Objective: Obstructive sleep apnoea syndrome (OSAS) associated with daytime sleepiness (DS) contributes to a higher incidence of motor vehicle accidents. Validation of fitness to drive in driving license applicants, with special concern regarding OSAS accompanied by excessive DS, became mandatory under new EU legislation in January 2016. The aim of the study was to translate and validate the recommended questionnaire to screen for OSAS (Q-OSAS) in the Slovak population. No data on any Q-OSAS validation has previously been published.Methods: The translated Q-OSAS was administered to 311 Slovak patients prior to a planned overnight polysomnography. The diagnostic accuracy of the Q-OSAS in OSAS with an apnoea-hypopnoea index of 15 or more/h of sleep was evaluated by calculating the area under the ROC curve.Results: The sensitivity and specificity of the cut-off at 10 points for the Q-OSAS was 57% and 67%, respectively, with an increase of sensitivity and a decrease of specificity with a lowering of the cut-off values. Excluding the Epworth Sleepiness Scale (ESS) score from the final statistics yielded the best sensitivity (77%), specificity (50%), and an area under the ROC curve (0.637) for the cut-off value of 8 points (an equivalent of 10 points with the full version of the Q-OSAS). Conclusion:The Q-OSAS is an appropriate screening tool to facilitate the screening of subjects potentially at risk from moderate and severe OSAS. A modified two-step interpretation of the Q-OSAS in Slovakia yielded the best sensitivity, and in the future could promote evaluation of sleepiness in sleep and wake disorders other than OSAS for fitness to drive.

Circulating lipopolysaccharide-binding protein (LBP), a metabolic endotoxemia marker, was identified as an independent predictor of atherosclerosis. Although increases in carotid intima-media thickness (CIMT) were repeatedly reported in obstructive sleep apnea (OSA), neither the role of OSA in metabolic endotoxemia nor of LBP in early atherosclerosis were explored in patients with OSA. At a tertiary university hospital we investigated the relationships between OSA, LBP and CIMT in 117 men who underwent full polysomnography and CIMT assessment by B-mode ultrasound. Circulating LBP concentrations and average CIMT increased from patients without OSA to those with mild-moderate and severe OSA (from 32.1±10.3 to 32.3±10.9 to 38.1±10.3 μg.ml-1, p=0.015; from 0.52±0.09 to 0.58±0.06 to 0.62±0.10 mm, p=0.004, respectively). Oxygen desaturation index (ODI) was a predictor of serum LBP levels independent of age, waist-to-hip ratio (WHR), smoking, hypertension, HDL cholesterol, triglycerides and fasting glucose [p (ANOVA)=0.002, r2=0.154], with no independent effect of the ODI*WHR interaction term on LBP. Furthermore, serum LBP predicted CIMT independently of known risk factors of atherosclerosis including obesity (p<0.001, r2=0.321). Our results suggest that OSA severity contributes to metabolic endotoxemia in patients with OSA independently of obesity, and that LBP might represent a contributing factor promoting early atherosclerosis in such patients.

AimTo assess the effects of single nucleotide polymorphisms (SNPs) on blood pressure control in patients with obstructive sleep apnea (OSA).MethodsThis prospective observational cohort study, conducted between 2004 and 2014, examined the associations of SNPs of JAG1, GUCY1A3-GUCY1B3, SH2B3, and NPR3-C5orf23 genes with systolic and diastolic blood pressure (SBP, DBP) in 1179 adults evaluated for OSA with overnight polysomnography. Genotyping was performed by unlabeled probe melting analysis.ResultsThe patients were predominantly male (69.6%, mean age 52 ± 11 years, apnea-hypopnea index 34 ± 31 episodes/h). Only JAG1 genotype was associated with SBP and DBP: compared with AA homozygotes, G allele carriers (pooled GG and AG genotype) had significantly higher morning SBP (132 ± 19 vs 129 ± 18 mm Hg; P = 0.009) and morning and evening DBP (85 ± 11 vs 83 ± 10 mm Hg, P = 0.004; 86 ± 10 vs 84 ± 10 mm Hg, P = 0.012, respectively); the differences remained significant after the correction for multiple SNPs testing. In multivariate analyses, oxygen desaturation index and JAG1 genotype independently predicted morning SBP (P = 0.001, P = 0.003, respectively) and DBP (P < 0.001, P = 0.005, respectively), and evening SBP (P = 0.019, P = 0.048, respectively) and DBP (P = 0.018, P = 0.018, respectively).ConclusionThis is the first replication study of the SNPs recently linked to arterial hypertension in general population by genome-wide association studies. Our findings suggest that JAG1 genotype is related to blood pressure control in OSA: G allele was associated with higher morning and evening SBP and DBP.

OBJECTIVE: To evaluate the acute effects of volume-targeted non-invasive ventilation (NIV) on hemodynamic parameters assessed by impedance cardiography in patients with obesity hypoventilation syndrome (OHS). BACKGROUND: Despite the well-described benefi cial effects of NIV using volume-targeted pressure support ventilation modes on respiration in OHS patients, questions were raised about the impact of this treatment on the cardiovascular system. METHODS: In 15 patients (10 men; mean age, 55.8±9.3 years) impedance cardiography recordings were taken at baseline, after 120 minutes while on NIV and 20 minutes after NIV termination. A repeated-measures analysis of variance was used for comparisons. RESULTS: Compared to baseline, a reduction in heart rate (from 80±11 to 73±10 beats per min, p<0.05) was observed on NIV whereas the stroke volume and cardiac index remained stable throughout all three assessed intervals (p=0.347, p=0.344; respectively). The pre-ejection period increased on NIV (from 113±16 to 127±20 ms, p<0.05), and the left ventricular ejection time increased after NIV termination compared to baseline (from 259±25 to 269±25 ms, p<0.05). CONCLUSION: Volume-targeted NIV may acutely improve systolic time intervals without any negative impact on the left ventricular function in OHS patients (Tab. 2, Ref. 17).