1 University of Saskatchewan, College of Medicine, Department of Surgery, Canada. Electronic address: paul.mick@usask.ca.
2 Saskatchewan Health Authority, Canada.
3 University of Alberta, College of Health Sciences, Department of Ophthalmology and Visual Sciences, Canada.
4 Professor emeritus, University of Toronto, Faculty of Arts and Sciencies, Department of Psychology, Canada.
5 Memorial University of Newfoundland, Faculty of Medicine, Canada.
6 McGill University, Faculty of Medicine and Health Sciences, Department of Human Genetics, Canada.
7 Université de Montréal, École d'optométrie, Canada.
8 Concordia University, Faculty of Arts and Sciences, Department of Psychology, Canada.

Introduction: Hearing loss and diminished visual acuity are associated with poorer cognition, but the underlying mechanisms are not understood. The apolipoprotein (APOE) e4 allelic variant may drive the associations. We tested whether APOE-e4 allele count (0, 1, or 2) was associated with declines in memory, executive function, pure-tone hearing threshold averages, and pinhole-corrected visual acuity among participants in the Canadian Longitudinal Study on Aging (CLSA).

Methods: Multivariable linear mixed regression models were utilized to assess associations between APOE-e4 allele count and each of the outcome variables. For each main effects model, interactions between APOE-e4 and sex and age group (45-54-, 55-64-, 65-74-, and 75-85 years) respectively, were analyzed.

Results: Significant associations were not observed in main effects models. Models including APOE-e4 * age (but not APOE-e4 * sex) interaction terms better fit the data compared to main effects models. In age group-stratified models, however, there were minimal differences in effect estimates according to allele count.

Conclusion: APOE-e4 allele count does not appear to be a common cause of sensory-cognitive associations in this large cohort.