Putative associations between inflammatory biomarkers, obesity, and obstructive sleep apnea.

BACKGROUND: Previous studies have reported increased levels of inflammatory mediators in patients with obstructive sleep apnea (OSA), but their relation with the severity of OSA is controversial. OBJECTIVE: To address potential relationships between OSA-related inflammatory markers, namely, C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and fibrinogen, with different oxygenation parameters and with BMI. METHODS: All eligible patients with suspected OSA newly referred to the Sleep Medicine Research Center at King Abdulaziz University Hospital, Jeddah, were evaluated demographically and anthropometrically, and underwent overnight polysomnography. Fasting morning blood samples were collected to measure serum levels of CRP, fibrinogen, TNF-α, and IL-6. Potential correlations between these inflammatory mediators and severity measures of OSA and body mass index (BMI) were explored. RESULTS: Sixty-four patients completed the study (40 with OSA and 24 without OSA). Significantly increased levels of CRP, fibrinogen, IL-6, and TNF-α emerged in patients with OSA compared to non-OSA. Significant associations between log CRP and log fibrinogen levels emerged with increasing BMI. However, there was no significant association between any of the inflammatory markers and the severity of OSA based on the apnea/hypopnea index or oxyhemoglobin saturation-derived parameters. CONCLUSIONS: OSA patients exhibit increased levels of inflammatory mediators that do not appear to be associated with polysomnographic measures, but exhibit positive correlation with the degree of adiposity.

The utility of proinflammatory markers in patients with obstructive sleep apnea.

PURPOSE: To evaluate the association of recently diagnosed obstructive sleep apnea (OSA) with TNF-α and IL-6 and to measure the effect of short-term continuous positive airway pressure (CPAP) therapy on these markers. METHODS: A prospective, open-label, controlled trial was conducted among patients referred for diagnostic polysomnography (PSG). After PSG, patients were divided into 3 groups: OSA intervention group (N = 21), OSA control untreated group (N = 19), and non-OSA control group (N = 24). IL-6 and TNF-α levels were measured at baseline and 1 month after intervention. Repeated measures (RM) ANOVA and ANCOVA were used to compare the three groups regarding changes in TNF-α and IL-6 levels by analyzing between-subject and within-subject effects as a function of time and adjusting for significant covariates. RESULTS: At baseline, IL-6 (p = 0.05) and TNF-α (p = 0.04) were significantly higher in the OSA patients than in the non-OSA controls. There was no effect of time either on the TNF-α (p = 0.069) or IL-6 (p = 0.717) after 1 month of CPAP. No interaction effect between group and time was found for either TNF-α (p = 0.240) or IL-6 (p = 0.552) after 1 month of CPAP. There was neither a group effect nor an interaction effect between group and time for either IL-6 or TNF α after adjusting for age, BMI, neck circumference, and AHI. CONCLUSION: This study showed increases in proinflammatory state as illustrated by plasma TNF-α and IL-6 levels among recently diagnosed OSA patients, but there were no changes in these inflammatory markers following 1-month CPAP therapy.

Restless legs syndrome and sleep quality among adult sickle cell disease patients.

OBJECTIVE: The purpose of this study is to determine and compare the prevalence of restless legs syndrome (RLS) between adult patients with sickle cell disease (SCD) and non-SCD anemia. METHODS: This cross-sectional study was conducted from December 2013 to July 2014. Patients with SCD and non-SCD anemia were recruited from a hematology clinic at a large university hospital. Patients with secondary RLS were excluded. Data were collected on demographic features, clinical evaluations, laboratory tests, sleep quality using the Pittsburgh Sleep Quality Index, RLS symptoms using the International Restless Legs Syndrome Study Group Criteria, severity of RLS using the International Restless Leg Syndrome Rating Scale, and daytime sleepiness using the Epworth Sleepiness Scale. RESULTS: The study sample consisted of 44 patients with SCD and 45 with non-SCD anemia. The two groups were comparable in age, gender, body mass index, smoking habit, and comorbidities. Poor sleep quality was found in 63% of the SCD group compared to 53% of the non-SCD group. The prevalence of RLS among SCD group and non-SCD group was 13.6% (6/44) and 8.8% (4/45), respectively. These differences, however, were not statistically significant, p > 0.05. Excessive daytime sleepiness was also similar in both groups, with the rate being 20.5 and 17.8% in the SCD and non-SCD groups, respectively. CONCLUSION: Our study revealed that poor sleep quality and RLS were both common among adult patients with SCD; however, they did not differ significantly from patients with non-SCD anemia.

Prevalence of restless legs syndrome and associated risk factors among middle-aged Saudi population.

BACKGROUND AND AIM: The prevalence of restless legs syndrome (RLS) in the general population ranges from 5 to 15%; however, locally, such data are scarce. The aim of this study was to estimate the prevalence of RLS in the middle-aged Saudi population. METHODS: This was a cross-sectional study that was conducted from February 2013 to June 2013 in Jeddah, Saudi Arabia. The target study population was Saudi school employees. Saudi employees aged 30-60 years were randomly selected and interviewed individually. Trained interviewers completed the Wisconsin Sleep Questionnaire, questions about demographics, the Epworth Sleepiness Scale to measure daytime sleepiness, and questions regarding symptoms of RLS based on the criteria defined by the International Restless Legs Syndrome Study Group (IRLSSG). RESULTS: This survey revealed that 8.4% (95% confidence interval (CI): (7.35-9.45)) of the 2,682 participants (62.5% of them were males) had RLS. There was no age effect on the prevalence of RLS. RLS was found to be significantly associated with other sleep disorders, including excessive daytime sleepiness and habitual snoring. A univariate analysis revealed significant correlation of many factors with the RLS, including gender, consanguinity, snoring, diabetes, hypertension, asthma, chronic bronchitis, and smoking. However, when a multivariate logistic regression analysis performed, RLS continued to be associated with male gender, diabetes, asthma, and habitual snoring only. CONCLUSION: The prevalence of RLS is 8.4%, which is within the range reported by Western studies. However, unlike findings of most studies, RLS significantly affects males more than females. In addition, snoring, asthma, and consanguinity are potential new risk factors for RLS.

Prevalence of chronic obstructive pulmonary disease among smokers attending primary healthcare clinics in Saudi Arabia.

BACKGROUND AND OBJECTIVES: The prevalence of chronic obstructive pulmonary disease (COPD) in Saudi Arabia is unknown. The aim of this study was to estimate the prevalence of COPD among smokers more than 40 years of age attending primary healthcare clinics in Saudi Arabia. SETTING AND DESIGN: A questionnaire was used in a cross-sectional collection of demographic data and other items related to diagnosis of COPD in patients visiting primary healthcare clinics. METHODS: Eligible subjects were current or ex-smokers and aged 40 years or above. Spirometry was performed according to American Thoracic Society criteria. Airflow obstruction was classified according to the 2003 update of the World Health Organization and Global Initiative for Chronic Obstructive Lung Disease criteria. COPD was defined as a ratio less than 0.70 of post-bronchodilator-predicted forced expiratory volume in the first second to forced vital capacity (FEV1/FVC <0.70). RESULTS: Because of incomplete data or poor performance on spirometry, of 1380 subjects eligible for the study, only 501 subjects were eligible for data analysis. Seventy-one patients had an FEV1/FVC ratio <0.70, comprising 14.2% of the study population, of which 95.8% were males. Current smokers comprised 57 (80.3%) subjects. Of the 71 subjects who fulfilled the criteria for COPD diagnosis, none were found to be in COPD stage I; 40 (56.3%) were in stage II and 31 (43.6%) were in stage III of the disease. CONCLUSION: Underdiagnosis of COPD in primary healthcare clinics in Saudi Arabia is common, but its extent is not different from the corresponding data available in the literature for other countries. Use of spirometry as a routine test for all patients older than 40 years of age and with a smoking history can help in early detection and proper diagnosis of COPD, which subsequently will help in implementation of preventive measures.