Androgen Deprivation for Prostate Cancer Ups PAD Risk

Androgen Deprivation for Prostate Cancer Ups PAD Risk

NEW YORK (Reuters Health) Feb 15 - A population-based observational study indicates that androgen deprivation therapy for nonmetastatic prostate cancer is tied to an increased risk of venous thromboembolism (VTE) and peripheral artery disease (PAD).

"Additional research is needed to better understand the potential risks and benefits of androgen deprivation therapy (ADT), so that this treatment can be targeted to patients for whom the benefits are clearest," conclude the Boston-based authors of the report.

In their paper, published online February 1 in European Urology, Dr. Jim C. Hu at Brigham and Women's Hospital and colleagues point out that ADT is known to increase the risk of coronary artery disease and stroke, but there's little information about its effect on peripheral vascular risk.

The research team used data from the population-based SEER tumor registry linked to Medicare data to identify 182,757 men ages 65 and older with nonmetastatic prostate cancer.

"We focused on men with nonmetastatic disease, because the indication for ADT remains unclear for many men treated in this setting, and thus the risk of harm is potentially greater," the researchers explain.

Half the men received ADT, either with gonadotropin-releasing hormone agonists (47.8%) or orchiectomy (2.2%).

During a median follow-up of 5.1 years, PAD incidence rates per 1000 person years were 30.5 in the GnRH group, 27.1 in the orchiectomy group, and 21.0 without ADT. Corresponding rates of incident VTE were 13.2, 14.7 and 10.1 per 1000 person-years.

After adjustment, GnRH agonist use was associated with significantly increased risk of PAD (hazard ratio 1.16) and VTE (HR 1.10). Similarly, the hazard ratios associated with orchiectomy were 1.13 and 1.27, respectively.

The authors also found that increasing levels of comorbidity were strongly associated with these outcomes. In discussing the findings, they comment: "It is also notable that the increased risks (with ADT) were relatively modest and smaller than for the risk of increasing levels of comorbidity. This finding underscores the importance of addressing known risk factors for PAD and venous thromboembolism, especially for patients who are likely to benefit from ADT."

Reuters Health Information © 2012