Table 3.
Factors affecting the long-term outcome with MMSE or ADAS-cog score as dependent variables
| MMSE | ADAS-cog | |||||
|---|---|---|---|---|---|---|
| Percentage of variance accounted for, all fixed terms | 53.7%, P < 0.001 | 57.8%, P < 0.001 | ||||
| Significant predictors in final mixed models | β | 95% CI (β) | P-value | β | 95% CI (β) | P-value |
| Fixed terms | ||||||
| Intercept | -25.766 | -36.047, -15.484 | < 0.001 | -8.756 | -19.030, 1.518 | 0.095 |
| Time in months from baseline | -0.507 | -0.605, -0.409 | < 0.001 | -0.211 | -0.381, -0.040 | 0.016 |
| MMSE (ADAS-cog) baseline score | 2.666 | 2.074, 3.259 | < 0.001 | 1.604 | 1.157, 2.051 | < 0.001 |
| MMSE (ADAS-cog) baseline score2 | -0.018 | -0.028, -0.008 | < 0.001 | ns | ||
| Time in months × MMSE (ADAS-cog) baseline score | 0.023 | 0.019, 0.027 | < 0.001 | 0.016 | 0.011, 0.021 | < 0.001 |
| Time in months2 × MMSE (ADAS-cog) baseline score | -0.0001 | -0.0001, -0.0001 | < 0.001 | 0.0001 | 0.00004, 0.0002 | 0.004 |
| Background variables: | ||||||
| Gender (male = 0, female = 1) | -0.395 | -0.718, -0.072 | 0.017 | -1.290 | -3.262, 0.681 | 0.199 |
| MMSE (ADAS-cog) baseline score × Gender | ns | 0.110 | 0.020, 0.199 | 0.016 | ||
| APOE ε4 carrier (no = 0, yes = 1) | ns | 1.072 | 0.239, 1.906 | 0.012 | ||
| NSAIDs/Acetylsalicylic acid (no = 0, yes = 1) | 0.440 | 0.094, 0.785 | 0.013 | -1.037 | -1.890, -0.184 | 0.017 |
| Education, years | 0.085 | 0.017, 0.153 | 0.014 | -0.147 | -0.339, 0.044 | 0.131 |
| Time in months × Education, years | -0.013 | -0.019, -0.007 | < 0.001 | 0.018 | 0.003, 0.033 | 0.016 |
| Age at first assessment, years | 0.361 | 0.237, 0.485 | < 0.001 | 0.168 | 0.036, 0.300 | 0.013 |
| MMSE (ADAS-cog) baseline score × Age | -0.017 | -0.023, -0.011 | < 0.001 | -0.012 | -0.018, -0.006 | < 0.001 |
| IADL score at baseline | -0.090 | -0.124, -0.056 | < 0.001 | 0.256 | 0.170, 0.343 | < 0.001 |
| ChEI-dosea | 0.010 | 0.001, 0.018 | 0.024 | -0.040 | -0.062, -0.019 | < 0.001 |
| Random terms (variance) | ||||||
| Intercept | 2.613 | 2.166, 3.153 | < 0.001 | 13.887 | 10.274, 18.770 | < 0.001 |
| Time in months | 0.027 | 0.023, 0.032 | < 0.001 | 0.131 | 0.108, 0.158 | < 0.001 |
Solitary living, concomitant medications with the exception of NSAIDs/Acetylsalicylic acid, age at onset, basic ADL ability, change of dosage and the variable comparing the ChEI agents were not significant.
β values were unstandardized and are expressed per one unit increase for continuous variables and for the condition present in dichotomous variables.
aMean percentage of the maximum recommended dose, that is, 10 mg donepezil, 12 mg rivastigmine and 24 mg galantamine.
Abbreviations: ADAS-cog, Alzheimer's Disease Assessment Scale-cognitive subscale; APOE, Apolipoprotein E; ChEI, Cholinesterase inhibitors; CI, Confidence interval; IADL, Instrumental Activities of Daily Living scale; MMSE, Mini-Mental State Examination; NSAID, Nonsteroidal anti-inflammatory drugs; ns, not significant.