Image caption The patches deliver nicotine - the "addictive" chemical found in cigarettes

Nicotine patches may improve the memory of elderly people experiencing the earliest symptoms of dementia, researchers suspect.

The patches appear to give a cognitive boost to people with mild memory impairment.

The findings, published in the journal Neurology, come from a small study of 67 people over a period of six months.

Experts say the results are not conclusive, merely hinting of a benefit and do not mean people should smoke.

The health risks of smoking massively outweigh any potential nicotine benefits. And nicotine is known to be addictive.

Longer and larger studies are now needed to fully assess nicotine's effect on memory and whether it might point the way to new treatments for Alzheimer's disease and other forms of dementia, they say.

Early promise

There are some 820,000 people in the UK living with dementia. Although some drugs are already available that can lessen some of the symptoms of the disease, there is no cure for this progressive disorder.

Memory and cognition are some of the first functions that begin to fail in a person with dementia.

We do not know whether benefits persist over long periods of time and provide meaningful improvement Lead researcher Dr Paul Newhouse

They may find it difficult to recall recent events or facts or become increasingly confused, even when in familiar surroundings, for example.

Scientists have known for some time that the brain contains receptors that respond to nicotine and that a number of these are lost in Alzheimer's.

The latest work found that six months of treatment with nicotine patches appeared to improve how well individuals with "pre-dementia" or mild cognitive impairment (MCI) performed on tests designed to assess memory, attention and response times.

After six months of treatment, the nicotine-treated group regained 46% of normal performance for age on long-term memory, whereas the placebo group worsened by 26% over the same time period.

However, the findings were not statistically significant - a measure investigators need results to meet in order to rule out any chance findings.

The scientists say more studies are now needed to confirm their preliminary findings.

Lead author Dr Paul Newhouse, of Vanderbilt University School of Medicine in Nashville, said: "This study provides strong justification for further research into the use of nicotine for people with early signs of memory loss.

"We do not know whether benefits persist over long periods of time and provide meaningful improvement."

Derek Hill, professor of medical imaging science at University College London, said the study gave some exciting evidence that mild memory problems might be treatable before they develop into full blown dementia.

But he added: "Nicotine is just one of the existing or experimental drugs that could prove beneficial for this patient group. It should encourage more investment into research into possible treatments.

"It is quite likely that no treatment will help everyone - and so new diagnostic tests to match patients to treatments may be also needed to tackle dementia."