Study Urges Monitoring Cognitive Function in ADT Patients

Men receiving androgen-deprivation therapy (ADT) for prostate cancer have long complained about vague changes in cognition. A recent study found “subtle but significant” cognitive declines in men undergoing ADT.

“Oncologists often hear their patients complain about not being able to think as fast as they used to,” says Christian Nelson, PhD, a psychologist in the Department of Psychiatry and Behavioral Sciences at the Memorial Sloan-Kettering Cancer Center in New York City. “At the same time, literature was coming out about ‘chemo brain.’ Between the two, more focus is being put on cancer therapies and cognitive functioning.”

A literature search found several studies that investigated possible links between hormonal therapy and cognition. Between 47% and 69% of men on ADT declined in at least one cognitive area, most commonly in visuospatial abilities and executive functioning.

“We found hormone therapy for some men may result in subtle effects in the ability to do more than one thing at a time,” says Nelson. “It is important to note that these are not dramatic changes and may be hard to see.”

J. Brantley Thrasher, MD, is chair of the Department of Urology at the University of Kansas Medical Center in Kansas City. He notes that this study is new in the sense that it attempts to put together the available literature. The problem is that there is no standard way of measuring cognitive function, which limits the ability to make comparisons.

“Cognition is such a complex thing, especially in the elderly,” he says. “The average age of diagnosis in prostate cancer is in the 60s with many [patients] being in their 70s or even 80s by the time they progress to hormonal therapy. You already have some kind of cognitive impairment in many of these patients, making the real question: what is baseline, and what is caused by the ADT.”

Another confounder, especially at the community level, is a kind of placebo effect. Thrasher notes that the moment a physician mentions a subjective side effect—like a change in cognitive functioning—some patients will immediately begin to endorse these symptoms.

“No question, we are noticing more and more potential complications associated with knocking out male hormones in elderly men,” Thrasher says. “These are not innocuous drugs, but medications with very serious, long-term side effects that we need to keep in mind and discuss with the patient. This is yet another indication of the wide-ranging types of concerns that patients and doctors need to think about.”

Nelson stresses that the research is not yet to the point where any intervention guidance can be given. He also feels that it is important that these possible changes be discussed with the patient often. “Monitor the patient by asking how they are doing and listening closely for their response,” says Nelson. “When the patient says things like they can’t seem to remember things, don’t feel as sharp as they used to, or not thinking as fast as they used to, then further assessment may be warranted.”

If the cognitive effects do appear, Dr. Nelson has some suggestions on easily accomplished interventions based on the specific complaint. For example, if the patient is concerned about memory loss, have him carry around a pen and small pad of paper to write down things that need to be recalled. If executive function is impacted, completing one task before going on to the next may be helpful as would planning the day more completely.

“We are in the beginning stages of understanding the cognitive effects of ADT,” says Nelson. “As we learn more, we should begin to get better answers to the questions we have about recognition and intervention.”