Continuing professional development:introducing the ERS International Certificate in Respiratory Sleep Medicine

Certification of specialists in respiratory sleep medicine for the purposes of continuing professional developmen

Reticulocytes in untreated Obstructive Sleep Apnoea

Background and Aim. The short, repetitive hypoxaemic episodes observed in obstructive sleep apnoea (OSA) may determine small augmentations in mature red blood cells. It is unknown whether they affect reticulocyte release. This study explored whether the number and degree of maturation of circulating reticulocytes may be altered in OSA, possibly through the effect of erythropoietin. Methods. Fifty male adult patients with suspected OSA, normoxic during wakefulness, were studied. After nocturnal polysomnography, a blood sample was withdrawn for blood cells count, erythropoietin, iron and transferrin determination. Reticulocyte concentration and degree of immaturity [high (H), medium (M), or low (L)] were also determined. Immature reticulocyte fraction (IRF) was calculated as (M+H) percentage of reticulocytes. Results. A wide range of OSA severity was found [apnoea/ hypopnoea index (AHI): 44.3±30.4, range 0.3-105; sleep time spent at oxyhaemoglobin saturation 2% had higher EPO levels (p<0.05), but not worse nocturnal desaturations, than those with values <2%. By contrast, subjects with IRF <15% showed worse desaturations (p<0.05), but similar EPO concentrations, when compared to subjects whose IRF was <10%. At univariate analysis, reticulocyte count correlated to erythropoietin, while IRF to transferrin saturation, BMI and OSA severity. At multiple regression, only lowest nocturnal oxygen saturation remained a significant contributor to IRF (r2 0.223, p<0.05). Conclusions. This data suggests that hypoxaemia due to OSA could influence the release of immature reticulocytes, but this effect is not mediated by erythropoietin

Obstructive sleep apnea and blood pressure in young hypertensives: does it matter?

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Airway inflammation in patients affected by obstructive sleep apnea syndrome

AbstractObstructive sleep apnea syndrome (OSAS) has been shown to be associated to upper airway inflammation. The object of the present study was to establish the presence of bronchial inflammation in OSAS subjects.In 16 subjects affected by OSAS, and in 14 healthy volunteers, airway inflammation was detected by the cellular analysis of the induced sputum.OSAS patients, as compared to control subjects, showed a higher percentage of neutrophils (66.7±18.9 vs. 25.8±15.6) (P<0.001) and a lower percentage of macrophages (29.4±18.4 vs. 70.8±15.3) (P<0.001). The percentage of eosinophils and lymphocytes were not significantly different in the two groups.OSAS subjects show bronchial inflammation characterized by a significant increase in neutrophils

Abnormal thyroid hormones and non-thyroidal illness syndrome in obstructive sleep apnea, and effects of CPAP treatment.

Abstract OBJECTIVE: In obstructive sleep apnea (OSA), while both hypothyroidism and hyperthyroidism have been studied, the occurrence of non-thyroidal illness syndrome (NTIS) (normal thyroid stimulating hormone [TSH] with low triiodotironine) has not been investigated. We explored the occurrence of NTIS in patients with moderate to severe OSA and its relationship to the severity of nocturnal respiratory disorders. We also studied the occurrence of subclinical hypothyroidism (SH, ie, high TSH with normal thyroxine) in OSA and changes in circulating TSH, free triiodotironine (fT3) and free thyroxine (fT4) after CPAP treatment. METHODS: After a nocturnal respiratory polysomnography, 125 consecutive patients with moderate to severe OSA and 60 control subjects with normal nocturnal respiration were recruited. Morning circulating TSH, fT3, and fT4 were measured in all subjects. In a subsample of patients, nocturnal polysomnography and hormonal determinations were repeated after CPAP treatment for five months. RESULTS: NTIS was found in 13 (10.4%), and SH in ten (8%) OSA subjects, but not in any control subjects. Patients with NTIS showed worse mean nocturnal oxygen saturation and time with saturation <90% (both p < 0.001). After treatment, NTIS subjects (n = 13) showed an increase in fT3 (p < 0.001) to the normal range, and SH subjects (n = 6) a slight decrease in TSH (p = 0.01). In the patients with normal hormones before treatment (n = 45), no change was observed. CONCLUSIONS: NTIS may occur in OSA patients with severe nocturnal hypoxemia. OSA treatment is followed by an improvement in TSH in patients with abnormal baseline levels of this hormone, and by recovery of NTIS

Supplementary Material for: Cardiovascular Events in Moderately to Severely Obese Obstructive Sleep Apnea Patients on Positive Airway Pressure Therapy

<p><b><i>Background:</i></b> In moderately to severely obese patients with obstructive sleep apnea (OSA), the effects of long-term positive airway pressure (PAP) treatment on cardiovascular risk are poorly defined. <b><i>Purpose:</i></b> To assess the effect of continuous positive airway pressure (CPAP) or noninvasive ventilation (NIV) on the occurrence of cardiovascular events in obese OSA patients. <b><i>Methods:</i></b> We performed a noninterventional observational study in obese OSA patients recruited between 2007 and 2010 at the Sleep Center, University of Grenoble, treated with CPAP or NIV, and followed for 5.6 years by a single home care provider. Baseline clinical characteristics, blood chemistry, and respiratory and vascular function were assessed. Incident cardiovascular events were investigated by phone interviews. <b><i>Results:</i></b> A total of 103 patients (55 men, 48 women; age and body mass index [BMI] at diagnosis 54.1 ± 10.5 years and 40.3 ± 5.5, respectively [mean ± standard deviation]; CPAP: <i>n</i> = 75; NIV: <i>n</i> = 28) agreed to participate in the study. Grade I, II, and III obesity occurred in 17.5, 33.0, and 49.5% of the sample, respectively. In patients using PAP treatment (<i>n</i> = 69), the mean nightly use was 6.3 ± 2.4 h. Thirty-one patients stopped PAP treatment during follow-up. Three patients on NIV died. Nonfatal cardiovascular events (<i>n</i> = 27) occurred in 19 patients, who were older and showed higher number of comorbidities and triglyceride levels than patients without events. In the patients who interrupted treatment, the event rate was high and increased with the number of comorbidities, while BMI at baseline did not predict events. <b><i>Conclusions:</i></b> The study suggests that regular PAP treatment may be associated with protection against cardiovascular risk in obese OSA patients, especially in the presence of multiple comorbidities.</p