Apathy and the risk of predementia syndromes in community-dwelling older adults

Objectives: Apathy is a potential predictor of dementia in older adults, but this investigation has been limited to older adults with a preexisting neurological illness like mild cognitive impairment (MCI), stroke or Parkinson's disease. The objective of this study was to investigate the association between apathy at baseline and incident predementia syndromes, including MCI and motoric cognitive risk syndrome (MCR), subjective cognitive complaints and slow gait, in communitydwelling older adults. Method: We prospectively studied the association between apathy (using the 3-item subscale of the Geriatric Depression Scale [GDS3A]) and incident cognitive disorders in 542 community-dwelling older adults enrolled in the Central Control of Mobility in Aging study using Cox proportional hazard models. Associations were reported as hazard ratio (HR) with 95% confidence intervals (CIs), adjusting for age, education, baseline cognitive performance, and depressive symptoms. Results: Apathy was associated with incident MCR (HR 2.39, 95% CI: 1.10-5.20), but not predementia syndromes overall nor MCI. In sensitivity analyses of MCI subtypes, apathy was associated with nonamnestic MCI (HR 2.44, 95% CI: 1.14-5.22), but not amnestic MCI. Our study was limited by a short follow-up time (median 13.6 months; interquartile range 29.8) and a brief subscale measurement of apathy, GDS3A. Discussion: In our study, apathy predicted MCR but not MCI in community-dwelling older adults. These results and the current literature suggest that apathy is an early risk factor for dementia. Additionally, apathy may be a novel treatment target that could forestall the disability of dementia.