TABLE 1.
Description of included studies1
| Source | Study design | Sample size, n | Mean age, y | Female, % | Participant source | Country of origin | Participant cognitive status at baseline |
| Chan et al., 2013 (29) | Cross-sectional | 3670 | 72 | 48 | Cohort from Hong Kong | China | Mixed cognitive health status |
| Crichton et al., 2013 (30) | Cross-sectional | 1183 | 40–65* | 64 | South Australian electoral rolls | Australia | Mixed cognitive health status |
| Gardener et al., 2012 (31) | Cross-sectional | 652 | 72 | 58 | AIBL Study of Ageing | Australia | Mixed healthy controls and participants with MCI and AD |
| Katsiardanis et al., 2013 (32) | Cross-sectional | 557 | 65 | 57 | Residents of Valestino | Greece | Mixed cognitive health status |
| Ye et al., 2013 (33) | Cross-sectional | 1269 | 57 | Not reported | Boston Puerto Rican Health Study | United States | Mixed cognitive health status |
| Scarmeas et al., 2006 (34) | Cross-sectional, case-control | 1984 | 76 | 68 | WHICAP project | United States | Subjects with AD and nondemented subjects |
| Cherbuin and Anstey, 2012 (35) | Longitudinal | 1528 | 64 | 51 | PATH study | Australia | Cognitively healthy |
| Corley et al., 2013 (36) | Longitudinal | 882 | 70 | 50 | Lothian Birth Cohort 1936 study | Scotland | Mixed cognitive health status |
| Feart et al., 2009 (37) | Longitudinal | 1410 | 76 | 63 | Three-City study | France | Elderly without diagnosis of dementia |
| Kesse-Guyot et al., 2013 (38) | Longitudinal | 3083 | 52 | 46 | SU.VI.MAX | France | Cognitively healthy participants |
| Koyama et al., 2015 (39) | Longitudinal | 2326 | 75 | 51 | Health ABC study | United States | No cognitive assessment at baseline |
| Olsson et al., 2015 (40) | Longitudinal | 564 | 70 | 0 | Uppsala longitudinal study | Sweden | Cognitively healthy participants |
| Psaltopoulou et al., 2008 (41) | Longitudinal | 732 | 60 | 65 | EPIC–Greece study | Greece | No cognitive assessment at baseline |
| Samieri et al., 2013 (42) | Longitudinal | 10,670 | 59 | 100 | Nurses’ Health Study | United States | Cognitively healthy participants |
| Samieri et al., 2013 (43) | Longitudinal | 6174 | 66 | 100 | Women’s Health Study | United States | Cognitively healthy participants |
| Samieri et al., 2013 (44) | Longitudinal | 16,058 | 74 | 100 | Nurses’ Health Study | United States | Cognitively healthy participants |
| Scarmeas et al., 2009 (45) | Longitudinal | 282 | 77 | 68 | WHICAP project | United States | Subjects with AD and nondemented subjects |
| Scarmeas et al., 2009 (46) | Longitudinal | 1875 | 77 | 68 | WHICAP project | United States | Participants with MCI and cognitively healthy subjects |
| Scarmeas et al., 2006 (47) | Longitudinal | 2258 | 77 | 69 | WHICAP project | United States | Cognitively healthy participants |
| Tangney et al., 2014 (48) | Longitudinal | 826 | 82 | 74 | MAP project | United States | No cognitive assessment at baseline |
| Titova et al., 2013 (49) | Longitudinal | 194 | 70 | 48 | PIVUS study | Sweden | Mixed cognitive health status |
| Tsivgoulis, 2013 (50) | Longitudinal | 17,478 | 64 | 57 | REGARDS | United States | Cognitively healthy participants |
| Vercambre et al., 2012 (51) | Longitudinal | 2504 | >65* | 100 | Women’s Antioxidant Cardiovascular Study | United States | Cognitively healthy participants |
| Wengreen et al., 2013 (52) | Longitudinal | 3831 | 65 | 57 | CCMS | United States | Cognitively healthy participants |
| Gu et al., 2010 (53) | Longitudinal/cross-sectional | 1219 | 77 | 67 | WHICAP project | United States | Cognitively healthy participants |
| Roberts et al., 2010 (54) | Longitudinal/cross-sectional | 1233 | 70–89* | 49 | Rochester Epidemiology Project | United States | No cognitive assessment at baseline |
| Tangney et al., 2011 (55) | Longitudinal/cross-sectional | 3790 | 75 | 62 | CHAP project | United States | No cognitive assessment at baseline |
| Martínez-Lapiscina et al., 2013 (56) | RCT | 522 | 75 | 55 | PREDIMED RCT | Spain | No cognitive assessment at baseline |
| Martínez-Lapiscina et al., 2013 (57) | RCT | 285 | 67 | 55 | PREDIMED RCT | Spain | No cognitive assessment at baseline |
| Martínez-Lapiscina et al., 2014 (58) | RCT | 522 | 67 | 44 | PREDIMED RCT | Spain | No cognitive assessment at baseline |
| McMillan et al., 2011 (59) | RCT | 25 | 21 | 27 | Australian residents | Australia | No information on cognitive status at baseline |
| Wardle et al., 2000 (60) | RCT | 176 | 53 | 52 | London and Southeast England residents | England | No cognitive assessment at baseline |
1
*Mean age not provided. AD, Alzheimer disease; AIBL, Australian Imaging, Biomarkers, and Lifestyle; CCMS, Cache County Memory Study; CHAP, Chicago Health and Aging Project; EPIC, European Prospective Investigation into Cancer and Nutrition; Health ABC, Health, Aging, and Body Composition; MAP, Memory and Aging Project; MCI, mild cognitive impairment; PATH, Personality and Total Health Through Life; PIVUS, Prospective Investigation of the Vasculature in Uppsala Seniors; PREDIMED, PREvención con DIeta MEDiterránea; RCT, randomized controlled trial; REGARDS, Reasons for Geographic and Racial Differences in Stroke; SU.VI.MAX, Supplementation with Vitamins and Mineral Antioxidants; WHICAP, Washington/Hamilton Heights–Inwood Columbia Aging Project.