Cognitive rehabilitation and cognitive training for early-stage Alzheimer's disease and vascular dementia

BACKGROUND: Memory problems are a defining feature of the early stages of Alzheimer's disease (AD) and vascular dementia. Cognitive training and cognitive rehabilitation are specific approaches designed to address everyday memory difficulties. OBJECTIVES: The main aim was to evaluate the effectiveness and impact of cognitive training and cognitive rehabilitation interventions aimed at improving memory functioning for people in the early stages of Alzheimer's disease or vascular dementia. The two types of intervention were considered separately. SEARCH STRATEGY: The CDCIG Specialized Register, which contains records from MEDLINE, EMBASE, CINAHL, PsycINFO and many other databases, was searched on 9 April 2003. SELECTION CRITERIA: RCTs comparing cognitive rehabilitation or cognitive training interventions with comparison conditions, and reporting outcomes for the person with dementia and/or the family caregiver, were considered for inclusion. DATA COLLECTION AND ANALYSIS: Six studies reporting cognitive training interventions were included. Statistical analyses were conducted to provide an indication of intervention effect sizes. Data from ordinal scales was treated as continuous, and a fixed effects model was applied in calculating weighted mean differences and 95% confidence intervals. No studies were found that reported a fully individualised cognitive rehabilitation approach. MAIN RESULTS: None of the six studies reporting cognitive training interventions demonstrated any statistically significant effects in any domain, although there were indications of some modest, non-significant effects in various domains of cognitive functioning. REVIEWER'S CONCLUSIONS: The present findings do not provide strong support for the use of cognitive training interventions for people with early-stage AD or vascular dementia, although these findings must be viewed with caution due to the limited number of RCTs available and to the methodological limitations identified, and further well-designed trials would help to provide more definitive evidence. Due to a complete absence of RCTs evaluating an individualised cognitive rehabilitation approach, It is not possible at present to draw conclusions about the efficacy of individualised cognitive rehabilitation interventions for people with early-stage dementia, and further research is required in this area.