Biomedical subjects
K L Tyson
Publications and source records attributed to K L Tyson.
Next-day memory impairment with triazolam use.
The prevalence, rate, and degree of memory impairment for next-day activities during a short, intermittent course of bedtime doses of triazolam, temazepam, and placebo were assessed in a double-blind parallel-group study. 5 of the 6 subjects in the triazolam group reported at least one episode of next-day memory impairment/amnesia, with a total of 12 episodes being reported for the 30 subject-drug nights (a rate of 40%). In the temazepam group there were no such episodes of memory impairment. Immediate and delayed recall were also tested and related to whether active drug or placebo had been taken the night before. Impairment of delayed recall was significantly and several times greater than that in the temazepam or placebo groups. Next-day memory impairment/amnesia after a bedtime dose of triazolam tended to increase with continued or intermittent drug use. Cognitive impairments associated with triazolam probably represent a spectrum of organic brain dysfunction, with memory impairment/amnesia and confusion being the commonest, and milder manifestations and hallucinations and delusions the more severe and less common, features.
Effects of lovastatin and pravastatin on sleep efficiency and sleep stages.
The effects on sleep of two 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (40 mg lovastatin and 40 mg pravastatin) were evaluated in 12 normal subjects in a double-blind placebo-controlled sleep laboratory study. Subjects were randomly assigned to each of two parallel groups (lovastatin and pravastatin). Each parallel-group protocol consisted of 22 consecutive nights including 4 placebo-baseline nights, 2 weeks of drug administration, and 4 placebo-withdrawal nights. Lovastatin did not disturb sleep initially (nights 5 through 7) but, with continued administration (nights 16 through 18), it significantly and markedly increased wake time after sleep onset and stage 1 sleep compared with baseline. By contrast, pravastatin was not associated with sleep disturbance either initially or with continued use. Neither drug caused any sleep disturbance after withdrawal. Lovastatin's sleep disturbing effects with continued administration are attributed to its high degree of lipophilicity in contrast with the hydrophilicity of pravastatin.