People who have a history of gout are 24% less likely to develop Alzheimer's disease during their lifetime, a study has revealed.
Researchers from the Division of Rheumatology, Allergy, and Immunology at Massachusetts General Hospital, and at Boston University Medical Center analysed data from The Health Improvement Network (THIN) from 1995 to the end of 2013.
Gout is medical condition usually characterised by recurrent attacks of acute inflammatory arthritis. It is caused by elevated levels of uric acid in the blood. The uric acid crystallises, and the crystals deposit in joints, tendons and surrounding tissues.
The researchers were attempting to prove - or disprove - the theory that uric acid can also help protect one from the degenerative brain disease.
In addition to building up around the joints as a waste product, uric acid may also function as an antioxidant which helps to protect the body against cell damage, research has indicated.
Gout used to known as the "rich man's disease"; King Henry VIII famously suffered from it. It is associated with eating too much rich food, wine and beer, but today it can just as well be linked to impoverished people on poor diets, and it is on the increase.
Recent research revealed that the condition is becoming more common in the UK, affecting around one in every 40 people. Men are much more likely to be affected.
After analysing data of over 3.7 million patients aged older than 40, the researchers concluded that those who have suffered from gout are a quarter less likely to develop Alzheimer's.
Overall, the researchers identified 309 new cases of Alzheimer's disease among 59,224 patients with gout. In the comparison group over a five-year follow-up period, they found 1,942 cases of Alzheimer's among 238,805 patients.
The study's authors wrote in the Annals of the Rheumatic Diseases: "Our findings provide the first population-based evidence for the potential protective effect of gout on the risk of Alzheimer's disease and support the purported neuroprotective role of uric acid.
"If confirmed by future studies, a therapeutic investigation that has been employed to prevent progression of Parkinson's disease may be warranted for this relatively common and devastating condition."