Effect of marijuana and placebo-marijuana smoking on psychological state and on psychophysiological cardiovascular...

Ten male anginal patients with angiographically documented coronary artery disease, in a randomized double-blind crossover study, smoked one marijuana cigarette (containing 18 mg of delta-9-THC) on one morning and one placebo marijuana cigarette (containing 0.05 mg of delta-9-THC) on a successive morning. Significant increases occurred in average cognitive and intellectual impairment scores, derived from the objective content analysis of 5 min of speech, 30 mins after smoking the marijuana cigarette as compared to the placebo marijuana cigarette, and these scores decreased to near presmoking levels 60 min after smoking. No significant average changes occurred in anxiety or three hostility scale scores following smoking marijuana. Sizable individual differences were noted in the psychological responses to marijuana smoking due, presumably, to personality differences and/or differences in THC pharmacokinetics. Significant psychocardiovascular hemodynamic correlations, as measured by echocardiography, were observed during placebo-marijuana smoking between hostility inward scores and systolic blood pressure and ejection fraction, overt hostility outward scores and diastolic blood pressure, as well as between anxiety scores and stroke volume and left ventricular end-diastolic dimension and left ventricular diastolic volume. These significant psychophysiologic correlations were all eliminated during marijuana smoking. In view of associated findings that marijuana smoking decreased myocardial oxygen delivery, decreased exercise time until the onset of anginal pain, and increased myocardial oxygen demand in anginal patients, the use of marijuana by such patients is clearly inadvisable.