Table 3.
Dietary Patterns and Cognitive Health: A Review of the Literature.
| Author and Year | Cohort | Study Size | Study Period (Mean Years) | Age at Baseline (Mean Years) | Exposure | Outcome | Effect Estimate |
|---|---|---|---|---|---|---|---|
| Scarmeas et al (2006) | WHICAP | 2258 | 4 | ≥65 | Mediterranean diet score (tertiles) | Incident Alzheimer’s disease | Continuous HR = 0.91 (95% CI: 0.83, 0.98), P-value 0.015T1 (low) = RefT2 HR = 0.85 (95% CI: 0.63, 1.16)T3 HR = 0.60 (95% CI: 0.42, 0.87), P-value trend = 0.007 |
| Scarmeas et al (2009) | WHICAP | 1393 | 4.5 | ≥65 | Mediterranean diet score (tertiles) | Incident mild cognitive impairment and Alzheimer’s disease | Incident MCI:Continuous HR = 0.92 (95% CI: 0.85, 0.99), P-value 0.04T1 (low) = Ref, P-value trend 0.05T2 HR = 0.83 (95% CI: 0.62, 1.12), P-value 0.24T3 HR = 0.72 (95% CI: 0.52, 1.00), P-value 0.05Incident AD:Continuous HR = 0.89 (95% CI: 0.78, 1.02), P-value 0.09T1 (low) = Ref, P-value trend 0.02T2 HR = 0.55 (95% CI: 0.34, 0.90), P-value 0.01T3 HR = 0.52 (95% CI: 0.30, 0.92), P-value 0.02 |
| Scarmeas et al (2009) | WHICAP | 1880 | 5.4 | ≥65 | Mediterranean diet score (tertiles) and physical activity | Incident Alzheimer’s disease | T1 (low) = Ref, P-value trend 0.008T2 HR = 0.98 (95% CI: 0.72, 1.33), P-value 0.88T3 HR = 0.60 (95% CI: 0.42, 0.87), P-value 0.007Low diet score + low PA HR = RefHigh diet score + low PA HR = 0.77 (95% CI: 0.53, 1.13), P-value 0.18Low diet score + high PA HR = 0.81 (95% CI: 0.57, 1.16), P-value 0.26High diet score + high PA HR = 0.65 (95% CI: 0.44, 0.96), P-value 0.03P-value trend: 0.03 |
| Feart et al (2009) | Three City | 1410 | 5 | 75.9 | Mediterranean diet score (tertiles) | Incident Alzheimer’s disease | T1 (low) = RefT2 HR = 0.99 (95% CI: 0.51, 1.94)T3 HR = 0.86 (95% CI: 0.39, 1.88), P-value trend: 0.72 |
| Feart et al (2009) | Three City | 1410 | 5 | 75.9 | Mediterranean diet score (tertiles) | Incident dementia | T1 (low) = RefT2 HR = 1.11 (95% CI: 0.63, 1.94)T3 HR = 1.12 (95% CI: 0.60, 2.10), P-value trend: 0.72 |
| Gu et al (2010) | WHICAP | 1219 | 4 | ≥65 | Mediterranean diet score (tertiles) | Incident Alzheimer’s disease | Continuous HR = 0.87 (95% CI: 0.78, 0.97), P-value 0.01T1 (low) = RefT2 HR = 0.56 (95% CI: 0.36, 0.86), P-value 0.01T3 HR = 0.68 (95% CI: 0.42, 1.08), P-value 0.10P-value trend: 0.06 |
| Morris et al (2015) | Rush Memory and Aging Project | 923 | 4.5 | 58-98 (mean ~81 years) | Mediterranean, MIND, and DASH diets | Incident Alzheimer’s disease | Mediterranean diet:T1 (low) = RefT2 HR = 0.81 (95% CI: 0.53, 1.21)T3 HR = 0.49 (95% CI: 0.29, 0.85), P-value trend: 0.01MIND diet:T1 (low) = RefT2 HR = 0.64 (95% CI: 0.42, 0.97)T3 HR = 0.48 (95% CI: 0.29, 0.79), P-value trend:0.003DASH diet:T1 (low) = RefT2 HR = 0.98 (0.64, 1.46)T3 HR = 0.60 (0.37, 0.96), P-value trend: 0.06 |
| Roberts et al (2010) | Rochester Epi. Project | 1141 | 2.2 (median) | 70-89 | Mediterranean diet score (tertiles) | Incident MCI or dementia | T1 (low) = RefT2 HR = 0.79 (95% CI: 0.51, 1.21), P-value: 0.28T3 HR = 0.75 (95% CI: 0.46, 1.21), P-value: 0.24 |
| Tsivgoulis et al (2013) | REGARDS | 17 478 | 4 | 64.4 | Mediterranean diet score (dichotomous) | Incident cognitive impairment | Low adherence = RefHigh OR = 0.87 (95% CI: 0.76, 1.00), P-value 0.0460Nondiabetics:High OR = 0.81 (95% CI: 0.70, 0.94), P-value 0.0066Diabetics:High OR = 1.27 (95% CI: 0.95, 1.71), P-value 0.1063 |
| Samieri et al (2013) | NHS | 16,058 | 13 | 74.3 | Alternate Mediterranean diet (quintiles) | Cognitive status, global cognition, and verbal memory | Cognitive status (mean difference in score):Q1 = Ref, P-value trend: 0.004Q2 = 0.02 (95% CI: −0.02, 0.07), Q3 = 0.03 (95% CI: −0.01, 0.08)Q4 = 0.06 (95% CI: 0.02, 0.11), Q5 = 0.06 (95% CI: 0.01, 0.11)Global cognitive function (mean difference in score):Q1 = Ref, P-value trend: 0.002Q2 = 0.02 (95% CI: −0.01, 0.05), Q3 = 0.03 (95% CI: −0.00, 0.06)Q4 = 0.04 (95% CI: 0.01, 0.07), Q5 = 0.05 (95% CI: 0.01, 0.08)Verbal memory (mean difference in score):Q1 = Ref, P-value trend <0.001Q2 = 0.01 (95% CI: −0.03, 0.04), Q3 = 0.03 (95% CI: −0.01, 0.06)Q4 = 0.04 (95% CI: 0.01, 0.08), Q5 = 0.06 (95% CI: 0.03, 0.10) |
| Samieri et al (2013) | WHS | 6174 | 5.6 | 71.9 | Alternate Mediterranean diet (quintiles) | Global cognition and verbal memory | Global cognitive function (mean difference in score):Q1 = Ref, P-value trend 0.63Q2 = 0.03 (95% CI: −0.02, 0.08), Q3 = 0.02 (95% CI: −0.03, 0.06)Q4 = 0.02 (95% CI: −0.03, 0.07), Q5 = 0.02 (95% CI: −0.03, 0.06)Verbal memory (mean difference in score):Q1 = Ref, P-value trend 0.44Q2 = 0.04 (95% CI: −0.02, 0.09), Q3 = 0.01 (95% CI: −0.04, 0.06)Q4 = 0.03 (95% CI: −0.02, 0.08), Q5 = 0.03 (95% CI: −0.02, 0.07) |
| Wengreen et al (2013) | Cache County Memory | 3580 | 10.6 | ≥65 | Mediterranean diet score (quintiles) | Cognitive performance (difference −10.6 years) | Q1 = RefQ2 = 0.68 ±- 0.29, Q3 = 0.62 ± 0.29Q4 = 0.83 ± 0.29, Q5 = 0.94 ± 0.29P-value trend: 0.022, P-value Q5 vs Q1: 0.0014 |
| Kesse et al (2013) | SU.VI.MAX | 3083 | 13 | 52 | Mediterranean diet and Mediterranean style dietary pattern score (tertiles) | Cognitive performance (mean difference over 13 years) | Mediterranean diet adherence:T1 = −0.18 (−1.09, 0.73)T2 = 0.58 (−0.21, 1.37)T3 (high) = Ref, P-value trend = 0.27Mediterranean style dietary pattern adherence:T1 = −0.41 (−1.23, 0.40)T2 = −0.17 (−0.96, 0.63)T3 (high) = Ref, P-value trend 0.12 |
| Psaltopoulou et al (2008) | EPIC-Greece | 732 | 6.4-12.6 | ≥60 | Mediterranean diet score | Cognitive function | Mean MMSE score:β (per unit change in MeDi score) = 0.05(95% CI: −0.09, 0.19), P-value = 0.485 |
| Cherubin et al (2012) | PATH Through Life | 1528 | 4 | 60-64 | Mediterranean diet score | Cognitive impairment or dementia | Mild cognitive impairment: OR = 1.41 (95% CI: 0.95, 2.10), P-value 0.087Clinical dementia rating: OR = 1.18 (95% CI: 0.88, 1.57), P-value 0.266Any mild cognitive disorder: OR = 1.20 (95% CI: 0.98, 1.47), P-value 0.079 |
| Tangney et al (2013) | CHAP | 3790 | 7.6 | 75.4 | Mediterranean diet score | Cognitive decline | Global cognitive score:MedDiet score β = 0.0014,P-value 0.0004MedDiet wine score β = 0.0014, P-value 0.0009 |
| Vercambre et al (2012) | WACS | 2504 | 5.4 | ≥65 | Mediterranean diet score (tertiles) | Cognitive decline | Difference in annual rate of global cognitive decline:T1 (low) = RefT2 = 0.01 (95% CI: −0.01, 0.02)T3 = 0.00 (95% CI: −0.02, 0.01), P-value trend: 0.88 |
| Qin et al (2015) | CHNS | 1650 | 5.3 | ≥55 | Adapted Mediterranean diet score (tertiles) | Cognitive decline/change | Difference in mean rate of change in cognitive function:T1 β = RefT2 β = 0.018 (−0.019, 0.056)T3 β = 0.042 (0.001, 0.027) |
| Martínez-Lapiscina et al (2013) | PREDIMED (RCT) | 522 | 6.5 | 74.6 | Mediterranean diet + nuts or EVOO | Cognitive performance | Mean difference in MMSE score:Low fat = RefMedDiet + EVOO: +0.62 (95% CI: 0.18, 1.05), P-value 0.005MedDiet + Nuts: +0.57 (95% CI: 0.11, 1.03), P-value 0.015Mean difference in CDT score:Low fat = RefMedDiet + EVOO: +0.51 (95% CI: 0.20, 0.82), P-value 0.001MedDiet + Nuts: +0.33 (95% CI: 0.003, 0.67), P-value 0.048 |
| Valls-Pedret et al (2015) | PREDIMED (RCT) | 447 | 4.1 (median) | 66.9 | Mediterranean diet + nuts or EVOO | Cognitive performance change | Change in cognitive composites score:Low-fat = −0.38 (−0.57, −0.18)MedDiet + EVOO OR = 0.05 (−0.11, 0.21), P-value 0.005MedDiet + Nuts OR = −0.05 (−0.27, 0.18), P-value <0.05 |
| Martínez-Lapiscina et al (2013) | PREDIMED (RCT) | 285 | 6.5 | 74.1 | Mediterranean diet + nuts or EVOO | Cognitive status (mild cognitive impairment) | Low-fat = RefMedDiet + EVOO OR = 0.341 (95% CI: 0.120, 0.969), P-value 0.044MedDiet + Nuts OR = 0.563 (95% CI: 0.222, 1.427), P-value 0.226 |
| Kesse et al (2011) | SU.VI.MAX | 2135 | 13 | 52.6 men; 51.6 women | French National Nutrition and Health Program (quartiles) | Cognitive performance | Verbal Memory:β = 0.41 (95% CI: 0.17, 0.64) P-value <.05Q1 = 48.81 ± 0.82, Q2 = 49.59 ± 0.83Q3 = 50.48 ± 0.83, Q4 = 50.43 ± 0.85, P-value trend = 0.003Executive functioning:β = −0.09 (95% CI: −0.33, 0.14), P-value >.05Q1 = 49.46 ± 0.84, Q2 = 49.66 ± 0.85Q3 = 49.90 ± 0.85, Q4 = 49.04 ± 0.86, P-value trend = 0.60 |
| Kesse et al (2012) | SU.VI.MAX | 3054 | 13 | 52.1 | Healthy and traditional dietary patterns (quartiles) | Cognitive performance (mean test score) | Global cognitive function:Q1 = 48.9 ± 0.7, Q2 = 49.4 ± 0.7Q3 = 50.8 ± 0.7, Q4 = 50.1 ± 0.7, P-value trend: 0.001Verbal memory:Q1 = 49.1 ± 0.7, Q2 = 49.5 ± 0.7Q3 = 50.6 ± 0.7, Q4 = 50.3 ± 0.7, P-value trend: 0.01Executive functioning:Q1 = 49.3 ± 0.7, Q2 = 49.6 ± 0.7Q3 = 50.6 ± 0.7, Q4 = 49.8 ± 0.7, P-value trend 0.13 |
| Shatenstein et al (2012) | NuAge | 1488 | 3 | 74.1 men; 74.4 women | Canadian Healthy Eating Index | Cognitive performance | β = −0.0008 ± 0.00403, P-value = 0.852 |
| Wengreen et al (2013) | Cache County Memory | 3580 | 10.6 | ≥65 | DASH diet score (quintiles) | Cognitive performance (difference over 10.6 years) | Q1 = RefQ2 = 0.35 ± 0.29, Q3 = 0.68 ± 0.29Q4 = 0.96 ± 0.29, Q5 = 0.97 ± 0.29, P-value trend: 0.0001, P-value Q5 vs Q1: 0.0009 |
| Smith et al (2010) | ENCORE (RCT) | 124 | 4 months | 52.3 | DASH diet score | Cognitive function | Psychomotor speed test:DASH P-value 0.36, DASH + WM P-value 0.023Executive function-memory-learning tests:DASH: no significant P-valuesDASH + WM P-values: 0.026, 0.045, and 0.024 |
| Wengreen et al (2013) | Cache County Memory | 3580 | ~11 | ≥65 | Recommended food score (quartiles) | Cognitive decline (decrease in score over 11 years) | Q1 = −5.15 ± 0.69 Least Varied DietQ2 = −3.98 ± 1.0, Q3 = −4.91 ± 1.08Q4 = −3.41 ± 0.79 Most Varied DietP-value Q5 vs Q1: 0.013 |
| Tangney et al (2013) | CHAP | 3790 | 7.6 | 75.4 | Healthy eating index score | Cognitive decline | Global cognitive score: β = 0.0002, P-value = 0.214 |
| Tsai et al (2015) | TLSA | 23578 | 8 | 73 | Traditional dietHealthy diet | Cognitive decline | Traditional diet: OR = 1.37 (0.85, 2.21), P-value 0.20Healthy diet: OR = 1.13 (0.53, 2.41), P-value 0.75 |
| Morris et al (2015) | Rush Memory and Aging Project | 960 | 4.7 | 81.4 | MIND diet | Cognitive decline | Global cognitive score: β = 0.0092, P-value <0.0001 |
Abbreviations: HR, hazard ratio; CI, confidence interval; MCI, mild cognitive impairment; PA, physical activity; OR, odds ratio; MMSE, Mini-Mental State Examination; RCT, randomized controlled trial.