No abstract

Background: Obstructive sleep apnea (OSA) is associated with obesity, metabolic syndrome, and dyslipidemia, which may be related to decrease androgen levels found in OSA patients. Dyslipidemia may contribute to atherosclerosis leading to increasing risk of heart disease. Methods: Systematic review was conducted using PubMed and Cochrane library by utilizing different combinations of key words; sleep apnea, obstructive sleep apnea, serum lipids, dyslipidemia, cholesterol, total cholesterol, low density lipoprotein (LDL), high density lipoprotein (HDL), and triglyceride (TG). Inclusion criteria were: English articles, and studies with adult population in 2 groups of patients (patients with OSA and without OSA). A total 96 studies were reviewed for inclusion, with 25 studies pooled for analysis. Results: Sixty-four studies were pooled for analysis; since some studies have more than one dataset, there were 107 datasets with 18,116 patients pooled for meta-analysis. All studies measured serum lipids. Total cholesterol pooled standardized difference in means was 0.267 (p = 0.001). LDL cholesterol pooled standardized difference in means was 0.296 (p = 0.001). HDL cholesterol pooled standardized difference in means was -0.433 (p = 0.001). Triglyceride pooled standardized difference in means was 0.603 (p = 0.001). Meta-regression for age, BMI, and AHI showed that age has signifi cant effect for TC, LDL, and HDL. BMI had signifi cant effect for LDL and HDL, while AHI had signifi cant effect for LDL and TG. S C I E N T I F I C I N V E S T I G A T I O N SO bstructive sleep apnea (OSA) is a common disorder affecting about 4% of middle-aged males and 2% of middle-aged women in the developed world and is a significant source of morbidity and mortality. 1,2 OSA is characterized by recurrent episodes of upper airway collapses during sleep. These recurrent episodes of upper airway collapse usually are accompanied by oxyhemoglobin desaturation and terminated by brief arousals which result in marked sleep fragmentation and chronic excessive daytime sleepiness (EDS). 1,2 OSA has been increasingly linked to cardiovascular and cerebrovascular disease, and many studies have shown that OSA is associated with increased cardiovascular and cerebrovascular morbidity. 3-9 OSA is associated with obesity and metabolic syndrome. 10 Multiple studies addressing this interesting and complex issue are available where lipid profi le was measured in subjects with OSA. We performed metaanalysis (MA) and meta-regression (MR) to specifi cally detect if OSA adversely affects degree of dyslipidemia; elevation of total cholesterol (TC), low density lipoprotein cholesterol (LDL), triglyceride (TG), and reduces level of high density lipoprotein cholesterol (HDL). Effect of Obstructive Sleep Apnea Hypopnea Syndrome on METHODS Data Source and Study SelectionStudies for review were found searching the PubMed, Cochrane, and EMBASE databases from January 01, 196801, , to November 30th, 2013. Unpublished data from scientifi c meetings were not searched, since...

CPAP treatment for OSA seems to improve dyslipidemia (decrease in total cholesterol and LDL, and increase in HDL). It does not appear to affect TG levels.

In patients with sleep-disordered breathing and heart failure, continuous positive airway pressure has been found to be associated with an improvement in cardiovascular end points. We conducted a systematic review of the current literature and a meta-analysis to pool data from 15 published randomized controlled trials. End points analyzed were left ventricular ejection fraction, diastolic blood pressure, systolic blood pressure, heart rate, and mortality. A fixed effects model was used for end points demonstrating homogeneity among included studies, whereas a random effects model was used for end points demonstrating heterogeneity among included studies. A significant improvement in left ventricular ejection fraction was noted with continuous positive airway pressure (mean difference, 5.05%; 95% confidence interval [CI]: 3.72 to 6.38), diastolic blood pressure (mean difference, −1.67; 95% CI: −3.09 to −0.25), and heart rate (mean difference, −5.92; 95% CI: −10.12 to −1.72). No significant changes in mortality (odds ratio, 0.63; 95% CI: 0.40 to 1.00) and systolic blood pressure were noted (mean difference, −6.35; 95% CI: −16.11 to 2.41). The analysis also revealed the need for additional studies to clarify the associations noted and the presence of publication bias with small studies with a paucity of small studies with negative results. In this meta-analysis, treatment with continuous positive airways pressure was associated with improvements in ejection fraction, diastolic blood pressure, and heart rate in patients with sleep-disordered breathing and congestive heart failure.