A large study by scientists in the U.S. has revealed that the long-term use of ibuprofen may reduce the risk of a person developing Alzheimer's disease.
The researchers from Boston University School of Medicine looked at data on 249,000 veterans which showed those who used the painkiller for more than five years were more than 40% less likely to develop Alzheimer's.
The five years of data from the U.S. Veterans Affairs health care system included information on 49,300 people over the age of 55 years who had developed Alzheimer's disease and almost 200,000 controls.
The researchers say that some other similar painkillers may also have a protective effect but experts warn against taking ibuprofen to reduce the dementia risk.
An association between non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, and Alzheimer's disease has been reported before but studies have often produced conflicting results and the Boston researchers suggest this was because different NSAIDs have different effects.
The researchers found the use of NSAIDs over five years was associated with a 24% reduced risk of developing Alzheimer's but it was ibuprofen which had the most profound effects; other NSAIDs, such as celecoxib, had no effect.
Dr. Steven Vlad the lead author, says ibuprofen was shown in animal models and the laboratory to reduce levels of protein deposits associated with Alzheimer's in the brain and not all NSAIDs behave the same way in terms of Alzheimer's disease.
Dr. Vlad suggests the results are partly due to direct effects of the drug and because ibuprofen is the most commonly used NSAID.
He says all NSAIDs have well known side-effects which can be very serious and trials are needed to ensure the risks and benefits are very clear.
Risks include ulcers, gastrointestinal bleeding, kidney dysfunction, elevated blood pressure and in the case of COX-II inhibitors such as Vioxx, a cardiovascular risk.
Research has linked Alzheimer's disease with inflammation, and researchers believe that anti-inflammatory drugs might help delay the onset of the disease.
Other research has apparently discovered that people with shorter arms and legs may be at a higher risk for developing dementia later in life with poor nutrition in early life likely to be the link between the two.
Alzheimer's disease is the most common form of dementia and initially begins with mild memory loss and confusion, but over time escalates into complete memory loss and an inability to care for oneself; there is no cure and few effective treatments.
The study appears in the journal Neurology.