Biomedical subjects

Natalie Tarquinio

Publications and source records attributed to Natalie Tarquinio.

5 recordsLinked to original sources

PubMed2005

Cerebral structural changes in severe obstructive sleep apnea.

Obstructive sleep apnea is associated with abnormalities in neuropsychologic function, and defects in respiratory control may contribute to pathogenesis. Abnormalities may be reflected in structural brain changes. Twenty-seven male untreated patients with severe sleep apnea without comorbidities, and 24 age-matched control subjects, had T1-weighted brain imaging in a high-resolution magnetic resonance scanner. Twenty-three patients with sleep apnea had repeat imaging after 6 months of continuous positive airways pressure treatment. No areas of gray matter volume change were found in patients using an optimized voxel-based morphometry technique, at p < 0.05 adjusted for multiple comparisons (despite the method being sensitive to changes in gray matter fraction of 0.17 or less in all voxels). Furthermore, no differences were seen in bilateral hippocampal, temporal lobe, or whole brain volumes, assessed by manual tracing of anatomical borders. No longitudinal changes were seen in gray matter density or regional volumes after treatment, but whole brain volume decreased slightly. We have found no gray matter volume deficits nor focal structural changes in severe obstructive sleep apnea. Whole brain volume decreases without focal changes after 6 months of continuous positive airways pressure treatment.

Adult↗

PubMed2005

Sleep disordered breathing in chronic stroke survivors. A study of the long term follow-up of the SCOPES cohort using home based polysomnography.

Prevalence of sleep-disordered breathing (SDB) (apnea-hypopnea index [AHI] > or = 5) in acute stroke patients ranges between 44% and 95%, compared to the community prevalence, 9 to 35% for women and 8 to 57% for men [age range 30-60 years]. Limited data exists beyond 3 months following stroke. We assessed the prevalence of SDB amongst stroke survivors at 3 years and compared results to data reported in normal and elderly populations. 90/143 eligible stroke survivors from an existing cohort underwent a home based sleep study. Mean age of the 78 subjects with a valid sleep study was 64 years (SD 15). Prevalence of SDB (AHI > or = 5) was 81% (95% CI 72% to 90%) and sleep apnoea syndrome (AHI > or = 5 plus ESS score > or =11) was 20% (95% CI 11% to 29%). Important predictors for AHI > or = 15 were haemorrhagic stroke (aOR12.06 [1.42-102.74]) and stroke severity at 1 month (aOR4.15 [1.05-16.38]). Large case-control studies are needed.

Adult↗

PubMed2004

Efficacy of positive airway pressure and oral appliance in mild to moderate obstructive sleep apnea.

The efficacy of currently recommended treatments is uncertain in patients with mild to moderate obstructive sleep apnea (apnea-hypopnea index [AHI], 5-30). A group of 114 sleep clinic patients with an AHI of 5-30 have participated in a randomized controlled crossover trial of 3 months of treatment with each of nasal continuous positive airway pressure (CPAP), a mandibular advancement splint, and a placebo tablet. Outcomes were sleep fragmentation and hypoxemia, daytime sleepiness, quality of life, neurobehavioral function, and blood pressure. Both active treatments improved sleep outcomes, but positive airway pressure had a greater effect. The quality of life, symptoms, and subjective but not objective sleepiness improved to a similar degree with both treatments; however, many of the improvements seen in neuropsychologic function and mood were not better than the placebo effect. Some aspects of nocturnal blood pressure were improved with the splint but not with CPAP. This study has shown that although both CPAP and mandibular advancement splint effectively treated sleep-disordered breathing and sleepiness, the expected response in neurobehavioral function was incomplete. This may be due to the splint having a lesser therapeutic effect and CPAP being poorly tolerated and therefore used less in this patient group.

Continuous Positive Airway Pressure↗

PubMed2004

The maintenance of wakefulness test in normal healthy subjects.

STUDY OBJECTIVES: The Maintenance of Wakefulness Test (MWT) examines an individual's ability to stay awake in an environment of decreased sensory stimulation. Only 1 previous study has systematically examined the MWT in normal healthy subjects. SETTING: Sleep disorders unit laboratory PARTICIPANTS AND DESIGN: 31 subjects (mean age 48.5 years, SD 9.6; 8 women) were randomly selected via the telephone directory within a 30-km radius of the test centers. They answered a general screen for health complaints (respiratory, cardiovascular, and psychiatric disorders) and sleep difficulties (snoring). INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Overnight polysomnography and a 40-minute MWT the following day were performed on all subjects. Mean sleep latency to the first epoch of unequivocal sleep during the 40-minute trial MWT was 36.9 +/- 5.4 (SD) minutes. The lower normal limit, defined as 2 SD below the mean, was therefore 26.1 minutes. Mean sleep latency for the first 20 minutes of the trial (with sleep latency defined as time to the first appearance of 1 epoch of stage 1 sleep or a 10-second microsleep) was 18.6 +/- 2.3 minutes, with a lower normal limit of 14.0 minutes. CONCLUSIONS: The mean results are consistent with previously published normative data. However, the SDs found in this study are smaller, and, thus, the lower normal limit suggested here is 4 to 6 minutes longer. The subjects in this study were randomly selected from the general population and may, therefore, be a truer representation of the normal population than in the previous study in which subjects were recruited via hospital advertisements and word of mouth.

Body Mass Index↗

PubMed2004

Factors associated with maintenance of wakefulness test mean sleep latency in patients with mild to moderate obstructive sleep apnoea and normal subjects.

This study investigated the possible factors related to the Maintenance of Wakefulness Test (MWT) mean sleep latency. A second analysis explored the characteristics of subjects who had discrepant Epworth Sleepiness Scale (ESS) and MWT scores. A total of 151 subjects (110 mild to moderate obstructive sleep apnoea (OSA) patients and 41 control subjects) were recruited for the study. The subjects completed an overnight Polysomnography (PSG), MWT, cognitive, performance and vigilance tasks and answered self-report questionnaires on mood and sleepiness. A forward stepwise multiple regression was performed on MWT mean sleep latency. The predictor variables age (r = 0.28), subjective sleep history for 1 week prior to MWT (sleep diary; r = 0.19) and number of >4% SaO2 Dips during the PSG (r = -0.21) best explained the MWT results, but only accounted for 12.8% of the variance in the test. It was found that 33% of subjects had discrepant ESS and MWT scores. A new variable was created to analyse these subjects (MWT/ESS discrepancy score; MED). A forward stepwise multiple regression analysis found that depression, performance errors and sleep disordered breathing explained 13.4% of the variance in MED scores. The MWT is a complex behavioural test whose scores do not seem to have a very robust relationship with potential predictors and co-correlates. Further comprehensive study is needed if the test is to be used in a diagnostically meaningful way.

Body Mass Index↗