Monitoring testosterone replacement therapy with transdermal gel: when and how?

The HEAT-Registry (HEmatopoietic Affection by Testosterone): comparison of a transdermal gel vs long-acting intramuscular testosterone undecanoate in hypogonadal men

CONTEXT

Testosterone (T) therapy of hypogonadal men requires stable kinetics, tolerance and attenuation of symptoms. Both intramuscular injections of the long-acting ester T undecanoate (TU) and transdermal application of T gel offer a proven efficacy. As T has marked effects on hematopoiesis, an elevation of hematocrit has to be considered during T therapy.

OBJECTIVE

To compare the effects of a transdermal T gel with long-acting intramuscular TU on hematopoiesis, controlling for age, diagnosis, androgen receptor susceptibility and obesity.

DESIGN

Prospective two-arm open registry, minimum duration of 26 weeks per patient. Putative modulators of erythropoiesis entering regression models were type of medication, type of hypogonadism, delta of total testosterone concentrations, waist circumference, age as well as (in a sub-group) androgen receptor gene CAG repeat length.

SETTING

Tertiary university based andrological outpatient department.

PATIENTS

802 hypogonadal men, 498 receiving T gel and 304 receiving intramuscular TU, median age 40 years (interquartile range = 25).

RESULTS

Follow-up visits after initiation of treatment occurred between treatment weeks 26-30. Serum T concentrations increased markedly in both patient groups. Men receiving intramuscular TU exhibited an increased hematocrit (>50%) to a significantly higher amount than men receiving T gel (69/304 vs. 25/498, p < 0.001). Corresponding results were seen for higher values of hematocrit (>52% and >54%). Advanced age (p = 0.009), higher waist circumference (p = 0.01), higher delta testosterone (p = 0.007) and functional vs classical hypogonadism (p = 0.04) contributed to the effect in stepwise multiple regression models. Attenuated androgen action (longer androgen receptor CAG repeats) mitigated the effect (p = 0.01) in a subgroup of 574 patients. Men with anemia (hemoglobin ≤12.7 g/dl) were more likely to move out of the pathological range when receiving TU vs T gel (41/53 vs. 49/89 p = 0.01).

CONCLUSIONS

T substitution with intramuscular TU or T gel increase T concentrations effectively. Long-acting TU leads to a higher rate of hematocrit levels >50%, whilst at the same time it seems to be more efficient to ameliorate anemia in the subgroup of respectively affected hypogonadal patients . This applies especially to obese older men with functional hypogonadism.

Hypogonadism in men: Updates and treatments

ABSTRACT

Hypogonadism is a clinical syndrome of testosterone deficiency that presents with nonspecific symptoms of sexual dysfunction, fatigue, and decreased strength or muscle mass. Men with obesity, diabetes, and other comorbidities are at higher risk for hypogonadism. Patients presenting with symptoms should be tested for low testosterone and treated with testosterone replacement. Testosterone therapy carries risks and must be closely monitored. Patients treated for hypogonadism may experience improvement of symptoms and quality of life.

Pharmacokinetics of testosterone therapies in relation to diurnal variation of serum testosterone levels as men age

Background

To improve symptoms associated with testosterone deficiency, many testosterone therapies are available that aim to restore serum testosterone (T) levels to the normal physiologic range. The magnitude, frequency, and duration between peak and trough T concentrations vary with route of administration, and none reflect normal endogenous daily diurnal T variations.

Objective

To compare pharmacokinetic profiles of serum T from approved T formulations with endogenous diurnal T variations in young and older men, and to consider whether there may be value in mimicking the diurnal T rhythmicity with exogenous testosterone therapies as men age.

Materials and methods

A literature search of studies examining the diurnal variation of endogenous T in healthy men and men with testosterone deficiency was performed using PubMed in January 2020. Additional searches for serum T pharmacokinetic profiles of various testosterone therapy formulations were also conducted. Prescribing information for various T formulations was also reviewed.

Discussion and conclusion

Endogenous diurnal T variation is well described and appears to be blunted naturally as men age. Men with testosterone deficiency lack diurnal T variation and exhibit a flatter T profile compared with eugonadal men. Some T replacement options provide intraday T level variations similar to normal circadian secretion, and others provide a flatter exposure profile reflective of depot release. Others provide profiles that exceed the frequency and physiologic range of the natural diurnal variation of T. All exogenous T replacement dosing targets an increase in average T levels to within the normal physiologic range and improves symptoms associated with low T, but no single testosterone therapy can exactly mimic the normal diurnal T patterns seen in younger men and the blunted circadian T secretion of older men.

Evaluation of the Efficacy of Transdermal and Injection Testosterone Therapy in Klinefelter Syndrome: A Real-Life Study

Context

Klinefelter Syndrome (KS) is the most frequent sex chromosome disorder in males. Due to hypergonadotropic hypogonadism, treatment with testosterone replacement therapy (TRT) is commonly indicated. There are no international guidelines for the most appropriate TRT in KS.

Objective

We aimed to evaluate how different routes of testosterone administration impact testosterone-responsive variables, as well as the development of later metabolic diseases and other complications.

Methods

We conducted a retrospective study covering 5 years from 2015 to 2020. Data on TRT, biochemical parameters, bone mineral density (BMD), medications, comorbidity, and karyotyping were derived from electronic patient records and The Danish Cytogenetic Register.

Results

A total of 147 KS males were included: 81 received injection TRT, 61 received transdermal TRT, and 5 did not receive TRT. Testosterone levels were similar in the 2 TRT groups (P = 0.9), while luteinizing hormone and follicle-stimulating hormone levels were higher in the group receiving transdermal TRT (P = 0.002). Levels of cholesterol, blood glucose, hemoglobin A1c, hemoglobin, hematocrit, liver parameters, prostate-specific antigen, and spine and hip BMD were similar in the 2 treatment groups (Ps > 0.05).

Conclusion

TRT, irrespective of route of administration, affects androgen-responsive variables similarly in males with KS. Neither long-acting injection nor transdermal gel seem to reduce the risk of metabolic diseases significantly. These results should encourage clinicians in seeking the route of administration resulting in the highest degree of adhesion to treatment based on individual patient preferences. Implementation of shared decision-making with patients may be important when choosing TRT.

Reliability of a dried urine test for comprehensive assessment of urine hormones and metabolites

Background

Mass spectrometry allows for analysis of multiple hormone and organic acid metabolites from small urine volumes; however, to assess the full extent of daily hormone production, 24-h urine collections are usually required. The aims of this study were, first, to confirm that mass spectrometric analysis of an array of hormones and organic acids would yield similar results in both liquid and dried urine, and, second, to determine if collection of four dried spot urine samples could be substituted for a 24-h collection when measuring reproductive hormones.

Methods

Two study populations were included in this prospective observational study. Twenty individuals collected both a spot liquid urine and dried urine on filter paper to analyze eight organic acids. A second group of 26 individuals collected both a 24-h urine and four dried spot urines during waking hours throughout the same day for evaluation of 17 reproductive hormones and metabolites; data from 18 of these individuals were available to compare liquid versus dried urine results. Dried urine was extracted, hydrolyzed, and derivatized before analysis by mass spectrometry; all analytes from dried urine were normalized to urine creatinine.

Results

Reproductive hormone results from dried and liquid urine were in excellent agreement with intraclass correlation coefficients (ICCs) greater than 0.90; comparison of dried to liquid urine for organic acids showed good to excellent agreement (ICC range: 0.75 to 0.99). Comparison between the 4-spot urine collection and 24-h urine collection methods showed excellent agreement (ICC > 0.9) for 14 of the 17 urine metabolites and good agreement for the others (ICC 0.78 to 0.85) with no systematic differences between the two methods of collection.

Conclusions

The burden of urine collection can be reduced using collection of four spot dried urines on filter paper without compromising comparability with hormone results from a 24-h urine collection. A large number of urine analytes can be assessed from the dried urine with similar results to those from liquid urine. Given the ease of sample handling, this 4-spot dried urine assay would be useful for both clinical assessment of patients and for large epidemiologic studies.

Supplementary information

The online version contains supplementary material available at 10.1186/s13065-021-00744-3.