All this research reinforces the results of small studies on humans by Edward Levin at Duke University's Medical Center laboratory, which found that using nicotine patches on people with Alzheimer's reduced some of their mistakes by 10 to 80 per cent.

Despite the encouraging data, some researchers are concerned that the public might misinterpret the results. In particular, they fear that some will conclude smoking is beneficial.

"By no means am I encouraging anyone to take up smoking or to continue smoking because clearly the adverse consequences of smoking outweigh any cognitive improvement," Prof. Levin said.

[...]

"It's really heart-rending when you get a call from someone who wants to know whether to use the patch, and you have to say [that] in a couple of years we will have a better answer for you," Dr. Levin said. "It's especially hard when they say, 'But my grandmother has Alzheimer's now.'"