Carotid intima media thickness in patients with obstructive sleep apnea: comparison with a community-based cohort.

Background: The impact of obstructive sleep apnea (OSA) on the development of atherosclerotic cardiovascular disease (CVD) in the absence of overt CVD or risk factors is unclear. Our purpose was to assess whether patients with OSA without overt CVD or risk factors have subclinical atherosclerosis as evaluated by carotid intima medial thickness (CIMT) compared to matched controls.

Methods: We measured CIMT in patients >40 years old, who underwent polysomnography for suspected OSA and did not have a history of CVD or risk factors (smoking, hypertension, diabetes, hyperlipidemia).

Effects of 10 days of modest intermittent hypoxia on circulating measures of inflammation in healthy humans.

Purpose: Obstructive sleep apnea (OSA) is a common disease which is associated with elevated inflammatory markers and adhesion molecules, possibly due to nightly intermittent hypoxia (IH). The purpose of this study was to test the hypothesis that IH would increase systemic inflammatory markers in healthy human males.

Methods: Healthy, young male subjects (n = 9; 24 ± 2 years) were exposed to a single daily isocapnic hypoxia exposure (oxyhemoglobin saturation = 80%, 1 h/day) for 10 consecutive days.

Residual sleep apnea on polysomnography after 3 months of CPAP therapy: clinical implications, predictors and patterns.

Objective: We sought to determine the clinical implications, predictors and patterns of residual sleep apnea on continuous positive airway pressure (CPAP) treatment in patients with moderate-to-severe obstructive sleep apnea (OSA).

Methods: We performed a post hoc secondary analysis of data from a previously reported randomized trial. Sleepy patients with a high risk of moderate-to-severe OSA identified by a diagnostic algorithm were randomly assigned to standard CPAP titration during polysomnography (PSG) or ambulatory titration using auto-CPAP and home sleep testing.

Pro-atherogenic cytokine profile of patients with suspected obstructive sleep apnea.

Purpose: Systemic inflammation is important in the pathogenesis of cardiovascular disease (CVD). We sought to characterize the systemic inflammatory profile associated with obstructive sleep apnea (OSA).

Methods: Adult patients referred for suspected OSA at the University of British Columbia Hospital Sleep Disorders Program were recruited for our study.

Depression and sleep-related symptoms in an adult, indigenous, North American population.

Study Objectives: Symptoms related to sleep disorders are common and may have substantial adverse impacts on mental health. Indigenous North Americans (American Indian) are a medically vulnerable population with reduced access to healthcare services. The purposes of this study were to assess (1) the prevalence of sleep symptoms and (2) the relationships between symptoms and depression in this population.

Alpha-1-antitrypsin deficiency: current concepts.

Since the condition was first described four decades ago, alpha-1-antitrypsin (A1AT) deficiency has served as a model for other disease processes. A1AT is the archetypal serpin designed to ensnare proteases, a process that involves significant conformational change within the molecule. Mutations in the A1AT gene lead to misfolding of the protein and accumulation within the endoplasmic reticulum of hepatocytes resulting in two different pathologic processes.

Prevalence, risk factors and impact on daytime sleepiness and hypertension of periodic leg movements with arousals in patients with obstructive sleep apnea.

Study Objective: To determine the prevalence, risk factors, and impact on daytime sleepiness and hypertension of periodic leg movements of sleep (PLMS) with associated arousals in patients with obstructive sleep apnea (OSA).

Methods: A single-center retrospective case series of 798 consecutive patients who underwent diagnostic overnight polysomnography for suspected OSA. We performed discriminant function analysis using clinical and polysomnographic variables to examine the relationship between PLMS (periodic leg movement arousal index > or =5 per hour) and potential risk factors, including OSA.

Diagnosis and initial management of obstructive sleep apnea without polysomnography: a randomized validation study.

Background: Polysomnography (PSG), despite limited availability and high cost, is currently recommended for diagnosis of obstructive sleep apnea and titration of effective continuous positive airway pressure (CPAP).

Objective: To test the utility of a diagnostic algorithm in conjunction with ambulatory CPAP titration in initial management of obstructive sleep apnea.

Design: A randomized, controlled, open-label trial that compared standard PSG with ambulatory CPAP titration in high-risk patients identified by a diagnostic algorithm.

Z alpha1-antitrypsin polymerizes in the lung and acts as a neutrophil chemoattractant.

Background: Alpha1-antitrypsin (A1AT) is an abundant protein that is synthesized in the liver and is secreted into the plasma. From the plasma, A1AT diffuses into various body compartments, including the lung where it provides much of the antiprotease protection. The current understanding of the pathogenesis of emphysema in A1AT-deficient individuals focuses on the polymerization of mutant protein within the liver, which results in a deficiency of circulating A1AT and a protease-antiprotease imbalance in the lungs.

Activation of endoplasmic reticulum-specific stress responses associated with the conformational disease Z alpha 1-antitrypsin deficiency.

Conformational diseases are a class of disorders associated with aberrant protein accumulation in tissues and cellular compartments. Z alpha1-antitrypsin (A1AT) deficiency is a genetic disease associated with accumulation of misfolded A1AT in the endoplasmic reticulum (ER) of hepatocytes. We sought to identify intracellular events involved in the molecular pathogenesis of Z A1AT-induced liver disease using an in vitro model system of Z A1AT ER accumulation.