Vitamin D deficiency in patients evaluated for obstructive sleep apnea: is it associated with disease severity?

PURPOSE: The aim of the present study was to assess vitamin D levels in a large cohort of OSA patients and to investigate possible correlations with clinical and polysomnographic parameters. METHODS: In this cross-sectional study, 685 consecutive patients underwent type 1 polysomnography (PSG) for OSA diagnosis. They were grouped according to apnea-hypopnea index (AHI) as mild, moderate, and severe. Patients with AHI < 5 served as controls. Demographic, PSG data, and serum levels of vitamin D were measured and compared between groups. RESULTS: OSA was diagnosed in 617 of the patients (90%). Of those, 94 (15%) had mild OSA, 150 (24%) moderate OSA, and 373 (61%) severe OSA. The risk of vitamin D deficiency (< 20 ng/mL) was observed in 38% of the cohort. OSA patients had lower vitamin D levels compared to controls (23 ng/mL vs 26 ng/mL, p = 0.006). The lowest levels of vitamin D [mean 21] (p < 0.001 among all groups) and the higher prevalence for vitamin D deficiency (45%) were observed in severe OSA patients. After multiparametric adjustments for age, gender, obesity, and comorbidities, severe OSA showed significant independent associations with the risk of vitamin D deficiency [OR (95% CI) 2.002 (1.049-3.819), p = 0.035]. CONCLUSIONS: A large proportion of patients referred for OSA evaluation had vitamin D deficiency, which was independently associated with severe OSA. However, further research is needed in order to determine the role of vitamin D in OSA patients.

Complex sleep apnea after full-night and split-night polysomnography: the Greek experience.

PURPOSE: Treatment-emergent central sleep apnea (TE-CSA) is defined as the emergence or persistence of central respiratory events during the initiation of positive airway pressure (PAP) without a back-up rate in obstructive sleep apnea (OSA) patients and after significant resolution of obstructive events. Previous studies have estimated a prevalence from 0.56 to 20.3%. The aim of this study was to establish the prevalence of TE-CSA in a Greek adult population. METHODS: One thousand fifty nine patients with newly diagnosed OSA, who were referred to the Sleep Disorders Center of Evangelismos Hospital of Athens over an 18-month period, were included in this study. A split-night polysomnography (PSG), or two formal overnight PSGs (diagnostic and continuous PAP (CPAP) titration study), were performed. RESULTS: Patients with OSA were divided in two groups; the first group included 277 patients, who underwent two separate studies (diagnostic and CPAP titration study), and the second group 782 patients, who underwent split-night studies. The prevalence of TE-CSA in the first group was 2.53% (7 patients), and in the second group was 5.63% (44 patients). CONCLUSIONS: The prevalence of TE-CSA in Greece was lower compared to most previous reported studies. The significant variation in the prevalence of TE-CSA between different centers throughout the world is mainly associated with the used diagnostic criteria as well as methodological and technical aspects.

Evaluation of Inflammatory Markers in a Large Sample of Obstructive Sleep Apnea Patients without Comorbidities.

Systemic inflammation is important in obstructive sleep apnea (OSA) pathophysiology and its comorbidity. We aimed to assess the levels of inflammatory biomarkers in a large sample of OSA patients and to investigate any correlation between these biomarkers with clinical and polysomnographic (PSG) parameters. This was a cross-sectional study in which 2983 patients who had undergone a polysomnography for OSA diagnosis were recruited. Patients with known comorbidities were excluded. Included patients (n = 1053) were grouped according to apnea-hypopnea index (AHI) as mild, moderate, and severe. Patients with AHI < 5 served as controls. Demographics, PSG data, and levels of high-sensitivity C-reactive protein (hs-CRP), fibrinogen, erythrocyte sedimentation rate (ESR), and uric acid (UA) were measured and compared between groups. A significant difference was found between groups in hs-CRP, fibrinogen, and UA. All biomarkers were independently associated with OSA severity and gender (p < 0.05). Females had increased levels of hs-CRP, fibrinogen, and ESR (p < 0.001) compared to men. In contrast, UA levels were higher in men (p < 0.001). Our results suggest that inflammatory markers significantly increase in patients with OSA without known comorbidities and correlate with OSA severity. These findings may have important implications regarding OSA diagnosis, monitoring, treatment, and prognosis. This trial is registered with ClinicalTrials.gov number NCT03070769.

Tiotropium Respimat Soft Mist Inhaler versus HandiHaler to improve sleeping oxygen saturation and sleep quality in COPD.

PURPOSE: Patients with chronic obstructive pulmonary disease (COPD) have poor sleep quality as a result of various alterations in oxygenation parameters and sleep macro- and micro-architecture. There is a shortage of data to support the efficacy of long-acting inhaled anticholinergic agents in improving these adverse effects, which are known to have a negative impact on clinical outcomes. We aimed to compare the tiotropium Respimat Soft Mist Inhaler and the HandiHaler in terms of their effects on sleeping oxygen saturation (SaO2) and sleep quality in patients with COPD. METHODS: In a randomized, open-label, parallel-group trial involving 200 patients with mild to moderate COPD (resting arterial oxygen tension >60 mmHg while awake), we compared the effects of 6 months' treatment with the two devices on sleeping SaO2 and sleep quality. Overnight polysomnography and pulmonary function testing were performed at baseline and after 6 months' treatment. RESULTS: A total of 188 patients completed the trial. Both groups showed significant improvement in minimum sleep SaO2 and time of sleep spent with SaO2 below 90 (TST90) compared to baseline. The patients using the Respimat had significantly better TST90 than did those using the HandiHaler. Sleep disturbance was highly variable in these patients, but the sleep stage durations were significantly better in the Respimat group. CONCLUSIONS: Sleeping SaO2 can be improved by tiotropium delivered using either the HandiHaler device or the Respimat Soft Mist Inhaler. However, the patients who used the Respimat device had significantly better TST90 and sleep architecture parameters.

Multum non multa: airway distensibility by forced oscillations.

Airway distensibility although appears to be unaffected by airway smooth muscle tone probably related to airway remodelling, after bronchodilator treatment is significantly increased in subjects with asthma. We assessed airway distensibity and its first moment derivative in two patients with mild intermittent asthma and normal spirometry. The increase in airway distensibility after bronchodilation measured at the tidal volume range during quiet breathing by forced oscillations was not accompanied by a change in its first moment, while the latter showed a significant increase in a second patient after anti-inflammatory treatment. It appears that airway distensibility is sensitive to reduction of bronchial smooth muscle tone after bronchodilation, but in addition its first moment might provide information on a change of both bronchial smooth muscle tone and small airways inflammation.

Obstructive sleep apnea should be treated in patients with idiopathic pulmonary fibrosis.

STUDY OBJECTIVES: The most recent idiopathic pulmonary fibrosis (IPF) guidelines include obstructive sleep apnea (OSA) among the IPF-associated comorbidities. Furthermore, they recognize the paucity of studies related to continuous positive airway pressure(CPAP) treatment in this patient group and call for intensive research in this field. Our aim was to assess the effect of CPAP treatment on sleep and overall life quality parameters, morbidity, and mortality in IPF patients with OSA. METHODS: Ninety-two treatment-naive, newly diagnosed, consecutive IPF patients underwent overnight-attended polysomnography (PSG). In those patients with an apnea-hypopnea index (AHI) of ≥15, therapy with CPAP was initiated. Patients were divided into poor and good CPAP compliance groups. All subjects completed multiple quality-of-life and sleep instruments before CPAP initiation and at 1 year after the start of CPAP treatment. RESULTS: The good CPAP compliance group (37 patients) showed statistically significant improvement in all quality-of-life and sleep instruments after 1 year's CPAP treatment. The poor CPAP compliance group (18 patients) showed significant changes of smaller strength only in a minority of the used instruments. During the 24-month follow-up period after CPAP initiation, three patients from the CPAP poor compliance group died, whereas all patients from the good CPAP compliance group remained alive. CONCLUSION: Early OSA recognition and treatment is crucial in a fatal disease such as IPF. Effective CPAP treatment in IPF patients with OSA results in a significant improvement in daily living activities and quality of sleep and life. Good CPAP compliance appears to improve mortality.

Intensive versus standard follow-up to improve continuous positive airway pressure compliance.

We aimed to compare the effect of intensive versus standard interventions on continuous positive airway pressure (CPAP) adherence 2 years after CPAP initiation, as well as on sleepiness, quality of life, depression, hospitalisation and death rate due to cardiovascular disease (CVD). 3100 patients with newly diagnosed sleep apnoea were randomised into the standard group, with usual follow-up care, or the intensive group, with additional visits, telephone calls and education. Subjective daytime sleepiness (Epworth Sleepiness Scale; ESS), quality of life (36-item Short Form Health Survey; SF-36) and the patient's level of depression (Beck Depression Inventory; BDI) were recorded before and 2 years after CPAP initiation, together with CVD hospitalisations and death rate. 2 years after CPAP initiation, the intensive group used CPAP significantly more than the standard group (6.9 versus 5.2 h per night; p<0.001). ESS, SF-36 and BDI scores were also significantly better in the intensive group. Furthermore, the standard group had significantly more deaths and hospitalisations due to CVD. CPAP usage can be improved by both intensive and standard patient support. However, the patients who received intensive CPAP support had significantly better ESS, BDI and SF-36 scores, and lower cardiovascular morbidity and mortality, suggesting that an intensive programme could be worthwhile.

Abnormal cytokine profile in patients with obstructive sleep apnea-hypopnea syndrome and erectile dysfunction.

Patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) show a high prevalence of erectile dysfunction (ED). Although the underlying pathogenesis is still unknown, endothelial dysfunction, induced by inflammatory cytokines, chemokines, and adhesion molecules, has been proposed as a possible mechanism. The aim of this study was to assess whether OSAHS is associated with activation of the inflammatory cytokine system in patients with ED compared to the matched OSAHS patients with normal sexual function. Thirty-one patients with severe OSAHS and ED were included. Fifteen patients with severe OSAHS and without ED served as controls. Serum concentrations of high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor-α (TNF-a), interleukin-6 (IL-6), interleukin-8 (IL-8), and adiponectin were measured after the diagnostic polysomnography. We found that hsCRP levels were significantly elevated in OSAHS patients with ED compared to controls. Similarly, TNF-a levels, IL-6, and IL-8 were elevated in OSAHS patients with ED compared to controls. Serum adiponectin levels were lower in OSAHS-ED patients, but the difference did not reach statistical significance. The presence of ED in patients with severe OSAHS is associated with elevated levels of inflammatory markers, underlining a possible involvement of endothelial dysfunction in the pathogenesis of ED.

Medical treatment with thiamine, coenzyme Q, vitamins E and C, and carnitine improved obstructive sleep apnea in an adult case of Leigh disease.

PURPOSE: The multi-organ involvement of mitochondrial diseases means that patients are likely to be more vulnerable to sleep disturbances. We aimed to assess if early recognition and treatment of obstructive sleep apnea (OSA) in patients with Leigh disease may influence primary disease outcome. METHODS: We describe a case of adult-onset Leigh disease presenting as severe brainstem encephalopathy of subacute onset. Based on the clinical symptoms that developed after the appearance of the neurological disease, an attended overnight polysomnography examination was performed. RESULTS: A marked clinical recovery was seen after administration of high doses of thiamine, coenzyme Q, L-carnitine, and vitamins C and E, combined with effective treatment with continuous positive airway pressure for the underlying severe obstructive sleep apnea (OSA). The latter condition was diagnosed on the basis of suggestive symptoms that appeared a few weeks before the establishment of the neurological disease. The improvement in the neurological disease (based on clinical and brain MRI features) with the appropriate medical treatment also resulted in a significant improvement in the OSA. CONCLUSIONS: Early recognition and treatment of sleep apnea may not only improve sleep and overall quality of life but also ameliorate the deleterious effects of nocturnal desaturations on the neurological features. This may be crucial for disease outcome when added to the generally advised pharmacological therapy.

CPAP therapy in patients with idiopathic pulmonary fibrosis and obstructive sleep apnea: does it offer a better quality of life and sleep?

BACKGROUND: The recent literature shows an increased incidence of obstructive sleep apnea (OSA) in patients with idiopathic pulmonary fibrosis (IPF). On the other hand, there are no published studies related to continuous positive airway pressure (CPAP) treatment in this patient group. Our aim was to assess the effect of CPAP on sleep and overall life quality parameters in IPF patients with OSA and to recognize and overcome possible difficulties in CPAP initiation and acceptance by these patients. METHODS: Twelve patients (ten males and two females, age 67.1 ± 7.2 years) with newly diagnosed IPF and moderate to severe OSA, confirmed by overnight attended polysomnography, were included. Therapy with CPAP was initiated after a formal in-lab CPAP titration study. The patients completed the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index (PSQI), the Functional Outcomes in Sleep Questionnaire (FOSQ), the Fatigue Severity Scale (FSS), the SF-36 quality of life questionnaire, and the Beck Depression Inventory (BDI) at CPAP initiation and after 1, 3, and 6 months of effective CPAP therapy. RESULTS: A statistically significant improvement was observed in the FOSQ at 1, 3, and 6 months after CPAP initiation (baseline 12.9 ± 2.9 vs. 14.7 ± 2.6 vs. 15.8 ± 2.1 vs. 16.9 ± 1.9, respectively, p = 0.02). Improvement, although not statistically significant, was noted in ESS score (9.2 ± 5.6 vs. 7.6 ± 4.9 vs. 7.5 ± 5.3 vs. 7.7 ± 5.2, p = 0.84), PSQI (10.7 ± 4.4 vs. 10.1 ± 4.3 vs. 9.4 ± 4.7 vs. 8.6 ± 5.2, p = 0.66), FSS (39.5 ± 10.2 vs. 34.8 ± 8.5 vs. 33.6 ± 10.7 vs. 33.4 ± 10.9, p = 0.44), SF-36 (63.2 ± 13.9 vs. 68.9 ± 13.5 vs. 72.1 ± 12.9 vs. 74.4 ± 11.3, p = 0.27), and BDI (12.9 ± 5.5 vs. 10.7 ± 4.3 vs. 9.4 ± 4.8 vs. 9.6 ± 4.5, p = 0.40). Two patients had difficulty complying with CPAP for a variety of reasons (nocturnal cough, claustrophobia, insomnia) and stopped CPAP use after the first month, despite intense follow-up by the CPAP clinic staff. Heated humidification was added for all patients in order to improve the common complaint of disabling nocturnal cough. CONCLUSION: Effective CPAP treatment in IPF patients with OSA results in a significant improvement in daily living activities based on the FOSQ, namely an OSA-specific follow-up instrument. Improvement was also noted in other questionnaires assessing quality of life, though not to a statistically significant degree, probably because of the multifactorial influences of IPF on physical and mental health. The probability of poor CPAP compliance was high and could only be eliminated with intense follow-up by the CPAP clinic staff.

Translation and validation of Berlin questionnaire in primary health care in Greece.

BACKGROUND: The aim of our study was to validate a Greek translation of the Berlin Questionnaire (BQ) for obstructive sleep apnoea syndrome (OSAS) and to explore whether this screening questionnaire could be used to help identify primary care patients at greater risk of having OSAS. METHODS: We recruited 189 patients visiting a primary health care setting on the island of Crete, Greece. They all completed the Greek Version of the BQ. Patients were then referred to a Sleep Disorders Unit for evaluation of suspected sleep-disordered breathing. RESULTS: A PSG study was performed in 129 of the 189 subjects (68.3%). BQ identified 74.4% (n = 96) of the patients as high-risk for OSAS and the remaining 25.6% (n = 33) as low-risk. The sensitivity and specificity of BQ for OSAS diagnosis were 76% and 40%, respectively, for an apnoea-hypopnoea index (AHI) ≥5 per hour but <15 per hour, 84% and 61% for an AHI ≥15 per hour but ≤30 per hour, and 79% and 39% for an AHI >30 per hour. CONCLUSIONS: In conclusion, the Greek Version of the BQ is a useful instrument for identifying patients at risk for OSAS in primary health care in Greece. The findings of our study confirm that such screening tools should be used by primary care clinicians for OSAS prediction.

CRP evolution pattern in CPAP-treated obstructive sleep apnea patients. Does gender play a role?

BACKGROUND-AIM: C-reactive protein (CRP) is directly implicated in atherogenesis and associated cardiovascular morbidity in patients with obstructive sleep apnea (OSA). Effective continuous positive airway pressure (CPAP) treatment has been shown to gradually decrease CRP levels and thus consequently improve disease-related cardiovascular morbidity. However, the influence of gender on the CRP evolution pattern has never been assessed before. The aim of our study was to investigate possible gender differences in CRP evolution in OSA patients 3 and 6 months after the start of effective CPAP treatment. METHODS: The study population consisted of 436 patients (252 males/184 females) with newly diagnosed moderate to severe OSA and good CPAP compliance assessed by a thorough follow up. High-sensitivity C-reactive protein (hs-CRP) was assessed before CPAP initiation and at the third and sixth month of the follow-up period. RESULTS: C-reactive protein values showed a statistically significant decrease at the third and sixth month of CPAP therapy [initial values 0.79 ± 0.65 mg/dL versus 0.70 ± 0.52 mg/dL (p < 0.05) after 3 months and 0.30 ± 0.33 mg/dL (p < 0.001) after 6 months of CPAP therapy]. When patients were divided into males and females, the above evolution pattern was changed. At the third month time point, the CRP values showed a statistically significant decrease only in males (from 0.74 ± 0.53 mg/dL to 0.61 ± 0.5 mg/dL, p < 0.01) while females showed only minimal and insignificant changes (from 0.87 ± 0.79 mg/dL to 0.83 ± 0.51 mg/dL, p > 0.05). After 6 months' treatment, CRP decreased significantly in both genders (males from 0.74 ± 0.53 mg/dL to 0.28 ± 0.32 mg/dL, p < 0.001 and females from 0.87 ± 0.79 mg/dL to 0.34 ± 0.36 mg/dL, p < 0.001). CONCLUSION: Our results suggest a delay in the normalization of CRP levels in females despite effective CPAP treatment. A time period of at least 6 months appeared to be required in women in order to reduce CRP levels and consequent cardiovascular risk. In contrast, CPAP's protective role in males is achieved at an earlier time point. Gender-related hormonal and genetic factors may influence the above CRP evolution pattern.

Utility of formulas predicting the optimal nasal continuous positive airway pressure in a Greek population.

BACKGROUND: There have been reports that optimal CPAP pressure can be predicted from a previously derived formula, with the Hoffstein formula being the most accurate and accepted in the literature so far. However, the validation of this predictive model has not been applied in different clinical settings. Our aim was to compare both the Hoffstein prediction formula and a newly derived formula to the CPAP pressure setting assessed during a formal CPAP titration study. METHODS: We prospectively studied 1,111 patients (871 males/240 females) with obstructive sleep apnea hypopnea syndrome (OSAHS) undergoing a CPAP titration procedure. In this large population sample, we tested the Hoffstein formula, utilizing body mass index (BMI), neck circumference and apnea/hypopnea index (AHI), and we compared it with our new formula that included not only AHI and BMI but also smoking history and gender adjustment. RESULTS: We found that using the Hoffstein prediction formula, successful prediction (predicted CPAP pressure within ±2 cm H(2)O compared to the finally assessed optimum CPAP pressure during titration) was accomplished in 873 patients (79%), with significant correlation between CPAP predicted pressure (CPAPpred(1)) and the optimum CPAP pressure (CPAPopt) [r = 0.364, p < 0.001]. With the new formula, including smoking history and gender adjustment, successful prediction was accomplished in 1,057 patients (95%), with significant correlation between CPAP predicted pressure (CPAPpred(2)) and the CPAPopt (r = 0.392, p < 0.001). However, there was a highly significant correlation between the two formulas (r = 0.918, p < 0.001). CONCLUSIONS: We conclude that the level of CPAP necessary to abolish sleep apnea can be successfully predicted from both equations, using common clinical measurements and prediction formulas that may be useful in calculating the starting pressure for initiating CPAP titration. It may also be possible to shorten CPAP titration and perhaps in selected cases to combine it with the initial diagnostic study.

Prediction of obstructive sleep apnea syndrome in a large Greek population.

PURPOSE: We aimed to evaluate the predictive value of anthropometric measurements and self-reported symptoms of obstructive sleep apnea syndrome (OSAS) in a large number of not yet diagnosed or treated patients. Commonly used clinical indices were used to derive a prediction formula that could identify patients at low and high risk for OSAS. METHODS: Two thousand six hundred ninety patients with suspected OSAS were enrolled. We obtained weight; height; neck, waist, and hip circumference; and a measure of subjective sleepiness (Epworth sleepiness scale--ESS) prior to diagnostic polysomnography. Excessive daytime sleepiness severity (EDS) was coded as follows: 0 for ESS ≤ 3 (normal), 1 for ESS score 4-9 (normal to mild sleepiness), 2 for score 10-16 (moderate to severe sleepiness), and 3 for score >16 (severe sleepiness). Multivariate linear and logistic regression analysis was used to identify independent predictors of apnea-hypopnea index (AHI) and derive a prediction formula. RESULTS: Neck circumference (NC) in centimeters, body mass index (BMI) in kilograms per square meter, sleepiness as a code indicating EDS severity, and gender as a constant were significant predictors for AHI. The derived formula was: AHIpred = NC × 0.84 + EDS × 7.78 + BMI × 0.91 - [8.2 × gender constant (1 or 2) + 37]. The probability that this equation predicts AHI greater than 15 correctly was 78%. CONCLUSIONS: Gender, BMI, NC, and sleepiness were significant clinical predictors of OSAS in Greek subjects. Such a prediction formula can play a role in prioritizing patients for PSG evaluation, diagnosis, and initiation of treatment.

Patients with idiopathic pulmonary fibrosis with and without obstructive sleep apnea: differences in clinical characteristics, clinical outcomes, and the effect of PAP treatment.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) in patients with idiopathic pulmonary fibrosis (IPF) is associated with worse mortality and clinical outcome. We aimed to assess differences between patients with IPF with and without OSA and the effect of positive airway pressure treatment on sleep and overall life quality, morbidity, and mortality in these patients. METHODS: Forty-five patients with newly diagnosed IPF underwent polysomnography. Using an apnea-hypopnea index ≥ 15 events/h for OSA diagnosis resulted in 16 patients with IPF and 29 with IPF-OSA. The patients completed the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Functional Outcomes in Sleep Questionnaire, Fatigue Severity Scale, Short Form-36 life questionnaire, and Beck Depression Inventory before and at the end of the follow-up period. RESULTS: Patients with IPF-OSA showed the most severe functional impairments in questionnaires, especially for General Health component of the Short Form-36 life questionnaire (37 vs 58, P = .03). At the 7-year follow-up, 16 (36%) patients had died, 6 (38%) in the IPF group and 10 (35%) in IPF-OSA group. Patients with ≥6-hour positive airway pressure use had better survival compared with patients with <6-hour use (P = .04). Significant improvement was also observed in Epworth Sleepiness Scale (3 vs 6, P = .03), Pittsburgh Sleep Quality Index (5 vs 8, P = .01), and Fatigue Severity Scale (37 vs 48, P = .008) score in patients with ≥4-hour positive airway pressure use. CONCLUSIONS: OSA plays a significant role on clinical features and quality of life in patients with IPF. Effective positive airway pressure treatment results in a significant improvement in sleepiness, fatigue, sleep quality, and mortality. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: CPAP Therapy in Patients With Idiopathic Pulmonary Fibrosis and Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/record/NCT01637831; Identifier: NCT01637831.

C-reactive protein evolution in obstructive sleep apnoea patients under CPAP therapy.

BACKGROUND: C-reactive protein (CRP) is recognized as a potential factor implicated in atherogenesis and associated cardiovascular morbidity. The aim of our study was to assess the CRP evolution during 1-year follow-up period in obstructive sleep apnoea (OSA) patients under CPAP treatment. METHODS: Five hundred and twenty-eight patients with newly diagnosed moderate to severe OSA were included. CRP was assessed before CPAP initiation and at the 3rd, 6th and 12th month of the follow-up period. Patients were divided into good and poor CPAP compliance groups. RESULTS: A significant reduction in CRP levels was observed after CPAP therapy (0·74±0·62mgdL(-1) vs. 0·31±0·29mgdL(-1) , P<0·001) in the whole patient group. The evolution of CRP values showed a gradual decrease at 3months with a steep decline at 6months, reaching a plateau after this time point. When the patients were divided into those with good and poor compliance with CPAP therapy, the above CRP evolution pattern was observed only in the former group. CONCLUSION: Good CPAP compliance results in a significant CRP reduction. To achieve the best positive impact on cardiovascular morbidity and mortality, a time period of at least 6months of CPAP use is required.