TY - JOUR
T1 - Intelligence Test Scores Before and After Alcohol-Related Disorders—A Longitudinal Study of Danish Male Conscripts
AU - Grønkjær, Marie
AU - Flensborg-Madsen, Trine
AU - Osler, Merete
AU - Sørensen, Holger Jelling
AU - Becker, Ulrik
AU - Mortensen, Erik Lykke
PY - 2019/10/1
Y1 - 2019/10/1
N2 - Background: Existing studies on intellectual consequences of alcohol-related disorders are primarily cross-sectional and compare intelligence test scores of individuals with and without alcohol-related disorders, hence mixing the influence of alcohol-related disorders and predisposing factors such as premorbid intelligence. In this large-scale study, the primary aim was to estimate associations of alcohol-related disorders with changes in intelligence test scores from early adulthood to late midlife. Methods: Data were drawn from a follow-up study on middle-aged men, which included a re-examination of the same intelligence test as completed in young adulthood at military conscription (total analytic sample = 2,499). Alcohol-related hospital diagnoses were obtained from national health registries, whereas treatment for alcohol problems was self-reported at follow-up. The analyses included adjustment for year of birth, retest interval, baseline intelligence quotient (IQ) score, education, smoking, alcohol consumption, and psychiatric and somatic comorbidity. Results: Individuals with alcohol-related hospital diagnoses (8%) had a significantly lower baseline IQ score (95.0 vs. 100.5, p ' 0.001) and a larger decline in IQ scores from baseline to follow-up (−8.5 vs. −4.8, p ' 0.001) than individuals without such diagnoses. The larger decline in IQ scores with alcohol-related hospital diagnoses remained statistically significant after adjustment for all the covariates. Similar results were revealed when IQ scores before and after self-reported treatment for alcohol problems (10%) were examined. Conclusions: Individuals with alcohol-related disorders have a lower intelligence test score both in young adulthood and in late midlife, and these disorders, moreover, seem to be associated with more age-related decline in intelligence test scores. Thus, low mean intellectual ability observed in individuals with alcohol-related disorders is probably a result of both lower premorbid intelligence and more intellectual decline.
AB - Background: Existing studies on intellectual consequences of alcohol-related disorders are primarily cross-sectional and compare intelligence test scores of individuals with and without alcohol-related disorders, hence mixing the influence of alcohol-related disorders and predisposing factors such as premorbid intelligence. In this large-scale study, the primary aim was to estimate associations of alcohol-related disorders with changes in intelligence test scores from early adulthood to late midlife. Methods: Data were drawn from a follow-up study on middle-aged men, which included a re-examination of the same intelligence test as completed in young adulthood at military conscription (total analytic sample = 2,499). Alcohol-related hospital diagnoses were obtained from national health registries, whereas treatment for alcohol problems was self-reported at follow-up. The analyses included adjustment for year of birth, retest interval, baseline intelligence quotient (IQ) score, education, smoking, alcohol consumption, and psychiatric and somatic comorbidity. Results: Individuals with alcohol-related hospital diagnoses (8%) had a significantly lower baseline IQ score (95.0 vs. 100.5, p ' 0.001) and a larger decline in IQ scores from baseline to follow-up (−8.5 vs. −4.8, p ' 0.001) than individuals without such diagnoses. The larger decline in IQ scores with alcohol-related hospital diagnoses remained statistically significant after adjustment for all the covariates. Similar results were revealed when IQ scores before and after self-reported treatment for alcohol problems (10%) were examined. Conclusions: Individuals with alcohol-related disorders have a lower intelligence test score both in young adulthood and in late midlife, and these disorders, moreover, seem to be associated with more age-related decline in intelligence test scores. Thus, low mean intellectual ability observed in individuals with alcohol-related disorders is probably a result of both lower premorbid intelligence and more intellectual decline.
KW - Alcohol-Related Disorders
KW - Intellectual Changes
KW - Intelligence
KW - Intelligence Quotient
KW - Longitudinal Study
U2 - 10.1111/acer.14174
DO - 10.1111/acer.14174
M3 - Journal article
C2 - 31386205
AN - SCOPUS:85070962353
SN - 0145-6008
VL - 43
SP - 2187
EP - 2195
JO - Alcoholism: Clinical and Experimental Research
JF - Alcoholism: Clinical and Experimental Research
IS - 10
ER -