Impact of short-acting vs. standard anaesthetic agents on obstructive sleep apnoea: a randomised, controlled, triple-blind trial.

Sleep apnoea is associated with negative outcomes following general anaesthesia. Current recommendations suggest using short-acting anaesthetic agents in preference to standard agents to reduce this risk, but there is currently no evidence to support this. This randomised controlled triple-blind trial tested the hypothesis that a combination of short-acting agents (desflurane-remifentanil) would reduce the postoperative impact of general anaesthesia on sleep apnoea severity compared with standard agents (sevoflurane-fentanyl). Sixty patients undergoing hip arthroplasty under general anaesthesia were randomised to anaesthesia with desflurane-remifentanil or sevoflurane-fentanyl. Respiratory polygraphy was performed before surgery and on the first and third postoperative nights. The primary outcome was the supine apnoea-hypopnoea index on the first postoperative night. Secondary outcomes were the supine apnoea-hypopnoea index on the third postoperative night, and the oxygen desaturation index on the first and third postoperative nights. Additional outcomes included intravenous morphine equivalent consumption and pain scores on postoperative days 1, 2 and 3. Pre-operative sleep study data were similar between groups. Mean (95%CI) values for the supine apnoea-hypopnoea index on the first postoperative night were 18.9 (12.7-25.0) and 21.4 (14.2-28.7) events.h-1 , respectively, in the short-acting and standard anaesthesia groups (p = 0.64). Corresponding values on the third postoperative night were 28.1 (15.8-40.3) and 38.0 (18.3-57.6) events.h-1 (p = 0.34). Secondary sleep- and pain-related outcomes were generally similar in the two groups. In conclusion, short-acting anaesthetic agents did not reduce the impact of general anaesthesia on sleep apnoea severity compared with standard agents. These data should prompt an update of current recommendations.

A randomised controlled trial of shoulder block vs. interscalene brachial plexus block for ventilatory function after shoulder arthroscopy.

The shoulder block may impair ventilatory function and diaphragmatic movement less than the interscalene brachial plexus block. We randomly allocated 30 adults who underwent shoulder arthroscopy under general anaesthesia to ultrasound-guided shoulder block or interscalene block with 20 ml bupivacaine 0.5%. The primary outcome, rate of ultrasound-measured hemidiaphragmatic excursion < 25% of baseline 30 min after blockade, was reduced from 12/15 with brachial plexus block to 2/15 with shoulder block, a difference (95%CI) of 67% (40-93%), p < 0.001. The mean (SD) numeric rating scale pain scores at rest after shoulder block were higher than after interscalene block at two postoperative hours, 1.4 (1.2) vs. 0.3 (0.7), p = 0.02, but lower at 24 postoperative hours, 1.3 (1.3) vs. 3.4 (2.3), p = 0.008. Mean (SD) pain scores on movement in the shoulder and interscalene blocks were similar, with respective values of 1.9 (1.9) vs. 0.7 (1.2), p = 0.13 at two postoperative hours and 3.7 (2.3) vs. 5.3 (2.5), p = 0.41, at 24 postoperative hours.

The interaction between erectile dysfunction complaints and depression in men: a cross-sectional study about sleep, hormones and quality of life.

Depression (DEP) is one of the main disabling diseases and is considered a contributor factor for erectile dysfunction (ED). Both of these conditions may be associated with hormonal changes and sleep disturbances. We aimed to evaluate the interaction between ED complaints and depression symptoms on sleep parameters, hormone levels and quality of life in men. This was a cross-sectional study of 468 men aged 20-80 years. The participants were classified according to the presence of ED and/or DEP in groups of healthy individuals, ED, DEP and DEP with ED (DEP-ED). All participants completed questionnaires about sleep, clinical history and quality of life, and underwent polysomnography with blood collection the following morning. ED participants showed higher frequency of insomnia symptoms (65.5%), whereas DEP group had more complaints of difficulty in falling asleep and early morning awakening. In the polysomnography, all groups showed similar parameters. No differences were found in cortisol and total testosterone levels; however, free testosterone levels and the physiological domain of quality of life were lower in DEP-ED group. ED and DEP, as independent factors, negatively affected subjective sleep parameters. The interaction between these factors led to a low quality of life and was related to a decrease in free testosterone levels.

Musculoskeletal pain and the reproductive life stage in women: is there a relationship?

Objectives To investigate the association between reproductive life stage, pain perception and musculoskeletal pain complaint in a representative sample of women from São Paulo, Brazil. Methods A population-based survey was carried out with 574 women who were classified as being in the premenopausal or postmenopausal stage. They answered questions about pain perception and musculoskeletal pain. Follicle stimulating hormone was collected to confirm menopausal condition along with clinical evaluation. Results In the whole sample, we found a prevalence of 56% for pain perception and 20.2% for complaints of musculoskeletal pain. Regarding the topography of musculoskeletal pain, the distributions were similar among the premenopausal and postmenopausal groups. No significant association was found between reproductive life stage and pain perception, as 58.1% of the premenopausal group and 52.0% of the postmenopausal group reported pain. Similarly, there was no significant association between menopausal stage and musculoskeletal pain, as 19.5% and 21.6% of the premenopausal and postmenopausal women, respectively, complained of musculoskeletal pain. There was no significant association of postmenopausal stage (early or late) with pain perception or musculoskeletal pain. The use of analgesics was significantly higher in postmenopausal compared to premenopausal women (p < 0.001). Conclusion A high prevalence of pain was found in women from the city of São Paulo. However, neither the presence of musculoskeletal pain nor pain perception were associated with the reproductive life stage, showing that both parameters was independent from the menopausal status in the studied women.

Musicians and Dystonia: Is Sleep Part of the Problem?

We would like to congratulate Lee and Altenmüller for their recent study showing important findings about the characterization of a task-specific dystonia in a young professional percussionist. The authors presented in an elegant way the EMG investigation and treatment approach and the possible differential diagnoses, raising an important question about the need for physicians' awareness of this condition when considering musicians' health. We would like to add a new point of view in order to contribute with this discussion and provide critical thinking for a multidisciplinary approach to this type of dystonia, which may affect many individuals and result in severe compromise of musical technical performance. One factor that could also be potentially associated with the percussion-related dystonia is sleep.

Sleep fragmentation promotes NADPH oxidase 2-mediated adipose tissue inflammation leading to insulin resistance in mice.

BACKGROUND: Short sleep has been implicated in higher risk of obesity in humans, and is associated with insulin resistance. However, the effects of fragmented sleep (SF) rather than curtailed sleep on glucose homeostasis are unknown. METHODS: Wild-type and NADPH oxidase 2 (Nox2) null male mice were subjected to SF or sleep control conditions for 3 days to 3 weeks. Systemic and visceral adipose tissue (VAT) insulin sensitivity tests, glucose tolerance test, fluorescence-activated cell sorting and immunohistochemistry for macrophages and its sub-types (M1 and M2), and Nox expression and activity were examined. RESULTS: Here we show that SF in the absence of sleep curtailment induces time-dependent insulin resistance, in vivo and also in vitro in VAT. Oxidative stress pathways were upregulated by SF in VAT, and were accompanied by M1 macrophage polarization. SF-induced oxidative stress, inflammation and insulin resistance in VAT were completely abrogated in genetically altered mice lacking Nox2 activity. CONCLUSIONS: These studies imply that SF, a frequent occurrence in many disorders and more specifically in sleep apnea, is a potent inducer of insulin resistance via activation of oxidative stress and inflammatory pathways, thereby opening the way for therapeutic strategies.

The association between TNF-α and erectile dysfunction complaints.

Inflammatory markers like tumour necrosis factor-alpha (TNF-α) have been related to erectile dysfunction (ED) and may interact with other cardiovascular risk factors such as obstructive sleep apnoea syndrome (OSAS). The aim of this study was to examine the inflammatory, metabolic and hormonal profile of men with or without ED complaints and/or OSAS recruited through the Epidemiologic Sleep Study (EPISONO). A sample of 363 men completed sexual questionnaires for ED and had physical and blood examinations. OSAS was evaluated by polysomnography and clinical assessment. The blood samples were used for determination of TNF-α, interleukin-6, leptin, cholesterol and fractions, triglycerides, homocysteine, glucose and hormonal levels. After controlling for confounding factors, men with ED complaints presented higher systolic blood pressure and TNF-α, independent of OSAS. Significant interaction between ED and OSAS was only observed for neck circumference, which was higher in ED men with OSAS than men with OSAS without ED and men with ED without OSAS. Binary logistic regression showed that the predictor factors for ED were age >43 years, myocardial infarction events, TNF-α and systolic blood pressure. Finally, a receiver-operating characteristics curve suggested a cut-off point of 9.95 pg/mL for TNF-α with sensitivity of 60% and specificity of 59% in men with ED complaints. Furthermore, there was a significant association between high levels of TNF-α (>9.95 pg/mL) and the presence of ED complaints. The results showed that there was an association between TNF-α levels and ED complaints in men independent of OSAS.

Sleep loss and acute drug abuse can induce DNA damage in multiple organs of mice.

The purpose of the present study was to characterize the genetic damage induced by paradoxical sleep deprivation (PSD) in combination with cocaine or ecstasy (3,4-methylenedioxymethamphetamine; MDMA) in multiple organs of male mice using the single cell gel (comet) assay. C57BL/6J mice were submitted to PSD by the platform technique for 72 hours, followed by drug administration and evaluation of DNA damage in peripheral blood, liver and brain tissues. Cocaine was able to induce genetic damage in the blood, brain and liver cells of sleep-deprived mice at the majority of the doses evaluated. Ecstasy also induced increased DNA migration in peripheral blood cells for all concentrations tested. Analysis of damaged cells by the tail moment data suggests that ecstasy is a genotoxic chemical at the highest concentrations tested, inducing damage in liver or brain cells after sleep deprivation in mice. Taken together, our results suggest that cocaine and ecstasy/MDMA act as potent genotoxins in multiple organs of mice when associated with sleep loss.

An exact test for the association between the disease and alleles at highly polymorphic loci with particular interest in the haplotype analysis.

The association analysis between the disease and genetic alleles is one of the simple methods for localizing the susceptibility locus in the genes. For revealing the association, several statistical tests have been proposed without discussing explicitly the alternative hypotheses. We therefore specify two types of alternative hypotheses (i.e., there is only one susceptibility allele in the locus, and there is an extension or shortening of alleles associated with the disease) and derive exact tests for the respective hypotheses. We also propose to combine these two tests when the prior knowledge is not sufficient enough to specify one of these two hypotheses. In particular, these ideas are extended to the haplotype analysis of three-way association between the disease and bivariate allele frequencies at two closely linked loci. As a by-product, a factorization of the probability distribution of the three-way cell frequencies under the null hypothesis of no three-way interaction is obtained.

A contribution to genome-wide association studies: search for susceptibility loci for schizophrenia using DNA microsatellite markers on chromosomes 19, 20, 21 and 22.

As an initial step for genome-wide association studies, we sought an association between schizophrenia and 34 microsatellite markers on chromosomes 19, 20, 21 and 22 by a case-control design. The samples examined for an association were 168 schizophrenic patients and 146 control subjects in the Japanese population. The allele distribution of the 34 loci differed significantly between Japanese and French populations. Significant deviation from the Hardy-Weinberg equilibrium was observed at D19S209 and D21S1256 in the control subjects. Case-control comparisons of the initial screening revealed a significant difference in allele frequency at D20S95 and a trend of difference at D20S118. To confirm these possible associations, additional samples consisting of 110 schizophrenic patients and 116 control subjects were examined, and an association between D20S95 and schizophrenia was confirmed (corrected P value after Bonferroni correction, 0.00035). D20S95 is located close to the gene (CHGB) encoding chromogranin B. These findings suggest that CHGB could be an important candidate gene involved in the development of schizophrenia.