Abstract
Cognitive decline is a significant aspect of aging, varying across domains such as executive function, working memory, and attention. Identifying modifiable risk factors and their domain-specific effects is crucial to mitigating age-related decline. Advances in online cognitive assessments facilitate large-scale studies across diverse populations, offering new opportunities for understanding cognitive aging. This analytical study utilized baseline data from 3215 participants in the PROTECT Norge cohort (aged 50+). Participants completed six cognitive tasks, alongside questionnaires on lifestyle, health, and dementia risk factors. Multivariate analyses, including exploratory factor analysis (EFA) and Independent Component Analysis (ICA), identified latent cognitive constructs. Regression models assessed the effects of aging and risk factors on cognitive performance, adjusting for demographic variables. Two latent cognitive constructs-executive function and working memory-were identified, alongside error-derived components reflecting focused attention and short-term spatial memory. Older age was associated with lower scores in all domains, with the largest effect observed for executive function [- 0.06 standard deviations (SD) per year], followed by working memory (- 0.05 SD per year), focused attention (- 0.03 SD per year), and short-term spatial memory (- 0.01 SD). Known dementia risk factors, such as stroke, smoking, and high blood pressure, significantly impaired cognitive domains, while higher education and employment provided protective effects. Moderate alcohol consumption correlated positively with cognitive outcomes, though excessive consumption had an adverse effect. The study highlights domain-specific associations between age and cognitive functions with age and the varied impact of dementia risk factors. These results highlight the value of multidimensional cognitive assessments in improving our understanding of age-related cognitive changes and the factors that influence them.