MedicalResearch.com Interview with:
Jennifer R. Rider, ScD, MPH
Assistant Professor of Medicine
Channing Division of Network Medicine
Brigham and Women’s Hospital and Harvard Medical School
Department of Epidemiology
Harvard T.H. Chan School of Public Health
Boston, MA 02115
Medical Research: What is the background for this study? What are the main findings?
Dr. Rider: Numerous studies have investigated the potential role of sexual activity on the development of prostate cancer. However, most of these studies have been small and retrospective, making them more prone to bias. In addition, previous studies often relied on proxies of exposure for sexual activity (number of sexual partners, age at first marriage, etc.), which may not adequately measure the aspects of sexual activity that are most important for prostate health. The current study is the largest prospective study to date on ejaculation frequency and prostate cancer. It includes 18 years of follow up of almost 32,000 healthy men, 3839 of whom later were diagnosed with prostate cancer. We asked men about their average monthly frequency of ejaculation between the ages of 20-29, 40-49, and in the year prior to the questionnaire (1991). We find that frequency of ejaculation throughout life course is inversely associated with risk of prostate cancer at all three of these time points. For instance, men who have an average monthly ejaculation frequency of 21 or more times/moth at ages 40-49 have a statistically significant 22% reduction in risk of developing prostate cancer compared to men with a frequency of 4-7 times/month, adjusting for multiple dietary and lifestyle factors, and prostate cancer screening history.
Medical Research: What should clinicians and patients take away from your report?
Dr. Rider: While these data are the most compelling to date on the potential benefit of ejaculation on prostate cancer development, they are observational data and should be interpreted somewhat cautiously. At the same time, given the lack of modifiable risk factors for prostate cancer, the results of this study are particularly encouraging.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Rider: The next step will be relate ejaculation to specific changes in the prostate that could impact prostate cancer development to clarify the underlying mechanism.
Ejaculation frequency and risk of prostate cancer: updated results from the Health Professionals Follow-up Study
Jennifer Rider*, Kathryn Wilson, Rachel Kelly, Erika Ebot, Edward Giovannucci, Lorelei Mucci, Boston, MA
Funding: Prostate Cancer Foundation Young Investigator Award
MedicalResearch.com Interview with: Jennifer R. Rider, ScD, MPH (2015). Frequent Ejaculation Linked To Lower Prostate Cancer Risk