Three-week beta-adrenergic blockade does not impair or improve general intellectual function in young healthy males

The widespread use of beta blockers in treatment of both cardiovascular and nonvascular conditions has generated interest in changes in functions of the central nervous system during treatment. We studied the effect of 3 weeks of beta blockade on learning and memory ability, concentration, and verbal abstraction in 32 young normotensive healthy men. We chose healthy males to exclude the possible influence of changes related to a hypertensive state. Subjects were randomized into a 3-week treatment protocol with either atenolol 50 mg X 2 (cardioselective, hydrophilic), metoprolol 100 mg X 2 (cardioselective, lipophilic), propranolol 80 mg X 2 (noncardioselective, lipophilic), or placebo X 2. Each subject underwent two neuropsychological testing sessions. We found no significant enhancement or impairment of intellectual or psychomotor performances after the 3-week treatment with beta-adrenergic-blocking agents compared to a placebo-treated control group. Differences in pharmacokinetic profiles of the drugs (e.g., central nervous system penetrability, lipophilicity, or membrane-stabilizing effect) did not influence the test outcome. Antihypertensive treatment with beta blockers over a prolonged period does not affect young peoples' learning and memory abilities or reasoning powers, nor their ability to concentrate and perform psychometric tasks.