

five years ago, HT was the standard treatment for menopausal symptoms,

including moodiness, memory problems, hot flashes and vaginal dryness.

It also appeared to protect against heart disease and osteoporosis

(brittle bones). But in July 2002, the Women's Health Initiative (WHI)

-- a large clinical trial sponsored by the National Institutes of

Health -- reported that estrogen therapy increased the risk for heart

attack, stroke, blood clots and breast cancer, so doctors stopped

prescribing it. What we know now that we didn't know then...

Participants' average age was 63 -- much older

than most women for whom

HT is recommended today. Older WHI participants were already at

increased risk for heart attack and stroke before they entered the

study. Here's why: Estrogen protects against arterial

disease, as shown by a recent study in The New England Journal of

Medicine.

Most WHI subjects had not been on estrogen therapy prior to the study

and therefore were prone to develop arterial disease. When women with

diseased arteries are given estrogen, the hormone may trigger blood

clots that can lead to heart attack and stroke.

WHI subjects who had not had a hysterectomy were

given daily estrogen

and progestin (a synthesized pharmaceutical with effects similar to

progesterone). This combination is now known to increase the incidence

of heart attack, stroke and breast cancer.

New:

A reevaluation of WHI data shows that for women under age 60 who are

less than 10 years past menopause, estrogen therapy generally is safe

and protects against heart disease. It is sometimes appropriate for

women in their 60s who have no signs of heart disease.

Important:

Women who have not had a hysterectomy and who take estrogen also should

take progesterone to protect against uterine cancer. But since daily

progesterone may increase the risk for breast cancer and heart attack,

many doctors now advise taking it for only about 10 days per month.

To

find an endocrinologist or gynecologist who is up to date on the

safest, most effective ways to use HT, contact the nearest medical

center associated with a medical school. Best results come from an HT

regimen that is tailored to a woman's individual needs.

Bottom Line/Women's Health

interviewed L. Klaiber, MD, a leading researcher and clinician

in the field of psycho-neuro-endocrinology. He is consultant

endocrinologist at UMass Memorial Medical Center, Worcester,

Massachusetts. Dr. Klaiber is the author of Hormones and the Mind: A Woman's Guide to

Enhancing Mood, Memory, and Sexual Vitality (Harper).