Family Size may affect Cognitive Functioning Later in Life

Family Size may affect Cognitive Functioning Later in Life

A recent study from Columbia University Mailman School of Public Health, the Robert Butler Columbia Aging Center, and Université Paris-Dauphine — PSL discovered that having three or more children vs two has a deleterious influence on late-life cognition. The data also showed that this effect was largest in Northern Europe, where increasing fertility reduces financial resources but does not boost social resources. This is the first study to look into the impact of high fertility on late-life cognition.

Until far, fertility has gotten little attention as a potential predictor of late-life cognition when compared to other characteristics such as education or career. The findings were published in the journal Demography.

Cognition is crucial for functional independence as people age, including the ability to live independently, handle finances, take prescriptions appropriately, and drive safely. Furthermore, robust cognition is required for humans to communicate effectively, including processing and integrating sensory information and responding appropriately to others. Cognitive capacities frequently deteriorate as we age. It is critical to understand what types of cognitive changes are expected as part of normal aging and what types of changes may indicate the onset of brain disease.

Given the extent of the effect, future studies on late-life cognition should look at fertility as a prognosticator alongside more regularly studied predictors like education, vocational experiences, physical exercise, and mental and physical health.

Professor Vegard Skirbekk

“Understanding the factors that contribute to optimal late-life cognition is critical for ensuring successful aging at the individual and societal levels, especially in Europe, where family sizes have shrunk and populations are aging rapidly,” said Vegard Skirbekk, Ph.D., professor of population and family health at Columbia Mailman School. “Individuals’ late-life cognitive health is critical for retaining independence as well as remaining socially active and productive in old age. Ensure the cognitive health of the older population is critical for society in order to lengthen work lives while lowering health care expenses and care demands “said Eric Bonsang, Ph.D., an economics professor at Université Paris-Dauphine — PSL.

The researchers examined data from the Survey of Health, Aging, and Retirement in Europe (SHARE) to see how having three or more children compared to two children affects late-life cognition. SHARE collects data from representative samples of older people in 20 European countries and Israel, including Austria, Belgium, Croatia, the Czech Republic, Denmark, Estonia, France, Germany, Greece, Hungary, Italy, Luxembourg, the Netherlands, Poland, Portugal, Slovenia, Spain, Sweden, and Switzerland. Participants had to be at least 65 years old and have at least two biological children.

The evidence implies that having three or more children versus two children is associated with worse late-life cognition, based on advanced econometric methodologies that can untangle causation from simple relationships. They also discovered that this impact is shared by men and women.

Family size may influence cognitive functioning in later life

Fertility may influence late-life cognition through a variety of mechanisms. First, having a second child often incurs significant financial costs, reduces family income, and increases the likelihood of falling below the poverty line, lowering the standard of living for all family members and possibly causing financial worries and uncertainties, which may contribute to cognitive deterioration.

Second, having a second child is associated with decreased labor-force participation, fewer hours worked, and poorer incomes for women. In turn, labor force engagement, as opposed to retirement, improves cognitive performance in both men and women.

Third, having children reduces the chance of social isolation among older people, which is a major risk factor for cognitive impairment and dementia, and frequently increases the level of social engagement and support, which can be protective against cognitive decline in later life.

Finally, having children can be stressful, change health risk behaviors, and have a negative impact on adult cognitive development. Parents who have more children may be more stressed, have less time to relax, and may invest in cognitively challenging leisure activities. This may signal that the parent is sleep-deprived.

“Having three or more children has a significant negative impact on cognitive functioning; it is equivalent to 6.2 years of aging,” Bonsang explained. It implies that the decline in the proportion of Europeans with three or more children may have a positive impact on the cognitive health of the elderly.

“Given the extent of the effect, future studies on late-life cognition should look at fertility as a prognosticator alongside more regularly studied predictors like education, vocational experiences, physical exercise, and mental and physical health,” Skirbekk concluded. “Furthermore, future research should look into the consequences of childlessness or having only one child on late-life cognition. More research is also needed on the types of relationships, supports, and disputes that occur between parents and children, as these may influence cognitive results.”