Robert Fieo1, Yaakov Stern2. 1. Center for Cognitive Aging and Memory, Department of Geriatric Research, College of Medicine, University of Florida, Gainesville, Florida, USA. 2. Cognitive Neuroscience Division, Department of Neurology and Taub Institute, Columbia University College of Physicians and Surgeons, New York, New York, USA.
Abstract
BACKGROUND/AIMS: Dementia exhibits an insidious onset consisting of cognitive, behavioral, and functional impairment. We explored a functional continuum that extends assessment beyond the clinical instrumental activities of daily living (IADL) range and into advanced activities of daily living. METHODS: We examined the predictive power (Cox regression; n = 2,471) of a unidimensional IADL-extended (IADL-x) scale for incident mild cognitive impairment (MCI). We also examined "time to MCI" as an outcome measure. RESULTS: Each additional task endorsed on the IADL-x hierarchy (e.g., endorsing participation in 6 vs. 5 activities) resulted in a 10% reduction in MCI risk (HR 0.90, 95% CI 0.85-0.94, p < 0.001). For the fully adjusted model the risk reduction dropped to 6%. The odds of incident MCI within 2 years (for those below the median IADL-x total score) was 2.5 times higher (OR 2.60, 95% CI 1.52-4.4, p < 0.001) and 2 times higher for incident MCI within the next 5 years (OR 1.93, 95% CI 1.76-3.2, p < 0.01). CONCLUSION: The IADL-x metric appears to be a valid approach for determining the risk of MCI based on one's position along a formal hierarchy of function.
BACKGROUND/AIMS: Dementia exhibits an insidious onset consisting of cognitive, behavioral, and functional impairment. We explored a functional continuum that extends assessment beyond the clinical instrumental activities of daily living (IADL) range and into advanced activities of daily living. METHODS: We examined the predictive power (Cox regression; n = 2,471) of a unidimensional IADL-extended (IADL-x) scale for incident mild cognitive impairment (MCI). We also examined "time to MCI" as an outcome measure. RESULTS: Each additional task endorsed on the IADL-x hierarchy (e.g., endorsing participation in 6 vs. 5 activities) resulted in a 10% reduction in MCI risk (HR 0.90, 95% CI 0.85-0.94, p < 0.001). For the fully adjusted model the risk reduction dropped to 6%. The odds of incident MCI within 2 years (for those below the median IADL-x total score) was 2.5 times higher (OR 2.60, 95% CI 1.52-4.4, p < 0.001) and 2 times higher for incident MCI within the next 5 years (OR 1.93, 95% CI 1.76-3.2, p < 0.01). CONCLUSION: The IADL-x metric appears to be a valid approach for determining the risk of MCI based on one's position along a formal hierarchy of function.