Biomedical subjects

B Pedrosi

Publications and source records attributed to B Pedrosi.

4 recordsLinked to original sources

PubMed2001

Treatment regimen and hypnotic self-administration.

RATIONALE AND OBJECTIVES: Previous studies have shown that insomniacs self-administer hypnotics at high nightly rates. This study determined whether prior experience with different treatment regimens (i.e., instructions and capsule availability) would alter the previously observed high hypnotic self-administration rates. METHODS: Sixty-four healthy men and women with (n = 32) and without (n = 32) insomnia, 21-55 years, self administered placebo or triazolam (0.25 mg) after different prior treatment regimens. They received one of three different treatment regimens enforced for 11 nights: a capsule each night, a capsule as needed, or a capsule every third night. On 14 subsequent nights they choose to self-administer a capsule or not, placebo during 1 week and triazolam (0.25 mg) the other (counterbalanced in order). RESULTS: Insomniacs self-administered more capsules than normals and triazolam was self-administered more than placebo. For both groups, treatment regimen had a minimal effect on capsule self-administration. During the treatment phase, triazolam improved self-ratings of sleep relative to placebo. During the choice phase, nightly variations in self-rated sleep predicted self-administration of a capsule on the following night, regardless of whether the capsule was active drug or placebo. CONCLUSIONS: The data of this study are consistent with the view that hypnotic self-administration by insomniacs is therapy-seeking behavior and not drug abuse.

Adult↗

PubMed1997

Hypnotic self administration: forced-choice versus single-choice.

Twenty-four men and women with insomnia, age 21-50 years, self administered hypnotics under a single-choice with placebo, single-choice with triazolam (0.25 mg), or forced-choice of placebo versus triazolam (0.25 mg) paradigm. Subjects received 4- sampling nights of placebo or triazolam in the single-choice conditions or 2 nights of each in the forced-choice condition. Then on 7 choice nights they could self administer a capsule, or not, in the single-choice conditions, or were required to choose one of two color-coded capsules in the forced-choice condition. In the single-choice conditions, subjects chose placebo 80% of nights and triazolam 77% of nights, while in the forced-choice condition triazolam was chosen on 86% of nights. Thus, the self administration of triazolam did not vary significantly between single or forced choice conditions, but that of placebo did. Placebo rate was high when it was the only alternative, but low when competing with triazolam. On sampling nights, compared to placebo, triazolam produced a significant increase in total sleep time, a reduction in latency to sleep, wake after sleep onset, and percentage stage 1 sleep. Triazolam, relative to placebo, also improved mood in the morning on some sampling nights. For subjects choosing capsules < 100% of opportunities (n = 14), on nights a capsule was chosen versus nights none was chosen (regardless of whether placebo or triazolam was the choice), self-ratings 30 min before bedtime on the Profile of Mood States vigor scale were significantly higher.

Adult↗

PubMed1996

Hypnotic self administration and dose escalation.

The dependence liability of benzodiazepines in the context of their use as hypnotics (i.e. by insomnia patients as pre-sleep medications) is unresolved. A recent study found that insomniacs self administer capsules at bedtime at a high rate, with triazolam (0.25 mg) taken as often as placebo. This study sought to determine if differential self administration would develop when multiple capsules are available nightly. Eighteen men and women, age 21-45 years, with insomnia complaints (nine with objective sleep disturbance and nine without) were studied, 1 week with placebo and 1 week with triazolam (0.25 mg). The two conditions were administered double-blind and presented in a counter-balanced order with a week between conditions. In each condition, after 3 consecutive sampling nights of the available single capsule for that condition, subjects could self administer 0-3 capsules before bed on the 4 subsequent nights. Triazolam was self administered as many nights as placebo, but the number of placebo capsules self administered was twice that of triazolam capsules. The objective insomniacs self administered more capsules than the subjective insomniacs and neither group differentially choose triazolam over placebo. The number of triazolam capsules taken nightly was stable and the number of placebo capsules variable. It is concluded that insomniacs show no short-term escalation of triazolam dose, but do choose an increased and variable number of placebos, a pattern which is interpreted as being insomnia relief-seeking behavior.

Adult↗

PubMed1995

Neuropsychological function in obstructive sleep apnea syndrome (OSAS) compared to chronic obstructive pulmonary disease (COPD).

Forty-nine men, 25 with obstructive sleep apnea syndrome (OSAS) and 24 with chronic obstructive pulmonary disease (COPD), were evaluated with a standard 8-hour nocturnal polysomnogram, multiple sleep latency test the following day and a neuropsychological test battery. The OSAS patients had more respiratory disturbances per hour of sleep, more stage 1 sleep and greater daytime sleepiness than COPD patients. The OSAS patients were as impaired as the COPD patients in neuropsychological test functioning, with the pattern of impairment nonspecific as to hypoxemic-sensitive versus sleepiness-sensitive tasks, with two exceptions. The OSAS patients performed more poorly on a test requiring sustained attention and considered sensitive to sleepiness, whereas the COPD patients performed more poorly on a test requiring motor skills and sensitive to hypoxemia. These deficits in psychomotor and attention appear to be specifically related to patients group (OSAS vs. COPD), but the other deficits found in complex reasoning and memory are nonspecific.

Attention↗