Low testosterone and ed

PMC

Treatment With Testosterone

The clinical signs of hypogonadism in elderly men with ED can be improved with androgen treatment, although erectile function may not improve. Therefore, in men who have normal or borderline levels of serum testosterone, exogenous androgens may be given for a time to determine the efficacy of the treatment for both ED and non-ED signs and symptoms. In our clinic, we treat such patients for 3 months with exogenous testosterone to determine whether there is an effect on either the ED or the clinical signs of hypogonadism (if present). If the ED is not reversed, which is common,27,28 but the other aspects of hypogonadism are improved, it may be prudent to keep these men on exogenous testosterone as long as there are no contraindications to its use (Table 3).29–31

Table 3

Contraindications to Androgen Treatment

Absolute

  • Breast cancer (past or present)

  • Polycythemia

  • Prostate cancer (past or present)

  • Severe cardiac or coronary insufficiency

Relative

  • Hyperviscosity states

  • Lower urinary tract symptoms (prostatism)

  • Sleep apnea

There is currently little clinical evidence that exogenous androgen treatment will lead to prostate disease,3,31,32 such as benign prostatic hyperplasia or prostate cancer.33,34 In spite of this, androgen administration to men above age 50 requires careful monitoring of the prostate. A baseline digital rectal examination (DRE) and measurement of a prostate-specific antigen (PSA) level are recommended prior to starting exogenous androgen therapy. An abnormal DRE and/or an abnormal PSA requires further evaluation of the prostate to rule out prostate cancer before androgen therapy can be initiated.

Epidemiologic studies show that hypogonadal men are at higher risk for cardiovascular events than are normal men. Generally, there is an inverse correlation between testosterone levels and the atherogenic lipid profile, presence of atheromatosis,35,36 or degree of coronary artery stenosis37; androgen supplementation within the physiologic range normalizes the lipid profile, probably by increasing insulin sensitivity, and decreases HDL cholesterol with little effect on LDL cholesterol and triglycerides38 (the latter 2 being well-known risk factors for atherosclerosis). Testosterone also has complex effects on both the coagulation and fibrinolytic profiles; supraphysiologic levels of testosterone, nonaromatizable anabolic steroids, or alpha alkylated androgens are clearly atherogenic and often may cause cardiovascular accidents. 39–41 As a result, blood hematocrit levels should be determined before starting exogenous androgen therapy. Men with severe coronary disease are not candidates for androgen therapy.

The ideal testosterone replacement agent should:

  • Mimic diurnal patterns of adenogenous hormone secretion.

  • Produce physiologic levels of not only testosterone but also its metabolites: dihydrotestosterone (DHT) and estradiol (E2).

  • Be well tolerated, comfortable and convenient to use, and cost-effective. Medications available in the United States currently include oral, intramuscular, and transdermal agents (Table 4). Implantable testosterone pellets, while used abroad, are not currently available for treatment of patients in the United States.

    Table 4

    Clinically Available Testosterone Preparations

    • Parenteral injections (testosterone enanthate or testosterone cypionate): every 2–3 weeks

    • Oral, 17α-alkylated methyltestosterone: 10 – 40 mg daily (not recommended)

    • Scrotal patch: 5 mg daily (Testoderm)

    • Nonscrotal patch: 5 mg daily (Androderm)

    • Skin gel (Androgel)

Oral. Oral agents for testosterone replacement are clearly convenient and comfortable to use. Oral testosterone, however, is absorbed rapidly from the GI tract and circulates through the portal blood.42,43 Because of this portal circulation and rapid hepatic metabolism, only a small volume of testosterone is circulated, and only serum testosterone metabolites are raised. Most important, these agents have been reported to produce significant long-term hepatic toxicity.44 Oral testosterone does not reproduce the circadian pattern of testosterone production by the testes, nor does it achieve normal physiologic levels of DHT or estradiol.

An example of an active oral preparation is testosterone undecanoate; it is partially absorbed via the lymph, thus escaping first-pass hepatic inactivation. Testosterone undecanoate, unfortunately, is available only outside of the United States.45 The usual dose is 120 to 240 mg/d, divided over 2 or 3 doses. Absorption and plasma levels achieved are variable, but the compound restores serum testosterone levels and improves libido in hypogonadal men. Plasma estradiol levels also rise to physiologic levels with oral testosterone undecanoate treatment.

The most effective of oral agents of testosterone are the 17α alkylated testosterones, such as methyltestosterone. These 17α alkylated testosterones may be administered either orally or buccally but, because of their high cost, minimal potency, and risk of hepatotoxicity, these types of oral androgens should not be used clinically for androgen replacement.

Parenteral. Intramuscular preparations of testosterone are effective in increasing serum testosterone levels, although they produce significant elevations immediately after administration and a very low nadir before repeat injection. These parenteral androgens do not provide the normal circadian pattern of testosterone, and the injections are uncomfortable at times. Intramuscular testosterone can be administered in its aqueous, unmodified form; however, its rapid absorption and degradation make this form unsatisfactory for testosterone replacement. Similarly, while restoring serum DHT levels, estradiol levels may be excessive in patients with high testosterone levels after injection of aqueous, unmodified testosterone.

The 17β-hydroxyl esters of testosterone, however, are modifications of aqueous testosterone that are more widely used, can be administered with slow-release injection vehicles, and are more useful for testosterone replacement therapy. These 17β hydroxyl esters lack inherent androgenic activity and must be hydrolyzed to testosterone before they become active. Parenteral preparations of testosterone are usually administered in an oil-based vehicle, such as cottonseed or sesame oil. In the United States, the 17β-hydroxyl esters of testosterone include the short-acting testosterone propionate and longer-acting testosterones enanthate and cypionate. Because of the short activity of testosterone propionate, it is impractical to use; it must be injected every second day to maintain serum testosterone levels. In men requiring testosterone replacement, testosterones enanthate and cypionate may be administered every 2 to 3 weeks to maintain normal average testosterone levels.46–48 There are, however, surges in the serum testosterone level about 1 to 2 days after administration, sometimes reaching serum levels as high as 1400 ng/dL, which then decline over 14 to 21 days, reaching a nadir approximately at day 21. Because of these significant peaks and valleys in serum testosterone levels, patients may have mood swings and significant changes in sexual function.

Testosterones enanthate or cypionate may be administered in doses of 200, 300, or 400 mg every 2 to 4 weeks.48 The 200-mg injections maintain normal testosterone levels for approximately 2 weeks, while 300-mg levels will maintain serum testosterone levels in the eugonadal range for approximately 3 weeks. The 400-mg doses, while obtaining higher peak values, will not maintain eugonadal levels beyond the 3-week limit. In hypogonadal men, these agents will produce an improvement in libido, sexual function, potency, energy level, and mood if these abnormalities are due to the androgen depletion.42 Increased sexual aggressiveness and overall aggressive behavior during peak levels of injectable testosterone have been reported,46 and careful counseling about these mood and behavioral changes in patients undergoing injectable testosterone therapy is essential. These adverse effects are rare, however, and testosterone enanthate has become the most widely used agent for exogenous testosterone replacement in the United States. It is safe, cost-effective, and convenient.

Besides aggression, there are other side effects from androgen therapy, such as the development of an atherogenic lipid profile, insulin resistance, polycythemia, sleep apnea, fluid retention, acne, and hypertension.49 Supraphysiologic levels of testosterone in the blood lead to increased peripheral aromatization of testosterone to estradiol, and this may produce gynecomastia. 5,50,51

Patches. Because of concern that supraphysiologic levels of testosterone play a major role in the development of side effects from testosterone treatment, transdermal testosterone patches, notwithstanding their high cost, avoid supraphysiologic levels of testosterone and restore the normal diurnal testosterone pattern.52 Another advantage of the patch over the injection is that if and when any disturbing side effects from testosterone occur, the patches can be removed immediately.

Transdermal testosterone is currently available as a scrotal or nonscrotal patch.53 Transdermal vehicles use unmodified testosterone and are an alternative to intramuscular or oral medications. When applied prior to bedtime, these transdermal patch systems provide normal testosterone levels with diurnal variations in a physiologic fashion. Peak testosterone levels are achieved in the early morning, with a nadir prior to bedtime. While the scrotal patch (Testoderm) requires scrotal shaving weekly and increases DHT levels somewhat beyond the normal range, normal physiologic serum testosterone levels can be obtained. The nonscrotal transdermal patch (Androderm) also maintains a diurnal serum concentration curve with normal testosterone, estradiol, and DHT levels. Because testosterone levels do not increase beyond normal, the mood swings and aggressiveness that sometimes occur with intramuscular testosterone should not be seen with the transdermal preparations. While long-term studies are still unavailable on these issues, a smoother, more natural serum testosterone level can be obtained with the patches. Transdermal systems, however, are much more expensive than the parenteral preparations.

Clinical studies of these transdermal preparations demonstrate improved sexual function, libido, and nocturnal penile tumescence response, with normal hematocrit, lipid, and PSA levels. The side effect of dermatitis makes the transdermal agents inappropriate for some men.

Low Testosterone and ED

Understanding Low Testosterone

For most men, low testosterone is not the cause of their erectile dysfunction (ED).

What is Testosterone?

Testosterone is a naturally produced androgen hormone in both males and females, and it is the primary sex hormone in men. It is primarily produced by the testicles and is regulated by the pituitary gland and the hypothalamus. Testosterone is the hormone responsible for the development of male sex organs during the fetal stage and it drives the physical changes and transitions that occur during male puberty. In adult men, testosterone controls and maintains typical adult male characteristics and physical features.

  • Sex hormone produced in testes (reproductive glands)

  • Participates in modulation of sperm production

  • Maintains adult male characteristics and physical features

  • Affects sex drive and feelings of sexual desire

  • Impacts mood, energy level, muscle mass, and bone strength

The Myth of Low Testosterone and Erectile Dysfunction (ED)

Often, erectile dysfunction (ED) or male impotence is misdiagnosed as a testosterone-driven problem. While androgen does play a role in erections, there is a lack of clinical evidence linking low testosterone level to the inability to achieve or sustain an erection. Erectile dysfunction is most often a vascular problem, not a hormonal issue. More recently several well designed prospective studies have shown that even when replacing testosterone in men with ED and “low or borderline levels”, no improvement of erectile function occurs.

Research has proven two significant facts dispelling the direct correlation between low testosterone and ED problems:

  1. Normal erections do not require normal testosterone levels

  2. Increasing testosterone level does not increase frequency or strength of erections

Many times the reduced sexual desire that accompanies ED is misconstrued as low testosterone by a patient or his physician. It is common for men who experience prolonged sexual potency problems or erection difficulties to become disinterested in sex out of depression or avoidance, not a low level of testosterone. A state of resignation sets in men’s minds expressed by the following words: “Why bother…”

Further, age may be a factor in the hasty connection made between ED and low testosterone. As man ages, his testosterone level naturally declines by 1-2% each year. Likewise, aging can play a role in diminished sexual potency and the ability to achieve an erection. While these occurrences may be simultaneous, there is no proof that one causes the other.

Approximately 2% of total testosterone exists in the free or unbound form, and approximately 40% is tightly bound to sex hormone–binding globulin (SHBG). The remaining testosterone is weakly bound to albumin and other proteins. Free and albumin-bound testosterone are considered the active or bioavailable testosterone. Several medical conditions may cause free testosterone to be low when total testosterone appears to be normal. Also total testosterone may be low and free testosterone levels normal. When evaluating and treating men for low testosterone levels it is therefore important to measure both the free and total testosterone before initiating testosterone replacement therapy. Because testosterone levels vary greatly in the same individual depending on when it is measured therapy should not be initiated until several measurements are made.

Normal Verses Low Testosterone Levels

It is important to understand that testosterone is measured as a range, not a scale. Testosterone level is determined through a simple blood test and, since levels fluctuate throughout the day, a true reading can only be achieved with multiple tests on different days at varying times.

Normal male testosterone levels range from 300 to 1,200 nanograms per decileter. If your testosterone level tests at the lower end of this range it does not mean you have a low testosterone level. Again, these numbers are to be used as a range, not a scale, and testosterone level can very significantly by man and even by time of day.

Men are far more likely to have non-problematic, low-normal testosterone than they are to have true low testosterone, below 300 ng/dL.

Symptoms of Low Testosterone

Symptoms of low testosterone can only be diagnosed by a medical professional, but one suffering from a deficiency may notice erectile dysfunction, depression, anxiety, low sex drive, high cholesterol, weight gain, or problems concentrating. However, these symptoms are not specific for low testosterone levels and can be caused by many other factors. If it is determined that the patient is suffering from androgen deficiency, long term TRT may be initiated. Testosterone can be administered in gels, creams, pills, injections, or through an implant underneath the skin. Receiving the hormone orally is generally not the preferred route of delivery, as it is not well absorbed and may lead to complications in other organs such as the heart and liver. Transdermal delivery is currently the best way to replace testosterone.

Low testosterone, registering below 300 ng/dL, can be indicated by any number of the following symptoms:

  • Excessive tiredness and easy fatigue with exertion or exercise

  • Reduced sex drive

  • Fertility issues as the result of lowered sperm count

  • Irritability, moodiness, and depression

  • Body hair reduction

  • Reduced bone strength and/or muscle mass

  • Weight increase and/or increased body fat

  • Hot flashes or excessive sweating

It is important to remember that many symptoms of low testosterone are common aging symptoms, as well associated with conditions such as diabetes, heart disease, and primary depression, the metabolic syndrome, renal disease and hypertension.

What Causes Low Testosterone?

Low testosterone, confirmed through a blood test, can be caused by a variety of medical issues. Prior to beginning any treatment, your physician will attempt to rule out disease or another serious medical problem as the cause.

Testosterone levels can be lowered by:

  • High blood pressure

  • High cholesterol

  • History of pituitary or thyroid issues

  • Kidney problems

  • Obesity

  • Osteoporosis

  • Pulmonary disease or asthma

  • Steroid exposure

  • Type 2 diabetes

Testosterone Replacement Therapy

Unfortunately, testosterone supplementation does not exist. Studies repeatedly show Androgen Replacement Therapy (ART), also called Testosterone Replacement Therapy (TRT) or Hormone Replacement Therapy (HRT), is an ineffective form of ED treatment.

Men with confirmed low testosterone levels may be advised to begin a testosterone replacement regimen. Treatment choices include topical gels, pills, injections, and patches. Topical gels, such as AngroGel, Testim or Axyron are most often prescribed and are applied to the shoulders and upper body, allowing the testosterone to be absorbed through the skin.

Whenever testosterone is added to the male human body, it causes a cessation of ones natural testosterone, shrinkage of testicle and sterility. Therefore this should never be given to young men contemplating fatherhood, as the effects of long-term therapy may be permanent.
Small subsets of men actually choose to undergo testosterone replacement therapy, which for some patients restores energy and sex drive. It is important to note that testosterone replacement therapy, or TRT, should only be reserved for the most severe of cases, and this treatment option should always be discussed with Dr. Eid, who can properly diagnose you with a deficiency.
At our office, we will measure the total and free testosterone in your blood, and will likely measure prolactin (to assess the function of the pituitary gland), as well as SHBG, FSH, LH, and thyroid levels. Testosterone levels normally falls between 250-800 nanograms per deciliter of blood. However, this level will vary even for the same person, depending on exercise and time of day, as well as other factors.

Dangers of Testosterone Replacement Therapy

Currently, testosterone cannot be supplemented. Low testosterone treatments are designed to replace the body’s natural production of testosterone and could permanently cease the body’s ability to produce testosterone naturally. Unfortunately, extensive marketing from the pharmaceutical industry encourages the widespread use of testosterone replacement. The aggressive pressure they place on physicians to prescribe testosterone borders on medical irresponsibility. The long-term dangers of inappropriate testosterone use could be far more severe than we know today.

The potential, negative side effects of testosterone treatment should be discussed in detail with your physician. Men must carefully weigh the benefits and risks prior to beginning treatment.

Immediate physical reactions may include:

  • Increased appetite

  • Mood alterations

  • Nausea

  • Vomiting

Note: Men often mistake the increased energy and improved mood they experience while using testosterone replacement as proof of its effectiveness. In reality, the steroidal nature of testosterone is what causes these changes. Once the treatment is stopped, men can experience withdrawal and severe depression, as well as the permanent inability to naturally produce testosterone.

Longer-term effects may include:

  • Permanent dependence on testosterone replacement therapy

  • Difficulty urinating

  • Increase in red blood cell count and thickening of blood

  • Fluid retention, liver problems, blood clots, and stroke

  • Increased growth of prostate tissue

  • Prostate cancer tumor growth

  • Sperm count reduction leading to permanent infertility

  • Permanent irreversible suppression of natural production of testosterone

  • Shrinking of the testicles

  • Increased resistance to testosterone replacement

More severe side effects include priapism (an erection that does not go away, and requires medical attention), liver damage, and swelling. In addition, TRT should be used cautiously, and is not the ideal treatment for most healthy adult men with low normal testosterone levels. It should not be used in patients with heart disease or prostate cancer, those with known prostate problems, or men with high cholesterol. In addition, treatment with testosterone may activate prostate cancer in men with undiagnosed cancer. So men considering this treatment should be screened for prostrate cancer, as well as have future screenings.

Once started, it is extremely difficult to stop testosterone therapy. In essence, complete dependence or even addiction to it may occur over time. The long-term effects of testosterone therapy are continually being studied.

Results and efficacy

Almost all of the clinical trials studying TRT have been inconclusive or have not followed patients long-term, so this treatment option is still a bit experimental in practice, and the treatment should not be administered to anyone not deemed an exceptional candidate. Because of the serious nature of TRT, patients with less severe testosterone deficiencies may look into safer, alternative treatment options. Any man currently taking TRT needs to see their doctor regularly for checkups, and should report any medical issues immediately. In addition, prostate screenings are essential.

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ED vs. Low T…do you know the difference?

ED (erectile dysfunction) and Low T (low testosterone) are both common issues affecting millions of men today. Even though they share similar symptoms, they are actually two separate conditions.

ED is defined by the inability of a man to attain and/or maintain an erection sufficient for intercourse. Low T means the testicles are not producing enough of the male hormone testosterone.

Here’s what causes some confusion: Low T can cause ED, and while you can have Low T, you may not always suffer from ED. And you can also suffer from ED with normal testosterone levels.

Still confused? Here are some facts about each:

ED Facts

  • There is about a 50% chance of having some degree of ED between ages 40 and 70, after 70 the odds increase
  • The most frequent cause is poor circulation of blood to the penis, suggesting that ED can be a red flag for early heart disease
  • 25% of men with high blood pressure are affected
  • 17% of men with diabetes are affected
  • Treatment may include lifestyle changes such as losing weight, exercising, not smoking, avoiding drugs and alcohol, as well as medication and/or testosterone replacement therapy

Low T Facts

  • Natural testosterone production begins to decrease around age 40
  • About 10% of men ages 40 to 60 have Low T, and about 20% have it after age 60
  • Common causes include fatigue and depression
  • Low or diminished sex drive is a frequent indicator of Low T
  • Treatment usually includes testosterone replacement therapy

Along with older age, similar triggers for each ED and Low T are diabetes, depression and obesity. If you feel you are suffering from either condition, talk to your doctor because both ED and Low T can signify a more serious underlying medical condition.

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The Low-Down on Testosterone and Its Role in Erectile Dysfunction

As a man, your testosterone levels are closely linked to your sexual function but is low-T the reason for your erectile dysfunction? It may seem logical that low levels of testosterone might contribute to impotence but, in reality, this is rarely the case. In fact, many men who experience erectile dysfunction have normal levels of this essential male hormone.

So, what role does testosterone really play in male reproductive health and does it really have an effect on your sexual performance? Here’s what you need to know about testosterone and its relationship to erectile dysfunction.

Everything You Need to Know About Testosterone

According to the American Urological Association, about 1 in 5 men over the age of 60 have low testosterone levels but this is a problem that affects younger men as well. In fact, by the time you hit 30, your testosterone levels are probably already on their way down. Whereas a woman’s estrogen level eventually reaches zero during menopause, a man’s testosterone level never bottoms out but declining levels of this hormone may contribute to physical symptoms including daytime fatigue, loss of muscle mass, and low sex drive.

Testosterone is a male sex hormone that belongs to a class of hormones known as androgens. This hormone is primarily produced in the testes, though the adrenal glands produce a little bit as well. Testosterone production is regulated by the hypothalamus in the brain which sends a message to the pituitary gland – the pituitary gland then passes the message along to the testes to stimulate testosterone production. Prior to birth, testosterone plays a role in the development of male sex organs and, at puberty, it is involved in developing secondary sex characteristics such as the growth of body hair and facial hair, the deepening of the voice, and increased penis and testes size.

In addition to its role in the development of male characteristics, testosterone is also involved in sperm production and sex drive. Low testosterone levels have been associated with erectile dysfunction, reduced sperm count, loss of muscle mass or hair, reduced sex drive, and increased breast size. Just because erectile dysfunction may be a symptom of low testosterone levels, however, doesn’t mean that low-T causes ED. Keep reading to learn why.

Debunking the Myth About Low-T and Erectile Dysfunction

Low testosterone levels may affect your sex drive and your ability to reach orgasm, but they do not have a physiological impact on your ability to achieve or maintain an erection. It is important to understand that erectile dysfunction is primarily a vascular issue, not a hormonal one. In order to achieve an erection, you must have adequate blood flow to the penis and that requires a healthy heart and strong circulation – your testosterone levels don’t have anything to do with this.

Though researchers still don’t fully understand the relationship between testosterone and erectile dysfunction, they know two things for certain:

  1. Normal testosterone levels are not required to achieve a normal erection.
  2. Increasing testosterone levels (such as with testosterone therapy) does not increase the strength or frequency of erections.

Though low-T does not necessarily cause erectile dysfunction, many of the contributing factors for both conditions overlap. For example, low testosterone can be caused by high blood pressure, obesity, high cholesterol, and type 2 diabetes. These and other conditions have been identified as risk factors for erectile dysfunction, particularly in regard to their effect on nerve and vascular function.

The Dangers of Testosterone Replacement Therapy

By now it should be clear to you that your testosterone levels are not to blame for your erectile dysfunction but low-T can contribute to symptoms unpleasant enough that you may want to seek treatment. In addition to affecting your sex drive, low testosterone may cause the following:

  • Hair loss
  • Extreme fatigue
  • Loss of muscle mass
  • Increased body fat
  • Decreased bone mass
  • Changes in mood
  • Difficulty concentrating

In cases where these symptoms because severe enough to warrant treatment, testosterone replacement therapy is an option. Unfortunately, there is no way to supplement your body’s natural testosterone production but testosterone replacement therapy (TRT), or hormone replacement therapy (HRT), does exist. Treatment options include medications, topical gels, patches, and injections.

Though testosterone replacement therapy may boost testosterone levels, it is generally only recommended as a short-term treatment because it comes with a high risk for side effects. It is also worth noting that the long-term safety of TRT is still being studied. Interestingly, testosterone replacement therapy might actually reduce your sperm count and these effects could be permanent. Short-term side effects of TRT may include increased appetite, changes in mood, nausea, and vomiting. In addition to reduced sperm count or permanent sterility, some of the long-term effects of TRT may include the following:

  • Difficulty urinating
  • Increase in red blood cell count
  • Liver problems
  • Prostate tissue growth and/or tumors
  • Fluid retention
  • Shrinking of the testicles
  • Permanent dependence on TRT

Testosterone hormone replacement may also cause your body’s natural testosterone production to stop – this too may be irreversible. For all of these reasons, you need to think very carefully and consult your doctor before even considering TRT as an option. This treatment is typically reserved for older men with low-T and those experiencing extreme fatigue. If you want to become a father someday, TRT could make that impossible, so be careful.

Although testosterone replacement therapy is generally not a smart choice for younger men, you do have other options. If obesity is a factor, losing weight may boost your natural testosterone production. Short periods of high-intensity exercise have also been shown to elevate testosterone levels. Increasing your intake of certain nutrients such as zinc, Vitamin D, healthy fats, and branch chain amino acids (BCAAs) are beneficial for healthy testosterone production and limiting your intake of refined sugar will help you out as well.

Though low-T may not be the cause for your erectile dysfunction, testosterone definitely plays an important role in your sexual health and libido. If you’re concerned about your testosterone levels, talk to your doctor about getting a blood test to see whether your levels are within the normal range. If not, consider natural options for boosting your body’s testosterone production before you even think about testosterone replacement therapy. You may be surprised to learn that some of the simplest changes to your lifestyle and diet might have the biggest benefit.

Low free testosterone linked with ED in post-RP males

Chicago-A recent study found low levels of free testosterone in older men with prostate cancer could increase these men’s odds of facing erectile dysfunction after undergoing radical prostatectomy.

The study, presented at the AUA annual meeting in Chicago, indicated low levels of free testosterone have a negative effect on erectile function in men older than 60 years of age who have prostate cancer—and the effect worsens with age, researchers from the department of urology at the University of California Irvine found.

As a result, the authors recommend obtaining free testosterone levels in all men over the age of 60 years who are preparing to undergo radical prostatectomy. These levels could be used to predict recovery of sexual function after surgery.

In fact, “Maybe we should be treating free testosterone even if there are no symptoms now, because there could be symptoms of erectile dysfunction later,” Maxwell Towe, BS, a clinical research fellow at University of California Irvine, told Urology Times.

Also see: Nomograms predict erectile function recovery

Testosterone deficiency is associated with significant health problems in adult men, including obesity, diabetes, and hypertension. Low levels of total testosterone are one of the diagnostic criteria for hypogonadism. However, current clinical guidelines do not account for the impact of free testosterone levels on sexual dysfunction, even though levels of free testosterone are known to decrease as men age, while the prevalence of hypogonadism increases with age as well.

With this in mind, the authors sought to understand the relationships between free testosterone and sexual function in middle-aged-to-older men with prostate cancer.

The authors studied 820 men who underwent robot-assisted radical prostatectomy for primary treatment of localized prostate cancer. Preoperative evaluations included assessment of sexual function through International Index of Erectile Function (IIEF-5) scores and measurement of baseline sex hormone levels, including total testosterone, sex-hormone binding globulin, and free testosterone. The authors also studied the impact of age, body mass index, and pathologic grade on sexual function.

Next: Age an independent predictor of sexual function in both cohorts

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