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Every row of the evidence table
One row per finding: what was tested, which way the result went, and how the study was built. The answer by area, and where the studies disagree, are on the main page.
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Showing 37 of 382 rows. One row per study per exposure: a study that tested two different things appears twice, once for each.
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| Exposure | Question | Direction | Outcome measured | Design | People | Effect size, as the source reported it | Source |
|---|---|---|---|---|---|---|---|
| Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Among p-tau217-positive patients, a positive eMTBR-tau243 identified clinically established Alzheimer's disease with 81% accuracy and predicted faster cognitive decline and tau accumulation. |
Classification of established Alzheimer's disease by plasma eMTBR-tau243 among %p-tau217-positive patients | cohort study | 572 | 194 (55%) of 350 %p-tau217-positive patients were also positive for eMTBR-tau243, with an accuracy of 81% (95% CI 76-84), PPV 84% (95% CI 78-88), negative predictive value (NPV) 77% (95% CI 68-82), and sensitivity 82% (95% CI 76-87) for established Alzheimer's disease, in cross-sectional analyses |
The Lancet. Neurology
2026 ✓ Peer-reviewed PMID 41864233 |
| Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. All p-tau217 tests detected abnormal amyloid PET (AUC 0.91-0.96) and tau PET (0.94-0.97); the mass-spectrometry %p-tau217 ratio was best (accuracy 0.93 versus 0.83-0.88 for immunoassays) and is proposed as a stand-alone confirmatory test, with immunoassays better suited to triage. |
Accuracy of five plasma p-tau217 tests for amyloid PET and tau PET status, benchmarked against CSF tests | cohort study | 998 | All plasma p-tau217 tests exhibited a high ability to detect abnormal Aβ-PET [area under the curve (AUC) range: 0.91-0.96] and tau-PET (AUC range: 0.94-0.97) ... For detecting Aβ-PET status, %p-tau217WashU had an accuracy of 0.93 (immunoassays: 0.83-0.88), sensitivity of 0.91 (immunoassays: 0.84-0.87) and a specificity of 0.94 (immunoassays: 0.85-0.89) |
Brain
2025 ✓ Peer-reviewed PMID 39468767 |
| Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. The ALZpath plasma p-tau217 immunoassay reached AUC 0.92-0.96 for amyloid and 0.93-0.97 for tau across three cohorts, comparable with CSF, and a three-range cut-off cut confirmatory testing by about 80%. |
Accuracy for abnormal amyloid and tau pathology (PET or CSF) and longitudinal change | cohort study | 786 | High accuracy was observed in identifying elevated Aβ (area under the curve [AUC], 0.92-0.96; 95% CI, 0.89-0.99) and tau pathology (AUC, 0.93-0.97; 95% CI, 0.84-0.99) across all cohorts. These accuracies were comparable with CSF biomarkers in determining abnormal PET signal. The detection of abnormal Aβ pathology using a 3-range reference yielded reproducible results and reduced confirmatory testing by approximately 80% |
JAMA Neurology
2024 ✓ Peer-reviewed PMID 38252443 |
| Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Plasma p-tau217 identified amyloid positivity with AUC 0.94; a two-cut-point rule sent only 17% for CSF or PET (sensitivity 0.94, specificity 0.86), and among amyloid-positive people it identified high tau load (AUC 0.92), potentially avoiding 56.9% of tau-PET scans. |
Identification of amyloid positivity and of high tau-PET load (to select candidates for anti-amyloid antibodies) | cohort study | 912 | plasma p-tau217 was most strongly associated with Aβ positivity (test-set area under the receiver operating characteristic curve [AUC] = 0.94; 95% CI, 0.90-0.97) ... This procedure had an overall sensitivity of 0.94 (95% CI, 0.90-0.98) and a specificity of 0.86 (95% CI, 0.77-0.95) ... At a false-negative rate less than 10%, the use of plasma p-tau217 could avoid 56.9% of tau-PET scans needed to identify high tau PET among Aβ-positive participants |
JAMA Neurology
2024 ✓ Peer-reviewed PMID 38048096 |
| Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. A blood model of p-tau217, age and APOE ε4 (AUC 89.3% development, 94.3% validation) used to triage patients gave 88-92% overall accuracy while cutting confirmatory CSF tests by 61-86%. |
Accuracy for amyloid PET status and reduction in confirmatory CSF tests with a two-step plasma p-tau217 workflow | cohort study | 348 | Depending on whether lenient, moderate or stringent thresholds were used in step 1, the two-step workflow overall accuracy for detecting Aβ-PET status was 88.2%, 90.5% and 92.0%, respectively, while reducing the number of necessary CSF tests by 85.9%, 72.7% and 61.2%, respectively |
Nature Aging
2023 ✓ Peer-reviewed PMID 37653254 |
| Blood biomarkers (GFAP, NfL, p-tau181) for staging and prognosis Care, carers and services | Treatment |
Benefit
whyDirection is for disclosing the blood panel during multidisciplinary meetings: median diagnostic confidence rose from 80% to 90%, though the suspected etiology changed in only 5% of patients and the syndrome diagnosis in 1%. Against CSF/PET, high- and low-probability results identified 76% of amyloid positives and 85% of negatives. |
Change in clinician diagnostic confidence and in syndrome or etiological diagnosis after disclosure of a plasma biomarker panel (p-tau181, GFAP, NfL) | cohort study | 450 | Median (IQR) diagnostic confidence in the total cohort increased from 80% (70%-90%) to 90% (70%-90%) after BBM disclosure (P < .001), increasing in 207 patients (46%), unchanged in 175 patients (39%), and decreasing in 68 patients (15%). Following BBM disclosure, syndrome diagnoses were revised in 6 patients (1%) and primary etiology was revealed in 23 patients (5%) |
JAMA Network Open
2026 ✓ Peer-reviewed PMID 42593792 |
| Blood biomarkers (GFAP, NfL, p-tau181) for staging and prognosis Care, carers and services | Treatment |
Mixed
whyThe results point different ways: diagnostic confidence rose 1.43 points, but diagnosis changed in only 17.2% and management in 27.7%, below the 30% threshold the investigators set as clinically significant; a non-elevated result reduced amyloid PET use, and patients with elevated results had higher anxiety at 2-3 months. |
Change in clinician diagnostic confidence, diagnosis and management after plasma p-tau181 testing in a memory clinic, and patient wellbeing (SUITABLE) | cohort study | 100 | Clinician diagnostic confidence averaged 1.43 points higher after p-tau181 testing (95% confidence interval [CI] 1.02 to 1.84, p < 0.0001). After testing, 27.7% (95% CI 18.9% to 36.4%, p = 0.31) of patients had a change in management and 17.2% of patients had a change in diagnosis - significantly lower than the 30% threshold (95% CI 9.5% to 24.9%, p = 0.004) |
Alzheimer's & Dementia: Translational Research & Clinical Interventions
2026 ✓ Peer-reviewed PMID 42254757 |
| Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. The two-marker plasma model matched PET-based stages with a C index of 0.91 in both the derivation and validation cohorts, tracked clinical stage (C index 0.84-0.86) and aligned with autopsy ADNC (AUC 0.96), improving on %p-tau217 alone at the intermediate stage. |
Concordance of a plasma %p-tau217 plus eMTBR-tau243 staging model with amyloid/tau PET-based biological stages, clinical stage and autopsy-confirmed AD pathology | cohort study | 1,028 | A plasma-based model with %p-tau217 and eMTBR-tau243 was derived, which demonstrated high concordance with established PET-based stages (C index, 0.91; 95% CI, 0.90-0.92) and was associated with clinical stage within the AD continuum (C index, 0.84; 95% CI, 0.82-0.86). In the validation cohort, concordance with PET-based stages was high (C index, 0.91; 95% CI, 0.87-0.94), as was concordance with clinical stage (C index, 0.86; 95% CI, 0.82-0.89) ... In the neuropathology subsample, plasma staging was strongly aligned with autopsy-confirmed AD pathology using the Alzheimer Disease Neuropathologic Change scale (area under the curve, 0.96; 95% CI, 0.91-1.00) |
JAMA Neurology
2026 ✓ Peer-reviewed PMID 42189519 |
| Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services | Treatment |
Mixed
whyThe three markers pointed different ways: plasma p-tau217 distinguished amyloid/tau stages, GFAP tracked amyloid-driven tau progression, and NfL was only weakly linked to Alzheimer pathology and, in the authors' words, inadequate as a neuronal injury biomarker for AD. |
Discrimination of amyloid/tau stages, tau progression, hippocampal atrophy and cognitive decline | cohort study | 1,275 | not established — pubmed abstract results reports no numeric estimate. the library had recorded "p-tau217 auc 0.959", which does not appear in the abstract and is not… |
Alzheimer's & Dementia
2025 ✓ Peer-reviewed PMID 41376134 |
| Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Serum GFAP tracked post-mortem tau pathology independently of amyloid, correlated negatively with brain weight and cognition, correlated with astrocyte reactivity in tissue, and separated neuropathologically confirmed AD from non-AD dementias with AUC 0.91. |
Correlation of serum GFAP with post-mortem tau pathology, brain weight and astrocyte reactivity, and discrimination of autopsy-confirmed AD from non-AD dementia | cohort study | 139 | an association between serum GFAP level and post-mortem tau pathology (β = 12.85; P < 0.001) that was independent of amyloid deposits (β = 13.23; P = 0.02) ... a negative correlation was observed between pre-mortem serum GFAP and brain weight at post-mortem (r = -0.35; P < 0.001) ... its discriminative power (area under the receiver operator characteristic curve at baseline = 0.91) in differentiating neuropathologically-confirmed Alzheimer's disease dementias from non-Alzheimer's disease dementias |
Brain
2024 ✓ Peer-reviewed PMID 38634687 |
| Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services | Treatment |
Harm
whyDirection is for higher baseline plasma GFAP: it detected abnormal CSF amyloid (AUC 0.79, 0.86 with APOE4) and predicted later conversion to Alzheimer's dementia (AUC 0.84); GFAP slopes were steeper in those who progressed. |
Detection of CSF-defined amyloid pathology and prediction of conversion to Alzheimer's dementia | cohort study | 160 | Baseline plasma GFAP could detect abnormal CSF Aβ42/40 and CSF Aβ42/T-tau with an AUC of 0.79 (95% CI 0.72-0.86) and 0.80 (95% CI 0.72-0.86), respectively. When also including APOE ε4 status as a predictor, the accuracy of the model to detect abnormal CSF Aβ42/40 status improved (AUC = 0.86, p = 0.02). Plasma GFAP predicted subsequent conversion to AD dementia with an AUC of 0.84 (95% CI 0.77-0.91) |
Alzheimer's Research & Therapy
2021 ✓ Peer-reviewed PMID 33773595 |
| CSF alpha-synuclein seed amplification assay Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Smell testing followed by CSF seed amplification only in those with reduced smell predicted brain Lewy body pathology with 94% accuracy and cut CSF testing by 43%; in a living cohort it predicted CSF assay status with 79% accuracy. |
Accuracy for autopsy-confirmed Lewy body pathology and reduction in confirmatory CSF testing | cohort study | 1,567 | Among 358 autopsied participants, the two-step workflow predicted brain LBP with high accuracy overall (94%), and within clinical subgroups (clinical parkinsonism=95%; clinical Alzheimer's disease [AD]=94%; clinically unimpaired [CU]=93%). It reduced the need for confirmatory CSF testing by 43% overall (23% clinical parkinsonism; 35% clinical AD; 80% CU). In an independent in vivo cohort (N=1209), the workflow predicted CSF α-syn SAA status with 79% accuracy and reduced CSF testing by 26% |
Nature Communications
2025 ✓ Peer-reviewed PMID 40764485 |
| Caregiving itself (exposure to the carer) Care, carers and services | Treatment |
No effect
whyNo significant difference in 5-year cumulative spending between spouses of people with and without dementia ($3,974, 95% CI -$3,199 to $11,477); year-5 spending was higher (+$2,748), driven by inpatient costs. |
Spouse's cumulative Medicare expenditures in the 5 years after the partner's dementia onset | cohort study | not stated | This difference ($3974, 95% CI = [-$3,199; $11,477]) was not significant. However, there were significant differences in the 5th year's total expenditures (+$2,748 [$321; $5,447]), driven by inpatient expenditures ($1,562 [$22; $3,277]) |
Journal of the American Geriatrics Society
2024 ✓ Peer-reviewed PMID 38975882 |
| Caregiving itself (exposure to the carer) Care, carers and services | Treatment |
Harm
whyOnly STRAINED carers were at higher risk (RR 1.63, 95% CI 1.00-2.65, with the interval touching 1). Carers who reported no strain showed nothing (RR 1.08), so it is the strain rather than the caregiving that carries the signal. |
4-year mortality in the carer | cohort study | 819 | RR 1.63 (95% CI 1.00-2.65) for strained caregivers vs. non-caregivers |
JAMA
1999 ✓ Peer-reviewed PMID 10605972 |
| Cost of dementia care Care, carers and services | Treatment |
Harm
whyDirection is for having AD dementia: lifetime formal-care costs of 2,440,000 SEK against 510,000 SEK for matched controls, with prescriptions and social care rising and specialist outpatient visits falling as the disease advanced. A cost result, not a health outcome. |
Lifetime formal-care costs after an AD dementia diagnosis versus matched controls, and care utilization by stage | cohort study | 20,366 | The estimated lifetime costs of formal care for AD dementia were 2,440,000 SEK (€212,174; $US230,189; 95% CI 2,088,000-2,793,000 SEK), compared with 510,000 SEK (€44,348; $US48,113; 95% CI 482,000-539,000 SEK) for matched controls |
PharmacoEconomics
2026 ✓ Peer-reviewed PMID 41920501 |
| Cost of dementia care Care, carers and services | Treatment |
Harm
whyDirection is for greater disease severity: mean annual costs rose from SEK 99,906 in MCI to SEK 795,617 in severe AD (SEK 57,625 to 668,073 in the amyloid-confirmed subset), driven by institutionalisation, home care and daytime support while outpatient costs fell. A cost result, not a health outcome. |
Mean annual direct medical and social costs by AD severity (MCI to severe), overall and in amyloid-confirmed patients, versus matched controls | cohort study | 95,853 | Mean annual costs for individuals with clinically diagnosed AD were SEK 99,906, SEK 290,972, SEK 479,524, and SEK 795,617 in mild cognitive impairment (MCI), mild, moderate, and severe AD. The mean annual costs for the population with both clinical diagnosis and amyloid-positive AD confirmation (N = 5610) were SEK 57,625, SEK 179,153, SEK 333,095, and SEK 668,073 in MCI, mild, moderate, and severe AD, respectively |
PharmacoEconomics
2025 ✓ Peer-reviewed PMID 39485581 |
| Cost of dementia care Care, carers and services | Treatment |
Harm
whyDirection is for being non-Hispanic Black or Hispanic rather than non-Hispanic White: disease-course Medicare spending was higher ($165,730 and $160,442 versus $136,326), highest for Black beneficiaries in every phase and driven by high-cost services in the last year of life. A disparities result, not a biological effect of race. |
Disease-course Medicare expenditures (year before diagnosis to last year of life) by race and ethnicity | cohort study | not stated | Adjusted mean total Medicare expenditures for non-Hispanic (NH) Black ($165,730) and Hispanic beneficiaries with dementia ($160,442) exceeded corresponding expenditures for NH Whites ($136,326) ... The last year of life was responsible for the greatest cost contribution: $51,294 (NH Blacks), $47,469 (Hispanics), and $39,499 (NH Whites) |
Journal of the American Geriatrics Society
2024 ✓ Peer-reviewed PMID 38504583 |
| Cost of dementia care Care, carers and services | Treatment |
Harm
whyDirection is for dying with dementia rather than heart disease, cancer or other causes: total cost was higher ($287,038) and out-of-pocket spending 81% higher, consuming 32% of household wealth versus 11%. |
Total social cost and out-of-pocket spending in the last 5 years of life | cohort study | 1,702 | Average total cost per decedent with dementia ($287 038) was significantly greater than that of those who died of heart disease ($175 136), cancer ($173 383), or other causes ($197 286) (P < 0.001). Although Medicare expenditures were similar across groups, average out-of-pocket spending for patients with dementia ($61 522) was 81% higher than that for patients without dementia ($34 068) |
Annals of Internal Medicine
2015 ✓ Peer-reviewed PMID 26502320 |
| Cost of dementia care Care, carers and services | Treatment |
Harm
whyDirection is for having dementia: the attributable yearly cost per person was $41,689-$56,290 depending on how informal care is valued, a burden the authors call similar to heart disease and cancer. |
Yearly monetary cost per person attributable to dementia, and total US cost in 2010 | cohort study | 10,903 | The yearly monetary cost per person that was attributable to dementia was either $56,290 (95% confidence interval [CI], $42,746 to $69,834) or $41,689 (95% CI, $31,017 to $52,362), depending on the method used to value informal care. These individual costs suggest that the total monetary cost of dementia in 2010 was between $157 billion and $215 billion. Medicare paid approximately $11 billion of this cost |
New England Journal of Medicine
2013 ✓ Peer-reviewed PMID 23550670 |
| Dementia care management / navigation Care, carers and services | Treatment |
Benefit
whyDirection is for the Care Ecosystem programme: total cost of care was $475.80 per member per month lower than matched controls at 12 months, with fewer emergency, outpatient and professional visits. |
Total cost of care per member per month at 12 months versus propensity-matched controls | cohort study | 242 | Care Ecosystem participants had significantly lower total cost of care at 12 months, mean savings of $475.80 per member per month compared with controls |
American Journal of Managed Care
2024 ✓ Peer-reviewed PMID 39146484 |
| Dementia screening / case finding Care, carers and services | Treatment |
Mixed
whyMCI was diagnosed sooner (HR 1.21) but dementia diagnosis barely moved (HR 1.04, 95% CI 1.02-1.06). The outcome is detection, not health. |
Timeliness of first MCI and dementia diagnosis | cohort study | 549,516 | MCI diagnosis HR 1.21 (95% CI 1.16-1.27); dementia diagnosis HR 1.04 (95% CI 1.02-1.06) after an Annual Wellness Visit |
JAMA Network Open
2024 ✓ Peer-reviewed PMID 39378037 |
| Glymphatic function (MRI DTI-ALPS index) Care, carers and services | Treatment |
Harm
whyDirection is for a lower (worse) glymphatic index: it was lowest in AD dementia and predicted faster amyloid accumulation, amyloid-positive transition, atrophy, clinical progression and cognitive decline, with the cognitive effect fully mediated by amyloid PET and atrophy. |
Amyloid PET accumulation, amyloid-positive transition, atrophy, clinical progression and cognitive decline by baseline DTI-ALPS index | cohort study | 419 | not established — pubmed abstract reports no numeric effect size. |
Alzheimer's & Dementia
2024 ✓ Peer-reviewed PMID 38501315 |
| Health-system and payment model Care, carers and services | Treatment |
No effect
whyDifference-in-differences around ACO entry found no change in end-of-life care processes, outcomes or spending. |
Hospice use and end-of-life spending | cohort study | 162,034 | Hospice use difference -0.4 percentage points (95% CI -1.4 to 0.5); last-6-months spending -$632 (95% CI -$1,377 to $113) |
JAMA Health Forum
2025 ✓ Peer-reviewed PMID 40343716 |
| Health-system and payment model Care, carers and services | Treatment |
No direction reported
whyA single-programme implementation report with no comparison group. It counts enrolment and service use and estimates no effect. |
Enrolment, respite use and disenrolment in the first year of one GUIDE programme | cohort study | 158 | Over 35% of eligible beneficiaries have utilized respite services. Approximately 9% have disenrolled, the majority (64%) expired/hospice |
Innovation in Aging (GSA 2025 conference abstract)
2025 ⚠ Conference abstract — not peer-reviewed DOI 10.1093/geroni/igaf122.3561 |
| Hospital admission after an emergency department visit Care, carers and services | Treatment |
Mixed
whyAdmission showed no evidence of an effect on 30-day mortality or subsequent inpatient days, but raised 30-day health care spending by $2547. An instrumental-variable estimate for marginal admissions. |
30- and 90-day mortality, inpatient days and health care spending after hospital admission versus discharge | cohort study | 872,085 | There was no evidence that hospital admission was associated with 30-day mortality rate (adjusted risk difference, -2.6 percentage points [pp] [95% CI, -5.2 to 0.1 pp]) or inpatient days (adjusted difference, 0.1 days [CI, -0.2 to 0.5 days]). Hospital admission was associated with higher 30-day health care spending (adjusted difference, $2547 [CI, $1390 to $3703]) |
Annals of internal medicine
2026 ✓ Peer-reviewed PMID 42258826 |
| Lewy body co-pathology (CSF seed amplification) Care, carers and services | Treatment |
Harm
whyDirection is for co-existing Lewy body pathology in people with Alzheimer pathology: worse baseline cognition, faster global cognitive decline and more posterior hypometabolism than Alzheimer pathology alone. The seed amplification assay itself agreed closely with autopsy (96.3% sensitivity, 96.4% specificity in 61 cases). |
Baseline cognition, rate of global cognitive decline and cortical hypometabolism in people with Alzheimer pathology | cohort study | 795 | 184 (23.1%) had no biomarker evidence of AD/LB pathology, 39 (4.9%) had isolated LB pathology (AD-LB+), 395 (49.7%) had only AD pathology (AD+LB-), and 177 (22.3%) had both pathologies (AD+LB+) ... Neuropathological examination (n = 61) showed high sensitivity (26/27, 96.3%) and specificity (27/28, 96.4%) of the SAA-test |
Nature Communications
2024 ✓ Peer-reviewed PMID 39277604 |
| MRI amygdalar atrophy scale (marker of LATE) Care, carers and services | Treatment |
No direction reported
whyA classification-validation study without a neuropathological reference standard, so accuracy cannot be judged. The groups behaved as expected: patients labelled LATE had mild amnestic impairment, limbic atrophy and stable MMSE over 30 months, while AD and AD/LATE groups declined. |
Clinical, imaging and 30-month cognitive profiles of memory-clinic patients classified as LATE, AD, AD/LATE or neither by the amygdalar atrophy scale plus AD biomarkers | cohort study | 469 | the LATE group maintained cognitive stability as the No-AD/No-LATE group (β = -0.010, 95% CI -0.096 to 0.075, p = 0.813), whereas both AD (β = -0.136, 95% CI -0.184 to -0.088, p < 0.001) and AD/LATE (β = -0.139, 95% CI -0.196 to -0.082, p < 0.001) groups showed faster decline over time |
Neurology
2026 ✓ Peer-reviewed PMID 41428981 |
| Naturalistic driving behaviour (digital marker of MCI) Care, carers and services | Treatment |
Benefit
whyDirection is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Driving features distinguished drivers with MCI from those with normal cognition (AUC 0.82), rising to 0.87 with demographics, APOE4 and cognition; drivers with MCI showed greater declines in trip frequency, night driving and route variety. |
Discrimination of MCI from normal cognition by daily driving features, and longitudinal change in driving | cohort study | 298 | Key features such as medium trip distance, speeding events, entropy, and maximum distance distinguished drivers with MCI from those with NC (area under the curve [AUC] 0.82, 95% CI 0.75-0.89). Adding demographics, APOE ε4, and cognitive composite improved AUC to 0.87 (95% CI 0.81-0.93) |
Neurology
2025 ✓ Peer-reviewed PMID 41296993 |
| Tau PET imaging (natural history of tau) Care, carers and services | Treatment |
Harm
whyDirection is for amyloid: it induced hyperconnectivity from tau epicentres to posterior tau-vulnerable regions, present already in preclinical AD, and this hyperconnectivity mediated amyloid's effect on faster tau accumulation. |
Amyloid-related functional hyperconnectivity of temporal-lobe tau epicentres, and its mediation of amyloid's effect on longitudinal tau accumulation | cohort study | 609 | not established — pubmed abstract reports no numeric effect size. |
Science Translational Medicine
2025 ✓ Peer-reviewed PMID 39841807 |
| Tau PET imaging (natural history of tau) Care, carers and services | Treatment |
Harm
whyDirection is for greater spatial extent of tau: it tracked memory in unimpaired people and executive function in MCI and dementia better than a temporal meta-ROI, and tau spread fastest in unimpaired and MCI participants. Most amyloid-positive participants followed Braak staging, with substantial regional heterogeneity within each stage. |
Spatial extent of abnormal tau over time and its association with cognition | cohort study | 832 | More than 80% of amyloid-beta positive participants across diagnostic groups followed typical Braak staging, both cross-sectionally and longitudinally. Within each Braak stage, however, the pattern of abnormality demonstrated significant heterogeneity such that the overlap of abnormal regions across participants averaged less than 50% ... Accumulation of tau progressed more rapidly among cognitively unimpaired and participants with mild cognitive impairment (1.2 newly abnormal regions per year) compared to participants with Alzheimer's disease dementia (less than 1 newly abnormal region per year) |
Brain Communications
2024 ✓ Peer-reviewed PMID 38410618 |
| Undiagnosed or delayed diagnosis Care, carers and services | Treatment |
Harm
whyDirection is for going undiagnosed. Whether the diagnosis itself would change survival is not tested here. |
4-year mortality | cohort study | 13,142 | 45.1% (US) and 76.1% (Brazil) of dementia cases undiagnosed; the abstract states undiagnosed dementia was associated with increased 4-year mortality compared with no dementia in both countries, without giving a hazard ratio |
Alzheimer's & Dementia
2026 ✓ Peer-reviewed PMID 42056069 |
| Anti-amyloid antibody Medicines | Treatment |
No direction reported
whyA single-clinic safety series with no comparison group. It reports how often ARIA and infusion reactions happened in practice, which is useful, but it cannot estimate an effect of the drug in either direction. |
ARIA and infusion reactions in routine care | cohort study | 234 | ARIA 22%; symptomatic ARIA 5.7% overall, 27% in mild dementia vs 1.8% in MCI/very mild dementia |
JAMA Neurology
2025 ✓ Peer-reviewed PMID 40354064 |
| Antipsychotics (harms / discontinuation) Medicines | Treatment |
Benefit
whyDirection is for STOPPING the antipsychotic: discontinuers were hospitalised less than matched continuers. |
Hospitalisation, pneumonia and urinary tract infection | cohort study | 4,222 | All-cause hospitalisation HR 0.83 (95% CI 0.72-0.96); pneumonia hospitalisation HR 0.51 (0.29-0.90) |
Alzheimer's Research & Therapy
2026 ✓ Peer-reviewed PMID 42410659 |
| Antipsychotics (harms / discontinuation) Medicines | Treatment |
Benefit
whyDirection is for discontinuation: tapering after 12 weeks lowered the 24-month absolute risk of delirium and fracture versus continuing, with no difference in stroke, pneumonia or death. Results were similar for abrupt discontinuation and after 24 weeks. |
24-month risk of delirium, fracture, stroke, pneumonia and death after tapering or stopping antipsychotics versus continuing | cohort study | 24,822 | Compared with continuation after 12 weeks of treatment, estimated risks of delirium and fracture under the tapering strategy corresponded to 24-month ARDs of -2·46% (95% CI -4·10 to -1·27) and -2·80% (-4·14 to -1·29), respectively. Estimated risks for stroke, pneumonia, and all-cause mortality were similar between strategies |
The lancet. Healthy longevity
2026 ✓ Peer-reviewed PMID 42302797 |
| Antipsychotics (harms / discontinuation) Medicines | Treatment |
Harm
whyWider range of harms than regulatory alerts had flagged, with the highest risks soon after starting. No increase in ventricular arrhythmia. |
Stroke, pneumonia, venous thromboembolism, MI, heart failure, fracture, acute kidney injury | cohort study | 173,910 | Pneumonia HR 2.19 (95% CI 2.10-2.28); stroke HR 1.61 (1.52-1.71); absolute 90-day pneumonia risk difference 2.99% |
BMJ
2024 ✓ Peer-reviewed PMID 38631737 |
| Cholinesterase inhibitor / memantine Medicines | Treatment |
Benefit
whyObservational: 80% of residents were on no anti-dementia drug, so who gets prescribed and who does not may itself track prognosis. |
All-cause mortality | cohort study | 25,358 | Adjusted hazard ratios for mortality vs no anti-dementia drug: "HR: 0.826, 95%CI 0.769 to 0.888 for AChEI; 0.857, 95%CI 0.795 to 0.923 for memantine; 0.742, 95%CI 0.640 to 0.861 for AChEI plus memantine" |
Alzheimer's Research & Therapy
2024 ✓ Peer-reviewed PMID 38812028 |
| Cholinesterase inhibitor / memantine Medicines | Treatment |
Benefit
whyCholinesterase inhibitors, not memantine: -0.39 MMSE points a year against -2.50 with no treatment. The mortality benefit held only in the first year. Registry data with weighting, not a trial. |
MMSE decline per year; mortality | cohort study | 1,095 | MMSE change: -0.39 points/year (95% CI -0.96 to 0.18) with cholinesterase inhibitors vs -2.49 (-4.02 to -0.97) with memantine and -2.50 (-4.28 to -0.73) with non-use. Mortality in the first year after diagnosis: adjusted HR 0.66 (95% CI 0.46 to 0.94) |
Alzheimer's & Dementia
2024 ✓ Peer-reviewed PMID 39177108 |