Scientists are exploring an affordable way to fight early memory loss by studying the effects of nicotine patches for patients with mild cognitive impairment, which can be a precursor to Alzheimer's dementia.
Nicotine, a natural product of various plants including the tobacco plant, is notorious for its addictive properties in tobacco products like cigarettes. But the scientific community knows it for another quality: After years of research, the chemicals’ cognitive-enhancing traits have been well-established in laboratory settings. Now, scientists are hoping to leverage nicotine’s benefits, exploring its potential for treating early memory loss when the chemical is removed from its toxic hosts like cigarettes.
In the largest and longest scientific study of its kind, the Memory Improvement Through Nicotine Dosing (MIND) study is underway to test whether nicotine patches can improve cognitive abilities and daily functioning in nonsmokers with mild cognitive impairment, a syndrome that can be a precursor to Alzheimer’s dementia.
The clinical trial is part of a broader effort in Alzheimer’s research to study the effects of repurposed therapies, which account for nearly 40 percent of all investigational treatments in the pipeline. Developing a new drug is an onerous process, and Dr. Paul Newhouse, director of the MIND study and the Center for Cognitive Medicine at Vanderbilt University Medical Center said repurposing therapies such as nicotine patches — transdermal patches that release small doses of nicotine through the skin in order to treat nicotine addiction in tobacco consumers — could accelerate the search for effective Alzheimer’s treatments.
“We’re trying to see if we can find ways to take what’s already in our medicine cabinet and see if there are other ways to use it. Nicotine is one of those compounds,” Newhouse told Being patient.
“We don’t expect nicotine to be a home run,” he continued. “It’s not going to cure Alzheimer’s disease, but we believe that it stands a good chance of being able to help with some of the mental and cognitive difficulties of the disease, and it costs very, very little.”
According to Newhouse, nicotine has long played an important role in pharmacology research. As far back as the early 1900s, scientists used nicotine to help characterize receptors that respond to acetylcholine. The neurotransmitter passes information between neurons by binding onto various receptors, and cells that produce this chemical messenger become degraded in Alzheimer’s.
Currently, a class of FDA-approved medications for Alzheimer’s, cholinesterase inhibitors like Aricept (donepezil), block an enzyme that breaks down acetylcholine, thereby helping sustain the level of these neurotransmitters. But Newhouse noted that nicotine works via a more direct mechanism, imitating acetycholine’s function by activating nicotinic acetylcholine receptors. In fact, Newhouse said nicotine increases the level of these receptors, and it could potentially complement cholinesterase inhibitors’ effects.
Previously, a pilot study by Newhouse and colleagues showed encouraging results in treating mild cognitive impairment with nicotine patches. The small clinical trial involved 74 participants with the syndrome, all of whom were nonsmokers. After six months, patients who received nicotine patches had improved attention and memory, compared to the placebo group.
The team also found that nicotine treatment was safe and well-tolerated, and no withdrawal symptoms were reported by the participants. Furthermore, none of them reported using nicotine products after the study.
While nicotine consumption from smoking often leads to nicotine dependence, Newhouse said there isn’t any evidence from the pilot study or other studies to show that the nicotine patches are addictive: That’s likely because nicotine patches offer a more steady level of nicotine over a longer period, whereas nicotine rapidly hits the brain when it’s inhaled through tobacco products like cigarettes.
Meanwhile, the perils of smoking are well-known as it greatly increases people’s risk for health conditions including cancer and cardiovascular disease. According to the FDA, even though nicotine is the addictive substance in tobacco products, what causes serious disease and death is actually the mix of a host of chemicals, not nicotine, in tobacco and tobacco smoke. And there are various FDA-approved nicotine replacement therapies available over-the-counter, like nicotine patches, to help people quit smoking. In the case of mild cognitive impairment, nicotine patches remain as an investigational treatment as research is still underway.
“It does appear that nicotine is safe for the heart and it’s safe for the lungs when it’s given by patch,” Newhouse said, “and we want to see if it helps the brain.”
Newhouse and colleagues are currently building on the pilot clinical trial’s findings. In the ongoing MIND study, the team is studying the effects of nicotine patches for mild cognitive impairment over a two-year period, and they have recruited the majority of the study’s target enrollment of 300 people.