Objectives: Purpose of the study was to assess work productivity in otherwise healthy obstructive sleep apnea (OSA) patients and to explore correlations between work productivity and different characteristics of OSA patients.

Methods: Work productivity was assessed by the Endicott Work Productivity Scale (EWPS) to 115 polysomnographically confirmed OSA patients of working age, without comorbidities. Daytime sleepiness was measured by the Epworth Sleepiness Scale.

Results: A significant correlation was revealed between EWPS and Epworth Sleepiness Scale scores (r2 = 0.127, P < 0.001). Mean EWPS score was significantly higher in somnolent versus nonsomnolent OSA patients (31.2 +/- 16.2 vs 20.8 +/- 11, respectively; P < 0.001). No other sleep or anthropometric characteristic correlated with EWPS.

Conclusions: This study demonstrates the negative effect of daytime sleepiness on work productivity of otherwise healthy OSA patients, highlighting the need of screening for OSA and sleepiness among working individuals.

Source

Júlia Kubitschek Hospital, Fundação Hospitalar do Estado de Minas Gerais-FHEMIG, Hospital Foundation of the state of Minas Gerais-Belo Horizonte, Brazil. silviomusman@yahoo.com.br

Abstract

OBJECTIVE:

To test a prediction model for sleep apnea based on clinical and sociodemographic variables in a population suspected of having sleep disorders and submitted to polysomnography.

METHODS:

We included 323 consecutive patients submitted to polysomnography because of the clinical suspicion of having sleep disorders. We used a questionnaire with sociodemographic questions and the Epworth sleepiness scale. Blood pressure, weight, height, and SpO2 were measured. Multiple linear regression was used in order to create a prediction model for sleep apnea, the apnea-hypopnea index (AHI) being the dependent variable. Multinomial logistic regression was used in order to identify factors independently associated with the severity of apnea (mild, moderate, or severe) in comparison with the absence of apnea.

RESULTS:

The prevalence of sleep apnea in the study population was 71.2%. Sleep apnea was more prevalent in men than in women (81.2% vs. 56.8%; p < 0.001). The multiple linear regression model, using log AHI as the dependent variable, was composed of the following independent variables: neck circumference, witnessed apnea, age, BMI, and allergic rhinitis. The best-fit linear regression model explained 39% of the AHI variation. In the multinomial logistic regression, mild apnea was associated with BMI and neck circumference, whereas severe apnea was associated with age, BMI, neck circumference, and witnessed apnea.

CONCLUSIONS:

Although the use of clinical prediction models for sleep apnea does not replace polysomnography as a tool for its diagnosis, they can optimize the process of deciding when polysomnography is indicated and increase the chance of obtaining positive polysomnography findings.

Source

Department of Physiology, The University Sleep Disorders Center, College of Medicine and the Center of Excellence in Biotechnology Research, King Saud University, Riyadh, Saudi Arabia.

Abstract

PURPOSE:

The purpose of this study was to examine the effects of one night of continuous positive airway pressure (CPAP) therapy on oxidative stress (lipid peroxidation) levels and the antioxidant activities of superoxide dismutase (SOD) in hypertensive patients with severe obstructive sleep apnea (OSA).

METHODS:

The study group consisted of 34 hypertensive, non-smoking patients with a mean age of 45.09 ± 11.77 years, body mass index of 37.4 ± 8.4 kg/m(2), apnea hypopnea index of 79.17 ± 31.35/h, and desaturation index of 55.07 ± 27.06/h. Patients included in the study were not on medications that may affect antioxidant activity. Patients spent four nights in the sleep disorder center as follows: night 1, an adaptation night; night 2, a diagnostic night; night 3, CPAP titration night; and night 4, a therapeutic night for CPAP treatment. Blood samples were collected in the morning upon awakening on nights 2 and 4 and were immediately transferred to the laboratory for SOD and lipid peroxidation measurements. Oxidative stress levels were quantified by measuring thiobarbituric acid reactive substances. SOD enzymatic activity was measured using a purely chemical system based on NAD(P)H oxidation.

RESULTS:

Mean SOD concentrations were not significantly different in pre-and post-CPAP treatment (0.22 ± 0.09 vs. 0.22 ± 0. U/ml, respectively). However, CPAP treatment significantly inhibited lipid peroxidation levels (2.81 ± 0.27 vs. 2.47 ± 0.35 mmol/ml, respectively, p < 0.005).

CONCLUSION:

The present study supports the theory that CPAP therapy decreases the levels of oxidative stress in OSA patients but may not affect antioxidant defense.

Sleep Breath. 2011 May 13

Source

Department of Endocrinology and Metabolic Diseases, Leiden University Medical Centre, PO Box 9600, 2300 RC, Leiden, the Netherlands, mvandijk2@lumc.nl.

Abstract

AIMS/HYPOTHESIS:

Decreased sleep duration and/or impaired sleep quality negatively influence glucoregulation. The aim of this study was to assess subjective sleep characteristics in patients with type 1 diabetes, to relate sleep characteristics to long-term glycaemic control and to assess possible risk factors for impaired sleep.

METHODS:

We studied 99 adult patients with type 1 diabetes (55 men, 44 women, duration of diabetes 26.9 ± 1.2 years) and 99 age-, sex- and BMI-matched non-diabetic controls. Subjective sleep characteristics were assessed by validated questionnaires, i.e. Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and the Berlin Questionnaire. Glucoregulation was assessed by HbA(1c) values. Clinical variables were obtained from medical charts. Depression was assessed by the Hospital Anxiety and Depression Scale (HADS). Peripheral polyneuropathy was assessed by neurological examination and quantitative sensory testing.

RESULTS:

Of the patients with type 1 diabetes, 35% had subjective poor sleep quality compared with 20% of the control participants (p = 0.021). A higher proportion of the patients with type 1 diabetes were at increased risk for obstructive sleep apnoea (OSA) (17.2% vs 5.1%, p = 0.012). There was no significant association between individual sleep characteristics and HbA(1c) values. On logistic regression analysis, the HADS depression score, presence of peripheral polyneuropathy, habitual snoring and other sleep disturbances (e.g. hypoglycaemia) were independently associated with poor sleep quality.

CONCLUSIONS/INTERPRETATION:

Adult patients with long-standing type 1 diabetes mellitus have disturbed subjective sleep quality and a higher risk for OSA compared with control participants. Subjective sleep disturbances are part of the complex syndrome of long-standing type 1 diabetes.

Diabetologia. 2011 May 15

Source

CNR-IBIM, Institute of Biomedicine, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension & Division of Nephrology, Reggio Calabria, Italy.

Abstract

Sleep apnoea (SA) is a high priority health problem because it disrupts sleep and reduces quality of life, it is associated with obesity, hypertension, especially resistant hypertension, congestive heart failure, diabetes and it engenders cardiovascular (CV) complications and death. The following types of apnoea can be distinguished: (i) obstructive, (ii) central (i.e. neurally mediated) and (iii) mixed. Obstructive SA (OSA) is characterized by a cessation of airflow caused by occlusion of the oropharyngeal tract and central SA by a transient abolition of the neural drive to respiratory muscles. Mixed apnoea represents a combination of the two forms. SA is one of the most important triggers of high sympathetic activity and it is perhaps the most important non-traditional risk factor underlying the high CV risk of chronic kidney disease (CKD). The high sympathetic activity engenders three intermediate mechanisms, chronic hypertension, left ventricular hypertrophy and arrhythmias, particularly atrial fibrillation, which eventually leads to CV complications and death. SA is common in end-stage renal disease and studies in haemodialysis and peritoneal dialysis patients coherently show that intensive dialysis improves SA in patients with severe sleep disordered breathing. Renal transplantation is in theory the ideal way of correcting SA, because a restored renal function abrogates the uraemic toxicity. In a case-control study, the prevalence of mild and severe SA was almost identical in renal transplant patients as compared to age-, sex- and body mass index-matched healthy subjects, supporting the contention that renal transplantation reverses SA. A study published in this issue of Nephrology, Dialysis Transplantation assesses the association between CKD and SA in symptomatic (snorers) patients, excluding by protocol those with hypertension and diabetes, which are well-known risk factors for SA and CKD. The primary hypothesis tested in this study, i.e. whether snorers are at a higher risk for renal dysfunction, is a sensible one.

Nephrol Dial Transplant. 2011 May 17