Effects of a newly developed cognitive intervention in amnestic mild cognitive impairment and mild Alzheimer's disease: a pilot study

Abstract

Recent studies have shown that patients with Alzheimer's disease (AD) and its possible prodromal stage mild cognitive impairment benefit from cognitive interventions. Few studies so far have used an active control condition and determined effects in different stages of disease. We evaluated a newly developed 6-month group-based multicomponent cognitive intervention in a randomized controlled pilot study on subjects with amnestic mild cognitive impairment (aMCI) and mild AD patients. Forty-three subjects with aMCI and mild AD were recruited. Primary outcome measures were change in global cognitive function as determined by the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) and the Mini Mental Status Examination (MMSE). Secondary outcomes were specific cognitive and psychopathological ratings. Thirty-nine patients were randomized to intervention groups (IGs: 12 aMCI, 8 AD) and active control groups (CGs: 12 aMCI, 7 AD). At the end of the study, we found significant improvements in the IG(MCI) compared to the CG(MCI) in the ADAS-cog (p = 0.02) and for the secondary endpoint Montgomery Asberg Depression Rating Scale (MADRS) (p < 0.01) Effects on the MMSE score showed a non-significant trend (p = 0.07). In AD patients, we found no significant effect of intervention on the primary outcome measures. In conclusion, these results suggest that participation in a 6-month cognitive intervention can improve cognitive and non-cognitive functions in aMCI subjects. In contrast, AD patients showed no significant benefit from intervention. The findings in this small sample support the use of the intervention in larger scales studies with an extended follow-up period to determine long-term effects.