Men with prostate cancer are often treated with hormone therapy (androgen deprivation therapy [ADT]), but this treatment can have unpleasant and even harmful side effects, including metabolic abnormalities that lead to diabetes mellitus (DM) and cardiovascular disease (CVD). A new study found that with prolonged exposure to ADT (2 years), both DM and CVD are more likely to occur in older men and in men with comorbidities than in younger men.
This study should reassure younger men diagnosed with prostate cancer who are prescribed ADT, said lead author Alicia K. Morgans, MD, of the Vanderbilt University School of Medicine, Nashville, Tennessee. However, older men with comorbidities who have a higher risk may want to select a different treatment option, she added.
The study assessed the association between duration of exposure to ADT and development of incident DM or CVD in a prospectively surveyed cohort of 3718 survivors diagnosed with local prostate cancer and enrolled in the Prostate Cancer Outcomes Study at 6 SEER sites. Of these survivors, 3526 were eligible for the study: 2985 for the DM analysis and 3112 for the CVD analysis.
Patients were stratified by length of exposure to ADT: no ADT (2033 in the DM analysis and 2112 in the CVD analysis); ADT for <2 years (692 in the DM analysis and 723 in the CVD analysis); or ADT for 2 years (260 in the DM analysis and 277 in the CVD analysis). Development of DM or CVD was established by patient report in surveys at baseline, 6 months, and 1-, 2-, 5-, and 15-year time points as well as by death certificate diagnoses.
Older men (>76 years for DM and >74 years for CVD) who were exposed to ADT for 2 years had the highest risk of developing DM and CVD. A multivariate analysis identified greater comorbidity burden as being significantly associated with odds of developing DM or CVD versus men with no other comorbidities.
Shorter exposure to ADT (<2 years) was not significantly associated with developing either DM or CVD over 15 years of follow-up.
The main implication of these findings is that older men with comorbidities who have been taking ADT for 2 years should be monitored for DM and CVD, Morgans said.
Morgans AK, Fan K-H, Koyama T, et al. Influence of age on incident diabetes (DM) and cardiovascular disease (CVD) among prostate cancer survivors receiving androgen deprivation therapy (ADT). J Clin Oncol. 2014;32(suppl 4):Abstract 31. Presented at: 2014 Genitourinary Cancers Symposium; January 30-February 1, 2014; San Francisco, CA.