Read Original Release

Observational study on testosterone replacement therapy for COPD doesn’t prove cause and effect


2 Star

Testosterone replacement therapy may slow the progression of COPD

Our Review Summary

This release summarizes an observational study noting a relationship with two groups of men (middle aged and older), their consumption of testosterone replacement therapy and whether they are hospitalized for respiratory problems. It found that testosterone replacement therapy users had a decrease in respiratory hospitalizations compared with non-users.  While observational studies such as these are useful and hypothesis generating, they do not have the strength of a randomized, blinded trial and hence one cannot conclude that such associations are causal.  Better information about the harms, costs and conflicts of interests of the researchers would have made this a better news release.


Why This Matters

If testosterone replacement therapy (TRT) slows the progression of COPD in men by producing a positive lung function, this could indeed be a public health advance.  Observational studies, however, are problematic in that the two cohorts of men observed (those who take TRT and those who don’t) may be different in other fundamental ways.  There could, for example, be a “healthy user bias” in that the TRT cohort of men may be naturally healthier at the start, and that any improvements in COPD function may just be a function of their basic overall health. Studies like these allow us to draw conclusions, but only that there is an association — not that TRT caused a reduction in COPD.


Does the news release adequately discuss the costs of the intervention?

Not Satisfactory

There was no discussion of costs.

Does the news release adequately quantify the benefits of the treatment/test/product/procedure?

Not Satisfactory

The benefits were reported in quantitative terms:  “middle-aged testosterone replacement therapy users had a 4.2 percent greater decrease in respiratory hospitalizations compared with non-users and older testosterone replacement therapy users had a 9.1 percent greater decrease in respiratory hospitalizations compared with non-users.”  Even though this suggests that testosterone replacement therapy may slow the progression of disease in men with COPD, one is still left wondering how often that occurs. We aren’t given any baseline numbers so the 4.2% and the 9.1% relative risk numbers lack context.

Does the news release adequately explain/quantify the harms of the intervention?

Not Satisfactory

There are known dangers to TRT including raising the risk of prostate cancer but none of the risks are mentioned in the news release.

Does the news release seem to grasp the quality of the evidence?

Not Satisfactory

We are told that the study is based on a database of “450 men aged 40 to 63 with COPD who began testosterone replacement therapy between 2005 and 2014,” as well as “253 men with COPD aged 66 and older who initiated testosterone replacement therapy between 2008 and 2013.” It is hard to say whether the size of these study groups are large enough to draw conclusions.

As the published study pointed out, the research had several limitations, none of which are pointed out in the news release:

The results of our study may have been influenced by several limitations. First, all diagnoses were based on ICD-9-CM codes, which may be inaccurate or incomplete. It is possible that some of the cases we identified may have been based on misclassified data. Second, the pharmacy plans used by both study cohorts did not cover over-the-counter medications. Our database, therefore, did not include information on coadministration of these drugs; some of them, such as n-acetylcysteine, may influence the risk of respiratory outcomes. Third, the claims data used in this study did not permit examination of certain potential confounding factors such as diet, alcohol use, and other health-related behaviors. Fourth, our study cohorts were relatively small and may have lacked adequate statistical power and precision. Finally, our data included the date the prescription was filled but not the date it was obtained by the patient. In view of this, some of the drug exposure periods may have been misclassified.

Does the news release commit disease-mongering?


There is no disease mongering here. The release provides context on how many people could be affected globally by COPD.

Does the news release identify funding sources & disclose conflicts of interest?

Not Satisfactory

The funders of the study are not named in the release. The lead author, we learn in the full paper, “has received payment, for consulting, from AbbVie, Endo Pharmaceuticals, GlaxoSmithKline Pharmaceuticals, and Auxilium Pharmaceuticals.” Some of these companies manufacture testosterone replacement therapy.  This was not mentioned in the news release.

Does the news release compare the new approach with existing alternatives?

Not Satisfactory

There are a range of treatments for COPD, none of which are mentioned in this release.

Does the news release establish the availability of the treatment/test/product/procedure?


It is pretty obvious that TRT is available to men, so the fact it wasn’t mentioned as available is a moot point.

Does the news release establish the true novelty of the approach?


The release notes that there are some previous hypothetical links between TRT and lung function in men and that this is the first “large scale nationally representative study on this association.”

Does the news release include unjustifiable, sensational language, including in the quotes of researchers?


There are no examples of egregious and unjustified language here.

Total Score: 4 of 10 Satisfactory


Please note, comments are no longer published through this website. All previously made comments are still archived and available for viewing through select posts.