Data from a meta-analysis and an observational study suggest testosterone therapy is not associated with cardiovascular (CV) events in men, challenging earlier research that spurred the FDA to examine the safety of the treatment.

The two studies were presented at the American College of Cardiology (ACC) Scientific Sessions 2015 in San Diego.

Pawan Patel, MD, of Regions Hospital in St. Paul, Minnesota, and colleagues conducted the meta-analysis to better understand whether testosterone therapy puts men at greater risk for CV events. The analysis involved 29 heterogeneous studies featuring 122,889 men. Recent studies indicating an association between testosterone therapy and adverse CV events were included.

Dr. Patel and colleagues found that testosterone therapy did not significantly increase the risk for CV events in men (RR=1.168; CI, 0.794-1.718; P=.431).

“With an aging population and more and more men needing testosterone therapy, it is important to better understand its potential effect on cardiovascular health,” Dr. Patel said in a press release. “Our analysis ... gives hope that we can do more with testosterone therapy.”

Arshad Jahangir, MD, Zuber Ali, MD, and colleagues from Aurora Health Care in Wisconsin, found similar results in a study involving their community-based health care system. The observational analysis included 7,245 men (mean age, 54 years) who had low testosterone levels (<300 ng/dL) between 2007 and 2013.

At 3-year follow-up, the CV event rate — a composite of acute myocardial infarction, stroke and death — was 5.5% in the treated arm and 6.7% in the untreated arm. After adjustment for age, prior myocardial infarction or stroke, cholesterol levels, smoking status and follow-up length, there was no difference in CV event rates between groups.

“The reassurance we get from this analysis in the community setting is that testosterone replacement therapy in patients with low serum levels is not causing any harm, even if it is not providing much cardiovascular benefit [in this patient population],” Dr. Jahangir said in the release.

“In the absence of prospective data, I think studies like ours will help ease anxieties around this treatment and provide some information on which physicians can base their prescribing decisions.”
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Because of these results, Dr. Jahangir said that it is critical for physicians to continue to aggressively manage established patients' CV disease risk factors, since testosterone therapy may not have an effect. He also said an analysis to determine the role of testosterone therapy on metabolic parameters and bone fractures is currently ongoing.

A new observational study of hypogonadal men may ease concerns over testosterone therapy, widely believed to fuel prostate cancer (PCa) despite a lack of evidence. Researchers found lower than expected incidences of PCa among the men, who received testosterone therapy for a median of 5 years (maximum 17 years).

“Testosterone therapy in hypogonadal men does not increase the risk of prostate cancer,” lead researcher Ahmad Haider, MD, PhD, of University Clinics Muenster in Germany, and colleagues stated in The Journal of Urology, published online ahead of print. “If guidelines for testosterone therapy are properly applied, testosterone treatment is safe in hypogonadal men.”

Hypogonadal men having surgery for localized prostate cancer can be “cautiously considered” candidates for testosterone  therapy after a year if there is no evidence of active disease, according to a set of guidelines the researchers described.

For the study, the investigators examined data for a total of 1,023 men at 3 independent centers who had hypogonadism and were receiving testosterone  therapy. Hypogonadism was diagnosed when testosterone levels were 12.1 nmol/L or less and symptoms such as loss of libido and unusual weight gain were present. Patients received injections of testosterone undecanoate  in intervals of 12 weeks.

A total of 11 patients at 2 urology centers were diagnosed with PCa; the third center reported no cases. PCa incidences were 54.4 and 30.7 cases per 10,000 patients per year, respectivelylower than would be expected in the general population. The cohorts did include some younger patients, which could have affected the results.
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In the interest of disclosure, several study authors noted a relationship with Bayer, which manufactures testosterone undecanoate.