Department of Research & Evaluation News

PASADENA, Calif.  — Men who used testosterone replacement therapy to treat symptoms of androgen deficiency had a 33 percent lower risk of cardiovascular events such as heart attacks and stroke compared to those who did not receive any hormone therapy. The findings from the Kaiser Permanente study were published in JAMA Internal Medicine today.

Androgen deficiency in men is characterized by lower levels of male sex hormones, specifically testosterone, as well as symptoms that include loss of sexual desire, erectile dysfunction, breast enlargement or tenderness, hot flashes, reduced energy, irritability, and depressed mood. Similar to women, men experience a normal decline in sex hormone levels beginning in their 30s. The decline in men is gradual and occurs over a number of years. It is estimated that approximately 1 in 200 men under the age of 60 has testosterone levels below normal, but as many as 2 in 10 men over the age of 60 have low levels. Not all men with low testosterone levels have symptoms of androgen deficiency.

Symptoms related to androgen deficiency can be treated with testosterone replacement therapy given by injection, orally, or topically. Some recent studies, however, have raised concerns that testosterone replacement therapy may increase the risk for cardiovascular events such as heart attacks and strokes. Other studies report that low testosterone levels in older men are associated with increased cardiovascular risk and that testosterone replacement therapy may have cardiovascular benefits.

“Our study found no indication of an increased risk for cardiovascular events for men with androgen deficiency,” said T. Craig Cheetham, PharmD, MS, study lead author, Kaiser Permanente Southern California Department of Research & Evaluation. “Our hope is that these findings help alleviate the concerns that patients with androgen deficiency and their doctors may have had about prescribing and taking testosterone replacement therapy.”

The study evaluated 44,335 male patients at Kaiser Permanente medical centers in Northern and Southern California who had been diagnosed with androgen deficiency between January 1, 1999, and December 31, 2010. Of these, 8,808 men were treated with testosterone replacement therapy, while 35,527 were never dispensed testosterone. The men were followed for a median of 3.4 years and researchers found:

• Of the men who never received testosterone, 10.2 percent had a heart attack or stroke during the study period.
• Of those who received testosterone replacement therapy, 8.2 percent had a heart attack or stroke during the study period.

Other authors of the study include JaeJin An, BPharm, PhD, with Western University of Health Sciences; Steven J. Jacobsen, MD, PhD, with Kaiser Permanente Southern California Department of Research & Evaluation; Fang Niu, MS, with the Drug Information Service, Kaiser Permanente Southern California; and Stephen Sidney, MD, MPH, Charles P. Quesenberry, PhD, and Stephen K. Van Den Eeden, PhD, with Kaiser Permanente Northern California Division of Research.

This study was funded by a grant from the National Institutes of Health, National Institute on Aging (1 RO1 AG042921‐01).

About the Kaiser Permanente Southern California Department of Research & Evaluation

The Department of Research & Evaluation conducts high-quality, innovative research into disease etiology, prevention, treatment, and care delivery. Investigators conduct epidemiologic research, health services research, biostatistics research, and behavioral research as well as clinical trials. Major areas of study include chronic disease, infectious disease, cancer, drug safety and effectiveness, and maternal and child health. Headquartered in Pasadena, California, the department focuses on translating research to practice quickly to benefit the health and lives of Kaiser Permanente Southern California members and the general public. Visit kp.org/research.

About Kaiser Permanente

Kaiser Permanente is committed to helping shape the future of health care. We are recognized as one of America’s leading health care providers and not-for-profit health plans. Founded in 1945, Kaiser Permanente has a mission to provide high-quality, affordable health care services and to improve the health of our members and the communities we serve. We currently serve more than 11.3 million members in eight states and the District of Columbia. Care for members and patients is focused on their total health and guided by their personal physicians, specialists and team of caregivers. Our expert and caring medical teams are empowered and supported by industry-leading technology advances and tools for health promotion, disease prevention, state-of-the-art care delivery and world-class chronic disease management. Kaiser Permanente is dedicated to care innovations, clinical research, health education and the support of community health. For more information, go to: kp.org/share.