Association between reported sleep need and sleepiness at the wheel: comparative study on French highways between 1996 and 2011.

OBJECTIVE: To investigate the evolution over 15 years of sleep schedules, sleepiness at the wheel and driving risk among highway drivers. METHODS: Comparative survey including questions on usual sleep schedules and before the trip, sleepiness at the wheel, the Epworth sleepiness scale, Basic Nordic Sleep Questionnaire (BNSQ) and a travel questionnaire. RESULTS: 80% of drivers stopped by the highway patrol agreed to participate in both studies with a total of 3545 drivers in 2011 and 2196 drivers in 1996 interviewed. After standardisation based on sex, age and mean annual driving distance, drivers in 2011 reported shorter sleep time on week days (p<0.0001), and week-ends (p<0.0001) and shorter optimal sleep time (p<0.0001) compared to 1996 drivers. There were more drivers sleepy at the wheel in 2011 than in 1996 (p<0.0001) and 2.5 times more drivers in 2011 than in 1996 had an Epworth sleepiness score >15 indicating severe sleepiness. CONCLUSIONS: Even if drivers in 2011 reported good sleep hygiene prior to a highway journey, drivers have reduced their mean weekly sleep duration over 15 years and have a higher risk of sleepiness at the wheel. Sleep hygiene for automobile drivers remains an important concept to address.

Combined caffeine and bright light reduces dangerous driving in sleep-deprived healthy volunteers: a pilot cross-over randomised controlled trial.

AIM OF THE STUDY: To explore the effects of caffeine and bright light therapy on simulated nighttime driving in sleep-deprived healthy volunteers. PARTICIPANTS AND METHODS: Twelve male healthy volunteers aged 20 to 50 years participated in a randomized cross-over study of simulated nighttime driving at a sleep laboratory, followed by recovery sleep with polysomnography at home. The volunteers received variable combinations of caffeine 200mg (C+), caffeine placebo (C-), bright light 10,000 lux (L+), and bright light placebo<50 lux (L-), in four sessions (C+L+, C+L-, C-L+, C-L-), in random order with a wash-out period of 7 days. Treatments were given at 1 a.m. and testing was performed at 1:30 a.m., 3 a.m., 4 a.m., and 6 a.m. Lane drifting was the primary outcome measure. Other measures were reaction times, self-rated fatigue, sleepiness and recovery sleep. RESULTS: Without treatment, lane drifting increased throughout the night, and objective and subjective vigilance declined. Paired comparisons showed that lane drifting was significantly worse at 6 a.m. and at 4 a.m. than at 1:30 a.m. There was a global treatment effect on lane drifting. Lane drifting at 6 a.m. was significantly decreased with C+L+ compared to C-L-. CONCLUSIONS: Bright light therapy combined with caffeine administered at 1 a.m. decreased lane drifting by healthy volunteers during simulated nighttime driving.

Circadian rhythms, melatonin and depression.

The master biological clock situated in the suprachiasmatic nuclei of the anterior hypothalamus plays a vital role in orchestrating the circadian rhythms of multiple biological processes. Increasing evidence points to a role of the biological clock in the development of depression. In seasonal depression and in bipolar disorders it seems likely that the circadian system plays a vital role in the genesis of the disorder. For major unipolar depressive disorder (MDD) available data suggest a primary involvement of the circadian system but further and larger studies are necessary to conclude. Melatonin and melatonin agonists have chronobiotic effects, which mean that they can readjust the circadian system. Seasonal affective disorders and mood disturbances caused by circadian malfunction are theoretically treatable by manipulating the circadian system using chronobiotic drugs, chronotherapy or bright light therapy. In MDD, melatonin alone has no antidepressant action but novel melatoninergic compounds demonstrate antidepressant properties. Of these, the most advanced is the novel melatonin agonist agomelatine, which combines joint MT1 and MT2 agonism with 5-HT(2C) receptor antagonism. Adding a chronobiotic effect to the inhibition of 5-HT(2C) receptors may explain the rapid impact of agomelatine on depression, since studies showed that agomelatine had an early impact on sleep quality and alertness at awakening. Further studies are necessary in order to better characterize the effect of agomelatine and other novel melatoninergic drugs on the circadian system of MDD patients. In summary, antidepressants with intrinsic chronobiotic properties offer a novel approach to treatment of depression.

Self-catheterization acquisition after hand reanimation protocols in C5-C7 tetraplegic patients.

STUDY DESIGN: Case series from a prospectively acquired database and phone survey. OBJECTIVES: To assess the efficacy of upper limb reanimation (ULR) protocols on acquisition of intermittent self-catheterization (ISC) in C5-C7 ASIA tetraplegic patients. SETTING: University Hospital, Paris, France. METHODS: A prospectively acquired database of 152 tetraplegic patients followed in ULR consultation between 1997 and 2008 in a rehabilitation unit was studied. A total of 20 patients met the inclusion criteria, which mainly were traumatic C5-C7 tetraplegic adult patients who were unable to perform ISC, and who benefited from ULR with the objectives of improving hand abilities and of ISC acquisition, through urethral orifice for males or via a continent urinary stoma for females. The main outcome measure was ISC acquisition (ISC+) proportion. Population characteristics and secondary outcome measures: ISC+/ISC- patients were compared regarding epidemiological and surgical data, key-grip strength, patient global improvement score, activities of daily living and quality of life (PGI-I, Wuolle questionnaire, verbal rating scale). RESULTS: ISC+ was 75%. It depended on key-grip strength (P<0.05) and led to a statistically significant improvement of urinary status compared with ISC- patients (P<0.01). ULR improved patients' abilities and QoL in both ISC+ and ISC- patients. CONCLUSION: ULR protocols allow ISC in most C5-C7 tetraplegic patients. Multidisciplinary care with surgeons and PRM physicians improves patients' vital and functional prognosis by changing their urological-management method.

Relation between corset use and lung function postural variation in spinal cord injury.

Corsets are widely used to improve trunk stability in patients with spinal cord injury (SCI) and can improve respiratory function. The aim of the present study was to identify predictors of respiratory benefits from wearing a corset in SCI patients. In a prospective observational study, respiratory function was tested in the supine and upright seated position with and without a corset in 36 SCI patients who regularly used a corset. SCI patients who no longer used a corset were matched to users on sex, injury level and severity. Vital capacity (VC) did not differ between users and nonusers in the supine position. In users, contrary to nonusers, VC increased significantly in the supine position compared to the seated position (increase of 0.43+/-0.39 versus -0.05+/-0.32 L in nonusers; p<0.0001). Corset use was associated with a significant VC increase in the upright position (2.13+/-0.71 L without versus 2.41+/-0.69 L with the corset; p<0.001). The VC increase with the corset in the upright position correlated significantly with the VC increase induced by being supine, compared to sitting without the corset. The VC increase induced in SCI patients by lying supine may predict the effects of wearing a corset. The long-term effects of corset use should be evaluated.

CT of the middiaphyseal femur: cortical bone mineral density and relation to porosity.

PURPOSE: To determine whether computed tomography (CT) can be used to quantify age- and site-related changes in cortical bone mineral density (cBMD) at the middiaphyseal femur and whether cBMD differences are related to intracortical porosity. MATERIALS AND METHODS: Cortical bone specimens from 163 femurs were studied with CT and microradiography. Femurs were from 77 males and 86 females in a white anthropologic collection covering a broad age spectrum. In each sample, the cBMD was measured in the entire cortical width and in periosteal, midcortical, and endosteal subregions of interest. Age- and site-related changes in cBMD were tested for significance by using a two-way analysis of variance for both sexes. By using linear regression, cBMD was compared with porosity in the entire cortical width and in each subregion. RESULTS: There were significant age-related differences in cBMD (P <.001 in females, P =.008 in males). In addition, cBMD values were significantly different between the three cortical subregions (P <.001 for both sexes), decreasing from the periosteum to the midcortex to the endosteum. The cBMD values were closely related to porosity, and porosity contributed to 71.6% of the variance in cBMD in the overall population. CONCLUSION: CT is effective in the measurement of age- and site-related changes in cBMD. Decreases in cBMD are closely correlated with increased cortical porosity.

Quantification of long-chain aldehydes by gas chromatography coupled to mass spectrometry as a tool for simultaneous measurement of plasmalogens and their aldehydic breakdown products.

The cleavage of the specific vinyl ether linkage at the sn-1 position of plasmalogens leads to the formation of two products: the 1-lyso-2-acyl glycerophospholipid and a long-chain fatty aldehyde. Plasmalogens are measured by quantifying one of these two products. In this paper, we describe a rapid and sensitive procedure for measuring plasmalogens via quantification of long-chain fatty aldehydes. After lipid extraction, the sn-1 vinyl ether bond of plasmalogens is cleaved by acidic hydrolysis. The produced aldehydes are then derivatized with (pentafluorobenzyl)hydroxylamine hydrochloride and analyzed by gas chromatography/mass spectrometry in selected-ion mode. Plasmalogens are then indirectly quantified by subtracting the free aldehydes obtained without prior HCl treatment from the total aldehydes obtained after acidic hydrolysis. This method is applied to three rat brain areas selected for this study. Two of these are affected in neurodegenerative diseases (cerebral cortex and hippocampus) and one is rich in white matter (cerebellum). In comparison to other procedures, the advantages of this method are not only its usefulness in plasmalogen quantification but also the identification of aldehydic breakdown products.