Higher early life intellectual ability is associated with better physical functioning in older age

Taina Poranen-Clark is a PhD student at University of Jyväskylä. Her special research interest is in the interrelation of cognitive and physical functioning during the life-course. She recently published Intellectual Ability in Young Adulthood as an Antecedent of Physical Functioning in Older Age in Age and Ageing journal.

Physical and cognitive functioning are important factors for maintaining functional independence and quality of life in older age. Previous studies have shown that cognitive impairment coexists with poor physical functioning and predicts changes in functional status. Cognitive ageing has implications for motor performance in older age as cognitive functions play an important role in skilled motor performance. Deterioration in the structure or function of the central nervous system has negative effects on the execution of physical tasks in old age. Executive functions are high-level cognitive functions that control and guide goal-directed motor performances. A higher level of intellectual ability in early adulthood as an antecedent of cognitive reserve is linked to better later life physical functioning.

In our study, using the Helsinki Birth Cohort Study data, we found that persons who had better intellectual ability in early adulthood had better physical functioning in older age and that the trend was maintained in the 10-year follow-up. The present findings indicate that better development of the central nervous system in early life, resulting in higher peak level of intellectual ability in early adulthood, may have far-reaching effects on cognitive reserve capacity and thus also be related to better physical functioning in older age. Persons with higher early life cognitive ability may have lower subsequent risk of cognitive impairment accompanied with decline in physical functioning.  The association with physical functioning suggests that interventions to modify individual cognitive trajectories with a view to promote cognitive reserve should be considered in future research.