Trajectories of immediate and delayed verbal memory in the Spanish general population of middle-aged and older adults

Abstract

(1) Cognitive decline differs among individuals and cognition function domains. We sought to identify distinct groups of immediate and delayed verbal memory in two age subsamples(50–64, 65+years), and to analyze associated factors. (2) Latent class mixed models were used to identify verbal memory trajectories in a sample of Spanish community-dwelling individuals over 8 years' follow up. Chi-square and Kruskal–Wallis tests were used to assess differences among trajectories. (3) Different trajectories were identified. In the case of immediate verbal memory, these were: very low/decline (6.3%), low/stable (38.2%), medium/slow decline (43.4%), and high/slowdecline (12.2%) in the middle-aged group, and low/decline (20.4%), medium/slow decline (60.4%),and high/slow decline (19.2%) in the older subsample. In delayed verbal memory, more distinct patterns were found: very low/decline (12.4%), low/stable (51.4%), medium/accelerated decline (24.7%),and high/slow increase (11.4%) in the younger group, and low/slow decline (34.4%), medium/decline(52.7%), and high/slow decline (12.9%) in the older group. (4) Overall, low initial performance and decline were associated with older age, lower education, and higher diabetes/stroke prevalence.Differences found suggests heterogeneity in cognitive ageing. The high prevalence of cardiovascular diseases in those with worse cognition suggests that early interventions to prevent those conditions should be targeted in midlife to delay cognitive decline. ; This work was supported by the European Community's Seventh Framework Programme [grant number223071-COURAGE Study]; the Instituto de Salud Carlos III-FIS [grant numbers PS09/00295, PS09/01845, PI12/01490,and PI13/00059. Projects PI12/01490 and PI13/00059 have been co-funded by the European Union EuropeanRegional Development Fund (ERDF) "A Way to Build Europe"]; the European Union's Horizon 2020 Research andInnovation Programme [grant agreement 635316]; and the Centro de Investigación Biomédica en Red de SaludMental (CIBERSAM), Instituto de Salud Carlos III. NMM is supported by the programme 'Contratos predoctoralespara Formación de Personal Investigador, FPI-UAM', Universidad Autónoma de Madrid, Spain. EL's work issupported by the Sara Borrell postdoctoral program (CD18/00099) of the Instituto de Salud Carlos III (Spain)and co-funded by the European Union (ERDF/ESF, "Investing in your future"). DM's work is supported by theSpanish Ministry of Education, Culture, and Sports [grant number FPU15/02634]. DF's work has been supportedby grant RTI2018-100927-J-I00 administrated by Ministerio de Ciencia e Innovación (MCI, Spain), by the AgenciaEstatal de Investigación (AEI, Spain), and by the European Regional Development Fund (FEDER, UE), by Marsdengrant E2987-3648 administrated by the Royal Society of New Zealand), and by grant 2017 SGR 622 (GRBIO)administrated by the Departament d'Economia i Coneixement de la Generalitat de Catalunya (Spa ; Peer Reviewed ; Postprint (published version)