Gender Selectively Mediates the Association Between Sex and Memory in Cognitively Normal Older Adults

Sex and gender are important topics of increasing interest in aging and dementia research. Few studies have jointly examined sex (as a biological attribute) and gender (as a sociocultural and behavioral characteristic) within a single study. We explored a novel data mining approach to include both sex and gender as potentially related influences in memory aging research.

Participants were 746 cognitively normal older adults from the Victoria Longitudinal Study. First, we adapted the Gender Outcomes INternational Group: To Further Well-being Development (GOING-FWD) framework-which is informed by gender dimensions of the Women's Health Research Network-to identify, extract, and operationalize gender-related variables in the database. Second, we applied principal component analysis (PCA) to a pool of potential gender variables for creating empirically derived gender-related components. Third, we verified the expected pattern of sex differences in memory performance and evaluated each gender-related component as a potential mediator of the observed sex-memory association.

Systematic data mining produced a roster of potential gender-related variables, 56 of which corresponded to gender dimensions represented in the GOING-FWD framework. The PCA revealed 6 gender-related components (n indicators = 37): Manual Non-Routine Household Tasks, Subjective Memory Beliefs, Leisure Free Time, Social and Routine Household Management, Health Perceptions and Practices, and Brain Games. We observed sex differences in latent memory performance whereby females outperformed males. Sex differences in memory performance were mediated by Manual Non-Routine Household Tasks, Social and Routine Household Management, and Brain Games. Follow-up analyses showed that education also mediated the sex-memory association.

We show that (i) data mining can identify and operationalize gender-related variables in archival aging and dementia databases, (ii) these variables can be examined for associations with sex, and (iii) sex differences in memory performance are mediated by selected facets of gender.