Neuropsychological prediction of attrition due to death*

*L. J. Ritchie was aided in the manuscript preparation by a doctoral award from the Alzheimer Society of Canada Research Program. A research personnel award from the Canadian Institutes of Health Research, Institute of Aging provided support for the second author in the preparation of this manuscript. Phases 1 and 2 of the Canadian Study of Health and Aging core study were funded by the Seniors’ Independence Research Program, through Health Canada's National Health Research and Development Program [NHRDP Project 6606–3954–MC(S)]; supplementary funding for analysis of the caregiver component was provided by the Medical Research Council. Additional funding was provided by Pfizer Canada, Inc., through the Medical Research Council/Pharmaceutical Manufacturers Association of Canada Health Activity Program, NHRDP [Project 6603–1417–302(R)], by Bayer Inc., and by the British Columbia Health Research Foundation [Projects 38 (93–2) and 34 (96–1)]. Core funding for Phase 3 was obtained from the Canadian Institutes for Health Research [CIHR Grant MOP-42530]; supplementary funding for the caregiver component was obtained from CIHR Grant OP-43945. Additional funding was provided by Merck-Frosst and by Janssen-Ortho, Inc. The study was coordinated through the University of Ottawa and Health Canada.

Abstract

In aging research, attrition bias produces underestimates of cognitive decline and limits the interpretation of cognitive change. Using data from the Canadian Study of Health and Aging, we identified neuropsychological predictors of death among not cognitively impaired (NCI) and cognitively impaired, not-demented (CIND) persons. For those with NCI, two neuropsychological measures significantly predicted attrition, over and above age, in the short term, while age was the best long-term predictor. The absence of neuropsychological predictors for the CIND group may reflect the group's etiological heterogeneity. In future research, the use of a more homogeneous subset of CIND may yield additional predictors.

Notes

*L. J. Ritchie was aided in the manuscript preparation by a doctoral award from the Alzheimer Society of Canada Research Program. A research personnel award from the Canadian Institutes of Health Research, Institute of Aging provided support for the second author in the preparation of this manuscript. Phases 1 and 2 of the Canadian Study of Health and Aging core study were funded by the Seniors’ Independence Research Program, through Health Canada's National Health Research and Development Program [NHRDP Project 6606–3954–MC(S)]; supplementary funding for analysis of the caregiver component was provided by the Medical Research Council. Additional funding was provided by Pfizer Canada, Inc., through the Medical Research Council/Pharmaceutical Manufacturers Association of Canada Health Activity Program, NHRDP [Project 6603–1417–302(R)], by Bayer Inc., and by the British Columbia Health Research Foundation [Projects 38 (93–2) and 34 (96–1)]. Core funding for Phase 3 was obtained from the Canadian Institutes for Health Research [CIHR Grant MOP-42530]; supplementary funding for the caregiver component was obtained from CIHR Grant OP-43945. Additional funding was provided by Merck-Frosst and by Janssen-Ortho, Inc. The study was coordinated through the University of Ottawa and Health Canada.