nCPAP Treatment Research Articles

Lymphocyte Activation as a Possible Measure of Atherosclerotic Risk in Patients with Sleep Apnea

Obstructive sleep apnea (OSA), a breathing disorder in sleep characterized by intermittent hypoxia and sleep fragmentation, constitutes an independent risk factor for cardiovascular morbidity. Investigating how this breathing disorder modulates immune responses may facilitate understanding one of the risk factors for atherosclerosis. T cells play a significant role in atherogenesis and plaque development via cytokine production and by directly contributing to vascular injury. Using flow cytometry and chromium release assays, we found that CD4 and CD8 T cells of OSA patients undergo phenotypic and functional changes and acquire cytotoxic capabilities. Thus, a shift in CD4 and CD8 T cells toward type 2 cytokine dominance with increased IL-4 expression was noted. IL-10 expression in T cells was negatively correlated with the severity of OSA, as determined by the apnea-hypopnea index (AHI), whereas TNF-alpha was positively correlated. CD8 T cells of OSA patients expressed a fourfold increase in TNF-alpha and CD40 ligand (CD40L), and exhibited an increased OSA severity-dependent cytotoxicity against endothelial cells. The percentage of CD4(+)CD28(null) and cytotoxicity of CD4 T lymphocytes were also significantly higher in OSA patients than in controls. Nasal continuous positive airway pressure (nCPAP) treatment, which ameliorated the severity of OSA, significantly lowered TNF-alpha and CD40L expression, and decreased cytotoxicity in CD8 T cells. In conclusion, increased cytotoxicity and cytokine imbalance in CD4 and CD8 T cells may be involved in atherogenesis in OSA. Nasal CPAP treatment ameliorates some lymphocyte dysfunctions and thus may moderate some atherogenic pathways.

Short-term effects of nCPAP on nasal mucociliary clearance and mucus transportability in healthy subjects

Nasal mucociliary clearance is a primary defense mechanism of the upper airways and may be acutely affected by nasal continuous positive airway pressure (nCPAP). nCPAP treatment is effective and safe. However, it can cause nasal side effects and contribute to a low compliance to the treatment. The aim of this study was to investigate the short-term effects of nCPAP on nasal mucociliary clearance and on mucus transportability of healthy subjects. Eleven healthy subjects were submitted to 20 min of nCPAP (10 cm H2O). Five subjects were also evaluated before and after 20 min of rest on the consecutive study day. Nasal mucociliary clearance was measured by the saccharin nasal transit time test and nasal mucus was collected for the in vitro study of mucus transportability by the frog palate model, both before and after the nCPAP challenge. Saccharin nasal transit time decreased significantly after nCPAP (9.29+/-6.06 min and 4.83+/-5.57 min; P=0.002 before and after nCPAP respectively). No significant changes were observed on the control day (11.66+/-7.57 min and 12.40+/-5.62 min; P=0.70). Mucus transportability was not significantly affected by nCPAP. Our results suggest that nCPAP can acutely increase nasal mucociliary clearance but does not affect in vitro mucus transportability in healthy subjects.

Low Plasma Orexin-A Levels Were Improved by Continuous Positive Airway Pressure Treatment in Patients With Severe Obstructive Sleep Apnea-Hypopnea Syndrome

We have previously shown that plasma levels of orexin-A, a neuropeptide with an arousal-stimulating action, were decreased in parallel with the severity of the disease in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). To clarify the effects of nasal continuous positive airway pressure (nCPAP) treatment on plasma orexin-A levels in patients with this syndrome. Sleep tests and blood sample collections were conducted at the sleep-related respiratory disorders clinic and the sleep laboratory of the Iwate Medical University Hospital. We studied 27 patients with OSAHS (apnea-hypopnea index [AHI], >/= 20 by polysomnography) who were treated with nCPAP for 3 to 6 months. These patients were divided into the following two groups according to the arousal index (AI): group A (n = 11), >/= 60; group B (n = 16), < 60. Plasma samples were obtained before and after the nCPAP treatment for 3 to 6 months. Plasma immunoreactive (IR)-orexin-A concentrations were measured by radioimmunoassay after the extraction using cartridges. Plasma IR-orexin-A concentrations were inversely correlated with the AI (r = -0.807; p < 0.0001) and AHI (r = -0.661; p < 0.0001) in 27 patients before the nCPAP treatment. Mean (+/- SEM) plasma IR-orexin-A concentrations were significantly lower in group A (1.0 +/- 0.3 pmol/L) than in group B (4.6 +/- 0.4 pmol/L). Mean plasma IR-orexin-A concentrations were significantly increased after the nCPAP treatment in group A (to 3.4 +/- 1.2 pmol/L; p = 0.0069), whereas they were not significantly changed in group B. The increases in plasma IR-orexin-A concentrations after the nCPAP treatment were in parallel with the improvements in AI and Epworth sleepiness scale (a marker of severity of daytime excessive sleepiness) score in group A. The low plasma orexin-A levels were increased by the nCPAP treatment in patients with severe OSAHS, suggesting that orexin-A is a plasma marker that reflects the severity of OSAHS and the response to treatment.

Septicemia in the First Week of Life in a Norwegian National Cohort of Extremely Premature Infants

To investigate the incidence, causes, predictors, and outcomes of septicemia in the first week of life in a national cohort of extremely premature infants. A prospective study of survival of all infants with gestational age of <28 weeks or birth weight of <1000 g who were born in Norway in 1999-2000 was performed. Data on the maternal prenatal history, delivery, and neonatal course, including detailed information on episodes of microbiologically verified septicemia, were collected on predefined forms. Septicemia was reported in 2 groups, ie, episodes diagnosed on the day of delivery (ie, very early-onset septicemia [VEOS]) and episodes diagnosed from day 2 to day 7 of life (ie, early-onset septicemia [EOS]). Logistic regression models were used for the selection of variables for predictor analysis in each group. Of 462 included infants, VEOS occurred for 15 (32.5 per 1000 population) and EOS for 15 (35.5 per 1000 population). The most prevalent bacteria were Escherichia coli in VEOS (n = 9) and staphylococci (coagulase-negative staphylococci and Staphylococcus aureus) (n = 15) in EOS. Case fatality rates were 40% and 13%, respectively. Independent predictive factors for VEOS were clinical chorioamnionitis (odds ratio [OR]: 10.5; 95% confidence interval [CI]: 3.3-33.4) and high maternal age (OR: 1.2; 95% CI: 1.0-1.3), whereas not receiving systemic antibiotic therapy within 2 days of age (OR: 13.6; 95% CI: 3.7-50.2) and receiving nasal continuous positive airway pressure (n-CPAP) support at 24 hours of age (OR: 9.8; 95% CI: 2.5-38.4) independently predicted septicemia after the first day of life. Whereas vertically transmitted septicemia was dominated by Gram-negative bacteria, with predictors being exclusively of maternal origin, EOS was dominated by typically nosocomial flora, with n-CPAP treatment at 24 hours of age being a powerful predictor. Early n-CPAP treatment, as opposed to mechanical ventilation, as a powerful predictor of septicemia in the early neonatal period, even with adjustment for early systemic antibiotic treatment, is a new observation among extremely premature infants that warrants additional study.

Adiponectin in Patients with Obstructive Sleep Apnea Syndrome: Course and Physiological Relevance

Background: Adiponectin is an adipocyte-derived hormone with anti-inflammatory and insulin-sensitizing properties. Insulin resistance is a typical feature of the obstructive sleep apnea syndrome (OSAS). Objectives: Since nasal continuous positive airway pressure (nCPAP) treatment improves insulin sensitivity in patients with OSAS, we investigated serum adiponectin levels before and during nCPAP treatment to clarify possible interactions between the adiponectin levels and insulin sensitivity in patients with OSAS. Methods: Thirty nondiabetic, obese patients with OSAS (mean age 56.4 ± 11.1 years; apnoea-hypopnoea index (AHI) 46.03 ± 19.57) underwent CPAP treatment. Adiponectin levels and the levels of proinflammatory cytokines and proteins reflecting platelet activation [regulated on activation normally T cell expressed and secreted (RANTES) and soluble P-selectin (sCD62p)], as well as the insulin sensitivity index were measured before, and after 2 days and 3 months of CPAP treatment. Results: Insulin sensitivity increased significantly under nCPAP treatment, whereas adiponectin levels decreased after 2 days of nCPAP treatment, but returned to baseline levels after 3 months of nCPAP treatment. The increase in insulin sensitivity was more pronounced in patients with the highest adiponectin levels at baseline (p = 0.021) after adjustment for body fat (p = 0.003). During treatment, changes in adiponectin levels were highly predictable by the insulin sensitivity index. Conclusions: We found a significant relation between adiponectin and the insulin sensitivity index in overweight patients with OSAS. The lack of a long-lasting change in adiponectin may be explained by the overwhelming influence of the body mass index on adiponectin secretion, which was unchanged during nCPAP treatment.

Effect of nasal continuous positive airway pressure in uncontrolled nocturnal asthmatic patients with obstructive sleep apnea syndrome

The mechanisms of nocturnal asthma are intimately related to circadian rhythms, which influence inflammatory cells and mediators, hormone levels and cholinergic tone. Nocturnal airway narrowing in asthma is sometimes associated with sleep disorders, such as obstructive sleep apnea syndrome (OSAS). The aims of this study were to evaluate the association of nocturnal asthma and OSAS, and investigate the influence of continuous positive airway pressure (CPAP) therapy to improve nighttime symptoms in asthmatic patients with OSAS. Forty-three asthmatic patients who had nocturnal symptoms in spite of the optimal medical treatment according to the Global Initiative for Asthma guidelines and associated with snoring were studied. Pulmonary function tests (PFTs), asthma nighttime symptom scores, and polysomnography were performed on all patients. We treated the patients with an apnea-hypopnea index (AHI) 15 (moderate-severe OSAS) (n=16) with CPAP during 2 months. After 2 months, PFT, asthma nighttime symptom scores were reperformed. There was no significant difference in PFT values before and after CPAP treatment in OSAS patients. Asthma nighttime symptom scores were improved significantly (P<0.05) after CPAP treatment. In conclusion, in some patients with nocturnal asthma, OSAS may be responsible disease for nocturnal symptoms. In this condition, CPAP improves nocturnal symptoms without amelioration in PFT abnormalities.

Resistant hepatic hydrothorax: a successful case with treatment by nCPAP

Hepatic hydrothorax is defined as pleural effusion with liver cirrhosis but no primary cardiopulmonary disease. Hepatic hydrothorax is often resistant to various therapeutic interventions. The most likely cause is the transfer of ascites fluid from the abdomen to the pleural space via the diaphragm because of a negative intrathoracic pressure gradient. A 62-year-old man was diagnosed with hepatoma and cirrhosis. After a partial hepatectomy, he suffered with hepatic hydrothorax. He had snoring without obvious sleep apnea. The patient's hepatic hydrothorax markedly improved following nasal continuous positive airway pressure (nCPAP) treatment during sleep. The mechanism for the improvement may have been the intrathoracic positive pressure during sleep induced by the nCPAP treatment during sleep. nCPAP treatment may provide a new therapy for resistant hepatic hydrothorax.

Corrected QT Dispersion and Cardiac Sympathetic Function in Patients With Obstructive Sleep Apnea-Hypopnea Syndrome

Hypoxemia increases corrected QT dispersion (QTcD), which is the difference between the maximum and minimum QT intervals and is a strong risk factor for cardiovascular mortality. The aim of this study was to investigate the QTcD in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), and the relationship between the QTcD and (123)I-metaiodobenzylguanidine (MIBG) cardiac imaging, which reflects cardiac sympathetic activity. A university hospital. Forty-eight OSAHS patients without cardiac diseases (mean [+/- SD] age, 45.9 +/- 10.8 years; apnea-hypopnea index [AHI] 51.9 +/- 18.5 events per hour) who underwent polysomnography before treatment and on the first night of nasal continuous positive airway pressure (nCPAP) treatment. Before and after nCPAP treatment was started, we measured the QTcD with computer software, before, during, and after sleep, as well as the washout rate of the MIBG administered for cardiac imaging. As a control, QTcD was also measured in the morning from 26 healthy subjects. Before treatment, the mean QTcD during sleep (65.0 +/- 14.6 ms) was greater than that before sleep (57.0 +/- 13.5 ms; p < 0.0001). Meanwhile, after 1 night of nCPAP therapy, the QTcD during sleep (50.6 +/- 11.4 ms) decreased from that before treatment (p < 0.0001) and was smaller than the QTcD before sleep (56.2 +/- 13.3 ms; p = 0.003). Before treatment, the QTcD during sleep correlated with the AHI (r = 0.38; p = 0.009) and the percentage of time that SaO(2) was < 90% (SaO(2) < 90% time) [r = 0.34; p = 0.018]. The QTcD did not correlate with the body mass index or the washout rate of MIBG. However, the washout rate of MIBG correlated with the AHI and the SaO(2) < 90% time. Nocturnal QTcD is increased in OSAHS patients but is decreased by nCPAP therapy independently of cardiac sympathetic function.

Wrist-actigraphic estimation of sleep time under nCPAP treatment in sleep apnoea patients.

The aim of this study was to correlate daily use of nasal continuous positive airway pressure (nCPAP) with total sleep time (TST) evaluated by home actigraphy. Actigraphy was validated by comparing TST determined by actigraphy (aTST) and polysomnography (pTST) in 24 untreated patients with suspected sleep apnoea. The % sleep time spent under nCPAP was estimated on 3 consecutive days in 28 patients receiving long-term nCPAP, by comparing machine-use periods with sleep periods identified by home actigraphy. The mean difference between pTST and aTST was 2.5 min. The correlation coefficient between aTST and pTST was 0.90. Daily use of nCPAP over the 3 study days was 388 +/- 114 min. nCPAP was used 41-100% (82 +/- 17% (mean +/- sD)) of sleep time detected by actigraphy. Some patients used nCPAP during nonsleep periods. In conclusion, comparison of nasal continuous positive airway pressure use with sleep time estimated by home actigraphy shows marked individual differences in the % sleep time under nasal continuous positive airway pressure. These results suggest that actigraphic estimation of sleep time under nasal continuous positive airway pressure could provide a better index than simple daily use of the device to evaluate the impact of treatment in sleep apnoea.

Response Shift in Perception of Sleepiness in Obstructive Sleep Apnea-Hypopnea Syndrome Before and After Treatment with Nasal CPAP

After nasal continuous positive airway pressure (nCPAP) treatment, several symptoms such as hypersomnolence, daytime fatigue, and impaired concentration improve in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). A variability of perception of pretreatment sleepiness (response-shift phenomenon) experienced in OSAHS patients before and after nCPAP treatment may reflect informative shifts in an individual's internal standards, in values and priorities, or in the conceptualization of perceived sleepiness. The objective of this study is to determine whether there is a response shift in perceptions of pretreatment sleepiness before and after nCPAP treatment in patients with OSAHS. We investigated the response shift in Epworth Sleepiness Scale scores before and after nCPAP. Thirty-one consecutive OSAHS patients filled out the subjective ESS before nCPAP treatment (Pre-ESS). After a mean of about 10 months of nCPAP treatment, the patients filled out the ESS again, which was designated as the Post-ESS. Then they were asked to complete the scale again, recalling sleepiness before nCPAP treatment (Response Shift-Pre-ESS). The control group consisted of 11 patients with OSAHS who had not yet received nCPAP treatments and were matched for age, body mass index, and respiratory disturbance index. University Hospital in, Japan. N/A. There was a significant response shift in ESS scores before and after nCPAP treatment (Pre-ESS: 8.5 [95% Confidence interval [CI], 7.1-9.9] vs Response Shift-Pre-ESS: 11.1 [95% CI, 9.5-12.8], P < .002). A significant number of patients (P < .02) had not recognized the degree of sleepiness experienced before treatment until after they had received nCPAP treatment. Eight had pretreatment ESS scores > or = 11 and 18 had posttreatment ESS scores > or = 11 on the Response Shift-Pre-ESS. In the control group, ESS did not change significantly from the first to the second testing performed before nCPAP treatment (first ESS, 8.8 [95% CI, 5.3-12.3]; second ESS, 8.3 [95% CI, 4.7-11.8]: P = .95). Response shifts should be taken into consideration when explaining factors underlying individual differences in susceptibility to daytime sleepiness.

Effects of therapy on the metabolism and humoral factors in patients with obstructive sleep apnea-hypopnea syndrome

The objective of this paper is to investigate the effects of therapy on the metabolism and humoral factors in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). The effects of therapy for OSAHS on multiple risk factors for metabolic and cerebrocardiovascular diseases such as: (i) visceral fat accumulation (VFA) and leptin; (ii) soluble cell adhesion molecules; (iii) liver dysfunction; and (iv) stress proteins are discussed. In patients with moderate and severe OSAHS, nasal continuous positive airway pressure (nCPAP) treatment improved these several risk factors. Nasal continuous positive airway pressure therapy relieves disabling day-to-day symptoms such as hypersomnolence in patients with OSAHS, and improves several factors that are important in the progression of metabolic and cerebrocardiovascular diseases. Therefore, understanding the effects of OSAHS on lifestyle-related diseases, especially the obesity related diseases, is important because of the high prevalence of patients with OSAHS.

Evidence for Lipid Peroxidation in Obstructive Sleep Apnea

Obstructive sleep apnea syndrome (OSA) is associated with an increased rate of cardiovascular morbidity, which has been suggested to be related to oxidative stress. The present study investigated the concentration of lipid peroxidation biomarkers in patients with OSA in comparison with nonapneic controls and the effects of treatment with nasal continuous positive airway pressure (nCPAP) on these biomarkers. In Experiment 1, morning plasma levels of the oxidative-stress biomarkers, thiobarbituric reactive substances (TBARS) and peroxides (PD), and of the antioxidant protective enzyme paraxonase-1 (PON1), were measured in OSA patients with and without cardiovascular disease (CVD) and in nonapneic controls after an overnight fasting. The concentrations of the biomarkers were compared between patients and controls and were correlated with respiratory disturbance index (RDI). In Experiment 2, TBARS and PD were measured at hourly intervals during sleep in sleep-apnea patients before and after nCPAP treatment as well as in controls. In the first experiment, 114 consecutive patients with sleep apnea, 55 without (+OSA/-CVD) and 59 with CVD (+OSA/+CVD), and 30 nonapneic controls were investigated. Nine patients and 6 controls participated in Experiment 2. Five of the patients were also studied 9.3 +/- 3.9 months after nCPAP treatment. Morning levels of TBARS and PD were found to be significantly higher in both groups of OSA patients than in controls. The PON1 was lower in +OSA/+CVD patients than in controls and +OSA/-CVD patients, but the difference between the 2 OSA groups bordered on statistical significance. The concentrations of TBARS and PD were significantly positively correlated with RDI (.43, P < .0001 and .36, P < .0002, respectively), while a negative correlation was found between RDI and PON1 activity (-.24, P < .01). Stepwise regression analysis revealed that RDI was an independent significant predictor of all 3 lipid-peroxidation biomarkers. In the second experiment, nocturnal levels of TBARS and PD were significantly higher in sleep-apnea patients than in controls and were significantly lowered by nCPAP treatment. These results support the existence of an increased state of oxidative stress in OSA and its possible involvement in cardiovascular morbidity.

Effects of nCPAP Treatment over Reaction Time and Sleepiness Levels during Vigilance

Several studies have shown that sleep fragmentation not only increases daytime sleepiness, but also deteriorates reaction time. Obstructive sleep apnea syndrome(OSAS)is characterized by interruptions in normal sleep patterns. Nasal Continuous Positive Airway Pressure(nCPAP)is the most frequently used treatment for OSAS. The objective of this investigation was to evaluate changes in daytime sleepiness levels and reaction time in apnea patients after nCPAP treatments of 1 and 3 months. The sample was composed of 51 obstructive sleep apnea patients(47 men and 4 women)with ages ranging between 30 and 65 years of age. Sleep apnea was diagnosed with a cardiorespiratory polygraph of the total hours of sleep. The Epworth Sleepiness Scale was used to assess daytime sleepiness. A BASIC software program was used to measure the simple perceptual reaction times in milliseconds. The results indicated statistically significant decreases in daytime sleepiness levels at 1 month(p < .000)and at 3 months(p < .000)of treatment. The results also showed statistically significant decreases in reaction times at one month(p < .000), as well as at 3 months(p < .000)of treatment. Results indicate an improvement in the vigilance levels of obstructive sleep apnea patients after 1 month and 3 months of nCPAP treatment.

Sleep-disordered breathing

months after nCPAP treatment. Measurements and Results: Morning levels of TBARS and PD were found to be significantly higher in both groups of OSA patients than in controls. The PON1 was lower in +OSA/+CVD patients than in controls and +OSA/-CVD patients, but the difference between the 2 OSA groups bordered on statistical significance. The concentrations of TBARS and PD were significantly positively correlated with RDI (.43, P < .0001 and .36, P < .0002, respectively), while a negative correlation was found between RDI and PON1 activity (-.24, P < .01). Stepwise regression analysis revealed that RDI was an independent significant predictor of all 3 lipidperoxidation biomarkers. In the second experiment, nocturnal levels of TBARS and PD were significantly higher in sleep-apnea patients than in controls and were significantly lowered by nCPAP treatment. Conclusions: These results support the existence of an increased state of oxidative stress in OSA and its possible involvement in cardiovascular morbidity.

Is nasal continuous positive airway pressure treatment cost effective? Using a standard economic evaluation checklist as a basis for assessment of a cost effectiveness evaluation of nasal continuous positive airway pressure (nCPAP) treatment

The economic evaluation performed by Mar et al. in this article is based on a modelling approach, often used to predict the long term costs and outcomes of treatments when it would be otherwise impractical to conduct extended, empirical, controlled outcomes studies. The semi-Markov model, constructed for the analysis, provides a framework that predicts costs and outcomes for alternative treatment options over both a 5-year and lifetime treatment-time horizon. Its flexible construction enables the authors to test the assumptions made and the data used in the evaluation on the robustness of the study results. 4. Results

NCPAP improves abnormal autonomic function in at-risk-for-SIDS infants with OSA

We evaluated cardiovascular autonomic control and arousability during sleep in infants with obstructive sleep apnea (OSA) before and after 10 +/- 4 (mean +/- SD) days of treatment with nasal continuous positive airway pressure (nCPAP). Six OSA infants and 12 age-matched control infants were studied with polygraphic sleep studies at the age of 13 +/- 4 wk. During the study, 45 degrees head-up tilt tests were performed in slow-wave and rapid eye movement sleep. Blood pressure (BP) and heart rate (HR) were continuously monitored. All OSA infants had decreased initial BP and HR responses, followed by hypotension in two and hypertension in two. OSA infants displayed higher arousal thresholds in response to the tilt in rapid eye movement sleep (P < 0.005) and higher baseline HR (P < 0.05) than controls. nCPAP treatment normalized BP and HR responses as well as arousal thresholds to tilting and stabilized HR levels. OSA in infants may be linked with cardiovascular autonomic control disturbances and decreased arousability during sleep. These defects are improved by control of OSA with nCPAP.

Nasal breathing and continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA).

Although nasal continuous positive airway pressure (nCPAP) treatment is the most efficient therapy for obstructive sleep apnea (OSA), compliance with therapy is poor because of several side effects. Among these adverse effects some are related to the reactions of the nose to nCPAP which are briefly described. In a long-term survey of 109 OSA patients, 80.6% continued nCPAP for at least 3 years until the last follow-up. Follow-up ranged between 0.8 and 109 months with a mean time of 43 (SD +/- 24.7) months. Among all patients treated with nCPAP, only 46.6% met our criteria for long-term compliance, defined as a mean use of the CPAP machine for at least 5 hours per night. Within the objective measures such as age, body mass index, neck circumference, nasal airflow, apnea-hypopnea index, minimal oxygen saturation, and level of nCPAP pressure, no predictive factor for daily use of nCPAP could be found. However, pretherapeutic daytime somnolence (measured by visual analogue scale and Epworth Sleepiness Scale) and its improvement obtained from the therapy showed a significant effect on the daily use of the CPAP machine.

Initiation of CPAP Therapy for OSA: Does Prophylactic Humidification during CPAP Pressure Titration Improve Initial Patient Acceptance and Comfort?

Background: Heated humidifiers (HH) enable effective treatment of upper airway dryness during nasal continuous positive airway pressure (nCPAP) therapy for obstructive sleep apnoea (OSA), but the role of prophylactic use of HH during the initiation of nCPAP treatment has not been studied so far. Objectives: The aim of the present study was to investigate whether prophylactic HH during the initiation of CPAP would result in improved initial patient comfort and acceptance. Methods: In 44 consecutive, previously untreated OSA patients with no history of upper airway dryness, CPAP titration with and without HH was performed on two consecutive nights in a randomised order. The patients were interviewed after each treatment night in order to establish the comfort of the treatment, and, after the second treatment, they were asked which of the two nights they considered more pleasant, and which treatment they would prefer for long-term use. Results: Following CPAP titration with HH, 32 patients (73%) claimed to have had a better night’s sleep than usual (i.e. without CPAP treatment) compared with 33 patients (75%) saying the same following CPAP treatment without HH. For 21 patients (47.7%) treatment with HH was more pleasant, 23 (52.3%) saw no difference or said that treatment without HH was more pleasant. Nineteen patients (43.2%) gave preference to treatment with HH for long-term use, while 25 patients (56.8%) had no preference or said they would prefer treatment without HH. Conclusions: The use of HH during the initiation phase of CPAP treatment was associated neither with an initial improvement in comfort nor with greater initial treatment acceptance.

Plasma leptin levels and cardiac sympathetic function in patients with obstructive sleep apnoea-hypopnoea syndrome

Background: The control of body weight and cardiac sympathetic function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of...

Heated Humidification during Nasal Continuous Positive Airway Pressure for Obstructive Sleep Apnea Syndrome: Objective Evaluation of Efficacy with Nasal Peak Inspiratory Flow Measurements

Nasal obstruction is one of the most frequent and sometimes troublesome side effects of nasal continuous positive airway pressure (nCPAP) therapy for obstructive sleep apnea syndrome (OSAS). We describe a 60-year-old man with allergic seasonal rhinitis and OSAS, with worsening nasal symptoms 1 week after beginning home nCPAP, making nCPAP use difficult (nasal peak inspiratory flow [nPIF], 80 L/minute [57% of his best]). No significant improvement was obtained with topical steroids or cold humidification. Heated humidification was then considered, achieving an improvement in mean nPIF and symptom scores. An acceptable compliance with CPAP could be obtained during the heated humidification period (3.9 hours of mean daily use). In this patient with moderately severe OSAS and allergic rhinitis, monitoring nasal symptoms and nasal PIF objectively showed the benefit of heated humidification to overcome nasal intolerance and increase compliance to nCPAP treatment.