In July 2019 researchers from the UK, USA, Australia and Germany published the results of their study to assess whether a healthy lifestyle is associated with a lower risk of dementia regardless of genetic risk. A total of 196,383 individuals (average age 64 years; 53% women) with no history of cognitive impairment or dementia were included in the study and followed up for an average of 8 years. Information on smoking, physical activity, diet and alcohol consumption was analysed, and the individuals were divided into three groups, namely favourable, intermediate, and unfavourable lifestyles. Overall, 68% of participants were assessed to be following a favourable lifestyle, 24% an intermediate lifestyle, and 8% an unfavourable lifestyle. In addition, the genetic risk of dementia was analysed and 20% were assessed to have a high risk, 60% an intermediate risk and 20% a low risk of developing dementia. Information on the incidence of dementia was obtained from hospital and death records. Results showed that both an unfavourable lifestyle and a high genetic risk were independently significantly associated with a higher risk of dementia. However, a further analysis revealed that a favourable lifestyle was associated with a lower risk of dementia even in those individuals with a high genetic risk.
Lourida I et al. Association of Lifestyle and Genetic Risk With Incidence of Dementia. JAMA. 2019 Jul 14. [Epub ahead of print]