Cigarette Smoking and P300 Amplitude in Adults: A Systematic Review

Objective: To determine the association between chronic tobacco cigarette smoking and P300 amplitude. Design: Systematic review with meta-analysis and meta-regression. Data Sources: Medline, Cochrane Database of Systematic Reviews, PsychInfo, and Web of Science. Eligibility Criteria for Selecting Studies: Eligible studies contained P300 amplitudes obtained from either visual or auditory stimuli and standard deviations or errors in female and male subjects older than 18 years in a group of nonabstaining chronic cigarette smokers and a nonsmoking control group. Results: The 9 eligible studies comprised 13 relevant datasets containing 1,956 current cigarette smokers and 2,194 nonsmoking controls (N = 4,150). The P300 amplitude was smaller in cigarette smokers than in nonsmoking controls (Hedges' g effect size = .365; 95% confidence interval [CI] = 0.196-0.534, p < .001). Meta-regression showed significant positive associations between the number of cigarettes smoked per day at the time of the study (slope estimate = .036, 95% CI = 0.016-0.056, p = .001, length of smoking in years (slope estimate = .056, 95% CI = 0.005-0.102, p = .018), pack years (slope estimate = .018, 95% CI = 0.009-0.031 p = .009), and age (slope estimate = .068, 95% CI = 0.025-0.113, p = .002). Conclusions: P300 amplitude was smaller in cigarette smokers than in nonsmoking controls, and a possible dose-response relationship was apparent. Findings indicate a possible association between cigarette smoking and decreased P300 amplitude.