[Lifestyle, genetics and the risk of dementia].

An unhealthy lifestyle increases the risk of dementia. Two observational studies explored whether targeted health and lifestyle interventions could attenuate or even offset increased genetic risk. Results from these observational studies are inconclusive. However, after the age of 60, favourable lifestyle behaviours may have less impact in groups with high genetic risk. This might inspire researchers and clinicians to determine genetic risk prior to offering preventive interventions. However, this raises important ethical concerns and practical difficulties. Lifestyle interventions should take place irrespective of genetically determined risk of dementia.