Does menopause influence nocturnal awakening with headache?

OBJECTIVE: The aim of the present study was to assess whether menopausal status influences the occurrence of nocturnal awakening with headache (NAH) in the female population of Sao Paulo, Brazil. We also examined the relationship of this complaint to sociodemographic determinants, hot flushes, sleep quality and parameters, anxiety and depressive symptoms, somnolence and fatigue according to menopausal status. METHODS: The female population of the Sao Paulo Epidemiologic Sleep Study (EPISONO) (n = 576) was divided according to menopausal status (pre-, peri-, early and late menopause) based on questionnaires and hormonal blood measures. The complaint of waking up because of a headache at least once a week was assessed by the UNIFESP Sleep questionnaire. Additionally, hot flushes, sleep complaints, anxiety and depressive symptoms, somnolence and fatigue were assessed by specific questionnaires. A full-night polysomnography assessed sleep parameters. RESULTS: The prevalence of NAH in women in the Sao Paulo population was 13.3%. Perimenopause was associated with a higher risk of having NAH (odds ratio 13.9; 95% confidence interval 4.3-45.2). More complaints of NAH were observed in obese women. All the groups with NAH showed more hot flushes, worse subjective sleep quality, more complaints of insomnia, anxiety symptoms and fatigue. CONCLUSIONS: We observed a constellation of symptoms in women according to menopausal status and NAH that included hot flushes, sleep complaints, more anxiety symptoms and fatigue. Moreover, some of these symptoms were more frequent in perimenopausal women with NAH. Therefore, we concluded that menopausal status influences NAH and the women in perimenopause presented a high risk of having this complaint.

Zolpidem and memory: a study using the process-dissociation procedure.

RATIONALE: There is a dearth of studies which have employed sophisticated paradigms to investigate the effects of zolpidem on memory. OBJECTIVES: To explore anterograde cognitive deficits induced by acute oral doses of zolpidem by means of the process-dissociation procedure (PDP). METHODS: The present study followed a placebo-controlled, double-blind, parallel-group design. Young, healthy females were randomly allocated to one of three treatments with 12 subjects each: placebo, 5 mg and 10 mg zolpidem. Two word-stem completion tasks were carried out close to theoretical peak-plasma concentration: a) direct inclusion task with cued recall, in which participants had to try to use words seen at study to complete stems; and b) direct exclusion task, in which words seen at study were to be avoided as completions. The PDP was applied to the results in these tasks to yield indices of explicit/controlled (C) and implicit/automatic (A) memory. Classical psychometric tests were also carried out. RESULTS: Zolpidem 10 mg led to cognitive effects similar to benzodiazepines (except for the atypical lorazepam), including impairment of exclusion, but not inclusion-task performance. Results of the application of the PDP were inconclusive but concurred with the pattern established in previously published work on benzodiazepine effects, i.e. that zolpidem (10 mg) impaired C. CONCLUSIONS: Zolpidem leads to cognitive effects similar to most benzodiazepines. Although the application of PDP in drug studies may be counterproductive in view of methodological difficulties that are discussed, the pattern of effects on the stem-completion tasks involved in this paradigm is potentially useful in the investigation of cognitive effects of psychoactive drugs.

A double-dissociation of behavioural and event-related potential effects of two benzodiazepines with similar potencies.

This study was designed to explore the role of benzodiazepine affinity to benzodiazepine binding site on acute psychomotor, subjective and memory effects, as well as auditory Event Related Potential (ERP) latencies, in healthy volunteers. Two benzodiazepines with similar affinity to benzodiazepine binding sites, or potency, were compared: the atypical compound lorazepam (2.0 mg), which has been reported to impair priming, and a standard benzodiazepine, flunitrazepam (0.6 mg, 0.8 mg, 1.0 mg). The study followed a placebo-controlled, double-blind, parallel-group design. Sixty subjects completed a test battery before treatment and at theoretical peak plasma concentration of drugs. Lorazepam and 1.0 mg of flunitrazepam led to comparable alterations on psychomotor, subjective and auditory episodic memory measures. A double-dissociation was found for lorazepam and the equipotent dose of flunitrazepam (1.0 mg): lorazepam was more deleterious than flunitrazepam in time taken to identify fragmented shapes. Lorazepam also impaired direct and indirect stem-completion in comparison to placebo, but this effect was abolished when time to identify shapes was used as a covariate. By contrast, 1.0 mg of flunitrazepam prolonged auditory ERP latencies to a greater extent than lorazepam. High affinity to the benzodiazepine binding sites does not seem to explain the consistent lorazepam-induced impairment of indirect stem-completion. Differences in impairment profile between the benzodiazepines employed may relate to the modality (visual or not) of the tasks used.

Sistema para análise simultânea de quatro potenciais evocados visuais multicanais utilizando equipamento comercial e processamento off-line / A system for the simultaneous analysis of four multichannel visual evoked potentials using a commercial equipment and off line processing

Numa proposta de pesquisa para estudar os correlatos eletrofisiológicos de processamento semântico de palavras apresentadas visualmente pretendia-se captar (e processar) quatro potenciais evocados cerebrais de algumas derivações num mesmo experimento, utilizando um equipamento comercial usado em centros hospitalares. Para viabilizar tal pesquisa, foi criado um protocolo especial, em que duas respostas visuais evocadas seqüencialmente, com uma latência de 4,15 s, eram adquiridas em uma mesma janela de aquisição. Como a taxa de amostragem resultante no equipamento foi adequada para a aplicação (100 Hz), foi possível realizar o experimento no próprio centro hospitalar, utilizando um equipamento com o qual os pesquisadores da área biomédica estavam bem familiarizados. Um problema adicional surgiu no tocante a artefatos por movimentação ocular. Este foi sanado graças à possibilidade de serem arquivadas todas as respostas individuais, e não somente a média coerente. Um algoritmo simples realizou a detecção de artefatos de forma eficiente. As soluções encontradas possibilitaram a realização da pesquisa proposta, sendo que essas mesmas soluções poderão permitir trabalhos em outros centos que se deparem com uma problemática semelhante à descrita.