Observational studies have suggested that statin use is associated with a lower risk of Alzheimer's disease (AD) but prospective studies have proved inconclusive. The Rotterdam Study - a prospective cohort study involving 6992 people in The Netherlands - now suggests the effect is real (J Neurol Neurosurg Psychiatry 2009;80:13-7).
 

Over an average follow-up of nine years, 739 people in the cohort developed dementia; of these, 582 were diagnosed with probable AD. Using data on dispensed prescriptions and after adjustment for confounding factors, use of statins was associated with a 43 per cent lower risk of AD compared with no use. There was no difference between lipophilic (eg simvastatin) and hydrophilic (eg pravastatin) statins (though numbers in these subgroups were small). This effect was not modified by the ApoE4 genotype. By contrast, non-statin lipid-lowering drugs such as fibrates were not associated with a lower risk.