Life
expectancy for women in the United States is 80.1 years; for men, it
is 74.8 years.1 As a result, most women will spend more than one-third
of their
lives in a postmenopausal state and face many health problems associated with
reduced levels of endogenous estrogen,2 progesterone, DHEA, and testosterone.
Men face similar challenges. Bio-identical hormone replacement therapy (BHRT)
can be a safe and effective means to assist women and men at this stage in their
lives.
The safety of hormone replacement therapy has been a hot topic of discussion,
especially since the 2002 publication of the results of the Women's Health
Initiative (WHI). In the WHI, women were using non-bio-identical hormone replacement
therapy. Fortunately, the safety of BHRT has been well-researched. BHRT has fewer
side effects, especially if used in a cream or gel and applied over the skin
or mucous membranes. Some examples of BHRT's benefits include the following:
- a decrease in cardiovascular risk is shown in multiple
studies when estrogen is used transdermal rather than oral,3
- endometrial
hyperplasia is less in low-potency transvaginal estriol or estradiol
than with oral estrogen,4
- the metabolism of estradiol, when used
transdermally, has less tendency towards estrogen related cancers
due to its end product ratios,5 and
- if used appropriately, the combination
of percutaneous progesterone with percutaneous estradiol can decrease
the estradiol-induced proliferation
of cyclical epithelial breast tissue; this was shown in vivo prior to breast
surgery
if applied
to normal breast tissue.6
Finally, in another review,
the conclusion was made that sex hormones are not oncogenic, but mitogenic.7
BHRT research is mostly lacking two aspects. First, the research is not long-term,
and second, few studies are done at the cellular level. We do not know to
what extent the mitogenic activity of bio-identical hormones is affecting us
at
a cellular level, especially if used long-term. To help allay concerns about
the
safe use of BHRT, we can use careful follow-up testing to monitor not only
levels of the steroid hormones, but also their metabolites, relevant enzymes,
and hormone
ratios.
The most comprehensive and accurate testing method is the 24-hour urine test.
Since serum steroid hormone levels naturally fluctuate, sometimes considerably,
due to varying half-lives, pulsatile secretion, and (in the case of exogenously
applied hormones) time of application, the 24-hour urine collection "averages
it all out."
Urine testing is performed with gas chromatography (GC). GC is still unsurpassed
in its potential for determining a multitude of steroid metabolites simultaneously
in a single steroid profile. Used together with a mass spectrometer (MS)
as a detector, this technique ensures the highest specificity in determining
steroid
metabolites.8,9 Urine testing measures the sum of free and conjugated (sulfated
and glucuronidated) hormonal steroids, not the inactive, protein-bound hormones.
According to the 1999 edition of Tietz' Textbook
of Clinical Chemistry, "Urinary
assays are considered to reflect the secretory activity of the endocrine glands."10
The textbook also states that "urinary free cortisol and the measurement
of urinary free estradiol, estrone, and testosterone have been shown to provide
clinical information that can reflect the production rates of these steroids."10
Moreover, 24-hour urine testing for pregnanediol (progesterone metabolite) is
the best biochemical assessment of ovulation based on progesterone production.
The most satisfactory alternative is plasma, and the least satisfactory is saliva.11
Lastly, estriol can be more accurately measured in the urine (where estriol is
routinely found to be higher than estradiol or estrone). Circulating serum levels
of estriol are often found to be quite low, due to its rapid clearance from the
body.12
Serum testing is a direct assessment of circulating hormones. Moreover, serum
levels have well-established reference ranges. Unfortunately, bio-available
and non-protein-bound forms are rarely measured, with the exception of testosterone.
Also, serum is only a one-time measurement within a 24-hour period. To be
more accurate, two or more blood draws can be taken within a 24-hour period.
To
evaluate
hormone levels via serum, different laboratories use various immunoassays.
However, lack of comparability exists with the different immunoassays. Some
immunoassays
even lack specificity and can have detrimental effects on medical practice.
For example, microparticle enzyme immunoassay has errors in estradiol measurements
due to interference from unconjugated estriol.13
Saliva testing measures the free, or active, form of steroid hormones via
the radioimmunoassay technique. It is a convenient and non-invasive testing
method.
For example, monthly fluctuations in hormone levels are easily monitored
so that follicular, ovulatory, and luteal phases can be determined. Moreover,
four separate
measurements in one day can help determine the cortisol circadian rhythm.
Dr. John Lee was a strong advocate of salivary hormone testing, particularly
for monitoring transdermal progesterone. He wrote that transdermal progesterone
is highly lipophilic, absorbed through the skin into the fat layer, taken
up gradually by red blood cell membranes, and made readily available to all
target
tissues and saliva.14 However, this may not be completely accurate, as the
serum content of progesterone has been shown to be higher than the red blood
cell membrane
content. In one study, after transdermal application, plasma progesterone
and pregnanediol-3-glucuronide (progesterone metabolite) excretion showed
small
increases, red cell progesterone never exceeded plasma levels, and salivary
levels were
very high and variable compared to placebo.15 This study also indicates the
possibility of false representation of overdose with salivary testing after
the use of progesterone
cream. Another small study on saliva testing, published in 2003, found variation
in results within each laboratory for each participant. The researchers concluded
that at-home saliva testing was not reliable.16 However, this needs to be
repeated with a larger sample size.
Saliva is a difficult matrix to deal with experimentally.17 The presence
of both sex hormone-binding globulin and corticosteroid-binding globulin
in uncontaminated
saliva casts doubt on the reliability of salivary steroids to accurately
reflect circulating free steroid levels.18 Lastly, caution should be exercised
in androgen
assays, as well as in assays to assess ovarian function. The use of salivary
cortisol for measuring endogenous cortisol is the most encouraging.19
As mentioned above, 24-hour urine testing for steroid hormones is extremely
valuable, due to the many metabolites that are measured. This is especially
true for estrogen
and adrenal hormone metabolites. There are more than 20 circulating estrogens
in the body; however, estrone, estradiol, and estriol are generally cited
as the main players. Estrone and estradiol are potent estrogens, whereas
estriol
is a relatively weak estrogen. All these values are measured in urine steroid
hormone testing, whereas serum testing usually incorporates only estradiol,
although estrone can be ordered as well. Urine testing provides free and
conjugated values
for estrone, estradiol, and estriol, as well as many downstream metabolites
for each of these hormones, while serum testing incorporates protein-bound
estradiol
only.
To further complicate matters, each of these hormone metabolites has actions
of its own. Some estrone is metabolized to 4 OH estrone, which may encourage
the growth of breast or prostate cancer.20 Yet another metabolite of estrone,
16 alpha OH estrone, is considered an "unsafe" estrogen metabolite,
as it is a potent estrogen with uterotopic effects similar to estradiol. This
estrogen metabolite forms covalent bonds with amino groups of macromolecules
and is genotoxic.21 Estrone is also metabolized to 2 OH estrone, a relatively
weak metabolite that may be anti-estrogenic.22 Other metabolites, 2-hydroxyestrone
and 2-hydroxyestradiol, offer protection against the estrogen-agonist effects
of 16-alpha-hydroxyestrone.23,24 However, 16 alpha OH estrone appears to play
an important role in maintaining bone density. As this very brief discussion
of estrogen metabolites demonstrates, monitoring how patients metabolize their
hormones and what factors may modify hormone metabolization is important. Many
patients are taking diindolylmethane (DIM) or indole 3 carbinol (I3C) for "safe" estrogen
metabolism. These substances improve the "2/16" ratio, which is known
to decrease the risk of breast cancer.25 But not all patients need DIM or I3C,
as they may already have a healthy 2/16 ratio, and using these substances may
overly decrease the 16 alpha hydroxyestrone fraction, increasing risk for osteoporosis.26
Adrenal hormone values and their metabolites, which are measured in the 24-hour
urine test, may point toward significant adrenal dysfunction. Here are some
examples:
- Elevated levels of pregnanetriol indicate congenital adrenal
hyperplasia. This is a disorder most often caused by a 21-hydroxlase
deficiency and can lead
to cortisol and aldosterone deficiencies, as well as progesterone and
androgen excess.
- The cortisol/cortisone should be ~0.7/1. Elevated
cortisol/cortisone ratios can be a sign of "Apparent Mineralocorticoid
Excess." Elevated
ratios are also indicative of licorice excess. Hypertension can occur
in either case, as cortisol has an aldosterone-like activity and
cortisone does not.
- The cortisol metabolites tetrahydrocortisone,
tetrahydrocortisol, and
allo-tetrahydrocortisol account for approximately 50% of daily
cortisol biosynthesis.27 If these metabolites add up to 5 mg, then
the body is producing
about 10 mg of
cortisol daily. This is useful in determining adrenal excess or
deficiency. In an unpublished study by Patrick N. Friel, BS, at Meridian
Valley Labs, all
patients
who failed the 250mcg ACTH (2/10) stimulation test had low cortisol
metabolites in the baseline 24-hour urine.
- 11-dehydrotetrahydrocorticosterone
is an inactive metabolite of corticosterone. Compared to cortisol,
corticosterone has approximately one-third
the anti-inflammatory action but 15 times the sodium-retaining action.
- Allo-Tetrahydrocorticosterone
and tetrahydrocorticosterone are sensitive markers for monitoring
adrenal stress. Both respond to ACTH stimulation
with greater "vigor" than even cortisol. Allo-tetrahydrocorticosterone
is elevated in young female patients with eating disorders. Levels
of tetrahydrocorticosterone are elevated in depressed women,
yet significantly decreased in depressed men.
Both are useful in evaluating hypoaldosteronism.28,29
Enzyme activity, pre-determined by genetics or influenced exogenously
by medications or supplements, can play a very important role in determining
hormone safety in individuals. We are often hearing about supplements
and medications for improving clinical conditions such as weight loss
and hair loss, for improving estrogen metabolism, and for aiding post-cancer
treatment (aromasin, tamoxifen). By altering metabolic pathways and
up- or downregulating enzyme activity, what are we affecting on a cellular
level?
Urine testing not only measures the activity of specific enzymes, but
also gives information about downstream metabolites that are influenced
by various
endogenous hormones. By measuring downstream metabolites, we can better determine
the enzyme activity associated with each hormone. For example, if a patient
is taking saw palmetto, we can determine the effectiveness of the medication
by seeing a shift in the testosterone metabolized down the 5 beta DHT pathway
vs. the 5 alpha DHT pathway. Women who suffer from PCOS very frequently have
an upregulation in the 5 alpha reductase pathway – which is seen as an
increase in the downstream metabolites driven by this enzyme. This is pertinent
information and may help guide your diagnosis of this condition.
Urine testing additionally determines activity of 11 beta hydroxysteroid dehydrogenase
(11 b HSD), an enzyme with two isoenzymes (I and II) and bidirectional activity.
The isoenzyme, 11 b HSD1, facilitates the regeneration of active cortisol and
corticosterone (both 11 hydroxy glucocorticoids) from their inactive forms,
cortisone and 11 dehydrocorticosterone by oxidoreductase (11 b reductase) action.30
The reverse reaction facilitating inactivation of cortisol to cortisone is
affected by the 11 b HSD2 enzyme through 11 b dehydrogenation.31
Leptin-resistant Zucker obese rats have impaired 11 b HSD1 in the liver with
increased activity in the omental adipose tissue.32 Dysregulation of 11b HSD1
in human obesity has been recognized and appears to be tissue-specific. An
increase in BMI is associated with impaired 11b HSD1 activity, the degree of
impairment correlating with visceral fat mass.33 This downregulation of 11
b HSD1 activity in the obese could be protective against development of insulin
resistance. Like the genetically obese Leptin-resistant Zucker rats, obese
humans also demonstrate impairment of hepatic 11 b HSD1 activity, resulting
in decreased reactivation of corticosteroids, while 11 b HSD1 activity in subcutaneous
abdominal adipose tissue is increased.34,35 This increase in 11 b HSD1 in adipose
tissue might explain the proliferation of fat tissue and adverse metabolic
effects in obesity. Growth hormone replacement in growth hormone-deficient
patients results in reduction of body fat along with lowered ratio of cortisol
to cortisone in keeping with 11 b HSD1 inhibition.36 With the increase in insulin
resistance in the population, it is useful to have this added information via
urine testing when addressing the approach to treatment.
In women, 24-hour urine testing sometimes finds lower levels of estriol than
the sum of estrone and estradiol, which many population-based studies have
shown to be associated with increased breast cancer risk. Administration of
Lugol's iodine (six to eight drops daily and tapered according to response)
most frequently increases estriol and diminishes estrone and estradiol.37 Urine
testing can also help explain failure of BHRT to relieve menopausal symptoms.
In this circumstance, much higher than anticipated levels of all estrogens
are frequently found in the urine, a situation termed "hyperexcretion" or "failure
of hormone retention." Treatment with physiologic-dose (300-600 micrograms)
of cobalt chloride almost always corrects this situation, gradually reducing
urinary estrogen excretion towards normal, while menopausal symptoms gradually
fade.37
Hormone Use in Clinical
Practice with Urine Testing – Two Case
Studies
Seventy-two-year-old Frank came in to the office with complaints of
muscle weakness, lack of stamina, and erectile dysfunction. Among various
supplements,
he was taking 100 mg of pregnenolone. Pregnenolone is considered the "mother
of all steroids," as it is at the top of the steroid hormone tree and
may be converted to anything downstream (cortisol, estrogen, testosterone,
DHEA, etc.).
Twenty-four-hour urine testing via GC/MS determined his testosterone levels
to be on the very low end of normal, with the estrone fraction three times
as high as the testosterone values, at a level consistent with most premenopausal
females. Estradiol was within normal limits. The pregnenolone was discontinued,
and testosterone was given. Three months later, the gentleman returned with
improved stamina and muscle strength and had improvements in erectile function.
Urine studies confirmed a decrease in estrone and an increase in testosterone
values.
Fifteen-year-old Melissa came into the office with complaints of severe PMS,
weight gain, heavy menses, hirsutism, and acne. Twenty-four-hour urine collection
indicated estrogens and progesterone within normal limits, with a very elevated
DHEA and free testosterone fraction. The 11 beta HSD1 enzyme activity was increased,
and the 5 alpha reductase enzyme was also increased. The patient was put on
strict dietary recommendations for insulin resistance and given saw palmetto,
160 mg per day. The 5 alpha reductase enzyme activity was reduced, as well
as 5 alpha DHT on follow-up studies, and the patient noted a remarkable improvement
in acne, as well as hirsutism.
The safety of bio-identical hormone replacement therapy is continually evolving.
Fortunately, there are many studies to assist our understanding of their positive
nature and alleviate worry over side effects. However, the extent of how the
steroid hormones affect the body on a cellular level is not completely known.
Apprehension over the practice of BHRT can be lessened with adequate and comprehensive
testing methods, such as with the 24-hour urinalysis. The 24-hour urinalysis
measures the active form of steroid hormones, their metabolites, enzymes, and
ratios by GCMS method, a gold standard in the hormone-testing industry. This
information is extremely beneficial in aiding our diagnosis and decisions on
the use of appropriate hormone protocols.
Notes
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PM. The effects of oral and transdermal hormone replacement therapy
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Lacut K, Oger E, Le Gal G, Blouch MT, Abgrall JF, Kerlan V, Scarabin PY, Mottier
D; SARAH Investigators. Differential effects of oral and transdermal postmenopausal
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Post MS, Christella M, Thomassen LG, van der Mooren MJ, van Baal WM, Rosing
J, Kenemans P, Stehouwer CD. Effect of oral and transdermal estrogen replacement
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Thromb Vasc Biol. 2003;23(6):1116-21. Epub 2003 May 1.
Oger E, Alhenc-Gelas M, Lacut K, Blouch MT, Roudaut N, Kerlan V, Collet M,
Abgrall JF, Aiach M, Scarabin PY, Mottier D; SARAH Investigators. Differential
effects of oral and transdermal estrogen/progesterone regimens on sensitivity
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De Lignieres B, Basdevant A, Thomas G, et al. Biological effects of estradiol-17
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Scarabin PY, Alhenc-Gelas M, Plu-Bureau G, Taisne P, Agher R, Aiach M. Effects
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31. Ibid.
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36. Weaver JU, Thaventhiran L, Noonan K, et al. The effect of growth hormone
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37. Wright, JV. Bio-identical steroid hormone replacement: selected observations
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