The relationship between high-sensitivity C-reactive protein levels and the severity of obstructive sleep apnea.
ABSTRACT There is an increased risk of cardiovascular and cerebrovascular events in patients with obstructive sleep apnea (OSA). High-sensitivity C-reactive protein (hs-CRP) is a marker that predicts atherosclerotic complications. However, there are contradictory results about the correlation between serum hs-CRP levels and OSA severity. The purpose of this work was to evaluate the relationship between hs-CRP levels and the severity of OSA in newly diagnosed OSA patients.
The study group was composed of 76 patients with clinical suspicion of OSA. Subjects with body mass indexes (BMI) ≥30 kg/m(2) were classified as obese. Full-night polysomnography (PSG) was performed on all patients. Patients with an apnea-hypopnea index (AHI) ≥5 were considered to have OSA, and patients with an AHI <5 were accepted as the control group. Blood samples were taken from all patients to analyze serum hs-CRP levels the morning after PSG.
The serum hs-CRP levels were significantly higher in the OSA group (4.03 ± 3.58 mg/L) than in the control group (2.41 ± 1.95 mg/L) (p = 0.013). This high level was positively correlated with BMI (r = 0.376, p = 0.001) and with AHI (r = 0.280, p = 0.014). In multiple regression analysis, elevated hs-CRP levels were associated with AHI (F = 3.293, p = 0.033), which was independent of obesity.
Patients with OSA have elevated serum levels of hs-CRP, a marker for inflammation and an independent risk predictor for cardiovascular morbidity. The severity of OSA is responsible for the elevation of hs-CRP.
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ABSTRACT: The purpose of this systematic review is to evaluate the diagnostic value of biological markers (exhaled breath condensate, blood, salivary and urinary) in the diagnosis of OSA in comparison to the gold standard of nocturnal PSG.Journal of clinical sleep medicine: JCSM: official publication of the American Academy of Sleep Medicine 10/2014; DOI:10.5664/jcsm.4358 · 2.93 Impact Factor
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ABSTRACT: Despite its high prevalence and frequent association with multiple comorbidities, including hypertension, heart disease, and stroke, obstructive sleep apnea (OSA) still lacks appropriate tools for cardiovascular risk assessment and stratification. Circulating biomarkers represent a safe, convenient, and inexpensive possibility, and several studies have been performed to define an ideal marker in this context. Additionally, biomarkers can provide insight into the pathological mechanisms of the disease and suggest new therapeutic approaches. In the present review, the authors critically analyze the biomarkers of cardiovascular risk currently available and other potential markers, including brain natriuretic peptide, C-reactive protein, tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), cysteine, homocysteine, free fatty acids, 8-isoprostane, gamma-glutamyl transferase, glycated hemoglobin, adipokines, and adhesion molecules. The results clearly demonstrate that the relationship between specific biomarkers and OSA is often influenced by age, gender or ethnicity, which has hindered the identification of a unique marker for the evaluation of all patients with OSA. Moreover, given the frequency of comorbidities in OSA, which, by themselves, increase the cardiovascular risk, all confounding factors must be considered in the evaluation of these biomarkers.
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ABSTRACT: Obstructive sleep apnea syndrome (OSAS) is characterized by recurrent episodes of upper airway collapse associated with oxygen desaturation and sleep disruption. It is proposed that these periodic changes lead to molecular variations that can be detected by assessing serum biomarkers. Studies have identified inflammatory, oxidative, and metabolic perturbations attributable to sleep-disordered breathing. Given that OSAS is associated with increased cardiovascular and cerebrovascular morbidity, the ideal biomarker should enable timely recognition with the possibility of intervention. There is accumulating data on the utility of serum biomarkers for the evaluation of disease severity, prognosis, and response to treatment. However, current knowledge is limited by data collection techniques, disease complexity, and potential confounding factors. The current paper reviews the literature on the use of serum biomarkers in OSAS. It is concluded that the ideal serum biomarker still needs to be discovered, while caution is needed in the interpretation of hitherto available results.01/2014; 2014:930535. DOI:10.1155/2014/930535