Table 1.
Characteristics of included studies
| Study ID | Country | Sample size (dementia) | Gender ratio (dementia; % female) | Mean age (dementia) | Young vs late onset/age of onset | Dementia syndrome | Severity (CDR)/global cognition (MMSE) |
|---|---|---|---|---|---|---|---|
| Akyol et al. (2020) | Turkey | 106 | 46.23% | 72.25 | NR | AD, VaD, FTD | MMSE = 15.77 |
| Balci et al. (2011) | Turkey | 26 | 80.80% | 76.23 | NR | AD | MMSE = 15.69 |
| Bhat et al. (2021) | India | 76 | 28.90% | 58.05 | NR | VaD | CDR = 1.65 |
| Benedict et al. (1999) | USA | 13 | 92.00% | 73.43 | NR | VaD | MMSE = 22.4 |
| Breitve et al. (2018) | Norway | 196 | 37.00% | 76.06 | NR | AD, DLB | CDR = 0.87 |
| Bronnick et al. (2011) | Norway | 172 | 38.00% | 73.21 | NR | PDD | MMSE = 20.11 |
| Bylsma et al. (1994) | USA | 180 | 58.00% | 72.38 | Late (68.35) | AD | CDR = 1.2 |
| Camargo et al. (2018) | Brazil | 40 | 35.00% | 70.08 | NR | PDD | SCOPA-Cog = 11.25 |
| Chwiszczuk et al. (2017) | Norway | 246 | 56.56% | 75.52 | NR | AD, DLB, PDD | MMSE = 23.64 |
| Contador-Castillo et al. (2009) | Spain | 23 | 65.22% | 75.31 | NR | AD | MMSE = 22.73 |
| D’Antonio et al. (2019) | Italy | 32 | 50.00% | 74.28 | NR | AD | MMSE = 19.63 |
| de Oliveira et al. (2015a) (‘Correlations’) | Brazil | 217 | 67.70% | 78 | Late (73.19) | AD | CDR 1, 2, 3 |
| de Oliveira et al. (2015b)2 ‘contrasts’ | Brazil | 39 | 56.41% | 78 | Late | AD, PDD, LBD | MMSE = 17.52 |
| de Oliveira et al. (2020) | Brazil | 51 | 39.20% | 77.76 | NR | PD, LBD | MMSE = 15.82, CDR = 11.46 |
| DeMichele-Sweet et al. (2011) | USA | 2317 | 57.00% | 78.4 | Late (72.3) | AD | MMSE 17.7 |
| de Paula et al. (2016) | Brazil | 93 | NR | 74.57 | NR | AD | MMSE = 20.59 |
| Drijgers et al. (2011) | The Netherlands | 260 | 56.00% | 74.4 | NR | AD | MMSE 20.3 |
| Eikelboom et al. (2021) | The Netherlands | 1090 | 52.40% | 65.9 | NR | AD | MMSE = 20.3 |
| Eustace et al. (2001) | Ireland | 150 | 69.00% | 76.48 | NR | AD | MMSE = 19.31 |
| Fahlander et al. (1999) | Sweden | 54 | 76.00% | 83.93 | NR | AD | MMSE 19.57 |
| Fernández et al. (2010) | Spain | 1014 | 65.00% | 77.19 | NR | AD | NR |
| Fernandez-Martinez et al. (2010) | Spain | 99 | 56.60% | 75.31 | NR | AD | MMSE = 21.93 |
| Fillit et al. (2021) | USA | 6265 | 69.00% | 80.47 | NR | AD and other aetiologies | NR |
| Fitz and Teri (1994) | USA | 91 | 55.00% | 73.49 | NR | AD | MDRS = 102.52 |
| Flynn et al. (1991) | USA | 33 | 9.00% | 73.36 | NR | AD / MID | MMSE = 16.5 |
| Gallassi et al. (2001) | Italy | 33 | 29.00% | 77.1 | NR | AD | MMSE = 15.4 |
| Gallo et al. (2008) | USA | 48 | 65.00% | 79 | NR | AD, VaD | MMSE = 23 |
| Galynker et al. (1995) | USA | 26 | 57.70% | 78.8 | NR | AD/multi-infarct dementia | MMSE = 16.8 |
| Gilley et al. (1991) | USA | 230 | 67.00% | 71.54 | NR | AD | MMSE 12.57 |
| Grossi et al. (2013) | Italy | 61 | 46.00% | 69.54 | NR | AD, PDD | MMSE = 22.13 |
| Hallikainen et al. (2012) | Finland | 236 | 51.30% | 75.11 | NR | AD | MMSE = 21.5 |
| Harwood et al. (2000) | USA | 114 | 63.00% | 78.8 | NR | AD | MMSE = 17.8 |
| Hopkins and Libon (2005) | USA | 48 | NR | 79.06 | NR | VaD | MMSE = 21/33 |
| Ito et al. (2007) | Japan | 40 | 68.00% | 77.8 | NR | AD | CASI = 25.15 |
| Janzing et al. (2005) | The Netherlands | 60 | 88.30% | 86.3 | NR | NR | NR |
| Keator et al. (2019) | USA | 58 | 50.00% | 69.19 | NR | PPA | NR |
| Kuzis et al. (1999) | Argentina | 184 | NR | 70.88 | NR | AD | MMSE = 22.49 |
| Kwak et al. (2013) | Korea | 230 | 61.73% | 74.66 | Late (71.88) | AD | CDR = 1.06 |
| Lam et al. (2006) | China | 125 | 58.40% | 82.04 | NR | AD, VaD | MMSE = 8.62 |
| Lee et al. (2007) | Japan | 50 | 86.00% | 81.36 | NR | AD | MMSE = 15.58 |
| Lee et al. (2012) | Taiwan | 127 | 40.15% | 77 | NR | PDD | MMSE = 17 |
| Lee et al. (2019) | Korea | 1247 | 56.60% | 72.65 | NR | AD | MMSE = 20.21 |
| Levy et al. (1998) | USA | 28 | 46.43% | 63 | NR | AD, FTD | MMSE = 16.5 |
| Logsdon et al. (1998) | USA | 193 | 49.00% | 76.8 | NR | AD | MMSE = 17.4 |
| Lopez et al. (1991) | USA | 17 | 76.00% | 68 | NR | AD | MMS = 18.7 |
| Machado et al. (2020) | Brazil | 32 | 59.00% | 75.84 | AOO = 71.14 | DLB | MMSE = 17.72 |
| Mariano et al. (2020) | Brazil | 42 | 45.23% | 68.31 | YOD (64.08) | AD, FTD | MMSE = 25.06 |
| McPherson et al. (2002) | USA | 44 | 69.00% | 75.72 | NR | AD | MMSE = 22.57 |
| Migliorelli et al. (1995) | Argentina | 103 | 74.00% | 73.58 | Late (69.21) | AD | NR |
| Mizrahi et al. (2006) | Argentina | 771 | NR | 71.1 | NR | AD | MMSE = 21.8 |
| Montagnese et al. (2022) | UK | 284 | 49.00% | 75.42 | NR | DLB, PDD | MMSE = 26.05 |
| Na et al. (2018) | South Korea | 289 | 71.00% | 77.68 | NR | AD | CDR = 1, MMSE = 20.83 |
| Naarding et al. (2007) | The Netherlands | 54 | 46.00% | 73.7 | NR | Post-stroke dementia | MMSE = 19.8 |
| Nagata et al. (2010) | Japan | 50 | 78.00% | 78.16 | NR | AD | MMSE = 19.38 |
| Nagata et al. (2017) | Japan | 421 | 56.00% | 77.9 | NR | AD | MMSE = 15 |
| Nakaaki et al. (2007) | Japan | 42 | 52.38% | 71.4 | NR | AD | MMSE = 19.55 |
| Nakaaki et al. (2008) | Japan | 88 | 55.00% | 71.23 | NR | AD | MMSE = 19.76 |
| Nakatsuka et al. (2014) | Japan | 142 | 66.90% | 80 | NR | AD | MMSE 14.4 |
| Onyike et al. (2007) | USA | 316 | NR | NR | NR | NR | MMSE = 14.32 |
| Pagonabarraga et al. (2008) | Spain | 30 | 43.00% | 77.17 | NR | PDD | MDRS = 102.33 |
| Park et al. (2019) | Korea | 1128 | 62.00% | 73 | NR | AD | MMSE = 20.1 |
| Perneczky et al. (2009) | Germany | 21 | 48.00% | 71.1 | Young (63.1) | DLB | MMSE = 20.8 |
| Perri et al. (2014) | Italy | 86 | 39.53% | 69.06 | NR | AD, frontal variant FTD, SIVD, LBD | CDR = 0.72, MMSE = 22.53 |
| Perri et al. (2018) | Italy | 20 | 55.00% | 76.83 | NR | AD | MMSE = 22.2 |
| Pezzoli et al. (2019) | Italy | 52 | 46.00% | 70.98 | NR | DLB | MMSE = 25.42 |
| Qian et al. (2018) | Canada | 900 | 44.00% | 77.11 | Late | AD | MMSE = 13.17 |
| Quaranta et al. (2015) | Italy | 108 | 64.00% | 73.3 | NR | AD | MMSE = 17.2 |
| Reed et al. (1993) | USA | 57 | NR | 74.43 | NR | AD | MMSE = 19.4 |
| Rochat et al. (2013) | Switzerland | 30 | NR | 72.03 | NR | AD | NR |
| Rolland et al. (2007) | France | 682 | 72.00% | 77.4 | Late (74.1) | AD | MMSE = 20.1 |
| Ross et al. (1998) | USA | 1486 | 69.00% | 77.01 | NR | AD | MMSE = 16.62 |
| Rozum et al. (2019) | USA | 56 | 67.90% | 85.68 | NR | VaD | SCIP total = 154.77 |
| Ruiz et al. (2018) | Spain | 90 | 59.00% | 76 | NR | AD | MMSE = 22.4 |
| Sánchez-Rodríguez (2004) | Spain | 58 | 57.00% | 73.34 | Late | AD | MMSE = 24.3 |
| Senanarong et al. (2005) | Thailand | 73 | 72.60% | 70.28 | NR | AD | MMSE = 18.42 |
| Serra et al. (2010) | Italy | 54 | 66.67% | 73.1 | NR | AD | MMSE = 20.72 |
| Shin et al. (2014) | Korea | 63 | 73.00% | 74.83 | NR | AD | MMSE = 16.73 |
| Soleman Hernandez et al. (2012) | Brazil | 37 | 78.00% | 78.8 | NR | AD | MMSE = 17.2 |
| Starkstein et al. (2005) | Argentina | 150 | 90.00% | 70.49 | NR | AD | MMSE = 23.09 |
| Starr and Lonie (2007) | UK | 556 | 69.96% | 77.3 | NR | AD | MMSE = 19.2 |
| Strauss and Sperry (2002) | USA | 100 | 50.00% | 75 | NR | AD | MMSE = 18.55; CDR = 1.62 |
| Sultzer et al. (1992) | USA | 61 | NR | 73 | NR | AD | MMSE = 10 |
| Sultzer et al. (2014) | USA | 88 | 19.00% | 78 | NR | AD | MMSE = 19.3 |
| Van der Mussele et al. (2013) | Belgium | 402 | 67.00% | 80.1 | Late (76.8) | AD | MMSE = 15.2, Global Deterioration Scale = 5.1 |
| Van der Mussele et al. (2015) | Belgium | 393 | 67.00% | 80.1 | Late (76.9) | AD | MMSE = 15.1 |
| Wagner et al. (1995) | USA | 614 | 69.00% | 79 | NR | Primarily AD | MMSE = 7.8 |
| Welsh et al. (1996) | UK | 18 | 94.40% | NR | NR | AD | NR |
| Wu (2014) | Taiwan | 179 | 39.00% | 78.4 | NR | NR | NR |
| Yeager and Hyer (2008) | USA | 68 | 60.00% | 77 | NR | AD, dementia-NOS | NR |
| Zahodne et al. (2015) | USA | 517 | 57.00% | 74.19 | NR | AD | NR |
AD Alzheimer’s disease, BPSD behavioural and psychological symptoms of dementia, CDR clinical dementia rating, Dementia-NOS dementia not otherwise specified, DLB dementia with Lewy bodies, FTD frontotemporal dementia, MCI mild cognitive impairment, MMSE Mini-Mental State Examination, MID multi-infarct dementia, NPS neuropsychiatric symptoms, NR not reported, PPA primary progressive aphasia, PDD Parkinson’s disease dementia, SCOPA-Cog Scales for Outcomes in PArkinson’s disease-COGnition, SIVD subcortical ischemic vascular dementia, UK United Kingdom, USA United States of America, VaD vascular dementia