Studies assessing other predictors of cognitive improvement with acetylcholinesterase inhibitor therapy for Alzheimer’s disease
| Study | Sample | Design | Predictor evaluated | Drug | Responder definition | Results |
|---|---|---|---|---|---|---|
| Pretreatment postural blood pressure drop | ||||||
| Schneider et al (48) | n = 40, mild-tomoderate AD | Double-blind, placebocontrolled trial | Difference between supine and standing systolic BP 2 min after standing | Tacrine | ADAS-cog at end of 2 wk | Advantage: larger fall in BP |
| Pomara et al (49) | n = 23 | 5-wk double-blind | Difference between supine and sitting BP 2 min after sitting up | Velnacrine | ADAS-cog after 5 wk | Advantage: smaller fall in BP |
| Change in qEEG after test dose | ||||||
| Alhainen et al (53) | n = 14 | 4-wk open-label trial | Alpha-theta ratio after test dose of tacrine | Tacrine | MMSE after 4 wk | Advantage: higher alpha-theta ratio |
| Alhainen and Riekkinen (54) | n = 14, mild-tomoderate AD | 7-wk open-label trial | Alpha-theta ratio after test dose of tacrine | Tacrine | MMSE after 7 wk | Advantage: higher alpha-theta ratio |
| Knott et al (55) | n = 24, mild-tomoderate AD | 12-wk open-label trial | Mean alpha frequency at baseline, relative theta power after a single tacrine dose, responders v. nonresponders | Tacrine | Post-hoc analysis of MMSE at 12 wk | Advantage: faster baseline mean alpha frequency Advantage: reduction in relative theta (after a single test dose) |
| Almkvist et al (39) | n = 24, mild-tomoderate AD | Double-blind randomized placebo-controlled trial of single-dose administration | Alpha-theta ratio | Tacrine | Measures of attention after a single dose | Advantage: higher frontal alpha-theta ratio (single-dose responders). Response to a single dose not significantly correlated to long-term treatment outcome |
| Disease progression rate | ||||||
| Farlow et al (57) | n = 235 doubleblind n = 187 openlabel extension | 26-wk double-blind, randomized placebocontrolled trial and 26-wk open-label extension | Disease progression rate | Rivastigmine | ADAS-Cog after 26 wk of open-label trial | Advantage: rapidly progressive AD |
| Hanyu et al (60) | n = 72 consecutive outpatients with mild-to-moderate AD | 14- to 18-wk open-label 3 mg OD × 2 wk, then 5 mg OD for 12–16 additional wk | Thickness of the substantia innominata on the plane through the anterior commissure (MRI) | Donepezil | MMSE after 14–18 wk of open-label trial | Advantage: greater atrophy in the substantia innominata |
| Response to test dose | ||||||
| Alhainen and Riekkinen (54) | n = 14, mild-tomoderate AD | 7-wk treatment with tacrine | Neuropsychological testing after a single dose of tacrine | Tacrine | MMSE after tacrine treatment | Might be useful in discriminating responders to longer-term treatment |
Note: BP = blood pressure; OD = once daily. See Table 1 footnote for explanation of other abbreviations.