Nutrients in the Prevention of Alzheimer’s Disease

Table 2

Summary of the clinical studies that investigate the role of the three dietary patterns (MeDi, DASH, and MIND) in counteracting cognitive decline, incidence of dementia, and/or AD and AD-related mortality.

Authors (year)	Type of diet	Study design	Study population	Results	Follow-up/length of intervention	Reference
Scarmeas et al. (2006)	MeDi	Cross-sectional	Elderly Americans (NY)	Higher adherence to the MeDi was associated with lower risk for AD (odds ratio, 0.76; 95% confidence interval, 0.67-0.87; P.001)	NA	[22]
Gardener et al. (2012)	MeDi	Cross-sectional (AIBL) study	Elderly Australians	Compared with healthy controls, subjects with AD and MCI had a lower mean MeDi score ( and <0.05, respectively); each additional unit in the MeDi score was associated with 13–19% lower odds of being in the MCI category, and 19–26% lower odds of being in the AD category	NA	[23]
Scarmeas et al. (2006b)	MeDi	Cohort	Elderly Americans (NY)	Higher adherence to the MeDi was associated with significantly lower risk for development of AD. Each additional unit of the MeDi score was associated with 9 to 10% less risk for development of AD	4 years	[25]
Scarmeas et al. (2009)	MeDi	Cohort	Elderly Americans (NY)	Both higher Mediterranean-type diet adherence and higher physical activity were independently associated with reduced risk for AD	5.4 years	[26]
Gu et al. (2010)	MeDi	Cohort	Elderly Americans (NY)	Significant association between MeDi score and reduction in risk of AD: compared to those in the lowest tertile of MeDi, subjects in the highest tertile had a 34% less risk of developing AD ()	3.8 years	[27]
Morris et al. (2015)	MeDi; DASH; MIND	Cohort	Elderly Americans (Chicago)	Participants in both the middle and the highest tertiles of MIND scores had a statistically significant reduction in AD rate compared to those in the lowest tertile (53% and 35% reduction, respectively). Subjects with the highest adherence to the MeDi and DASH had a 54% and 39% lower risk of developing AD, respectively, compared to those in the lowest tertile (, 95% CI 0.26, 0.79)	4.5 years	[28]
Scarmeas et al. (2009b)	MeDi	Cohort	Elderly Americans (NY)	Significant association between MeDi adherence and MCI conversion to AD, with a 48% less risk of developing AD (HR: 0.52; 95% CI: 0.30, 0.91; ) for highest vs. lowest tertile on MeDi score	4.3 years	[29]
Scarmeas et al. (2007)	MeDi	Cohort	Elderly Americans (NY)	Higher adherence to the MeDi is associated with lower mortality in AD patients	4.4 years	[30]
Anastasiou et al. (2017)	MeDi	Cross-sectional	Elderly Greeks	Adherence to MeDi is positively associated with a decreased likelihood of dementia and better cognitive performance in many domains, especially memory	NA	[31]
Martinez-Lapiscina et al. (2013)	MeDi	RCT; (PREDIMED)	Individuals at high CV risk (from Spain)	A dietary intervention with MeDi enriched with either EVOO or nuts appears to improve cognition compared with a low-fat diet	6.5 years	[43]
Valls-Pedret et al. (2015)	MeDi	RCT; (PREDIMED)	Individuals at a high CV risk (from Spain)	A MeDi supplemented with EVOO or nuts is associated with improved composite measures of cognitive function	4.1 years	[44]
Knight et al. (2016)	MeDi	RCT; (MedLey)	Elderly Australians	No evidence of a beneficial effect of a MeDi intervention on cognitive function among healthy older adults	6 months	[45]
Marseglia et al. (2018)	MeDi	RCT; (NU-AGE)	Five European populations	Improved cognitive performance in both the active and the control groups, with no additional diet-related cognitive improvements	1 year	[46]
Tangney et al. (2014)	MeDi; DASH	Cohort	Older Americans (Chicago)	A 1-unit difference in DASH score and in MedDietScore are associated with a slower rate of global cognitive decline by 0.007 standardized units (, ) and by 0.002 standardized units (, ), respectively	4.1 years	[67]
Berendsen et al. (2017)	DASH	Cohort	Older American women	Long-term adherence to the DASH diet is associated with better average cognitive function but not with change in cognitive function over the follow-up period	6 years	[69]
Haring et al. (2016)	MeDi; DASH	Cohort	Older American women	No association between aMED and DASH scores and incidence of MCI or dementia in older women generally or in those with hypertension	9.1 years	[70]
Smith et al. (2010)	DASH	RCT; (ENCORE)	Overweight and sedentary individuals (USA)	Slight improvements in psychomotor speed after the intervention with the DASH diet	4 months	[71]
McEvoy CT et al. (2017)	MeDi; MIND	Cross-sectional	Older U.S. adults	Greater adherence to the MeDi and MIND diet is independently associated with better cognitive function and lower risk of cognitive impairment	NA	J Am Geriatr Soc. (2017) 65:1857–1862