# Mid‐life cardiorespiratory fitness and risk of late‐onset dementia incidence

## TL;DR

Higher cardiorespiratory fitness in mid-life is linked to a lower risk of developing dementia later in life, especially for people under 55 with medium education.

## Contribution

This study identifies education level as a key moderating factor in the relationship between mid-life CRF and dementia risk.

## Key findings

- High CRF is associated with a 42% lower dementia risk in individuals under 55 and a 25% lower risk in those over 55.
- Medium education levels moderate the CRF-dementia risk relationship in individuals under 55.
- Sex and civil status do not influence the CRF-dementia risk association.

## Abstract

Cardiorespiratory fitness (CRF) is linked to dementia risk, but moderating factors remain unclear. This study examined how and when CRF in adulthood is associated with late‐onset dementia (> 65 years) and whether sex, civil status, or education moderate this association.

In a cohort of 370,980 dementia‐free individuals followed for a mean of 11.9 (standard deviation 6.0) years, CRF was estimated via a submaximal cycle test, with dementia incidence obtained from Swedish National Healthcare Registries.

Results showed that high CRF was associated with lower dementia risk in those under age 55 (hazard ratio [HR]: 0.58, 95% confidence interval [CI] 0.36–0.92) and those > 55 (HR: 0.75, 95% CI 0.63–0.89) at CRF assessment. Medium education levels moderate the association in individuals < 55 years.

These findings underscore the role of maintaining a high CRF in dementia prevention, emphasizing education level as a critical moderating factor.

High cardiorespiratory fitness (CRF) is longitudinally associated with a lower risk of late‐onset dementia.The association was evident in those both under and over age 55 at CRF assessment.Higher education levels moderated the relationship in those < 55 years.Sex and civil status did not moderate the association.

High cardiorespiratory fitness (CRF) is longitudinally associated with a lower risk of late‐onset dementia.

The association was evident in those both under and over age 55 at CRF assessment.

Higher education levels moderated the relationship in those < 55 years.

Sex and civil status did not moderate the association.