Is COPD the Determinant Factor for Myocardial Injury and Cardiac Wall Stress in OSA Patients?

Background and Objectives: Evidence shows that COPD-OSA overlap syndrome (OS) is more frequently accompanied by cardiovascular disease (CVD) in comparison to either disease alone. The aim of the study was to explore whether patients with OS have a higher burden of subclinical myocardial injury and wall stress compared with OSA patients. Materials and Methods: Consecutive patients, without established CVD, underwent polysomnography and pulmonary function testing, due to suspected sleep-disordered breathing. An equal number of patients with OS (n = 53, with an apnea hypopnea index (AHI) > 5/h and FEV1/FVC < 0.7) and patients with OSA (n = 53, AHI > 5/h and FEV1/FVC > 0.7) were included in the study. The detection of asymptomatic myocardial injury and wall stress was performed via the assessment of serum high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), respectively. Results: OS patients were older (p < 0.001) and had worse hypoxemic parameters, namely average oxyhemoglobin saturation (SpO2) (p = 0.002) and time spent with SpO2 < 90% (p = 0.003) during sleep as well as daytime pO2 (p < 0.001), than patients with OSA. No difference was observed between groups in terms of Epworth Sleepiness Scale (p = 0.432) and AHI (p = 0.587). Both levels of hs-cTnT (14.2 (9.1-20.2) vs. 6.5 (5.6-8.7) pg/mL, p < 0.001) and NT-proBNP (93.1 (37.9-182.5) vs. 19.2 (8.3-35.4) pg/mL, p < 0.001) were increased in OS compared to OSA patients. Upon multivariate linear regression analysis, levels of NT-proBNP and hs-cTnT correlated with age and average SpO2 during sleep. Conclusions: Our study demonstrated higher levels of hs-cTnT and NT-proBNP in OS patients, indicating an increased probability of subclinical myocardial injury and wall stress, compared with OSA individuals.

Effect of the Implementation of a Structured Diet Management Plan on the Severity of Obstructive Sleep Apnea: A Systematic Review

PURPOSE OF REVIEW

The prevalence of obstructive sleep apnea (OSA) is increasing worldwide, in line with the increase in obesity prevalence. Taken into consideration the low compliance rates to continuous positive airway pressure (CPAP) treatment, and since obesity is a risk factor for OSA, these patients should receive additional counseling for weight loss through a diet plan. The aim of this review is to examine the role of a structured diet management plan on OSA severity, nocturnal oxygen indices, and subjective sleep parameters.

RECENT FINDINGS

Τhis systematic review of the literature resulted in four studies and demonstrated that severity of OSA, assessed by the apnea-hypopnea index, is reduced by a dietary management plan when delivered through an educational program. Moreover, nocturnal oxygenation is improved, as well as subjective sleep parameters, when initiating a diet on top of CPAP use. In summary, the present systematic review reports on the beneficial effects of a structured diet management plan in patients with OSA. Although CPAP remains the gold standard of OSA treatment, a specific dietary plan should be sought when managing patients with OSA. Nevertheless, still the evidence is low, and further research on this field is needed to reduce the burden of OSA.

Effect of compliance to continuous positive airway pressure on exacerbations, lung function and symptoms in patients with chronic obstructive pulmonary disease and obstructive sleep apnea (overlap syndrome)

INTRODUCTION

Patients with overlap syndrome (OS), that is obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD), are at increased risk of acute exacerbations related to COPD (AECOPD). We assessed the effect of CPAP compliance on AECOPD, symptoms and pulmonary function in OS patients.

METHODS

Consecutive OS patients underwent assessment at baseline and at 12 months under treatment with CPAP of: AECOPD and hospitalizations, COPD Assessment Test (CAT) and modified British Medical Research Council (mMRC) questionnaires, pulmonary function testing and 6-min walking test (6MWT).

RESULTS

In total, 59 patients (54 males) with OS were followed for 12 months and divided post hoc according to CPAP compliance into: group A with good (≥4 h CPAP use/night, n = 29) and group B with poor (<4 h CPAP use/night, n = 30) CPAP compliance. At 12 months, group A showed improvements in FEV₁ (p = 0.024), total lung capacity (p = 0.024), RV/TLC (p = 0.003), 6MWT (p < 0.001) and CAT (p < 0.001). COPD exacerbations decreased in patients with good CPAP compliance from baseline to 12 months (17 before vs. 5 after, p = 0.001), but not in those with poor compliance (15 before vs. 15 after, p = 1). At multivariate regression analysis, COPD exacerbations were associated with poor CPAP compliance (β = 0.362, 95% CI: 0.075-0.649, p = 0.015).

CONCLUSIONS

When compared to poorly compliant patients, OS patients with good CPAP compliance had a lower number of AECOPD and showed improved lung function and COPD related symptoms.

Vitamin D Levels in Patients with Overlap Syndrome, Is It Associated with Disease Severity?

Background: The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) has been defined as overlap syndrome (OVS). Recently, a link between OSA, COPD and Vitamin D (Vit D) serum concentration was reported, however, evidence regarding Vit D status in patients with OVS is scarce. The aim of the present study was to evaluate Vit D serum levels and to explore the association of those levels with anthropometric, pulmonary function and sleep parameters in patients with OVS. Methods: Vit D serum levels were measured in patients diagnosed with OVS, as confirmed by overnight polysomnography and pulmonary function testing. Results: A total of 90 patients (79 males and 11 females) were included in the analysis. The patients were divided into three groups matched for age, gender, and BMI: the control group that included 30 patients (27 males and 3 females), the OSA group that included 30 patients (26 males and 4 females), and the OVS group that included 30 patients (26 males and 4 females). Patients with OVS exhibited decreased serum 25(OH)D levels compared with OSA patients and controls (14.5 vs. 18.6 vs. 21.6 ng/mL, p < 0.001). In the OVS group, multiple linear regression analysis identified AHI and FEV1, as predictors of serum 25(OH)D levels (p = 0.041 and p = 0.038, respectively). Conclusions: Lower Vit D levels have been observed in patients with OVS compared with OSA patients and non-apneic controls, indicating an increased risk of hypovitaminosis D in this population which might be associated with disease severity.

Changes in Exercise Capacity of Patients With Obstructive Sleep Apnea Following Treatment With Continuous Positive Airway Pressure

Introduction: Patients with obstructive sleep apnea (OSA) frequently complain of fatigue during exercise. Treatment with continuous positive airway pressure (CPAP) ameliorates OSA-related symptoms and may reduce the burden of OSA on coexistent diseases. However, the role of CPAP on exercise capacity in OSA has not been fully investigated.

Aim: The aim of this study is to assess exercise capacity in a group of newly diagnosed OSA patients, without known comorbidities, following treatment with CPAP.

Methods: Consecutively diagnosed OSA patients by polysomnography completed the International Physical Activity Questionnaire (IPAQ) and underwent cardiopulmonary exercise testing (CPET) and pulmonary function testing at baseline of OSA diagnosis three months after adherence to CPAP treatment.

Results: A total of 40 OSA patients (Apnea-Hypopnea Index (ΑΗΙ)>15 events/hour) of whom 29 (72.5%) males with an average age of 42±2.5 years were enrolled in the study. OSA patients had a mean peak oxygen uptake (V̇O₂) value of 40.3 ±8.4 ml/kg/min (77.7±15%), which was improved after three months on CPAP treatment, 47.6±7.9 ml/kg/min (92.9±10.5%). (p=0.002). In addition, patients’ mean work (W) value increased significantly from baseline to three months of treatment with CPAP (101.5±30 watts vs 78.6±18.5 watts. p=0.015, respectively). There were no significant differences in terms of physical activity, as noted in IPAQ, before and after OSA therapy (p=0.075).

Conclusions: In the present study, OSA is associated with impaired exercise capacity, which seems to be improved after short-term treatment with PAP. Further evidence is warranted to elucidate whether CPET could be routinely used to monitor treatment responses of OSA with CPAP.

Feasibility and safety of treatment switch from Pirfenidone to Nintedanib in patients with idiopathic pulmonary fibrosis: a real-world observational study

OBJECTIVE

Idiopathic Pulmonary Fibrosis is a disease characterized by a devastating fibrosing process. Two anti-fibrotic agents, pirfenidone and nintedanib, have been found to alter the disease progression. In this study, we sought to determine whether switching treatment to nintedanib is feasible and safe in patients that had to discontinue treatment with pirfenidone due to side effects.

PATIENTS AND METHODS

We analyzed patients that had to discontinue pirfenidone due to side effects. Patients were prospectively enrolled for treatment with nintedanib between March 2015 and June 2019. Side effects and Pulmonary Function Tests were recorded.

RESULTS

12 patients received nintedanib after discontinuing treatment with pirfenidone. Side-effects that led to discontinuation were diarrhea (33.3%), nausea (16.6%), photosensitivity (33.3%) and difficulty adhering to pirfenidone's dosage scheme (16.6%). After the initiation of nintedanib, diarrhea was the most common side effect (66.6%). Four patients of these patients could not tolerate the full dose of 300 mg daily and had to reduce it to 200 mg daily. No patient has had experienced liver damage. During the last twelve months of treatment with pirfenidone, mean ΔFCV was +2.47 ± 3.69%, mean ΔDLco was -0.36 ± 2.64% and mean difference of the distance walked during the 6MWT was 5 ± 56.48 meters. During the first year of treatment with nintedanib, mean ΔFCV was -1.32 ± 1.12% (p=0.68), mean ΔDLco was -1.59 ± 3.45% (p=0.54) and mean difference of the distance walked during the 6MWT was 14.17 ± 59 meters (p=0.078). 50% of patients had stable disease under pirfenidone (6-month FVC decline < 5% and/or 6-month DLco decline < 10%) vs. 50% under nintedanib, 33.3% had marginal 6-month decline (5% ≤ 6-month FVC ≤ 10% and/or (≤ 10% 6- month DLco decline ≤15%) under pirfenidone vs. 33.3% under nintedanib and 16.6% had disease progression (6-month FVC decline > 10% and/or 6-month DLco decline > 15%) under pirfenidone vs. 16.6% under nintedanib.

CONCLUSIONS

These results suggest that nintedanib is a safe option for the treatment of patients that had to discontinue pirfenidone due to adverse reactions. Further studies with greater patient numbers are needed for accurate results concerning efficacy.

Burden of Comorbidities in Patients with OSAS and COPD-OSAS Overlap Syndrome

Background and Objectives: Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are usually associated with multi-morbidity. The aim of this study was to retrospectively investigate the prevalence of comorbidities in a cohort of patients with OSAS and COPD-OSAS overlap syndrome (OS) patients and to explore differences between these two groups. Materials and Methods: Included were consecutive OS patients and OSAS patients who had been referred to our sleep laboratory, and were matched in terms of sex, age, BMI, and smoking history. Presence of comorbidities was recorded based on their medical history and after clinical and laboratory examination. Results: The two groups, OS patients (n = 163, AHI > 5/h and FEV₁/FVC < 0.7) and OSAS patients (n = 163, AHI > 5/h, and FEV₁/FVC > 0.7), did not differ in terms of apnea hypopnea index (p = 0.346), and oxygen desaturation index (p = 0.668). Compared to OSAS patients, OS patients had lower average SpO₂ (p = 0.008) and higher sleep time with oxygen saturation <90% (p = 0.002) during sleep, and lower PaO₂ (p < 0.001) and higher PaCO₂ (p = 0.04) in wakefulness. Arterial hypertension was the most prevalent comorbidity for both OS and OSAS, followed by dyslipidemia, cardiovascular disease (CVD) and diabetes. OS was characterized by a higher prevalence of total comorbidities (median (IQR):2 (1–3) vs. 2 (1–2), p = 0.033), which was due to the higher prevalence of CVD (p = 0.016) than OSAS. No differences were observed in other comorbidities. Conclusions: In OS patients, nocturnal hypoxia and impaired gas exchange in wakefulness are more overt, while a higher burden of CVD is observed among them in comparison to sex-, age- and BMI-matched OSAS patients.

Is kidney a new organ target in patients with obstructive sleep apnea? Research priorities in a rapidly evolving field

The bidirectional relationship between sleep disordered breathing and chronic kidney disease (CKD) has recently gained a lot of interest. Several lines of evidence suggest the high prevalence of coexistent obstructive sleep apnea (OSA) in patients with CKD and end-stage renal disease (ESRD). In addition, OSA seems to result in loss of kidney function in some patients, especially in those with cardio-metabolic comorbidities. Treatment of CKD/ESRD and OSA can alter the natural history of each other; still better phenotyping with selection of appropriate treatment approaches is urgently needed. The aim of this narrative review is to provide an update of recent studies on epidemiological associations, pathophysiological interactions, and management of patients with OSA and CKD or ESRD.

Cardiovascular Disease in Patients with Chronic Obstructive Pulmonary Disease, Obstructive Sleep Apnoea Syndrome and Overlap Syndrome

Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnoea syndrome (OSAS) are among the most prevalent chronic respiratory disorders. Accumulating data suggest that there is a significant burden of cardiovascular disease (CVD) in patients with COPD and OSAS, affecting negatively patients' quality of life and survival. Overlap syndrome (OS), i.e. the co-existence of both COPD and OSAS in the same patient, has an additional impact on the cardiovascular system multiplying the risk of morbidity and mortality. The underlying mechanisms for the development of CVD in patients with either OSAS or COPD and OS are not entirely elucidated. Several mechanisms, in addition to smoking and obesity, may be implicated, including systemic inflammation, increased sympathetic activity, oxidative stress and endothelial dysfunction. Early diagnosis and proper management of these patients might reduce cardiovascular risk and improve patients' survival. In this review, we summarize the current knowledge regarding epidemiological aspects, pathophysiological mechanisms and present point-to-point specific associations between COPD, OSAS, OS and components of CVD, namely, pulmonary hypertension, coronary artery disease, peripheral arterial disease and stroke.

Sleep medicine and COVID-19. Has a new era begun?

Since late December 2019, COVID-19, the disease caused by the novel coronavirus, SARS-CoV-2, has spread rapidly around the world, causing unprecedented changes in provided health care services. Patients diagnosed with sleep-disordered breathing (SDB) are subject to a higher risk of worse outcomes from COVID-19, due to the high prevalence of coexistent comorbidities. Additionally, treatment with positive airway treatment devices (PAP) can be challenging because of PAP-induced droplets and aerosol. In this context, sleep medicine practices are entering a new era and need to adapt rapidly to these circumstances, so as to provide the best care for patients with SDB. Novel approaches, such as telemedicine, may play an important role in the management of patients with SDB during the COVID-19 pandemic.

Occupational exposures in constrictive bronchiolitis

Bronchiolitis obliterans is a clinical entity which results from a variety of etiologies and has a detrimental impact on patients' quality of life when it remains undiagnosed and untreated. Due to its non-pathognomic clinical symptoms and signs, physicians often proceed to radiological examination, especially with high resolution chest tomography. Histological examination reveals constrictive bronchiolitis, the pathological definition of bronchiolitis obliterans. Due to an almost normal aspect of the lung parenchyma this condition can be missed. However, its recognition and the identification of a possible exposure are important for removing the patient from the incriminating agent. We present a case of constrictive bronchiolitis in a metal-cutting worker, highlighting the principal findings of this disease.

Metabolic Syndrome in Patients with Coexistent Obstructive Sleep Apnea Syndrome and Chronic Obstructive Pulmonary Disease (Overlap Syndrome)

Background: Evidence suggests that metabolic syndrome (MetS) is highly prevalent in patients with obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD). However, data on the prevalence of MetS in patients having both OSAS and COPD, or overlap syndrome (OS), are scarce. The aim of this study was to evaluate the prevalence and identify predictors of MetS in patients with OS. Methods: MetS was evaluated in consecutive patients who were diagnosed with OS by polysomnography and pulmonary function testing. Results: A total of 163 subjects (138 males and 25 females) were included. MetS was present in 38% of OS patients. Patients were divided into group A (OS without MetS group: 101 patients) and group B (OS with MetS group: 62 patients). Groups were similar in terms of pulmonary function and sleep parameters. In group B, abdominal obesity was the most prevalent component of MetS (100%), followed by hypertension (82.3%), hypertriglyceridemia (72.6%), and hyperglycemia (51.6%). Age (P = 0.009) and body mass index (P = 0.029) were independent predictors of MetS in patients with OS. Conclusions: An increased prevalence of MetS was observed in a group of patients with OS. Early identification and treatment of MetS may play a significant role in prevention of complications related to OS.

Increased risk for cardiovascular disease in patients with obstructive sleep apnoea syndrome-chronic obstructive pulmonary disease (overlap syndrome)

INTRODUCTION

Accumulating evidence suggests that cardiovascular disease (CVD) is highly prevalent among patients with concurrent obstructive sleep apnoea syndrome (OSAS) and chronic obstructive pulmonary disease, otherwise known as overlap syndrome (OS).

OBJECTIVES

The aim of this study was to investigate the 10-year risk for CVD in OS patients compared with OSAS patients and controls.

METHODS

Consecutive patients, referred for symptoms suggestive of OSAS, were evaluated with polysomnography and pulmonary function testing. Cardiovascular risk was assessed using the Framingham risk score (FRS) and systematic coronary risk evaluation (SCORE).

RESULTS

Overall, 244 participants (184 males) without CVD and diabetes were divided into 3 groups: controls (n = 63), OSAS (n = 139) and OS (n = 42). Both FRS and SCORE were found to be elevated in the OS group compared with the OSAS and control groups (P < .001 for all). In multivariate analysis, age (β = .461, P < .001), forced expiratory volume in first second (β = -.285, P = .036) and oxygen desaturation index (ODI) (β = .234, P = .007) were major determinants for the SCORE, whereas age (β = .308, P < .001) and apnoea-hypopnoea index (β = .252, P = .010) for the FRS.

CONCLUSION

In our study, an increased risk for CVD was observed in a group of patients with OS at the time of their initial evaluation. Further studies are needed in the field of OS in order to investigate, prevent and manage early CVD in this population.

Influence of drugs on prison suicide - A retrospective case study

The prevalence of mental disorders and comorbidity with substance abuse and personality disorders is high in prisoners. Furthermore, drug abuse in prison is a widespread problem throughout prisons around the world. In this retrospective study, we analyzed the prison deaths over six years (2012-2017). For each death, we collected data of the Berlin prison system, the prison hospital and the State Institute for Forensic and Social Medicine Berlin and the Institute of Legal Medicine and Forensic Sciences, Charité Medical University Berlin. In total, 33 prisoners died during our study period, of which 24 committed suicide. In 25% of the suicide cases, forensic toxicology reports were positive for drugs without cases of lethal intoxication. A direct influence of drug intoxication on prisoner deaths and suicide was not common in our data. Small sample size, a missing control group, and the retrospective study design limit generalizability of the results.

Chronic kidney disease in patients with obstructive sleep apnea. A narrative review

Prevalence of both chronic kidney disease (CKD) and obstructive sleep apnea (OSA) is continuously increasing. Moreover, the prevalence of OSA increases as kidney function declines and is higher among patients with end-stage renal disease (ESRD). In addition, OSA is recognized as a potential nontraditional risk factor for development and progression of CKD. Continuous positive airway pressure (CPAP) plays a pivotal role in the management of OSA, eliminating patients' symptoms and improving their quality of life. Recent studies suggested that CPAP treatment may have beneficial effects on kidney function among patients with OSA. This narrative review summarizes the existing knowledge on the association between CKD and OSA, with emphasis on the epidemiology, the pathophysiology of the development of CKD in OSA and vice versa, as well as the effect of CPAP on renal function.

Reduced Serum Vitamin D Levels Are Associated with Insulin Resistance in Patients with Obstructive Sleep Apnea Syndrome

Background and objectives: Obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular and metabolic risk factors, such as insulin resistance. Furthermore, OSAS has been associated with decreased levels of vitamin D (Vit D). The aim of the study was to assess the association between Vit D levels (expressed as 25(OH)D serum levels) and insulin resistance in patients with OSAS. Materials and Methods: Serum 25(OH)D levels were measured in consecutive subjects who had undergone polysomnography and pulmonary function testing. OSAS patients were divided into those with (homeostatic model assessment [HOMA-IR] ≥ 2) and without insulin resistance (HOMA-IR < 2). Results: Overall, 92 patients (81 males) were included in the study. OSAS patients with insulin resistance significantly differed from those without insulin resistance in terms of the body-mass index (BMI) (36.3 ± 5.8 compared to 32 ± 5.6 kg/m², respectively, p = 0.001), apnoea-hypopnoea index (AHI) (57.4 ± 28.9 compared to 40.9 ± 27.9 events/h, respectively, p = 0.009) and indices of hypoxia during sleep. Patients with OSAS and insulin resistance had lower levels of serum 25 (OH) D compared with OSAS but without insulin resistance (19.3 ± 11.5 vs 26.7 ± 12.2 ng/mL, respectively, p = 0.005). Regression analysis demonstrated a negative association of 25(OH)D levels (β = −0.048, odds ratio [OR]: 0.953, 95% confidence interval [CI]: 0.913–0.995, p = 0.030) and a positive association of BMI (β = 0.110, OR: 1.116, 95% CI: 1.007–1.237, p = 0.036) with insulin resistance. Conclusions: Vit D insufficiency was significantly more frequent among OSAS patients with insulin resistance. Both low 25(OH)D levels and high BMI were associated with the risk of insulin resistance in this population.

Vitamin D Levels in Middle-Aged Patients with Obstructive Sleep Apnoea Syndrome

BACKGROUND

Vitamin D (Vit D) insufficiency has been implicated in the pathophysiology of numerous diseases. Obstructive sleep apnoea syndrome (OSAS), a disorder associated with increased cardiovascular and cerebrovascular morbidity, has been associated with decreased Vit D levels, but reports are inconclusive.

AIM

To evaluate the association between serum 25-hydroxyvitamin D [25(OH)D], a marker of Vit D status, with anthropometric and sleep characteristics of OSAS patients and to compare those levels between OSAS patients and non-apnoeic controls.

METHOD

Consecutive subjects who had undergone polysomnography and pulmonary function testing were divided into controls (apnoea-hypopnea index, AHI <5/h) and OSAS group (AHI ≥5/h).

RESULTS

A total of 169 subjects (135 men) were included. OSAS patients (n=139) significantly differed from non-apnoeic controls in terms of age (53.9±12.8 vs. 44.9±12.8 years, p=0.002) and body mass index (BMI) (35.9±6.9 vs. 29.9±6.8 kg/m2, p<0.001). Serum 25(OH)D levels were lower in OSAS patients (17.8±7.8 vs. 23.9±12.4 ng/ml, p=0.019). In OSAS patients, levels of serum 25(OH)D were negatively correlated with sleep stage transitions (r=-0.205, p=0.028), AHI (r=-0.187, p=0.045), oxygen desaturation index (r=-0.234, p=0.011) and percentage of time with oxyhaemoglobin saturation <90% (r=-0.172, p=0.041). In contrast, they were positively correlated with average oxyhaemoglobin saturation during sleep (r=0.179, p=0.033), forced expiratory volume in 1 sec (r=0.207, p=0.037) and oxygen partial pressure (r=0.197, p=0.029).

CONCLUSION

Vit D levels were lower in OSAS patients compared with non-apnoeic controls. Several indices of OSAS severity also correlated with Vit D levels.

Corrigendum: Violent Behavior During Psychiatric Inpatient Treatment in a German Prison Hospital

[This corrects the article DOI: 10.3389/fpsyt.2019.00762.].

Violent Behavior During Psychiatric Inpatient Treatment in a German Prison Hospital

Violent behavior in correctional facilities is common and differs substantially in type, target, implication, and trigger. Research on frequency and characteristics of violent behavior in correctional facilities and psychiatric hospitals is limited. Results from recent research suggest that comorbidity of severe mental disorder, personality disorder, and diagnosis of substance abuse is related to a higher risk of violent behavior. In the Berlin prison hospital, a database was created to collect data from all violent incidences (n=210) between 1997 and 2006 and between 2010 and 2016. In a retrospective, case-control study, we analyzed specific socioeconomic data and psychiatric diagnosis and compared the group of prisoners with violent behavior with randomly selected prisoners of the same department without violent behavior (n = 210). Diagnosis of schizophrenia, non-German nationality, no use of an interpreter, no children, and no previous sentence remained significantly associated with the dependent variable violent behavior. There were no significant differences regarding age and legal statuses. Practical implications for clinical work are discussed.

Mean Platelet Volume and Platelet Distribution Width in Patients With Obstructive Sleep Apnea Syndrome and Concurrent Chronic Obstructive Pulmonary Disease

Evidence suggests that there is platelet activation in obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD). Our objective is to evaluate mean platelet volume (MPV) and platelet distribution width (PDW) in patients with overlap syndrome (OS), that is, concurrent COPD with OSAS. Mean platelet volume and PDW were assessed in consecutive patients who had undergone polysomnography and pulmonary function testing. They were divided into the following groups: controls (apnea-hypopnea index [AHI] <5/hour, and forced expiratory volume in 1st second [FEV₁]/forced vital capacity [FVC] >70%), OSAS group (AHI ≥5/hour and FEV₁/FVC >70%), and OS group (AHI ≥5/hour and FEV₁/FVC <70%). A total of 485 patients (360 males and 125 females) were included. Mean platelet volume in controls was lower compared with the other groups: 10 ± 0.9 fL for controls versus 10.3 ± 1.2 fL for OSAS ( P = .006), versus 10.7 ± 1 fL for OS ( P < .001). Additionally, MPV was higher in OS group than OSAS: 10.7 ± 1 fL versus 10.3 ± 1.2 fL, respectively ( P = .002). Platelet distribution width was lower in controls compared with the other groups: 12.9 ± 2 fL for controls versus 13.6 ± 1.9 fL for OSAS ( P = .007), versus 13.8 ± 2.3 fL for OS ( P = .008), while there was no difference between OS and OSAS groups. Mean platelet volume and PDW are increased in patients with OS compared with healthy controls, with respiratory function being the major contributor in platelet activation in this series.

Serum levels of NGAL and cystatin C as markers of early kidney dysfunction in patients with obstructive sleep apnea syndrome

PURPOSE

Obstructive sleep apnea syndrome (OSAS) has been recently proposed as an independent risk factor for chronic kidney disease. Cystatin C (Cyst C) and neutrophil gelatinase-associated lipocalin (NGAL) are novel biomarkers for the earlier detection of latent kidney disease. The aim of the study was to assess serum Cyst C and NGAL levels in otherwise healthy OSAS patients and to explore possible associations with sleep parameters.

METHODS

Consecutive subjects (n = 96, 79.2% males), without known comorbidities, with symptoms suggestive of OSAS were included. All of them underwent polysomnography (PSG) and blood examination for the measurement of serum Cyst C and NGAL levels.

RESULTS

Based on apnea-hypopnea index (AHI), subjects were classified into two groups: 32 controls and 64 OSAS patients, with no significant differences in terms of age (50.1 ± 11.7 vs 51 ± 12.2 years, p = 0.747) and BMI (33.9 ± 8.8 vs 35.9 ± 13.1 kg/m², p = 0.449). Serum Cyst C and NGAL mean levels were higher in OSAS patients compared to those in controls (1155.2 ± 319.3 vs 966.8 ± 173 ng/ml, p = 0.001, and 43.7 ± 23.2 vs 35.6 ± 13.8 ng/ml, p = 0.035, respectively). After adjustment for age and BMI in OSAS patients, serum NGAL levels were associated with AHI (β = 0.341, p = 0.015) and minimum oxyhemoglobin saturation during sleep (β = - 0.275, p = 0.032), while serum Cyst C levels were associated with percentage of time with oxyhemoglobin saturation < 90% (β = 0.270, p = 0.043), average (β = - 0.308, p = 0.018), and minimum (β = - 0.410, p = 0.001) oxyhemoglobin saturation during sleep.

CONCLUSIONS

Higher risk for latent kidney disease in otherwise healthy OSAS patients is indicated. Sleep hypoxia seems to be a significant contributor in the pathogenetic process of renal dysfunction in OSAS.

Metabolic Syndrome and Vitamin D Levels in Patients with Obstructive Sleep Apnea Syndrome

BACKGROUND

Numerous studies have indicated that obstructive sleep apnea syndrome (OSAS), may contribute to the development of metabolic syndrome (MetS) and diabetes. Moreover, OSAS has been associated with lowered vitamin D (Vit D) levels, but reports are inconclusive. Aim of the study was to compare Vit D levels according to the presence of MetS and its components in OSAS patients.

METHODS

The presence of MetS was evaluated and serum 25-hydroxy vitamin D [25(OH)D] levels were measured in consecutive newly diagnosed, by polysomnography, subjects with OSAS.

RESULTS

A total of 107 subjects (88 men) with OSAS were included in the study. Patients were divided into group A (OSAS with MetS group: 55 subjects) and group B (OSAS without MetS: 52 subjects). There were no differences between the two groups in terms of age, body mass index, and sleep parameters. Patients in group A exhibited higher levels of daytime sleepiness, as expressed by Epworth Sleepiness Scale score (12 ± 5.5 vs. 9.3 ± 4.8 for groups A vs. B, p = 0.008). Serum 25(OH)D levels were significantly decreased in group A, as compared with group B (18 ± 8.6 ng/mL vs. 23.9 ± 14.1 ng/mL, respectively, p = 0.012). Group A was then subdivided in two smaller groups, according to patients' metabolic index: OSAS patients with metabolic score = 3 and OSAS patients with metabolic score >3. Serum 25(OH)D levels were higher in OSAS patients with metabolic score = 3 compared with OSAS patients with metabolic score >3 (19.8 ± 8.9 ng/mL vs. 15.1 ± 7.3 ng/mL respectively, p = 0.038).

CONCLUSIONS

OSAS patients with concurrent MetS exhibit lower serum Vit D levels, as compared with those without MetS.

Insulin Sensitivity and Insulin Resistance in Non-Diabetic Middle-Aged Patients with Obstructive Sleep Apnoea Syndrome

Background:

Obstructive sleep apnoea syndrome (OSAS) has been linked with abnormal glucose metabolism, insulin resistance (IR) and development of diabetes mellitus.

Methods:

Non-diabetic patients (n=69) with OSAS, diagnosed by polysomnography, were prospectively recruited. To evaluate IR among OSAS patients, the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and Insulin sensitivity by Quantitative Insulin sensitivity Check Index (QUICKI) were used.

Results:

HOMA-IR was positively associated with body-mass index (BMI) (ρ=0.364, p=0.002), time with oxyhaemoglobin saturation <90% (ρ=0.291, p=0.015), arousal index (ρ=0.268, p=0.027), Epworth sleepiness scale (ESS) score (ρ=0.293, p=0.019) and negatively with average oxyhaemoglobin saturation (ρ=-0.398, p=0.001) and minimum oxyhaemoglobin saturation (ρ=-0.327, p=0.006). QUICKI was positively associated with forced vital capacity (r=0.301, p=0.014), average oxyhaemoglobin saturation (r=0.443, p<0.001), minimum oxyhaemoglobin saturation (ρ=0.318, p=0.008), and negatively associated with sleep stage transitions (r=-0.266, p=0.032), oxygen desaturation index (r=-0.404, p=0.005), time with oxyhaemoglobin saturation <90% (r=-0.311, p=0.019), arousal index (r=-0.344, p=0.004) and ESS score (r=-0.299, p=0.016). After adjustment for age and BMI, HOMA-IR was associated with sleep stage transitions, time with oxyhaemoglobin saturation <90%, average oxyhaemoglobin saturation, minimum oxyhaemoglobin saturation and arousal index. QUICKI was associated with oxygen desaturation index, sleep stage transitions, ESS score, minimum oxyhaemoglobin saturation and arousal index.

Conclusions:

An independent association between OSAS and IR in patients without pre-existing diabetes mellitus was observed. Recurrent hypoxia and sleep fragmentation in OSAS are associated with IR in these patients.

ICBP90, a novel human CCAAT binding protein, involved in the regulation of topoisomerase IIalpha expression

The one-hybrid system with an inverted CCAAT box as the DNA target sequence was used to identify proteins acting on key DNA sequences of the promoter of the topoisomerase IIalpha gene. Screening of cDNA libraries from the leukemia Jurkat cell line and from the adult human thymus resulted in the isolation of a novel protein of 793 amino acids (89,758 Da). This protein has in vitro CCAAT binding properties and has been called ICBP90. Adult thymus, fetal thymus, fetal liver, and bone marrow, known as active tissues in terms of cell proliferation, are the tissues richest in ICBP90 mRNA. In contrast, highly differentiated tissues and cells such as the central nervous system and peripheral leukocytes are free of ICBP90 mRNA. Western blotting experiments showed a simultaneous expression of topoisomerase IIalpha and ICBP90 in proliferating human lung fibroblasts. Simultaneous expression of both proteins has also been observed in HeLa cells, but in both proliferating and confluent cells. Overexpression of ICBP90 in COS-1-transfected cells induced an enhanced expression of endogenous topoisomerase IIalpha. Immunohistochemistry experiments showed that topoisomerase IIalpha and ICBP90 were coexpressed in proliferating areas of paraffin-embedded human appendix tissues and in high-grade breast carcinoma tissues. We have identified ICBP90, which is a novel CCAAT binding protein, and our results suggest that it may be involved in topoisomerase IIalpha expression. ICBP90 may also be useful as a new proliferation marker for cancer tissues.

Effect of low-dose methylprednisolone on calcium balance and bone composition in rats

Glucocorticoid induced osteoporosis has been associated with high doses and it has been partially attributed to decreased absorption and to increased calcium excretion. The present study examined the effect of low but effective doses of methylprednisolone (MP) on calcium balance and on skeleton in rats. Total duration of the experiment 29 days. Thirty-one male Wistar rats (MP group) were injected with 4mg/kg body weight MP s.c. at the 1st, 11th and 20th day of the experiment and 28 rats (C group) were used as matched controls. The 1st, 11th and 20th day of the experiment rats were placed in individual metabolic cages for three days. Food and water consumption were measured at the 2nd and 3rd days after each injection; urine and faeces were collected at the same days for calcium estimation. Calcium intake and excretion after each injection was significantly lower in the MP group as compared to controls. A statistically significant positive correlation between calcium consumption and calcium excretion was found in both groups resulting in a negative final balance. Rats were killed the 29th day. Adrenal weight was statistically significant lower in MP group (p<0.001). Morphometric properties were evaluated for the right femur. No significant difference was found between the two groups. Mineral and calcium content was slightly increased in the MP group. According to these results, it seems that methylprednisolone while effective on HPA axis did not have any effect on calcium absorption and on bone calcium deposition in rats.