Cognitive function in aging cocaine smokers

Background: Little is known about the functional status of older drug users, who may pose challenges to public health systems in coming years. Here, we assessed cognitive function in aging cocaine smokers compared to demographically matched controls. Methods: A total of 22 non-treatment-seeking aging (50-60 years old) cocaine smokers (> twice/week; > 15 years of weekly use) and 19 controls completed a comprehensive cognitive battery. Controls with cannabis, tobacco, and alcohol use were included to better match the cocaine users. All cocaine users, and current cannabis- or alcohol-using controls, completed testing after 4 drug-free inpatient days to better control for acute and residual drug effects. Results: Cocaine users (52.9 +/- 2.5 years old, four female; cocaine use 3.9 +/- 1.4 days/week) and controls (52.7 +/- 2.6 years old, four female) were well matched demographically, but cocaine users reported a more extensive substance use profile. Cocaine users showed marginally worse verbal learning than controls, recalling on average one word fewer across immediate and delayed word recall trials. Their performance was intact relative to controls across all other measures of cognitive function. Bayesian analysis indicated the absence of group differences was not due to power limitations. Conclusion: These data suggest that aging, long-term cocaine users have similar cognitive functioning to appropriately matched controls when tested under drug-free conditions, with only marginal decreases in verbal learning. Findings, although reassuring with regard to broad cognitive capacities in aging cocaine smokers, suggest that future investigations of cognitive function in aging drug users are warranted.