Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=198297
Story Retrieval Date: 5/23/2013 11:19:56 AM CST
Nonsmokers may one day use the nicotine patch to improve their memory, attention and reaction time, researchers at Vanderbilt University School of Medicine Nashville, Tenn., predict.
In a study of 74 patients, they found that administering 15-milligram patches once a day improved attention, memory and mental processing among elderly nonsmokers without Alzheimer’s disease.
"People with mild memory loss should not start smoking or using nicotine patches by themselves because there are harmful effects of smoking and a medication such as nicotine should only be used with a doctor's supervision," said Dr. Paul Newhouse, a researcher at Vanderbilt.
Nicotine may be a neuroprotective, meaning the stimulant shields neurons from injury or degeneration, he said. It may also have a role in preventing a toxic protein “thought by many to be responsible for initiating the Alzheimer cascade and memory loss,” he said.
Sixty-seven subjects completed the trial: 34 with nicotine patches and 33 receiving placebos. On the path toward mild cognitive impairment due to normal aging and mild dementia, the participants--who were in their seventies and above--were neither smokers nor diagnosed with Alzheimer’s disease.
At the end of six months, attention improvement and cognitive tests as well as patient and observer ratings showed patch users regained 46 percent of long-term memory performance when compared to others their age. The controlled group worsened by 26 percent. Tests included a paragraph and word recall task.
Researchers offered all patients who completed the study an additional six months with the patch to see if the positive effects persisted. These results have not been reported,
Newhouse said he submitted a proposal to the National Institute on Aging to begin a study with a larger sample size and longer duration. The potential clinical trial will look even earlier along the road towards mild cognitive impairment.
People with a gene that puts them at a higher risk of Alzheimer’s disease responded better than others on some tests, Newhouse said. Yet the positive results could be an artifact, meaning since their symptoms were more severe, there was more room for improvement.
Extensive clinical trials on the effectiveness of nicotine to improve mental processes and potentially to forestall Alzheimer’s is needed, said Dr. Marsel Mesulam, director of the Cognitive Neurology and Alzheimer’s Disease Center at Northwestern University.
“Theoretically we know that patients with Alzheimer’s disease have decreased nicotine receptors in main parts of the brain, so conceivably doing something that increases nicotine transmission in the brain might have some effect on their cognitive state,” the neurology professor said.
Stimulating nicotine receptors makes can make nerve cells more active, but “not everything that makes nerve cells work harder is better,” he said. Even though attention and memory could be improved in Alzheimer’s cases, fewer functioning receptors exist, so the effect of stimulating them is a little difficult to predict.
One patient left the study once the highest dosage was administered because of adverse effects. Other side effects included an average weight loss of nearly six pounds.
“I wouldn’t recommend using nicotine for the purpose of thinking or remembering until I can take a look at the methodology,” Mesulam said.
Peggy Dunbar, a 62-year-old retired banker, has an 82-year-old mother with moderate-stage Alzheimer’s disease. Her mother trusts her with all health-related decisions.
“I tried the nicotine patch once and it made me sick. I wouldn’t want to do that [to her],” she said.
Louise Daugherty, her mother, is taking donepezil, a pill that may help slow cognitive impairment. There is no cure for Alzheimer’s disease.
“At her age, we’re just going to do this and be done with that,” Dunbar said.