To determine the prevalence of cocaine use and associated risk factors in African Americans volunteering as research subjects for a hypertension study.Methods:
African Americans recruited from Milwaukee's inner city received $25 for completing a blood pressure screening protocol with the potential to participate in an additional protocol for $200, contingent on a negative drug test for cocaine. This study is based on the characteristics of the participants who completed the drug screen for cocaine. The significance of differences in the frequencies of categorical variables between users and nonusers was determined by χ2 analysis or Fisher exact test.Results:
Of 389 drug-tested participants, 35% tested positive for cocaine. Cocaine positive volunteers were slightly older (P = 0.02), had a lower body mass index (P = 0.001), a smaller waist circumference (P = 0.005), and lower serum cholesterol levels (P = 0.04). Those testing positive were more likely to be tobacco smokers (P < 0.0001), unemployed (P = 0.001), and alcohol users (P < 0.0001), but less likely to use prescription medications (P = 0.01). Income and education did not differ between cocaine positive and negative subjects. Individuals employed full-time were less likely to test positive than the unemployed, whereas part-time employees were intermediate (P = 0.0003). Although those testing positive were slightly less likely to have a living mother (P = 0.07), there was no association with living fathers.Results:
Cigarette smokers were almost five times more likely to test positive for cocaine than nonsmokers (OR 4.88, 95% CI 2.73–8.71). Additional predictors of positive tests were alcohol consumption (OR 1.90, 95% CI 1.18–3.19), a reported history of substance abuse (OR 1.83, 95% CI 1.05–3.19), and a family history that included one or more deceased siblings (OR 1.82, 95% CI 1.03–3.21).Conclusions:
A high prevalence of substance use was detected among inner city African Americans offered financial incentives for participating in a general medical research protocol. This information may be relevant for designing future clinical trials and drug use intervention programs.