Beclin-1 increases with obstructive sleep apnea severity.

Obstructive sleep apnea is a common chronic disorder that leads to chronic intermittent hypoxia described as an important factor contributing to the pathogenesis of OSA-related comorbidities. Besides, recent data suggest that intermittent hypoxia can induce adaptative cardiovascular pathways inducing a relative resistance to ischemic insults. Adaptative pathways induced by hypoxia could implicate autophagic processes and Beclin-1, one of the first mammalian autophagy effectors. Thus, activation of autophagy could protect against cardiovascular events in patients with OSA and could be considered as biomarker of a better prognosis.

OSA treatment with CPAP: Randomized crossover study comparing tolerance and efficacy with and without humidification by ThermoSmart.

OBJECTIVES: Adherence to continuous positive airway pressure (CPAP) remains an issue, as adverse effects (AE) such as rhinitis, dry/congested nose, dry mouth or throat are commonly experienced. The aim of the study was to compare CPAP efficacy and tolerance in severe obstructive sleep apnea (OSA) patients with or without (w/o) heated humidification using the ThermoSmart system. METHODS: Multicenter RCT study in which CPAP-naive patients with severe OSA and meeting one or more of the following criteria: >65 years, using >1 drying medication, previous nasal symptoms or nasal surgery, were included. Patients were randomized to CPAP w/o heated humidification for 1 month and then crossed-over to the other treatment arm for another month. Naso-pharyngeal symptoms, Quality of life (FOSQ-10), sleepiness (ESS) and CPAP compliance and efficacy data were collected. RESULTS: Forty patients were enrolled: age 62 ± 9 years, diagnostic AHI 46.7 ± 15.3/hour. About 70% were using >1 drying medication, mainly antihypertensives. Both treatment modalities were found to normalize AHI and decrease sleepiness with no differences between 2 modes, compliance (4.63 ± 0.39 vs 4.70 ± 0.36 h/night) or leaks (32.4 ± 2.0 versus 31.1 ± 1.7l/min). With heated humidification, there was a significant decrease in nasal symptoms such as dry/congested nose. At the study end, 26 patients preferred ThermoSmart ON, 3 did not have preference and 11 preferred ThermoSmart OFF. CONCLUSION: ThermoSmart helps to decrease nose and throat discomfort because of CPAP therapy, these effects did not translate to better compliance but patients had a preference for ThermoSmart.

Telomere Shortening in Middle-Aged Men with Sleep-disordered Breathing.

RATIONALE: Sleep disorders may lead to stress-induced premature aging and telomere shortening. OBJECTIVES: To determine whether obstructive sleep apnea syndrome causing intermittent hypoxemic episodes was associated with telomere shortening independently from the comorbidities associated with this syndrome. METHODS: We conducted a cross-sectional study in 161prospectivelly enrolled, untreated, middle-aged men free of known comorbidities related or unrelated to sleep apnea. Each participant underwent full standard overnight polysomnography. Patients with apnea sleep syndrome were naive to treatment. MEASUREMENTS AND MAIN RESULTS: In univariate analysis, we found that telomere shortening was associated with older age, apnea-hypopnea index, oxygen desaturation index, waist circumference, and fat mass. After adjustment for age, only apnea-hypopnea index and oxygen desaturation index were significantly related to telomere shortening. The mean telomere length ratio was 0.70 ± 0.37 in the participants without sleep apnea, compared with 0.61 ± 0.22 and 0.53 ± 0.16 in those with mild to moderate and severe sleep apnea, respectively (P = 0.01). In multivariate analysis, we found that oxygen desaturation index was the only factor independently associated with telomere length. Arterial stiffness assessed by carotid-femoral pulse wave velocity correlated negatively with telomere length. CONCLUSIONS: Intermittent hypoxemia due to obstructive sleep apnea syndrome is a major contributor to telomere shortening in middle-aged men. Oxidative stress may explain this finding.

Prevalence, Severity, and Prognostic Value of Sleep Apnea Syndromes in Cardiac Amyloidosis.

STUDY OBJECTIVES: To assess prevalence, severity, and prognostic value of sleep-disordered breathing (SDB), in the three main cardiac amyloidosis (CA) types, i.e., light-chain (AL), transthyretin-related familial (m-TTR), or senile (WT-TTR). METHODS: Patients consecutively referred for CA diagnosis work-up underwent cardiac assessment and nocturnal polygraphy. SDB was defined as apnea-hypopnea index (AHI) ≥ 5/h. Multivariate analysis was used to identify predictors of a major adverse cardiac event (MACE) defined as death, heart transplantation and acute heart failure. RESULTS: Seventy CA patients were included (31 AL, 22 m-TTR, 17 WT-TTR). The mean ± standard deviation age and left ventricular ejection fraction were 71 ± 12 years and 49% ± 13% and median (interquartile range) N terminal pro brain natriuretic peptide (NT-proBNP) was 3,932 (1,607; 7,028) pg/mL. The prevalence of SDB was 90% without difference between amyloidosis types. SDB was central in 27% and obstructive in 73%. AL had less frequent severe SDB compared to m-TTR and WT-TTR (P = 0.015) but longer time with peripheral capillary oxygen saturation (SpO2) < 90% (P = 0.037). After a median follow-up of 7.5 (2.8; 14.9) months, 49% patients experienced MACE. Time with nocturnal SpO2 < 90% was the only independent predictor of MACE. The best-identified threshold was 30 min. Values > 30 min were associated with bad prognosis (Log-rank χ(2): 8.01, P value = 0.005). Using binomial logistic regression, determinants of time with nocturnal SpO2 < 90% were New York Heart Association class (P = 0.011), and log-NT-proBNP (P = 0.04) but not AHI. CONCLUSIONS: In CA population, prevalence of SDB is high (90%) and dominated by the obstructive pattern. Bad prognosis in this population was driven by nocturnal desaturation, reflecting heart failure severity and respiratory involvement.

Apnea-hypopnea and desaturations in heart failure with reduced ejection fraction: Are we aiming at the right target?

BACKGROUND: Sleep disordered breathing (SDB) is common in patients with heart failure with reduced ejection fraction (HFrEF). An increased apnea-hypopnea index (AHI) is associated with poor outcomes. We examined whether an analysis of nocturnal desaturations (NDs) can improve the risk stratification. METHODS: Three-hundred seventy-six consecutive patients with stable chronic HFrEF and LVEF ≤ 45% were prospectively screened using polygraphy. Sleep apnea (SA) was defined as an AHI ≥ 15. The mean age was 59 ± 13 years, the mean LVEF was 30 ± 6%, and the median AHI was 18 [IQR: 9.33). The composite end-point of death, heart transplantation or LV assistance occurred in 98 patients (26%) within 3 years. Minimal oxygen saturation (MOS) during sleep, the number of desaturations <90%/h and the time spent with oxygen saturation <90% were significantly associated with adverse events (adjusted HR 1.25 [1.03-1.52], 1.25 [1.03-1.53], and 1.28 [1.04-1.59]), whereas the AHI was not (1.10 [0.86-1.39]). The best MOS cut-off value for poor outcomes was ≤ 88%. The patients with an MOS ≤ 88% had a significantly higher event rate (31.9%) than those with an MOS >88% (15.6%; p<0.01). The risk assessment using an MOS of ≤ 88% in addition to established prognostic markers yielded a net reclassification index (NRI) of nearly 6% and was particularly useful in the subgroup of patients with events (NRI: 8.4%). CONCLUSIONS: In HFrEF patients, ND ≤ 88% appears to be predictive of adverse events, independent of the presence of SA. This suggests that the risk assessment in HFrEF should also include ND in top of AHI.

Sleep-disordered breathing in chronic heart failure: development and validation of a clinical screening score.

AIMS: Sleep-disordered breathing (SDB) is highly prevalent and of adverse prognostic significance in patients with chronic heart failure (CHF). Polygraphy is used for diagnosing SDB but polygraphy resources fall short of needs. Here, our aim was to develop a score for SDB screening in patients with CHF. METHODS AND RESULTS: Consecutive patients with stable chronic CHF referred to our CHF clinic for a scheduled follow-up evaluation were included prospectively between 2000 and 2012. SDB was defined as an apnoea-hypopnoea index ≥ 5/h as assessed by routine polygraphy. A screening score was developed as a linear combination of factors independently associated with SDB by multivariate logistic regression. Calibration and discrimination were evaluated using the Hosmer-Lemeshow (HL) test and area under the receiver-operating characteristics curve (AUC), respectively. Bootstrapping was performed to assess internal validity. Of 450 included patients (mean age, 59.5 ± 13.7 years), 397 (88%) had SDB. An easy-to-use score was based on age (2 points if ≥65 years), body mass index (2 points if ≥25 kg/m(2)), New York Heart Association (NYHA) class (2 points if ≥3 or 4) and male gender (3 points). A score cut-off of 5 was 78.9% sensitive and 61.5% specific for SDB. The final model exhibited adequate calibration (pHL ≥ 0.3) and discrimination (AUC, 0.737; 95% confidence interval, 0.663; 0.810). CONCLUSION: An easy-to-use clinical score combining age, body mass index, NYHA class, and gender may help to identify those CHF patients most likely to have SDB, thereby improving the allocation of scarce polygraphy resources and early diagnosis of SDB.

Aging-related systemic manifestations in COPD patients and cigarette smokers.

RATIONALE: Chronic obstructive pulmonary disease (COPD) is often associated with age-related systemic abnormalities that adversely affect the prognosis. Whether these manifestations are linked to the lung alterations or are independent complications of smoking remains unclear. OBJECTIVES: To look for aging-related systemic manifestations and telomere shortening in COPD patients and smokers with minor lung destruction responsible for a decline in the diffusing capacity for carbon monoxide (DLCO) corrected for alveolar volume (KCO). METHODS: Cross-sectional study in 301 individuals (100 with COPD, 100 smokers without COPD, and 101 nonsmokers without COPD). MEASUREMENTS AND MAIN RESULTS: Compared to control smokers, patients with COPD had higher aortic pulse-wave velocity (PWV), lower bone mineral density (BMD) and appendicular skeletal muscle mass index (ASMMI), and shorter telomere length (TL). Insulin resistance (HOMA-IR) and glomerular filtration rate (GFR) were similar between control smokers and COPD patients. Smokers did not differ from nonsmokers for any of these parameters. However, smokers with normal spirometry but low KCO had lower ASMMI values compared to those with normal KCO. Moreover, female smokers with low KCO, had lower BMD and shorter TL compared to those with normal KCO. CONCLUSIONS: Aging-related abnormalities in patients with COPD are also found in smokers with minor lung dysfunction manifesting as a KCO decrease. Decreased KCO might be useful, particularly among women, for identifying smokers at high risk for aging-related systemic manifestations and telomere shortening.

Ventricular orexin-A (hypocretin-1) levels correlate with rapid-eye-movement sleep without atonia in Parkinson's disease.

OBJECTIVE: Patients with Parkinson's disease frequently complain of sleep disturbances and loss of muscle atonia during rapid-eye-movement (REM) sleep is not rare. The orexin-A (hypocretin-1) hypothalamic system plays a central role in controlling REM sleep. Loss of orexin neurons results in narcolepsy-cataplexy, a condition characterized by diurnal sleepiness and REM sleep without atonia. Alterations in the orexin-A system have been also documented in Parkinson's disease, but whether these alterations have clinical consequences remains unknown. METHODS: Here, we measured orexin-A levels in ventricular cerebrospinal fluid from eight patients with Parkinson's disease (four males and four females) who underwent ventriculography during deep brain-stimulation surgery and performed full-night polysomnography before surgery. RESULTS: Our results showed a positive correlation between orexin-A levels and REM sleep without muscle atonia. CONCLUSION: Our results suggest that high levels of orexin-A in Parkinson's disease may be associated with loss of REM muscle atonia.

Daily administration of the TP receptor antagonist terutroban improved endothelial function in high-cardiovascular-risk patients with atherosclerosis.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: • Terutroban is a selective TP receptor antagonist, i.e. a specific antagonist of the thromboxane A(2) and prostaglandin endoperoxide receptors, shown to improve endothelial function after a single administration in patients with coronary artery disease. WHAT THIS STUDY ADDS: • This randomized, double-blind, placebo-controlled trial demonstrates that repeated-dose terutroban for 15 days improves endothelial function and inhibits thromboxane A(2) -induced platelet aggregation in high-cardiovascular-risk patients taking 300 mg of aspirin per day. Terutroban may prove useful for preventing cardiovascular events in such patients. AIMS: The specific TP receptor antagonist terutroban improves endothelial function after a single dose in patients with coronary artery disease. Our aim was to evaluate the effects and dose dependency of repeated-dose terutroban on endothelial function and platelet aggregation in high-cardiovascular-risk patients with carotid atherosclerosis. METHODS: We randomly allocated 48 patients taking 300 mg aspirin per day to placebo or to one of three terutroban dosages (2.5, 5 or 10 mg) for 15 days in a double-blind study. Flow-mediated vasodilatation was evaluated before and 2 h after the first oral dose on day 0 and 2 h after the last oral dose on day 14. RESULTS: On day 0 and day 14, all three terutroban dosages improved flow-mediated vasodilatation and abolished platelet aggregation induced by the TP receptor agonist U46619, without changing the aggregation response to ADP or collagen. CONCLUSION: Terutroban, by chronically improving endothelium-dependent vasodilatation and inhibiting platelet aggregation, may prove useful for preventing cardiovascular events in high-risk patients.

Effects of polycythemia on systemic endothelial function in chronic hypoxic lung disease.

Chronic obstructive pulmonary disease (COPD) is a major risk factor for cardiovascular disease. Polycythemia, a common complication of hypoxic COPD, may affect systemic vascular function by altering blood viscosity, vessel wall shear stress (WSS), and endothelium-derived nitric oxide (NO) release. Here, we evaluated the effects of hypoxia-related polycythemia on systemic endothelial function in patients with COPD. We investigated blood viscosity, WSS, and endothelial function in 15 polycythemic and 13 normocythemic patients with COPD of equal severity, by recording brachial artery diameter variations in response to hyperemia and by using venous occlusion plethysmography (VOP) to measure forearm blood flow (FBF) responses to a brachial artery infusion of acetylcholine (ACh), bradykinin (BK), sodium nitroprusside (SNP), substance P (SP), isoptin, and N-monomethyl-L-arginine (L-NMMA). At baseline, polycythemic patients had higher blood viscosity and larger brachial artery diameter than normocythemic patients but similar calculated WSS. Flow-mediated brachial artery vasodilation was increased in the polycythemic patients, in proportion to the hemoglobin levels. ACh-induced vasodilation was markedly impaired in the polycythemic patients and negatively correlated with hemoglobin levels. FBF responses to endothelium- (BK, SP) and non-endothelium-dependent (SNP, isoptin) vasodilators were not significantly different between the two groups. L-NMMA infusion induced a similar vasoconstrictor response in both groups, in accordance with their similar baseline WSS. In conclusion, systemic arteries in polycythemic patients adjust appropriately to chronic or acute WSS elevations by appropriate basal and stimulated NO release. Overall, our results suggest that moderate polycythemia has no adverse effect on vascular function in COPD.