Persistent functional impairment as an early indicator of cognitive decline and dementia in cognitively normal older adults
Bibliographic record
Abstract
Background Functional independence is crucial for healthy aging, and its loss is a diagnostic criterion for dementia, including Alzheimer's disease. However, functional impairment (FI) can emerge before dementia diagnosis. Early and accurate characterization of FI may help identify individuals at elevated risk of cognitive decline and dementia. Objective Exploring the utility of capturing persistent versus impersistent FI, to identify a higher-risk group for incident cognitive decline and dementia. Method Data from 11,793 cognitively normal (CN) older adults from the National Alzheimer's Coordinating Center were analyzed. Exploratory factor analysis identified four Functional Activities Questionnaire items—preparing hot drinks, preparing balanced meals, shopping, and traveling—representing primarily functional abilities. An FI composite score was calculated as the sum of these items. Persistent FI was operationalized as FI present (composite score ≥ 2) at more than two-thirds of all visits prior to cognitive decline and dementia. Comparator groups were impersistent/transient FI and no FI. Time-dependent covariate Cox models compared incidence of cognitive decline and dementia across time-dependent FI groups, adjusted for demographics, APOE ε4 status, presence of neuropsychiatric symptoms, CDR sum of boxes, and informant characteristics (age, sex, relationship, cohabitation status). Results The CN sample comprised 164 Persistent-FI (age = 75.7 ± 12.2; 59.1% female), 522 Transient-FI (age = 73.7 ± 9.5; 62.8% female), and 11,107 No-FI participants (age = 70.9 ± 8.9; 66.0% female). Persistent-FI was associated with a 2.12-fold greater incidence of cognitive decline and dementia versus No-FI (CI:1.80–2.51, p < 0.001). Transient-FI showed no significant difference (HR = 1.14, CI:0.97–1.33, p = 0.107). Conclusions Operationalizing FI-related risk based on persistence is a promising approach to incorporation of FI into dementia prognostication.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".