Table 1. Study Overviewa.
| Source | Cohort Nationality | Setting | Population | Exclusion Criteria | No. | Age, Mean (SD), y | Female, No. (%) | Apathy Measure | Apathy Cases, No. (%) |
|---|---|---|---|---|---|---|---|---|---|
| Bartolini et al,29 2005 | Italy | Memory clinic | SCC | Dementia, MCI, abnormal NP test scores | 222 | 69.2 (4.8) | 141 (64) | BDIb | 35 (15.8) |
| Burke et al,30 2016 | United States | Database of memory clinics | SCC | CDR >0, abnormal NP test scores | 1567 | 71.2 (10.9) | 988 (63) | NPI-Q | 297 (18.9) |
| Chan et al,39 2011 | China | CD sample and AR volunteers | NCI (35%); MCI (65%) | Age <60 y | 321 | 77.3 (8.3) | 225 (70) | NPI-i | 45 (14.0) |
| Brodaty et al,37 2012 | Australia | CD sample | NCI (63%); MCI (37%) | Inclusion, age 70-90 y; exclusion, MMSE<24, dementia, neurological disease, psychiatric/somatic disorders impairing cognition, developmental disability, malignancy, non-English, CI without SCC | 630 | 78.2 (4.6) | 346 (55) | NPI-i | 14 (2.2) |
| Van der Linde et al,38 2013 | United Kingdom | Population based | MCI (S) | Dementia, Parkinson disease, MMSE>26 | 879 | 56% ≥ 75c | 927/1416 (65) | GMS-AGECAT | 159 (18.1) |
| Pink et al,35 2015 | United States | Population based | MCI | None reported | 332 | Median (IQR): 82.1 (77.7-85.0) | 151 (45) | NPI-Q | 55 (16.6) |
| Teng et al,31 2007 | United States | Memory clinic | MCI | Age <50 y, neurological disease, CT/MRI lesions, psychiatric/somatic disorders impairing cognition | 51 | 72.8 (7.2) | 18 (35) | NPI-i | 13 (25.5) |
| Vicini Chilovi et al,32 2009 | Italy | Memory clinic | MCI | None reported | 124 | 71.3 (7.7) | 84 (68) | Clinical | 36 (29.0) |
| Ramakers et al,24 2010 | Netherlands | Memory clinic | MCI (GDS) | Age <56 y, cerebrovascular disease, brain trauma, psychiatric/somatic disorders impairing cognition | 263 | 66.9 (7.7) | 116 (44) | HAMDb | 171 (75.0) |
| Richard et al,15 2012 | International | Database of memory clinics | MCI (C) | Depression, MMSE<24, CDR not 0.5, neurological disease, psychiatric/somatic disorders impairing cognition, unstable medical condition | 397 | 74.8 (7.5) | 141 (36) | GDS-3Ab | 178 (44.8) |
| Somme et al,33 2013 | Spain | Memory clinic | MCI | Neurodegenerative/cerebrovascular disease, acute psychiatric illness, severe comorbidities | 132 | 69.8 (8.7) | 62 (47) | NPI-i >2 | 69 (52.3) |
| Rosenberg et al,23 2013 | United States | Database of memory clinics | MCI (C) | None reported | 1821 | 75.3 (9.3) | 920 (51) | NPI-Q | 298 (16.7) |
| Sobów et al,34 2014 | Poland | Memory clinic | MCI (NAW) | CDR not equal to 0.5 | 83 | 75.0 (1.9) | 58 (70) | NPI-i | 20 (24.1) |
| Robert et al,28 2008 | France | Health clinic | aMCI (C) | Age <58 y, <4 y of education, MMSE <25, depression, MRI brain lesions | 214 | 71.8 (5.4) | 90 (42) | AI | 47 (22.0) |
| Palmer et al,36 2010 | Italy | Memory clinic | aMCI | Cerebrovascular disease, depression/somatic disorders possibly impairing cognition, MRI brain lesions |
99 | 70.5 (6.6) | 37 (37) | Clinical | 12 (12.1) |
| Peters et al,23 2013 | United States | Population based | CIND | CDR >0.5 | 230 | 81.9 (5.1) | 115 (50) | NPI-i | 21 (9.2) |
Abbreviations: AI, Apathy Inventory; aMCI, amnestic mild cognitive impairment based on revised Peterson (Mayo Clinic) criteria; AR, actively responding; BDI, Beck Depression Inventory; CD, community dwelling; CDR, Clinical Dementia Rating; CIND, cognitive impairment no dementia; CT, computed tomography; GDS-3A, Geriatric Depression Scale 3 Apathy-related subitems; GMS-AGECAT, Geriatric Mental State Automated Geriatric Examination for Computer Assisted Taxonomy; HAMD, Hamilton rating scale for depression; MCI, mild cognitive impairment based on revised Peterson (Mayo Clinic) criteria; MCI (S), based on Stephan criteria; MCI (NAW), based on National Institute on Aging-Alzheimer Association workgroup; MMSE, Mini-Mental State Examination; MRI, magnetic resonance imaging; NCI, no coginitive impairment; NP, neuropsychological; NPI-i, Neuropsychiatric Inventory for informants; NPI-Q, Neuropsychiatric Inventory Questionnaire for clinical informants; SCC, subjective cognitive concerns.
Studies ordered by publication year within diagnostic group.
Apathy measure based on subitems on a depression scale.
Only a proportion of participants 75 years and older was available.