A new review of past clinical trials confirmed what many doctors already suspected: Three drugs that treat Alzheimer's disease -- Aricept, Razadyne and Exelon -- provide only a small benefit to patients.
The review, published in this month's issue of The Cochrane Library, evaluated 13 high-quality studies involving more than 7,000 patients. All three drugs made equally small improvements in the patients' mental functioning and in their ability to carry out everyday activities.
The results of this review confirm what past studies have shown -- that the drugs have a modest effect. However, doctors' opinions vary about the usefulness of the drugs. Some said they believe the drugs help patients while other doctors believe they bring little benefit.
Dr. William Pendlebury said that small improvements are still important.
"It is important, regarding the word 'improvement,' to consider what that means in the context of a disorder like Alzheimer's disease," said Pendlebury, medical director at the Memory Center at the University of Vermont College of Medicine. "Achieving stability or slowing disease progression is regarded as improvement in a disease in which the natural history is a progressive, downhill course."
Dr. Thomas Finucane, medical professor at Johns Hopkins University School of Medicine, cautioned that the benefits of the expensive medications are too modest for patients to notice a difference.
"The vast majority ... of patients and caregivers cannot tell whether they are taking these drugs or are taking placebo," said Finucane.
The conflicting opinions mean that it's up to patients and their doctors to decide what to do, said Dr. Zaven Khachaturian, editor in chief of Alzheimer's and Dementia: Journal of the Alzheimer's Association.
"Any family members find even six months of modest symptomatic relief a better choice than no treatment," Khachaturian said.
Relief, however, also means no significant side effects -- but in the Cochrane Library's review, side effects were responsible for about 29 percent of the patients leaving the studies.
"These medications are not worth side effects if it means the patients' quality of life suffers as a consequence. The purpose of these drugs is not to save lives but to save lifestyles," said Dr. Yuval Zabar, a neurologist at the Lahey Clinic in Massachusetts.
Dr. Rajesh V. Swaminathan is a medical resident at Massachusetts General Hospital.