TABLE 1.
Demographics, baseline cognitive domain z-scores, and baseline period medication-taking metrics
| Variable | Total | Incident MCI | Stable cognitively intact | P-value | Cohen’s d |
|---|---|---|---|---|---|
| N | 64 | 9 | 55 | ||
| Age at baseline (yrs) | 85.5 (6.8) | 84.4 (7.1) | 85.7 (6.8) | .59 | 0.19 |
| Sex (% female) | 77% | 89% | 75% | .67 | -- |
| Race (% white) | 97% | 89% | 98% | -- | -- |
| Education (yrs) | 15.8 (2.5) | 16.3 (2.0) | 15.8 (2.5) | .52 | 0.22 |
| MMSE (raw score) | 28.8 (1.3) | 28.4 (1.3) | 28.9 (1.3) | .38 | 0.38 |
| WRAT (raw score) | 77.4 (8.8) | 77.4 (8.5) | 77.4 (8.9) | .84 | 0.0 |
| Global Cognition (z-score) | 0.2 (0.6) | −0.5 (0.6) | 0.3 (0.6) | <.001 | 1.33 |
| Executive function (z-score) | 0.4 (0.9) | −0.4 (0.8) | 0.5 (0.9) | <.01 | 1.06 |
| Working memory (z-score) | 0.0 (1.0) | −0.8 (1.2) | 0.1 (0.9) | <.01 | .85 |
| Attention (z-score) | 0.2 (0.7) | −0.4 (0.7) | 0.3 (0.6) | <.01 | 1.07 |
| Memory (z-score) | 0.2 (0.8) | −0.5 (0.8) | 0.4 (0.7) | <.01 | 1.20 |
| Visuospatial (z-score) | 0.4 (0.8) | −0.3 (0.8) | 0.5 (0.8) | <.01 | 1.00 |
| GDS-15 (raw score) | 0.8 (1.1) | 1.4 (1.6) | 0.7 (1.0) | .09 | 0.52 |
| FAQ (raw score) | 0.3 (0.7) | 0.3 (0.7) | 0.3 (0.7) | .97 | 0.0 |
| Mean number of medications | 9.4 (4.4) | 10.1 (6.1) | 9.3 (4.1) | .66 | 0.15 |
| Mean duration of medication monitoring (years) | 2.3 (1.2) | 1.7 (0.9) | 2.4 (1.3) | .12 | 0.63 |
| Baseline period adherence (% of days with a door opening) | 85 (25) | 83 (27) | 85 (24) | .61 | 0.08 |
| Baseline period mean pill-taking time of day | 9:36 AM (3.7 hrs) | 8:32 AM (0.8 hrs) | 9:47 AM (4.0 hrs) | .82 | 0.49 |
| Baseline period variability (SD) in pill-taking time (hours) | 2.4 (1.8) | 2.6 (1.9) | 2.4 (1.8) | .64 | 0.11 |
| Time between clinical evaluation and monitoring (days) | 125 (124) | 71 (70) | 134 (129) | 0.21 | 0.61 |
Baseline period is first month (30 days) of monitoring.
We calculated each volunteers’ within-person variability (SD) in pill-taking time during the first month. Then we calculated grand means and SD for the cohort and between group comparisons.
Abbreviations: FAQ, Functional Activities Questionnaire; GDS-15, Geriatric Depression Scale-15; MCI, Mild Cognitive Impairment; MMSE, Mini-mental Status Exam; SD, standard deviation; WRAT, Wide Range Achievement Test – Reading subtest.