Table 2.
Summary characteristics of included studies
Author, year | Country | Study design (of data origin) | n | Type dementia | Stage of dementia | Severity proportion (%) | Mean MMSE (SD) | Mean age (SD) | EQ-5D: 3L or 5L | Residence (% institutionalised) | Self or proxy QoL | Proxy type | Mode of administration |
Ankri, 2003 [19] | France | Non-interventional | 142 | Any | Mild-to-severe | 24.3% mild; 47.1% moderate; 27.9% severe | 12.8 (5.6) | 82.9 (8.32) | 3L | 41 | Both | FC & IC | I |
Ashizawa, 2021 [43] | Japan | Prospective cohort study | 287 | AD | Mild-to-severe | NR | NR | 86.1 (6.4) | 5L | 100 | Proxy | FC & IC | SA |
Bhattacharya, 2010 [20] | Denmark | RCT | 321 | AD | Mild | NR | 24.0 (2.7) | 76.2 (7.1) | 3L | 0 | Both | IC | I |
Bonfiglio, 2019 [41] | Japan | Cross-sectional | 141 | NR | Mild | NR | 24.9 (2.6) | 78.8 (6.3) | 5L | 0 | Both | FC & IC | SA |
Bostrom, 2007 [21] | Sweden | RCT | 68 | DLB or AD | Mild-to-severe | NR | 16.9 (0–30) | 77.8 (63–92)c | 3L | 28 | Both | IC | I |
Bryan, 2005 [34] | UK | Non-interventional | 64 | AD and VD | Very mild-to-moderatea | 5% very mild; 56% mild, 39% moderate | 18.0 (5.8) | 76 (53–91)c | 3L | 0 | Proxy | IC & C | SA |
Castro-Monteiro, 2014 [22] | Spain | Multicentre longitudinal cohort | 274 | NR | Mild-to-severea | 18% mild; 26% moderate; 56% severe | NR | 84.7 (6.51) | 3L | 100 | Proxy | IC | I |
Diaz-Redondo, 2014 [23] | Spain | Cross-sectional | 525 | NR | Mild-to-severea | 14% mild; 25% moderate; 62% severe | NR | 85.6 (6.7) | 3L | 100 | Proxy | IC | NR |
Author, year | Country | Study design (of data origin) | n | Type dementia | Stage of dementia | Severity proportion (%) | Mean MMSE (SD) | Mean age (SD) | EQ-5D: 3L or 5L | Residence (% institutionalised) | Self or proxy QoL | Proxy type | |
Easton, 2018 [42] | Australia | Cross-sectional | 541 | NR | Very mild-to-moderate | 55% very mild; 42% mild; 4% moderate | NR | 85.5 (8.5) | 5L | 100 | Both | IC | I |
Ersek, 2010 [24] | Hungary | Cross-sectional | 88 | Any | Very mild-to-severe | 16% very mild; 27% mild; 25% moderate’; 16% severe | 16.7 (7.2) | 77.4 (9.2) | 3Lb | NR | NR | IC | NR |
Farina, 2020 [35] | UK | Cohort | 307 | Any | Mild-to-severe | 36% mild; 33% moderate; 32% severe | 14.9 (9.1) | 80.9 (8.4) | 3L | 21 | Both | IC | SA |
Garre-Olmo, 2017 [25] | Spain | Cross-sectional multicentre | 343 | AD | Mild-to-severe | 32.1% mild; 36.7% moderate; 31.2% severe | 14.2 (6.3) | 78.9 (7.4) | 3L | NR | Proxy | IC | I |
Gonzalez-Velez, 2015 [26] | Spain | Multicentre longitudinal cohort | 412 | NR | Mild/moderate-to-severea | 44% mild/moderate; 56% severe | 13.0 (8.5) | 84.7 (6.5) | 3Lb | 100 | Proxy | FC & IC | SA |
Author, year | Country | Study design (of data origin) | n | Type dementia | Stage of dementia | Severity proportion (%) | Mean MMSE (SD) | Mean age (SD) | EQ-5D: 3L or 5L | Residence (% institutionalised) | Self or proxy QoL | Proxy type | |
Haaksma, 2018 [27] | Netherlands | Multicentre longitudinal prospective cohort | 331 | AD | Mild-to-moderate | 65% very mild | 21.9 (3.7) | 74.9 (10.2) | 3L | NR | Proxy | IC | I |
Heßmann et al., 2016 [28] | Germany | Non-interventional | 395 | AD | Mild-to-severe | 13% very mild; 33% mild; 27% moderate; 28% severe | 18.8 (8.3) | 79 | 3L | 31 | Both | IC | I |
Karlawish, 2008 [1] [44] | USA | Non-interventional | 110 | AD | Very mild-to-moderate | 32% very mild; 39% mild; 29% moderate | 21.3 (4.3) | 76.8 (2.7) | 3L | 0 | Self | n/a | I |
Karlawish, 2008 [2] [45] | USA | Non-interventional | 110 | AD | Very mild-to-moderate | 28% very mild; 37% mild; 35% moderate | 20.8 (4.4) | 76.8 (2.7) | 3L | 0 | Proxy | IC | I |
King 2022 [40] | UK | Cohort study | 243 | Any | Mild-to-severe | ~ 33% each for mild, moderate and severe | 15.9 (9.1) | 80.1 (8.6) | 3L | 18.7 | Both | IC | I |
Kunz, 2010 [29] | Germany | RCT | 399 | NR | Mild-to-moderate | 65% mild; 35% moderate | 18.6 (3.8) | 80.2 (6.7) | 3L | 0 | Both | IC | I |
Kuo, 2010 [48] | Taiwan | Cost analysis | 140 | NR | Mild-to-severe | 24% mild; 30% mild-moderate; 21% moderate; 25% severe | NR | 79.7 | 3Lb | 36 | Both | IC | I |
Author, year | Country | Study design (of data origin) | n | Type dementia | Stage of dementia | Severity proportion (%) | Mean MMSE (SD) | Mean age (SD) | EQ-5D: 3L or 5L | Residence (% institutionalised) | Self or proxy QoL | Proxy type | |
Martin, 2019 [36] | UK | RCT | 1004 | NR | Mild-to-severe | 4% very mild; 23% mild; 39% moderate; 34% severea | NR | 85.5 (58–102.6)c | 3L | 100 | Both | FC & IC | I |
Michalowsky, 2021 [33] | Germany | Interventional study | 77 | Any | Mild-to-moderate | NR | 18.6 (7.4) | 80.2 (6.4) | Both | 0 | Both | FC & IC | I |
Naglie, 2011 [1] [47] | Canada | Longitudinal cohort | 370 | AD | Very mild-to-moderate | 71% very mild; 20% mild; 9% moderate | 22.3 (4.3) | 80.7 (7.8) | 3L | 0 | Self | n/a | I |
Naglie, 2011 [2] [46] | Canada | Longitudinal cohort | 412 | AD | Very mild-to-severe | 64% very mild; 18% mild; 10% moderate; 8% severe | 20.8 (6.2) | 80.7 (7.9) | 3L | 0 | Proxy | IC | I |
Orgeta, 2015 [37] | UK | RCT | 478 | Any | Mild-to-moderatea | 75% mild; 25% moderate | NR | 75.5 (7.3) | 3L | 0 | Both | IC | I |
Schiffczyk, 2010 [30] | Germany | Prospective cohort | 137 | AD or mixed | Mild-to-severe | 37% mild; 48% moderate; 15% severe | 16.9 (6.4) | 69.9 (7.6) | 3L | 0 | Both | IC | I |
Author, year | Country | Study design (of data origin) | n | Type dementia | Stage of dementia | Severity proportion (%) | Mean MMSE (SD) | Mean age (SD) | EQ-5D: 3L or 5L | Residence (% institutionalised) | Self or proxy QoL | Proxy type | |
Sheehan, 2012 [38] | UK | Non-interventional | 112 | Any | Mild-to-severea | 2% very mild; 13% mild; 59% moderate; 27% severe | NR | 85 (66–99)c | 3L | 25 | Both | IC | I |
Trigg, 2015 [39] | UK | Multicentre cohort | 145 | AD | Very mild-to-severe | NR | 15.0 (7.0) | 77.8 (9.2) | 3L | NR | Both | Unclear | I |
van de Beek, 2019 [31] | Netherlands | Multicentre cohort | 138 | AD and DLB | MCI or dementia | NR | 25 [22-27] | 69.7 (5.9) | 3L | NR | Self | n/a | NR |
Vogel, 2006 [32] | Denmark | Prospective cohort | 48 | AD | Very mild | NR | 24.9 (2.3) | 77.0 (5.8) | 3L | NR | Both | IC | PwD – I; Proxy – SA |
AD Alzheimer’s disease, C Clinician, DLB Dementia with Lewy bodies, FC Formal caregiver, IC Informal caregiver, QoL Quality of life, RCT Randomised controlled trial, UK United Kingdom, USA United states of America, VD Vascular dementia, 3L Three-level, 5L Five-level, NR Not reported, n/a Not applicable, MCI Mild cognitive impairment, I Interviewer, SA Self-administered
aDisease severity defined by CDR (versus MMSE in all other studies)
bEQ-5D version not reported, however due to year of the studies – EQ-5D-3L has been assumed
cStudy reported range (not standard deviation)