Background
Identifying effective dementia prevention strategies is an important public health priority, given the enormous and growing societal cost of this condition. Consumption of a Mediterranean diet (MedDiet) has been proposed to reduce the risk of dementia. However, current evidence is inconclusive and is generally derived from small cohorts with limited cases of dementia. Furthermore, few studies have explored the interaction between diet and genetic risk of dementia.
Methods
We used Cox proportional hazards regression models to explore the associations between MedDiet adherence, defined by two different scores (continuous scores from the Mediterranean Diet Adherence Screener [MEDAS] and Mediterranean diet Pyramid [PYRAMID]), and the risk of dementia. all causes incident in 60,298 UK Biobank participants, followed for an average of 9.1 years. The interaction between diet and polygenic dementia risk was also tested.
Results
Greater adherence to the MedDiet was associated with a lower risk of dementia (MEDAS continuous: HR = 0.77, 95% CI = 0.65–0.91; PYRAMID: HR = 0.86, 95% CI = 0 .73–1.02 for the highest vs. the lowest tertiles).
There was no significant interaction between MedDiet adherence defined by MEDAS continuous and PYRAMID scores and polygenic dementia risk.
Figure: Association between MedDiet adherence and dementia risk (n = 60,298, including 882 dementia cases). The level of MedDiet adherence was divided into tertiles, and the dashed line reflects the low MedDiet adherence reference group for each MedDiet score.
Conclusions Greater adherence to a MedDiet was associated with a lower risk of dementia, independent of genetic risk, underscoring the importance of diet in dementia prevention interventions. |
Comments
Consumption of a traditional Mediterranean-type diet, rich in foods such as seafood, fruits and nuts, is associated with a reduced risk of dementia, reports a study published in BMC Medicine . People with higher adherence to the Mediterranean diet had up to a 23% lower risk of dementia compared to those with lower adherence to the Mediterranean diet.
Diet may be an important modifiable risk factor for dementia that could be targeted for disease prevention and risk reduction, but previous studies exploring the impact of a Mediterranean diet have generally been limited to sample sizes. small and low numbers of dementia cases. Oliver Shannon and his colleagues analyzed data from 60,298 people in the UK Biobank who had completed a dietary assessment. The authors scored individuals using two measures for adherence to the Mediterranean diet. During the mean follow-up of 9.1 years there were 882 cases of dementia. The authors also considered each individual’s genetic risk for dementia when estimating their polygenic risk, a measure of all the different genes that are related to dementia risk.
The authors found that participants with the highest adherence to the Mediterranean diet had a 23% lower risk of developing dementia compared to those with the lowest adherence score, equivalent to an absolute risk reduction of 0.55%. . There was no significant interaction between polygenic dementia risk and adherence to a Mediterranean diet, which the authors suggest may indicate that the association of greater adherence to a Mediterranean diet and lower dementia risk remains, regardless of genetic risk. dementia individual. This finding was not consistent across sensitivity analyzes and the authors propose that more research is needed to evaluate the interaction between diet and genetics on dementia risk.
The authors caution that their analysis is limited to people who self-reported their ethnicity as white, British, or Irish, as genetic data was only available based on European ancestry, and that more research is needed in a variety of populations to determine the potential benefit. They conclude that, based on their data, a Mediterranean diet with a high consumption of healthy plant-based foods may be an important intervention to incorporate into future strategies to reduce the risk of dementia.
