Developmental differences in childhood motor coordination predict adult alcohol dependence: proposed role for the cerebellum in alcoholism

BACKGROUND: The Danish Longitudinal Study of Alcoholism has identified a number of early biological indicators that predicted alcohol dependence 30 years later. In light of recent evidence linking deficits of the cerebellum to certain neuropsychiatric disorders often comorbid with alcoholism, we hypothesized that developmental deficits in the cerebellar vermis may also play a role in the initiation of adult alcohol dependence. The present study evaluated whether measures of motor development in the first year of life predict alcohol dependence three decades later.

METHODS: A total of 241 subjects of the original 330 infants who were entered into this study completed the 30-year follow-up (12 had died). The subjects were men who were drawn from a large birth cohort born in Copenhagen, Denmark, from 1959 to 1961. A comprehensive series of measures were obtained on each subject before, during, and shortly after birth as well as at 1 year of age. Muscle tone at birth and day 5 as well as 1-year measures of motor coordination--age to sitting, standing, and walking--were examined. A DSM-III-R diagnosis of alcohol dependence and a measure of lifetime problem drinking served as the 30-year outcome variables.

RESULTS: Several measures of childhood motor development significantly predicted alcohol dependence at 30 years of age. These included deficits in muscle tone 5 days after birth, delays in the age to sitting, and delays in the age to walking.

CONCLUSIONS: Relationships found between adult alcoholism and early delays in motor development offer support for the theory that cerebellar deficits may play a causal role in the addiction process.