Correlates of personality trait levels and their changes in very old age: The Lothian Birth Cohort 1921

We tested the associations between individual differences in the Big Five personality traits and their changes over the ninth decade of life and levels of and changes in cognitive functioning, physical fitness, and everyday functioning. Besides mean-level changes in personality traits, there were significant individual differences in their rates of change between ages 81 and 87. The changes in the Big Five traits were not strongly intercorrelated, suggesting little common influence on personality change. Lower IQ at age 79 predicted lower Intellect and higher Extraversion, and more decline in Conscientiousness from ages 81 to 87. Also, decreases in physical fitness were associated with declines in Conscientiousness.

► There were significant individual differences in personality trait change in the ninth life decade.
► Individuals’ change trajectories in different personality traits were not correlated.
► High IQ at age 79 predicted less decline in Conscientiousness in the next decade.
► Declines in Conscientiousness and physical fitness were correlated.