As we age, we all lose grey matter. However, what we have seen is that chronic cocaine users lose grey matter at a significantly faster rate, which could be a sign of premature ageing. Our findings therefore provide new insight into why the cognitive deficits typically seen in old age have frequently been observed in middle aged chronic users of cocaine."—Dr Karen Ersche, of the Behavioural and Clinical Neuroscience Institute (BCNI) at the University of Cambridge
New research by scientists at the University of Cambridge suggests that chronic cocaine abuse accelerates the process of brain ageing. The study, published today in Molecular Psychiatry, found that age-related loss of grey matter in the brain is greater in people who are dependent on cocaine than in the healthy population.
For the study, the researchers scanned the brains of 120 people with similar age, gender and verbal IQ. Half of the individuals had a dependence on cocaine while the other 60 had no history of substance abuse disorders.
The researchers found that the rate of age-related grey matter volume loss in cocaine-dependent individuals was significantly greater than in healthy volunteers. The cocaine users lost about 3.08 ml brain volume per year, which is almost twice the rate of healthy volunteers (who only lost about 1.69 ml per year). The accelerated age-related decline in brain volume was most prominent in the prefrontal and temporal cortex, important regions of the brain which are associated with attention, decision-making, and self-regulation as well as memory.
Previous studies have shown that psychological and physiological changes typically associated with old age such as cognitive decline, brain atrophy and immunodeficiency are also seen in middle-aged cocaine-dependent individuals. However, this is the first time that premature ageing of the brain has been associated with chronic cocaine abuse.