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1.
《The aging male》2013,16(3):147-169
Abstract

Objective: At present, calculated free testosterone assessment is considered as the gold standard in diagnosing male hypogonadism. However, this assessment is not available for all the individuals diagnosed with decreased testicular function. The investigators of this study were, thus, prompted to evaluate whether the androgen deficiency in the aging male (ADAM) and the Massachusetts Male Ageing Study (MMAS) questionnaires could be used to replace biochemical parameters in the diagnosis for hypogonadism in men aged 40 years and above.

Methods: We evaluated 460 men, aged 40 years and above, all volunteers of a screening program for prostate cancer based at the Hospital de Clínicas of Porto Alegre. In this study, we assessed the efficiency of the ADAM and MMAS questionnaires in diagnosing Brazilian men with low levels of total, calculated free and bioavailable testosterone.

Results: The sensitivity of the ADAM questionnaire in diagnosing the calculated free testosterone was 73.6%, whereas specificity was 31.9%. ADAM could be used to properly classify our cohort into normal or hypogonadal individuals in 52.75% of the cases. The sensitivity of the MMAS questionnaire was 59.9%, whereas the specificity was 42.9%, resulting in a successful classification of 51.4% of the patients.

Conclusion: The ADAM and MMAS questionnaires showed adequate sensitivity in diagnosing male patients with low levels of free testosterone. However, because of the lack of specificity, these tools cannot replace calculated free testosterone assessments in men aged 40 years and above.  相似文献   

2.
Objective.?The aim of this study was to evaluate the association between serum levels of testosterone and free testosterone to lifestyle in aging males.

Methods.?Men between 45 and 85 years were assessed regarding body mass index (BMI), nicotine and alcohol consumption, stress level, physical and social activity, and sleeping quality by a self-administered questionnaire. In parallel, serum levels of testosterone (T), free testosterone (fT), LH, FSH, DHEA-S, E2 and SHBG were obtained.

Results.?In total, 375 men with a mean age of 59.9 years (9.2 ± SD) entered this study; 25.4% and 27.4% had hypogonadal testosterone or free testosterone serum levels, respectively. Nicotine consumption (smokers had higher levels of T and fT; p < 0.01), BMI (negative correlation to T; p < 0.01) and age (negative correlation to fT; p < 0.001) correlated with serum levels of testosterone or free testosterone. Physical and social activity, nicotine and alcohol consumption, stress level and sleep quality did not show a significant association with serum androgen levels.

Conclusion.?This prospective study of 375 men aged 45 to 85 years confirms the correlation between age, BMI and smoking with serum levels of testosterone and free testosterone, whereas the investigated variety of lifestyle factors did not show a significant association to serum androgen levels.  相似文献   

3.
Objective: This study set out to assess effects of testosterone replacement therapy (TRT) on parameters of metabolic syndrome and vascular function in obese hypogonadal males with type 2 diabetes mellitus (DM2).

Study design: Fifty-five obese hypogonadal diabetic males on oral hypoglycemic treatment were enrolled into this one-year, double-blind, randomized, placebo-controlled clinical study. Group T (n?=?28) was treated with testosterone undecanoate (1000?mg i.m. every 10?weeks) while group P (n?=?27) received placebo.

Methods: Anthropometrical and vascular measurements – flow-mediated dilatation (FMD) and intima media thickness (IMT) – biochemical and hormonal blood sample analyses were performed at the start of the study and after one year. Derived parameters (BMI, HOMA-IR, calculated free testosterone (cFT) and bioavailable testosterone (BT)) were calculated.

Results: TRT resulted in reduction of HOMA-IR by 4.64?±?4.25 (p?p?p?=?.005).

Conclusion: TRT normalized serum testosterone levels, improved glycemic control and endothelial function while exerting no ill effects on the study population.  相似文献   

4.
《The aging male》2013,16(4):249-256
Abstract

Background. Symptoms of late-onset hypogonadism (LOH) and concentrations of testosterone (T) and bioavailable testosterone (BT) were studied in relation to the data from the same men 5 years earlier.

Methods.?In 2008, 282 men, aged 60–82 years, answered a questionnaire regarding demographic data, medical history, different symptoms of LOH and the 10 questions from the ‘Androgen Decline in Aging Males (ADAM)-questionnaire’. Blood samples were analysed for concentrations of T and calculations were made for BT.

Results.?A total of 87.2% of the questionnaires were returned and analysed, and 75.2% of the responders gave blood samples. The oldest third of the men were most affected by LOH symptoms (p?<?0.05). Both T and BT concentrations decreased during the 5 years (p?<?0.05) but only the symptom ‘less strong erections’ changed significantly (p?<?0.05). Men reporting one of the four specific symptoms from the ‘ADAM-questionnaire’ for the first time in 2008 had a higher loss of T and BT than men who had unchanged or fewer symptoms than that reported in 2003.

Conclusions.?The magnitude of the decrease in concentrations is a better predictor of LOH than are the actual concentrations of T and BT. A combination of symptoms predicts LOH better than any single symptom.  相似文献   

5.
6.
《The aging male》2013,16(3):190-194
Objective.?There are few reports on the prognosis of patients receiving androgen replacement therapy (ART). In this study, we evaluated the subsequent symptoms of Japanese hypogonadal patients who had received ART, within several years previously by mail-in survey.

Methods.?Thirty-three aged men with symptoms of hypogonadism and testosterone deficiency who had received ART for 6 months responded to this survey. The survey consisted of questions associated with present physical and mental status and desire to resume ART. The Aging male’s symptoms (AMS) scale, IIEF-5 and SF-36 were also evaluated at pre-initiation, termination of ART and the time of the survey.

Results.?The mean duration from the last treatment was 55 months. Compared with the treatment period, more than half of patients (57.5%) answered that their present condition was better. Scores on the AMS scale, IIEF and SF-36 were all improved significantly in the early stages of treatment and not worsened a long period of time after ART was discontinued.

Conclusions.?For symptomatic Japanese hypogonadal patients, subjective effects of treatment were observed during the early treatment period and remained unchanged after discontinuation of ART. A short treatment period may thus be adequate in Japanese hypogonadal patients as regards symptomatic changes.  相似文献   

7.
Objective. We examined age associated variation in salivary testosterone values among Japanese males as well as anthropometric measurements.

Methods. Salivary samples were collected in pretreated sodium azide treated tubes. The first series: 15–79-year-old males (n = 99); two morning and two evening samples were collected at home for two days. The second series: 90-year-old males (n = 29); one morning sample was collected. Testosterone values were determined using an iodine125-based radioimmunoassay kit modified for saliva.

Results. Results show 1) a significant decrease in salivary testosterone values from 20s to 40s and older, 2) no significant decline after 40 through 90 years old, 3) no significant age-related differences in the degree of intraindividual diurnal fluctuation across age groups of 40–70s, and 4) higher BMI is associated with the lower salivary testosterone among 40–70s.

Conclusions. These results suggest that neither a constant decrease of salivary testosterone values or markedly reduced intraindividual fluctations are universal aspects of aging. Older males may maintain relatively high testosterone levels compared to younger men and a relatively ‘robust’ neuroendocrinological system.  相似文献   

8.
Objectives. In 2004, the Ontario Society of Clinical Chemists (OSCC) held an invitational multidisciplinary workshop to establish the most reliable, cost-effective approach to the biochemical assessment of hypogonadism in men.

Methods. Specialists across Canada in clinical biochemistry, endocrinology, family medicine and urology were invited to participate in this workshop which included individual presentations and a consensus component addressing two challenge statements: 1) ‘Determinations for total testosterone (TT) are equivalent to those for bioavailable testosterone (BAT) or calculated BAT (cBAT) or free testosterone (FT) (by analogue radioimmunoassay or equilibrium dialysis) or calculated FT (cFT)’; 2) ‘There is no good evidence that borderline low testosterone concentrations in men should be treated’. The main outcomes were to identify what agreement exists in Canada, what issues were still controversial, and what research remains to be addressed.

Results. Six recommendations based on expert opinion addressed these main themes: investigate with morning total testosterone (TT) followed by repetition and reflexive testing of sex hormone binding globulin (SHBG) if testosterone is 8–15 nmol/L with automatic calculation of cBAT; discontinue the use of analogue free testosterone assays; and definitive methods and standards must be available to ensure standardized results.

Conclusions. Total testosterone is a reliable marker for the initial investigation of men presenting with symptoms of hypogonadism; cBAT is a reasonable follow-up test in patients with equivocal biochemical or consistent symptomatic findings.  相似文献   

9.
《The aging male》2013,16(3):179-183
Objective.?This study assessed the possible associations between lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) in aging Taiwanese males and investigated the impact of various aspects of LUTS on ED.

Methods.?A free health screening for aging males (≥40 years old) was conducted in Kaohsiung Medical University Hospital. All the subjects had completed clinical data and answered questionnaires. ED and LUTS were assessed by validated symptom scales: the International Index of Erectile Function-5 (IIEF-5) and the International Prostate Symptom Score (IPSS).

Results.?A total of 339 eligible patients enrolled in this study with a mean age of 60.1 years old. In multiple logistic regression analysis, age and IPSS (p?<?0.001 and p?=?0.013, respectively) were significantly associated with ED after controlling other comorbidities. In a further age-adjusted multiple regression analysis, our results showed that irritative symptoms (p?=?0.042) have a more significant association with ED than the obstructive symptoms (p?=?0.101).

Conclusions.?Our results indicate that age and LUTS are the two most independent risk factors for ED. Aging Taiwanese males with LUTS are at increasing risk for ED, especially for those with significant irritative symptoms.  相似文献   

10.
The accurate measurement of testosterone remains a challenge. The determination of the blood testosterone concentrations in serum by conventional immunoassays is inaccurate in men and even more so in females and children. A new luminescence enzyme immunoassay (LIA) has been developed and validated. The high analytical (8.7 pmol/L) and functional (17.3 pmol/L) sensitivity allows the quantification of the very low concentration in saliva, as well as in serum, after 1/40 dilution. This study measured salivary testosterone levels and compared the results with the free levels calculated from total testosterone and sex hormone-binding globulin in eugonadal and hypogonadal men. Salivary testosterone concentrations in healthy men in morning hours were 369 pmol/L (mean), range 263–544 pmol/L, which was statistically significantly higher than that in men with androgen deficiency, 215 pmol/L (mean), range 51–249 pmol/L.

Repetitive determination of free testosterone concentrations in saliva (once a week for 5 weeks) showed high stability of results over time, with coefficient of variation 9% (range 5–23%).

In this study we showed that free salivary testosterone levels in morning samples correlated well with calculated free testosterone in blood, both in healthy men (R = 0.754, P = 0.001), and in patients with androgen deficiency (R = 0.889, P = 0.0001), though in cases with very low testosterone, salivary concentrations were systematically higher than calculated free testosterone levels in blood.  相似文献   

11.
《The aging male》2013,16(2):132-140
Introduction.?Although testosterone and its association with disease progression and mortality is a widely studied topic, no studies have evaluated mortality risks related to testosterone levels in an older African-American population. The mechanisms for known racial differences in mortality risk for certain cancers and cardiovascular risk factors are largely unknown. Elucidating a mortality risk associated with testosterone levels may give insight into the elevated risk for certain diseases in African-Americans.

Methods and results.?Study data were derived from a cohort 622 African-Americans (age 80.05?±?6.4, range 68–102) from Saint Louis, Missouri that includes 190 males (age 79.38?±?6.2, range 70–102). The eligible sample for this report includes 56 of the 190 males (age 78.89?±?6.9, range 70–102) who donated blood at baseline in 1992–1994 and subsequently tested for total testosterone and bioavailable testosterone. Covariates for adjusted analyses were lower body functional limitations, physician visits and comorbidities, also collected at baseline. Males' mean bioavailable testosterone levels (ng/dl) were 33.33?±?24.4 (n above 70?ng/dl?=?5) and mean total testosterone levels (ng/dl) were 246.63?±?118.7 (n above 300?ng/dl?=?20). Vital status was determined through 2002; 41 males (73%) were deceased and 15 were alive. Mortality did not differ among males with testosterone levels?<300 versus 300+ (p?=?0.42) or with bioavailable testosterone levels?<70 versus > 70 (p?=?0.34). Total testosterone levels did not predict mortality when adjusted for age (Adjusted Hazard Ratio [AHR]?=?0.998; 95% confidence interval [CI] 0.995–1.001; p?=?0.28) or adjusted for age and other covariates (AHR?=?0.099; 95% CI 0.996, 1.002; p?=?0.35). Bioavailable testosterone levels did not predict mortality when adjusted for age (AHR?=?0.992; 95% CI .977–1.007; p?=?0.30) or when adjusted for age and other covariates (AHR 0.991; 95% CI .976–1.006; p?=?0.261).

Conclusion.?In older African-American males, total and bioavailable testosterone levels, with and without adjustment for covariates, are not independently associated with mortality risk.  相似文献   

12.
《The aging male》2013,16(4):95-99
Background.?It is well documented that testosterone levels decline with age, this decline is associated with symptoms which could be assessed denoting androgen deficiency. We investigated the validity of an Arabic version of the Saint Louis University androgen deficiency in ageing men (ADAM) questionnaire to screen for androgen deficiency in Saudi and non Saudi Arabic speaking men.

Methods.?It was a cross sectional study of ambulatory community-based Arabic Saudi men recruited from Volunteers in Riyadh city, Capital of Saudi Arabia, aged 18–80 years. Seven hundred thirty men agreed to fill the Arabic ADAM questionnaire, they were invited to a morning blood sample for total testosterone and sex hormone binding globulin and those who agreed to complete the whole study were only 407 men. Low serum bioavailable testosterone (BT) levels (androgen deficiency) were defined as <10th percentile of serum BT levels in young healthy Saudi men (18–30 years).

Results.?Cronbach's Alpha of 0.71 (n?=?730) showed a good internal consistency of the Arabic ADAM questionnaire. Among participants, 18.2% and 77.6% had low serum BT levels and a positive ADAM questionnaire, respectively. The prevalence of positive ADAM and low serum BT is increasing with age. The Arabic ADAM questionnaire had a high sensitivity of 86.5%, a low specificity of 24.3%, and positive predictive values (+PVs) and negative (?PVs) of 20.3% and 89%, respectively.

Conclusion.?The Arabic ADAM questionnaire has a very good sensitivity but very low specificity for screening of androgen deficiency in Saudi men, therefore biological confirmation is needed especially when clinical symptoms of androgen deficiency are present.  相似文献   

13.
《The aging male》2013,16(1):53-58
Purpose.?We performed a randomised controlled study regarding the effects of androgen replacement therapy (ART) on lower urinary tract symptoms (LUTS) in hypogonadal men with benign prostate hypertrophy (BPH).

Methods.?Fifty-two patients with hypogonadism and BPH were randomly assigned to receive testosterone (ART group) as 250?mg of testosterone enanthate every 4 weeks or to the untreated control group. We compared International Prostate Symptom Score (IPSS), uroflowmetry data, post-voiding residual volume (PVR) and systemic muscle volume at baseline and 12 months after treatment.

Results.?Forty-six patients (ART group, n?=?23; control, n?=?23) were included in the analysis. At the 12-month visit, IPSS showed a significant decrease compared with baseline in the ART group (15.7?±?8.7 vs. 12.5?±?9.5; p?<?0.05). No significant changes were observed in the control group. The ART group also showed improvement in maximum flow rate and voided volume (p?<?0.05), whereas no significant improvements were observed in the controls. PVR showed no significant changes in either group. In addition, the ART group showed significant enhancement of mean muscle volume (p?<?0.05), whereas no significant changes were seen in the controls.

Conclusion.?ART improved LUTS in hypogonadal men with mild BPH.  相似文献   

14.
Objective.?To test the relationship between gonadal status and objective measures and determinants of physical performance in older men and their determinants.

Methods.?The study included 455?≥?65 year older men of InCHIANTI study, Italy, with complete data on testosterone levels, hand grip strength, cross-sectional muscle area (CSMA), short physical performance battery (SPPB). Linear models were used to test the relationship between gonadal status and determinants of physical performance.

Results.?Three different groups of older men were created: (1) severely hypogonadal (N?=?23), total testosterone levels ≤230?ng /dl; (2) moderately hypogonadal (N?=?88), total testosterone >230 and?N?=?344), testosterone levels ≥350?ng/dl. With increased severity of hypogonadal status, participants were significantly older while their BMI was substantially similar. In the age and BMI adjusted analysis, there was a significant difference in haemoglobin levels, hand grip strength and SPPB score (p for trend?p for trend?=?0.004) and haemoglobin (p for trend?Conclusions.?In older men, gonadal status is independently associated with some determinants (haemoglobin and muscle strength) of physical performance.  相似文献   

15.
《The aging male》2013,16(1):37-48
Aims.?To investigate the association between endogenous testosterone levels and psychological health symptoms in men from a general population.

Methods.?Total testosterone and sex hormone-binding globulin levels were analysed and free testosterone levels was calculated in 3413 men participating in the fifth Tromsø study in 2001. Self-administered questionnaires including information about education, marital status, smoking habits and the Hopkins Symptom Checklist-10 (SCL-10, a 10-item psychological health questionnaire) were completed. The cross-sectional data were analysed with partial association and analysis of variance and covariance.

Results.?The complete SCL-10 was not associated with total or free testosterone, but symptoms of anxiety were negatively associated with both total and free testosterone (p?p?=?0.021), before and after adjusting for age, waist circumference, marital status, education and smoking. There was an even stronger association between men presumed to be testosterone deficient and symptoms of anxiety (p?Conclusions.?Men presumed being testosterone deficient had a higher symptom score, in particularly regarding anxiety, but they did not have pathological symptoms. Thus, lower testosterone levels was only associated with subthreshold symptoms of anxiety and depression.  相似文献   

16.
Objective: We investigated the effects of testosterone replacement therapy (TRT) on bone mineral density (BMD) among hypogonadal men with osteopenia/osteoporosis.

Methods: From our previous EARTH study population, 74 patients with a clinical diagnosis of osteopenia or osteoporosis and hypogonadism were included in this study, as the TRT (n?=?35) and control (n?=?34) groups. The TRT group was administered 250?mg of testosterone enanthate injection every 4 weeks for 12 months. The BMD, waist circumference, body mass index, body fat percentage, and muscle volume were measured at baseline and at 12 months. Blood biochemical data, including total cholesterol, triglycerides, HDL-cholesterol, hemoglobin A1c, and adiponectin values were also evaluated.

Results: At the 12-month visit, BMD significantly increased in both groups. However, comparisons on changes of parameter values from baseline to the 12-month visit between the TRT and control groups were significantly different in BMD (5.0?±?5.0 vs. 3.0?±?3.2; p?=?.0434) and in adiponectin value (?0.90?±?3.33 vs. 0.10?±?2.04; p?=?.0192). There were no significant changes in other parameters.

Conclusions: TRT for 12 months could improve BMD with a decrease in adiponectin levels among hypogonadal men with osteopenia/osteoporosis.  相似文献   

17.
Obese men may present hypogonadothrofic hypogonadism, mainly related to higher insulinemia and aromatase activity. Our objectives were to evaluate the relationship of sex-hormones profiles and frequency of depressive symptoms in 43 obese men, in a cross-sectional study. They had 19–60 years, and body mass index 30–50?kg/m2. LH, total and free testosterone (TT and FT), estradiol (E2), sex hormone binding globulin, estradiol/total testosterone ratio (E2/T) were analyzed. Depressive symptoms were evaluated by “beck depression inventory” (BDI), and significant depression was considered if BDI?≥?16.Thirty-four (80%) presented low TT levels, but only 4 (14%) had low free testosterone and hypogonadism symptoms; 12 of 43 (28%) presented increased E2. Forty five (56%) presented depressive symptoms, but 16 (28% of the 45) had significant depression. BDI correlated positively with E2 (r?=?0.407; p?=?0.001) and E2/T (r?=?0.473; p?=?0.001), but not TT or FT. Patients with significant depressive showed higher levels of estradiol (136?±?48 versus 103?±?48?pg/ml, p?=?0.02) and E2/T (16.0?±?9.9 versus 9.8?±?4.6; p?=?0.002) (mean?±?SD).In conclusion, obese men may present relatively excess of estradiol and deficiency in testosterone, leading to an imbalance between these two hormones. The greater this imbalance, the more depressive symptoms had our patients.  相似文献   

18.
《The aging male》2013,16(1):52-56
Introduction: After middle age, some men show androgen-deficiency symptoms leading to so-called PADAM (partial androgen deficiency in aging males). We tested the oral form of testosterone, testosterone undecanoate (Andriol®, NV Organon, The Netherlands), in men with PADAM and evaluated its efficacy and safety in Korean male patients. Methods: We included those patients with the clinical symptoms of PADAM who had decreased levels of serum total testosterone (< 2.8 ng/ml) or free testosterone (< 13 pg/ml). We excluded patients with biopsy-confirmed prostrate cancer, abnormal findings in digital rectal examination or prostate specific antigen testing (until prostrate cancer was ruled out), breast cancer, severe voiding symptoms and secondary hypogonadism. At the first visit, the International Prostate Symptom Score (IPSS), International Index of Erectile Function (IIEF) and Korean Andropause Questionnaires were administered; complete blood count, the lipid profile, and levels of total and free testosterone, prolactin, luteinizing hormone, follicle stimulating hormone and prostate specific antigen were measured and a digital rectal examination was given. Patients were administered oral testosterone undecanoate 160 mg daily for 3 weeks. The dosage was then decreased to 80 mg daily and changes in symptoms were assessed at every visit. After 3 months, serum tests, including testosterone, were repeated. Results: We evaluated 28 patients who had received testosterone undecanoate for more than 3 months. The patients' mean age was 56.1 (48-68) years. The score of the Korean Andropause Questionnaire changed from 56.2 ± 21.7 at baseline to 52.9 ± 21.3 (p = 0.03) after 3 weeks, to 49.3 ± 19.3 (p = 0.03) after 8 weeks, and to 46.5 ± 25.6 (p = 0.028) after 12 weeks. With respect to sexual function, mean IIEF scores were 37.2 ± 19.6 at baseline and 38.7 ± 19.2 and 40.2 ± 22.0 (p = 0.033) after 3 and 12 weeks, respectively. Serum total testosterone increased from 2.13 ± 1.20 ng/ml at baseline to 6.04 ± 3.08 ng/ml (p = 0.005) after 12 weeks, and free testosterone was marginally significantly changed from 8.60 ± 2.25 pg/ml to 11.40 ± 3.81 pg/ml (p = 0.13). However, there were no significant changes in liver function tests, red blood cell count or lipid profiles. There were no significant adverse reactions that led to the cessation of the administration of oral testosterone. Conclusion: Oral administration of testosterone undecanoate can improve symptoms of PADAM in Koreans. It may, therefore, be an appropriate treatment option with few adverse effects for PADAM patients.  相似文献   

19.
《The aging male》2013,16(2):86-93
In a single-blind, placebo-controlled study, the effects of a 3-month oral administration of 160 mg/day testosterone undecanoate (Andriol®) on the quality of life of men with testosterone deficiency were evaluated. The subjects included ten men with primary hypogonadism and 29 with andropause with sexual dysfunction as the most common problem. The changes in subjective symptoms were evaluated by the PNUH QoL scoring system and the St. Louis University Questionnaire for androgen deficiency in aging males (ADAM). Digital rectal examination (DRE) was performed and serum testosterone, prostate-specific antigen (PSA) and liver profile were monitored. Testosterone undecanoate treatment (n = 33) significantly improved sexual dysfunction and symptom scores of metabolic, cardiopulmonary, musculo-skeletal and gastrointestinal functions compared to baseline and to placebo (n = 6). ADAM score also significantly improved after 3 months of treatment. Serum testosterone was significantly increased compared to pretreatment levels only in the testosterone undecanoate group. In the placebo group, no significant changes compared to baseline were found for testosterone levels and QoL questionnaires. No abnormal findings were detected on DRE or laboratory findings in either group. Adverse events, such as gastrointestinal problems and fatigue, were mild and self-limiting. It is concluded that androgen supplement therapy with oral testosterone undecanoate (Andriol) restores the quality of life through improvement of general body functions in men with testosterone deficiency.  相似文献   

20.
《The aging male》2013,16(1):23-29
Partial androgen deficiency or the andropause in the aging male is a complex clinical and biochemical entity that needs to be analyzed at two levels of the constituent structure: the 'deep structure' should come to light with more intensive research, while the 'surface structure' holds the attention of investigators who focus on hormone measurements in the blood to help diagnose the andropause. In this study, it is recognized that bioavailable testosterone decreases progressively during the aging process. This physiological decline may be so important, or so close to castration levels, that aged men may experience numerous symptoms of hypogonadism. The assay for bioavailable testosterone was indirectly validated with a set of equations derived from our knowledge of the law of mass action at equilibrium, as proposed by Vermeulen and colleagues in 1999. With this mathematical model, we have shown that calculated free testosterone was highly correlated with bioavailable testosterone. It is therefore concluded that the evaluation of aged men's androgenicity should rely on at least one of these free testosterone assessments (bioavailable or calculated free testosterone) for the sake of reproducibility in the construction of the 'surface structure' of the andropause in the coming years.  相似文献   

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