Nicotine patches don't apparently work for their intended purpose, which is to help smokers butt out permanently. But they may give a memory boost to people suffering from early stages of Alzheimer's disease. Those are the conclusions of two separate studies that explored different aspects of nicotine replacement therapy.
In one study, Harvard and University of Massachusetts researchers recruited 787 adults who had recently quit smoking. At the outset, the participants were asked what, if any, aids they had used to help them kick the habit, including nicotine replacement therapy (such as patches, gum and inhalers), got advice from a doctor, or joined a smoking-cessation program. The researchers then followed the subjects over a period of five years to see who resumed smoking.
The findings, published in the journal Tobacco Control, revealed that one-third of those who quit eventually succumbed to their old vice. What's more, there was no significant difference in the relapse rate among people who used nicotine replacement therapies (NRT) and those who didn't.
"This study shows that NRT is no more effective in helping people stop smoking cigarettes in the long-term than trying to quit on one's own," said the lead author, Hillel Alpert, a research scientist at the Harvard School of Public Health.
He noted that nicotine is indeed a key addictive ingredient in cigarettes. But, unfortunately, the urge to keep smoking comes from more than just a nicotine craving. A lot of psycho-social factors must be overcome to beat the habit once and for all, he added.
In the second study, the nicotine patch produced far better results – although the researchers used the product in a rather unorthodox way.
The trial involved 74 people who had mild cognitive impairment, which is the stage between normal aging and dementia when people have mild memory or thinking problems but no significant disability.
The researchers, led by Paul Newhouse of Vanderbilt University School of Medicine in Nashville, treated half the subjects with nicotine patches, while the other half was given placebos.
After six months of treatment, the nicotine group regained 46 per cent of normal performance for their age on long-term memory tests, while the placebo group actually got worse by 26 per cent, according to the results published in the journal Neurology.
Dr. Newhouse said previous studies have suggested nicotine stimulates brain receptors, which play a role in memory and thinking: "So what we are trying to do is help that system work a little more effectively by providing [extra]stimulus with this drug."
Still, he acknowledged, "we do not know whether benefits persist over long periods of time and provide meaningful improvement." But he hopes additional research will show that "this could be one part of a comprehensive treatment approach" for Alzheimer's disease.
Although nicotine patches may have a new future as a memory aid, Dr. Newhouse isn't surprised they don't seem to help current smokers. In recent decades, he noted, smoking rates have plummeted. "People who could easily stop smoking have already done so. And what you have left is the most treatment-resistant group."