Drugs that are used for treating Alzheimer's disease in its early stages may also slash risk of heart attacks and death, a new study has claimed.
A large study of over 7,000 people with Alzheimer's disease in Sweden looked at cholinesterase inhibitors (ChEIs), such as donepezil, rivastigmine and galantamine, which are used to treat mild to moderate Alzheimer's disease.
Side-effects of ChEIs include a beneficial effect on the vagus nerve, which controls the rate at which the heart beats, and some experimental studies have suggested that ChEIs could also have anti-inflammatory properties.
Professor Peter Nordstrom, of Umea University, Umea, Sweden, and colleagues followed 7,073 people with Alzheimer's disease, who were on the Swedish Dementia Registry from May 2007 to December 2010.
They found that those who were on ChEIs had a 36 per cent reduced risk of death from any cause, a 38 per cent reduced risk of a myocardial infarction (heart attack) and a 26 per cent reduced risk of death from cardiovascular causes such as stroke compared to people not taking ChEIs.
"If you translate these reductions in risk into absolute figures, it means that for every 100,000 people with Alzheimer's disease, there would be 180 fewer heart attacks - 295 as opposed to 475 - and 1125 fewer deaths from all causes - 2000 versus 3125 - every year among those taking ChEIs compared to those not using them," Nordstrom said.
Patients taking the highest recommended doses of ChEIs had the lowest risk of heart attack or death: 65 per cent and 46 per cent lower respectively compared with those who had never used ChEIs.
The researchers also checked whether the reduction in risk applied only to the use of ChEIs or was seen in other drug treatments for dementia.
Memantine is a drug indicated for use in moderate to advanced Alzheimer's disease and works in a different way to ChEIs. The researchers found it made no difference to the risk of heart attack or death from any cause.
"As far as we know, this is the first time that the use of ChEIs has been linked to a reduced risk of heart attacks and deaths from cardiovascular disease in general or from any cause," Nordstrom said.
"As this is an observational study, we cannot say that ChEI use is causing the reduction in risk, only that it is associated with a reduction.
"However, the strengths of the associations make them very interesting from the clinical point of view, although no clinical recommendations should be made on the basis of the results from our study.
"It would be of great value if a meta-analysis of previous, randomised controlled trials could be performed, as this might produce answers on which clinical recommendations could be based," Nordstrom said.
The research was published in the European Heart Journal.
