Abstracts from the 2016 AUA Convention

[Jinzang]

The American Urological Association recently held their annual meeting in San Diego. I went looking through the abstracts on their website and found three that were interesting. Here are the conclusion sections from the abstracts.

Twice Per Week Dosing of Intramuscular Testosterone (T) is Associated with Greater Risk of Erythrocytosis

Although the rate of erythrocytosis is comparable among BIW and QW dosing, more frequent dosing of injectable T is associated with a higher maximum HCT and a higher incidence of erythrocytosis. These data suggest that dosing frequency, rather than total T dose, is an important factor in development of erythrocytosis in men on injectable TRT.

Effects of tadalafil once daily in the treatment of premature ejaculation

We think that tadalafil 5 mg. once daily is safe and effective in the treatment of premature ejaculation.

Rates of Mortality Are Higher Among Professional Male Bodybuilders

Mortality rates of bodybuilders within the cohort were 34% higher than those in an age-matched general U.S. male population. The cause of this increased mortality is currently unclear, but supports the possibility that the use of performance enhancing drugs and the unique competitive training (e.g. extreme weight changes) may contribute to deaths among younger professional bodybuilders. Current work is focused on determining cause of death by linkage to the National Death Index.

Sorry, no link, the forum software won't allow it. But the site is easy enough to find with a search engine.

 

[Nelson Vergel]

You have gained a lot of brownie points for this post. Thanks

 

[Sean Mosher]

I was under the impression that lowering the T dose and injecting twice a week would reduce the risk of high hematocrit or polycythemia..........so is that not the case?

 

[Jinzang]

The abstract says:

A sample of 55 men using injectable T (cypionate or enanthate) for symptomatic hypogonadism at a single dose and frequency was selected for analysis from a single center mens health database. Age, T dosage, frequency of administration, duration of T therapy, and Hct were extracted through retrospective chart review. The cohorts were separated into 27 men on 200mg of T once weekly (QW) and 28 men on 80-160mg of T twice weekly (BIW). Indication for BIW dosing was a return of hypogonadal symptoms prior to the administration of the next dose. The maximum HCT was identified for each individual and the cohort mean of the maxima was calculated. The difference in numerical variables was assessed via Mann-Whitney U analysis.

No significant difference was identified between the mean (range) age of the QW and BIW cohorts (43.2 (27-63) years vs. 40.6 (27-62) years), respectively (p=0.36). Erythrocytosis occurred in 11% of the QW cohort with a maximum HCT (Interquartile Range) of 49.2 % (43.4, 54.6). In contrast, a maximum HCT of 51.4 % (45.7, 56.9) was observed in the BIW cohort, with 29% of men developing erythrocytosis. Statistical significance was identified in comparing the percent erythrocytosis of the two cohorts (p=0.007). The rate of erythrocytosis, defined as the number of days until maximum HCT while on testosterone, was comparable in both groups (p=0.18).

 

[PAUL-E]

I was under the impression that lowering the T dose and injecting twice a week would reduce the risk of high hematocrit or polycythemia..........so is that not the case?

I was under the same impression

 

[HarryCat]

Pure speculation on my part but it sounds like the stimulation of red blood cell production by testosterone has an upper bound. In other words red blood cell production increases linearly with T level until some maximum is reached and then it can't go up any more. So the higher peaks of the QW cohort don't directly translate into higher red blood cell production throughout the week. Then with the lower T level valley before the next injection RBC production is reduced.

On BIW injections the T level has lower peaks and valleys so it may stay in the optimum range for RBC production.

 

[maxadvance]

Pure speculation on my part but it sounds like the stimulation of red blood cell production by testosterone has an upper bound. In other words red blood cell production increases linearly with T level until some maximum is reached and then it can't go up any more. So the higher peaks of the QW cohort don't directly translate into higher red blood cell production throughout the week. Then with the lower T level valley before the next injection RBC production is reduced.

On BIW injections the T level has lower peaks and valleys so it may stay in the optimum range for RBC production.

I agree, that was pure speculation. RBC doesn't fluctuate like T levels do, if that were the case I could expect my Hematocrit to drop a few points by skipping a dose, it doesn't, I tried. This finding is very interesting.

 

[HarryCat]

I agree, that was pure speculation. RBC doesn't fluctuate like T levels do, if that were the case I could expect my Hematocrit to drop a few points by skipping a dose, it doesn't, I tried. This finding is very interesting.

I wouldn't expect there to be noticeable variation on a weekly basis, but the cumulative effect over several weeks could be significant.