Cognitive ability in childhood and cognitive decline in mid-life: longitudinal birth cohort study.
OBJECTIVE
To examine the association between cognitive ability in childhood and mid-life cognitive decline in the normal population.


METHODS
Longitudinal, population based, birth cohort study.


METHODS
2058 men and women born in 1946.


METHODS
Ability in childhood measured by AH4 and test of verbal comprehension at age 15 years. Ability in adulthood measured by the national adult reading test (NART) at age 53 years. Outcome measures were decline in memory (word list learning) and speed and concentration (timed visual search) from age 43 to 53 years.


RESULTS
Ability in childhood was significantly and negatively associated with decline in memory (beta = 0.09, P = 0.005, for men; 0.10, P < 0.001, for women) and search speed (beta = 0.13, P < 0.001, for men; 0.08, P = 0.01, for women), independent of educational attainment, occupational social class, and a range of health indicators. The adult reading test was also significantly and negatively associated with decline in these outcomes (for memory beta = 0.21, P < 0.001, for men; 0.17, P < 0.001, for women; and for search speed beta = -0.05 for men; 0.10, P = 0.008 for women) independent of educational attainment, social class, and childhood ability.


CONCLUSIONS
Ability in childhood can protect against cognitive decline in mid-life and beyond. Results for the adult reading test indicate that the protective effect of ability may also be acquired in adulthood.
Richards
Marcus
M
MRC National Survey of Health and Development, Department of Epidemiology and Public Health, University College London, London. m.richards@ucl.ac.uk
Shipley
Beverly
B
Fuhrer
Rebecca
R
Wadsworth
Michael E J
ME
D000293:Adolescent; D000328:Adult; D003071:Cognition; D015331:Cohort Studies; D004522:Educational Status; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008568:Memory; D008569:Memory Disorders / Q000453:epidemiology / Q000523:psychology*; D008875:Middle Aged; D012923:Social Class; D006113:United Kingdom / Q000453:epidemiology