The clinical characteristic of catathrenia: a new look at an old issue-a systematic review of existing literature

STUDY OBJECTIVES

The International Classification of Sleep Disorders categorized catathrenia as a respiratory disorder, but there are doubts whether episodes appear during rapid eye movement (REM) sleep or the non-rapid eye movement (NREM), their duration, and symptoms. The main objectives were to identify the most common features and relations of catathrenia.

METHODS

PubMed, Embase, and Web of Science were searched according to the PRISMA 2020 guidelines. The Joanna Briggs Institute and the ROBINS-I tools were chosen to assess the risk of bias.

RESULTS

A total of 288 records were identified, 31 articles were included. The majority of the studies had a moderate risk of bias. 49.57% of episodes occurred during the NREM sleep, while 46% took place during REM. In 60.34% females, catathrenia was more common in the NREM, while in 59.26% of males was in REM sleep (p < 0.05). Females and obese individuals were found to have shorter episodes (p < 0.05). Age was inversely correlated with minimal episodes duration (r =  - 0.34). The continuous positive airway pressure (CPAP) therapy was inversely correlated with the maximal episode duration (r =  - 0.48).

CONCLUSIONS

Catathrenia occurs with similar frequency in both genders. The most frequent symptoms embraced groaning, awareness of disturbing bedpartners, and daytime somnolence-not confirmed by the Epworth Sleepiness Scale. The episodes occur more frequently in NREM than in REM sleep. Catathrenia may be considered as a sex-specific condition. The effects of CPAP treatment leading to shortening episodes duration, which may indicate the respiratory origin of catathrenia.

Artificial light and neurodegeneration: does light pollution impact the development of Alzheimer's disease?

Two multidimensional problems of recent times - Alzheimer's disease and light pollution - seem to be more interrelated than previously expected. A series of studies in years explore the pathogenesis and the course of Alzheimer's disease, yet the mechanisms underlying this pathology remain not fully discovered and understood. Artificial lights which accompany civilization on a daily basis appear to have more detrimental effects on both environment and human health than previously anticipated. Circadian rhythm is affected by inappropriate lighting conditions in particular. The consequences are dysregulation of the sleep-wake cycle, gene expression, neuronal restructuring, brain's electricity, blood flow, metabolites' turnover, and gut microbiota as well. All these phenomena may contribute to neurodegeneration and consequently Alzheimer's disease. There is an increasing number of research underlining the complexity of the correlation between light pollution and Alzheimer's disease; however, additional studies to enhance the key tenets are required for a better understanding of this relationship.

Nocturnal Hypoventilation in the Patients Submitted to Thoracic Surgery

Introduction

Nocturnal hypoventilation may occur due to obesity, concomitant chronic obstructive pulmonary disease (COPD), obstructive sleep apnea, and/or the use of narcotic analgesics. The aim of the study was to evaluate the risk and severity of nocturnal hypoventilation as assessed by transcutaneous continuous capnography in the patients submitted to thoracic surgery.

Materials and Methods

The material of the study consisted of 45 obese (BMI 34.8 ± 3.7 kg/m2) and 23 nonobese (25.5 ± 3.6 kg/m2) patients, who underwent thoracic surgery because of malignant (57 patients) and nonmalignant tumors. All the patients received routine analgesic treatment after surgery including intravenous morphine sulfate. Overnight transcutaneous measurements of CO2 partial pressure (tcpCO2) were performed before and after surgery in search of nocturnal hypoventilation, i.e., the periods lasting at least 10 minutes with tcpCO2 above 55 mmHg.

Results

Nocturnal hypoventilation during the first night after thoracic surgery was detected in 10 patients (15%), all obese, three of them with COPD, four with high suspicion of moderate-to-severe OSA syndrome, and one with chronic daytime hypercapnia. In the patients with nocturnal hypoventilation, the mean tcpCO2 was 53.4 ± 6.1 mmHg, maximal tcpCO2 was 59.9 ± 8.4 mmHg, and minimal tcpCO2 was 46.4 ± 6.7 mmHg during the first night after surgery. In these patients, there were higher values of minimal, mean, and maximal tcpCO2 in the preoperative period. Nocturnal hypoventilation in the postoperative period did not influence the duration of hospitalization. Among 12 patients with primary lung cancer who died during the first two years of observation, there were 11 patients without nocturnal hypoventilation in the early postoperative period.

Conclusion

Nocturnal hypoventilation may occur in the patients after thoracic surgery, especially in obese patients with bronchial obstruction, obstructive sleep apnea, or chronic daytime hypercapnia, and does not influence the duration of hospitalization.

The Modulation of Adipokines, Adipomyokines, and Sleep Disorders on Carcinogenesis

Obesity and sarcopenia, i.e., decreased skeletal muscle mass and function, are global health challenges. Moreover, people with obesity and sedentary lifestyles often have sleep disorders. Despite the potential associations, metabolic disturbances linking obesity, sarcopenia, and sleep disorders with cancer are neither well-defined nor understood fully. Abnormal levels of adipokines and adipomyokines originating from both adipose tissue and skeletal muscles are observed in some patients with obesity, sarcopenia and sleep disorders, as well as in cancer patients. This warrants investigation with respect to carcinogenesis. Adipokines and adipomyokines may exert either pro-carcinogenic or anti-carcinogenic effects. These factors, acting independently or together, may significantly modulate the incidence and progression of cancer. This review indicates that one of the possible pathways influencing the development of cancer may be the mutual relationship between obesity and/or sarcopenia, sleep quantity and quality, and adipokines/adipomyokines excretion. Taking into account the high proportion of persons with obesity and sedentary lifestyles, as well as the associations of these conditions with sleep disturbances, more attention should be paid to the individual and combined effects on cancer pathophysiology.

The Influence of Comorbidities on Chemokine and Cytokine Profile in Obstructive Sleep Apnea Patients: Preliminary Results

INTRODUCTION

Obstructive sleep apnea (OSA) is frequently associated with a chronic inflammatory state and cardiovascular/metabolic complications. The aim of this study was to evaluate the influence of certain comorbidities on a panel of 45 chemokines and cytokines in OSA patients with special regard to their possible association with cardiovascular diseases.

MATERIAL AND METHODS

This cross-sectional study was performed on 61 newly diagnosed OSA patients. For the measurement of the plasma concentration of chemokines and cytokines, the magnetic bead-based multiplex assay for the Luminex^® platform was used.

RESULTS

In the patients with concomitant COPD, there were increased levels of pro-inflammatory cytokines (CCL11, CD-40 ligand) and decreased anti-inflammatory cytokine (IL-10), while in diabetes, there were increased levels of pro-inflammatory cytokines (IL-6, TRIAL). Obesity was associated with increased levels of both pro-inflammatory (IL-13) and anti-inflammatory (IL-1RA) cytokines. Hypertension was associated with increased levels of both pro-inflammatory (CCL3) and anti-inflammatory (IL-10) cytokines. Increased daytime pCO₂, low mean nocturnal SaO₂, and the oxygen desaturation index were associated with increased levels of pro-inflammatory cytokines (CXCL1, PDGF-AB, TNF-α, and IL-15).

CONCLUSIONS

In OSA patients with concomitant diabetes and COPD, elevated levels of certain pro-inflammatory and decreased levels of certain anti-inflammatory cytokines may favor the persistence of a chronic inflammatory state with further consequences. Nocturnal hypoxemia, frequent episodes of desaturation, and increased daytime pCO₂ are factors contributing to the chronic inflammatory state in OSA patients.

Cardiovascular, Pulmonary, and Neuropsychiatric Short- and Long-Term Complications of COVID-19

Beginning with the various strategies of the SARS-CoV-2 virus to invade our bodies and manifest infection, and ending with the recent long COVID, we are witnessing the evolving course of the disease in addition to the pandemic. Given the partially controlled course of the COVID-19 pandemic, the greatest challenge currently lies in managing the short- and long-term complications of COVID-19. We have assembled current knowledge of the broad spectrum of cardiovascular, pulmonary, and neuropsychiatric sequelae following SARS-CoV-2 infection to understand how these clinical manifestations collectively lead to a severe form of the disease. The ultimate goal would be to better understand these complications and find ways to prevent clinical deterioration.

New biochemical, immune and molecular markers in lung cancer: Diagnostic and prognostic opportunities

Lung cancer is one of the most common neoplasms and the leading cause of cancer-related deaths worldwide. Despite recent progress in understanding the pathomechanisms of lung cancer, it is frequently associated with late diagnosis, high incidence of metastases and poor response to treatment. Thus, there is extensive research in the field of biomarkers that aims to optimize management of lung cancer. The aim of this study was to review the current perspectives of a wide spectrum of circulating molecules that seem promising as new potential biomarkers of lung cancer. Among these, biochemical (active proteins), immunological (immunocompetent cells, cytokines, chemokines, and antibodies) and genetic (circulating tumor DNA, cell-free DNA and microRNA) markers are presented and discussed. The use of these markers would support the early detection of lung cancer and might be used for predicting disease progression, response of the disease to targeted therapies, monitoring the course of treatment, and developing individualized diagnostic and therapeutic strategies. Special attention was given to potential markers of nervous system involvement in the course of lung cancer, due to its prevalence and devastating impact. Limitations of the potential biomarkers are also outlined and future directions of investigations in this field highlighted, with the aim of improving the accuracy and practical utility of these biomarkers.

The Role of Stem Cells in the Therapy of Stroke

Background: Stroke is a major challenge in neurology due to its multifactorial genesis and irreversible consequences. Processes of endogenous post-stroke neurogenesis, although insufficient, may indicate possible direction of future therapy. Multiple research considers stem-cell-based approaches in order to maximize neuroregeneration and minimize post-stroke deficits.

Objective: Aim of this study is to review current literature considering post-stroke stem-cell-based therapy and possibilities of inducing neuroregeneration after brain vascular damage.

Methods: Papers included in this article were obtained from PubMed and MEDLINE databases. The following medical subject headings (MeSH) were used: “stem cell therapy”, “post-stroke neurogenesis”, “stem-cells stroke”, “stroke neurogenesis”, “stroke stem cells”, “stroke”, “cell therapy”, “neuroregeneration”, “neurogenesis”, “stem-cell human”, “cell therapy in human”. Ultimate inclusion was made after manual review of the obtained reference list.

Results: Attempts of stimulating neuroregeneration after stroke found in current literature include supporting endogenous neurogenesis, different routes of exogenous stem cells supplying and extracellular vesicles used as a method of particle transport.

Conclusion: Although further research in this field is required, post stroke brain recovery supported by exogenous stem cells seems to be promising future therapy revolutionizing modern neurology.

Nuclear Envelope and Nuclear Pore Complexes in Neurodegenerative Diseases-New Perspectives for Therapeutic Interventions

Transport of proteins, transcription factors, and other signaling molecules between the nucleus and cytoplasm is necessary for signal transduction. The study of these transport phenomena is particularly challenging in neurons because of their highly polarized structure. The bidirectional exchange of molecular cargoes across the nuclear envelope (NE) occurs through nuclear pore complexes (NPCs), which are aqueous channels embedded in the nuclear envelope. The NE and NPCs regulate nuclear transport but are also emerging as relevant regulators of chromatin organization and gene expression. The alterations in nuclear transport are regularly identified in affected neurons associated with human neurodegenerative diseases. This review presents insights into the roles played by nuclear transport defects in neurodegenerative disease, focusing primarily on NE proteins and NPCs. The subcellular mislocalization of proteins might be a very desirable means of therapeutic intervention in neurodegenerative disorders.

Extracellular vesicles in cancer nanomedicine

To date, a lot of nanotechnological optitions are available for targeted drug delivery. Extracellular vesicles (EVs) are membrane structures that cells use for storage, transport, communication, and signaling. Recent research has focused on EVs as natural nanoparticles for drug delivery. This review sheds light on the application of EVs in cancer therapy, such as targeted chemotherapy, gene therapy, and vaccine development. Aspects of biogenesis, isolation, targeting, and loading of EVs are discussed in detail.

Sleep Disturbances and Cognitive Impairment in the Course of Type 2 Diabetes-A Possible Link

There is an increasing number of patients worldwide with sleep disturbances and diabetes. Various sleep disorders, including long or short sleep duration and poor sleep quality of numerous causes, may increase the risk of diabetes. Some symptoms of diabetes, such as painful peripheral neuropathy and nocturia, or associated other sleep disorders, such as sleep breathing disorders or sleep movement disorders, may influence sleep quality and quantity. Both sleep disorders and diabetes may lead to cognitive impairment. The risk of development of cognitive impairment in diabetic patients may be related to vascular and non-vascular and other factors, such as hypoglycemia, hyperglycemia, central insulin resistance, amyloid and tau deposits and other causes. Numerous sleep disorders, e.g., sleep apnea, restless legs syndrome, insomnia, and poor sleep quality are most likely are also associated with cognitive impairment. Adequate functioning of the system of clearance of the brain from toxic substances, such as amyloid β, i.e. glymphatic system, is related to undisturbed sleep and prevents cognitive impairment. In the case of coexistence, sleep disturbances and diabetes either independently lead to and/or mutually aggravate cognitive impairment.

Dysbiosis is one of the risk factor for stroke and cognitive impairment and potential target for treatment

More than 50 million people have various forms of cognitive impairment basically caused by neurodegenerative diseases, such as Alzheimer's, Parkinson's, and cerebrovascular diseases as well as stroke. Often these conditions coexist and exacerbate one another. The damaged area in post-stroke dementia may lead to neurodegenerative lesions. Gut microbiome functions like an endocrine organ by generating bioactive metabolites that can directly or indirectly impact human physiology. An alteration in the composition and function of intestinal flora, i.e. gut dysbiosis, is implicated in neurodegenerative and cerebrovascular diseases. Additionally, gut dysbiosis may accelerate the progression of cognitive impairment. Dysbiosis may result from obesity; metabolic disorders, cardiovascular disease, and sleep disorders, Lack of physical activity is associated with dysbiosis as well. These may coexist in various patterns in older people, enhancing the risk, incidence, and progression of cerebrovascular lesions, neurodegenerative disorders, and cognitive impairment, creating a vicious circle. Recently, it has been reported that several metabolites produced by gut microbiota (e.g., trimethylamine/trimethylamine N-oxide, short-chain fatty acids, secondary bile acids) may be linked to neurodegenerative and cerebrovascular diseases. New treatment modalities, including prebiotic and probiotics, may normalize the gut microbiota composition, change the brain-gut barrier, and decrease the risk of the pathology development. Fecal microbiota transplantation, sometimes in combination with other methods, is used for remodeling and replenishing the symbiotic gut microbiome. This promising field of research is associated with basic findings of bidirectional communication between body organs and gut microbiota that creates new possibilities of pharmacological treatments of many clinical conditions. The authors present the role of gut microbiota in physiology, and the novel therapeutic targets in modulation of intestinal microbiota Personalized therapies based on their personal genome make up could offer benefits by modulating microbiota cross-talk with brain and cardiovascular system. A healthy lifestyle, including pre and probiotic nutrition is generally recommended. Prevention may also be enhanced by correcting gut dysbiosis resulting a reduced risk of post-stroke cognitive impairment including dementia.

The Links between Parkinson's Disease and Cancer

Epidemiologic studies indicate a decreased incidence of most cancer types in Parkinson’s disease (PD) patients. However, some neoplasms are associated with a higher risk of occurrence in PD patients. Both pathologies share some common biological pathways. Although the etiologies of PD and cancer are multifactorial, some factors associated with PD, such as α-synuclein aggregation; mutations of PINK1, PARKIN, and DJ-1; mitochondrial dysfunction; and oxidative stress can also be involved in cancer proliferation or cancer suppression. The main protein associated with PD, i.e., α-synuclein, can be involved in some types of neoplastic formations. On the other hand, however, its downregulation has been found in the other cancers. PINK1 can act as oncogenic or a tumor suppressor. PARKIN dysfunction may lead to some cancers’ growth, and its expression may be associated with some tumors’ suppression. DJ-1 mutation is involved in PD pathogenesis, but its increased expression was found in some neoplasms, such as melanoma or breast, lung, colorectal, uterine, hepatocellular, and nasopharyngeal cancers. Both mitochondrial dysfunction and oxidative stress are involved in PD and cancer development. The aim of this review is to summarize the possible associations between PD and carcinogenesis.

The Association of Sleep Disorders, Obesity and Sleep-Related Hypoxia with Cancer

BACKGROUND

Sleep disorders have emerged as potential cancer risk factors.

OBJECTIVE

This review discusses the relationships between sleep, obesity, and breathing disorders with concomitant risks of developing cancer.

RESULTS

Sleep disorders result in abnormal expression of clock genes, decreased immunity, and melatonin release disruption. Therefore, these disorders may contribute to cancer development. Moreover, in sleep breathing disorder, which is frequently experienced by obese persons, the sufferer experiences intermittent hypoxia that may stimulate cancer cell proliferation.

DISCUSSION

During short- or long- duration sleep, sleep-wake rhythm disruption may occur. Insomnia and obstructive sleep apnea increase cancer risks. In short sleepers, an increased risk of stomach cancer, esophageal squamous cell cancer, and breast cancer was observed. Among long sleepers (>9 hours), the risk of some hematologic malignancies is elevated.

CONCLUSION

Several factors including insomnia, circadian disruption, obesity, and intermittent hypoxia in obstructive sleep apnea are contributing risk factors for increased risk of several types of cancers. However, further studies are needed to determine the more significant of these risk factors and their interactions.

The Relationship between Sleep Bruxism and Obstructive Sleep Apnea Based on Polysomnographic Findings

Obstructive sleep apnea (OSA) is the most common sleep disorder. Sleep bruxism (SB) is a masticatory muscle activity during sleep that commonly co-occurs with OSA. The presented study aimed to assess this relationship and to identify factors affecting this co-occurrence. Adult patients (n = 110) were evaluated for OSA and SB in a sleep laboratory using polysomnography. The episodes of bruxism and respiratory events were scored according to the standards of the American Academy of Sleep Medicine. The prevalence of OSA and SB was found to be 86.37% and 50%, respectively. The bruxism episode index (BEI) was increased in the group with mild and moderate OSA (apnea–hypopnea index (AHI) <30) compared to that in the group with severe OSA (AHI ≥ 30) (5.50 ± 4.58 vs. 1.62 ± 1.28, p < 0.05). A positive correlation between AHI and BEI was observed in the group with AHI < 30. Regression analysis indicated that higher AHI, male gender, and diabetes were independent predictors for the increased BEI in group with AHI < 30. The relationship between OSA and SB depends on the degree of severity of OSA. OSA is correlated with SB in mild and moderate cases of OSA in the group of patients with increased risk of OSA.

Acceptance of Illness Associates with Better Quality of Life in Patients with Nonmalignant Pulmonary Diseases

Chronic nonmalignant pulmonary diseases impose a heavy burden on patients, generate health-care costs, and contribute to poor health-related quality of life. It has been found that a wide range of factors negatively affects quality of life, but the role of acceptance of illness needs to be further investigated. The aim of the study was to evaluate the relationship between acceptance of illness and quality of life in patients with chronic nonmalignant pulmonary diseases. The study encompassed 200 patients of the mean age 58 ± 16 years who were mainly diagnosed with asthma (n = 72; 36%), COPD (n = 52; 26%), and obstructive sleep apnea (n = 38; 19%). The patients answered the Acceptance of Illness Scale (AIS) and the St. George's Respiratory Questionnaire (SGRQ). Sociodemographical and clinical data were collected. The level of acceptance of illness significantly associated with each of the SGRQ domains. The greater the acceptance of illness, the lowest was the SGRQ score. The mean total score of SGRQ was 44.6 ± 24.9 and that of AIS was 26.1 ± 8.2. Higher AIS scores significantly associated with lower SGRQ scores, i.e., with better quality of life (p < 0.001 for each domain). We conclude that in patients with chronic nonmalignant pulmonary diseases, acceptance of illness plays an important role and is closely related to the general level of quality of life. Interventions aimed at improving acceptance of illness may be considered to improve quality of life.

Quality of Life in Patients with Advanced Non-Small-Cell Lung Cancer Receiving Palliative Chemotherapy

The goal of this study was to explore quality of life in patients with advanced non-small-cell lung cancer (NSCLC) in an attempt to single out features that could help predict the possibility of non-completion of chemotherapy. The survey tool was the Quality of Life Questionnaire Core-30 (QLQ-C30) with the module Lung Cancer 13 (LC-13) developed by the European Organization for Research and Treatment of Cancer. The assessment of quality of life (QoL) was performed in 58 patients with advanced NSCLC before palliative chemotherapy and it was repeated in 43 patients who completed at least three cycles of chemotherapy. We found that the patients who failed to complete the chemotherapy course distinctly showed, in contradistinction to those who completed it, poor physical functioning in (67.6 ± 16.3 vs. 78.3 ± 21.3 points, respectively, p < 0.05) and the lack of appetite (27.1 ± 38.0 vs. 48.9 ± 37.5 points, respectively p < 0.05). At the end of palliative chemotherapy alopecia, sore throat, and constipation significantly worsened QoL, but global health status remained unchanged. In conclusion, poor physical functioning and loss of appetite seem to harbinger a risk of non-completion of chemotherapy in advanced NSCLC.

WITHDRAWN: Association Between Alzheimer’s Disease and Cancer - A Short Overview

The following article has been withdrawn at the request of the authors and editor of the journal Current Medicinal Chemistry: Title: Association between Alzheimer's Disease and Cancer - A Short Overview. Authors: Katarzyna Szczechowiak, Anna Brzecka, Naomi Hachiya, Joanna Wyka and Jerzy Leszek* Bentham Science apologizes to the readers of the journal for any inconvenience this may cause. Bentham Science Disclaimer: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

Increased Pain Sensitivity in Obese Patients After Lung Cancer Surgery

Background: Obesity and cancer are recognized worldwide health threats. While there is no reported causal relationship, the increasing frequency of both conditions results in a higher incidence of obese patients who are being treated for cancer. Physiological data indicate that there is a relationship between obesity and susceptibility to pain; however, currently, there are no specific pharmacological interventions.

Objective: To evaluate the self-reported intensity of postoperative pain in obese and nonobese lung cancer who receive either thoracotomy or video-assisted thoracic surgery (VATS) surgical therapy.

Material and Methods: In 50 obese [mean body mass index (BMI) of 34.1 ± 3.2 kg/m²] and 62 nonobese (mean BMI of 24.9 ± 3 kg/m²) lung cancer patients, the intensity of pain was estimated every 4 h using a visual analog scale (VAS, 0 indicating no pain and 10 indicating “worst imaginable pain”) beginning shortly after surgery (Day O) and continuing until the day of discharge (Day D).

Results: The self-reported pain was more severe in obese than in nonobese patients, both at the time of the operation [Day O (4.5 ± 1.2 vs 3.4 ± 1.1; p < 0.0001)] and at the day of discharge [Day D (3.9 ± 1.4 vs 2.6 ± 0.9, p < 0.0001)]. This finding was consistent both in the patients after thoracotomy and after video-assisted thoracic surgery (VATS, p < 0.0001). The patients with severe pain shortly after surgery (VAS score >4) had significantly higher BMI (31.8 ± 5.6 kg/m²vs 28.8 ± 5.2 kg/m², p < 0.01) and were hospitalized longer than the remaining patients (13.0 ± 13.6 days vs 9.5 ± 3.6 days, p < 0.05).

Conclusion: The reported perception of pain in obese lung cancer patients is greater than in nonobese patients undergoing the same thoracic surgery. In obese patients, severe pain persisted longer. Pain management is an important consideration in the postoperative care of lung cancer patients, even more so with obese patients.

ECCR1 and NFKB2 Polymorphisms as Potential Biomarkers of Non-small Cell Lung Cancer in a Polish Population

BACKGROUND/AIM

Although genetic factors are presumed to account only for a part of the inter-individual variation in lung cancer susceptibility, the results are conflicting and there are no data available regarding the Polish population. We, therefore, performed a case-control study to investigate the association of seven selected single nucleotide polymorphisms (SNPs), in genes coding for excision repair cross-complimentary group 1 (ERCC1: rs11615, rs3212986, rs2298881), nuclear factor ĸB (NFKB2: rs7897947, rs12769316), bone morphogenetic protein 4 (BMP4: rs1957860), complement receptor 1 (CR1: rs7525160) and del/ins polymorphism in the family hypoxia inducible factor 2 gene (EGLN2: rs10680577), with non-small cell lung cancer (NSCLC) risk.

MATERIALS AND METHODS

Real-time PCR with melting curve analysis was used for genotyping of NSCLC patients and healthy individuals of Polish origin.

RESULTS

The ERCC1 rs11615 T allele and rs3212986 GG homozygosity were found to be associated with a higher risk of developing NSCLC. In addition, NFKB2 rs12769316 GG homozygosity was more frequently detected among male patients than controls, while no significant differences were found between the five polymorphisms.

CONCLUSION

ERCC1 polymorphisms may affect NSCLC risk in the Polish population, while the NFKB2 variant may be a possible marker of the disease in males.

Sleep Disorders Associated With Alzheimer's Disease: A Perspective

Sleep disturbances, as well as sleep-wake rhythm disturbances, are typical symptoms of Alzheimer's disease (AD) that may precede the other clinical signs of this neurodegenerative disease. Here, we describe clinical features of sleep disorders in AD and the relation between sleep disorders and both cognitive impairment and poor prognosis of the disease. There are difficulties of the diagnosis of sleep disorders based on sleep questionnaires, polysomnography or actigraphy in the AD patients. Typical disturbances of the neurophysiological sleep architecture in the course of the AD include deep sleep and paradoxical sleep deprivation. Among sleep disorders occurring in patients with AD, the most frequent disorders are sleep breathing disorders and restless legs syndrome. Sleep disorders may influence circadian fluctuations of the concentrations of amyloid-β in the interstitial brain fluid and in the cerebrovascular fluid related to the glymphatic brain system and production of the amyloid-β. There is accumulating evidence suggesting that disordered sleep contributes to cognitive decline and the development of AD pathology. In this mini-review, we highlight and discuss the association between sleep disorders and AD.

[Coexistence of asthma and obstructive sleep apnea syndrome - review of the literature]

Both asthma and obstructive sleep apnea (OSA) syndrome are frequent diseases and their coexistence may implicate important consequences. The incidence of OSA syndrome among the patients with asthma is higher than in the general population, especially in the patients with nocturnal symptoms persisting despite treatment, in patients frequently admitted to hospital because of the exacerbations of asthma, and in obese patients. The causes of frequent coexistence of asthma and OSA syndrome are not fully elucidated. The common abnormalities possibly linking asthma and OSA syndrome include obesity, gastro-esophageal reflux, nasal obstruction, and inflammation. In some patients with asthma it would be advised to search for OSA syndrome, as obstructive sleep apneas and hypopneas may influence asthma exacerbations. Especially, OSA should be suspected in the asthma patients with the signs of ventilatory disturbances during sleep. The method of choice of treatment of the patients with OSA syndrome is continuous positive airway pressure (CPAP) applied through the nasal or full-face mask, that leads to elimination of the obstructive sleep apneas and hypopneas during sleep. CPAP treatment may also positively influence the course of asthma.

Coexistence of asthma and the obesity-hypoventilation syndrome

OBJECTIVE

Introduction: With the increasing problem of obesity in the world, high prevalence of asthma in obese persons and high prevalence of sleep breathing disorders related to obesity, the number of patients with coexisting asthma and obesity hypoventilation syndrome is likely to increase. The aim: To evaluate long-term effects of obesity hypoventilation syndrome treatment in the patients with concomitant asthma.

PATIENTS AND METHODS

Materials and methods: Obesity hypoventilation syndrome was diagnosed in six adult patients with asthma (body mass index 43.2±5.84 kg/m2, diurnal PaCO2 53.8±8.9 mmHg, apnea/hypopnea index 82±12.8/hour, mean SaO2 during sleep 77.7±6.6%). Four patients were treated with continuous positive airway pressure (CPAP) and two patients - with non-invasive ventilation (NIV). The patients were followed-up for 36±19 months.

RESULTS

Results: During the follow-up period daytime PaCO2 decreased to normal values, mean SaO2 during sleep increased to 93±3.1%, p<0.001. No asthma exacerbations were observed. In two patients significant reduction of anti-asthmatic treatment was observed, including withdrawal of chronic oral corticosteroid treatment.

CONCLUSION

Conclusions: Obese asthmatic patients with chronic respiratory insufficiency should be checked for concomitant obesity hypoventilation syndrome. Positive airway pressure treatment during sleep (CPAP or NIV) in asthmatic patients with obesity hypoventilation syndrome is well tolerated, leads to reversal of chronic respiratory insufficiency and in some patients may contribute to the improvement of asthma control.

Influence of Obesity on the Course of Malignant Neoplastic Disease in Patients After Pulmonary Metastasectomy

BACKGROUND/AIM

The aim of the study was to determine whether increased body mass index (BMI) in patients operated on for lung metastases influences the course of the disease.

MATERIALS AND METHODS

The retrospective data of 97 patients previously operated on for different malignancies were analyzed. There were 40 obese patients (BMI >30 kg/m², mean 33.9±4.5) and 57 non-obese patients (BMI 25.8±2.7 kg/m², p<0.001). Disease-free interval (DFI), the overall survival (OS) and survival after pulmonary metastasectomy were analyzed.

RESULTS

DFI and OS were longer in obese than in non-obese patients (82.1±83.5 months vs. 43.0±44.4, p<0.01 and 110.7±81.3 months vs. 69.9±52.9 p<0.005, respectively). Survival after pulmonary metastasectomy was 27.2±25.6 months and was longer in obese and overweight patients than in normal weight patients (20.2±18.4 months vs. 29.4±26.5, p<0.05).

CONCLUSION

Being obese or overweight is a favorable prognostic factor in patients after surgical resection of lung metastases of different malignancies.

Obesity Paradox in the Course of Cerebrovascular Diseases

Obesity remains an important risk factor of cardiovascular and cerebrovascular diseases. However, it has been observed that increased body fat and body mass index predicted longer survival after the occurrence of a cardiovascular event. This observation has been named the obesity paradox. Initially, the term obesity paradox referred to the observation of the better outcome of cardiovascular diseases, such as heart failure and coronary heart disease, in obese patients as compared to underweight and normal-weight patients. Recently, similar, although fewer, observations confirm the occurrence of the obesity paradox in patients with acute cerebrovascular diseases. The underlying reasons for the protective effects of excessive body fat tissue against the consequences of acute cardiovascular and cerebrovascular diseases are poorly understood. The effect of preconditioning may be associated with the obesity paradox. The issue of the correlation between obesity and better survival of patients with cardiovascular and cerebrovascular diseases still remains largely unexplored. Debates for and against the obesity paradox continue.

Sclerostin in Obstructive Sleep Apnea

Sclerostin, a glycoprotein involved in vascular calcification, could play a role in cardiovascular disorders. Obstructive sleep apnea (OSA) is frequently associated with cardiovascular comorbidities. Thus, in this study we set out to assess the level of sclerostin in patients with OSA. Sclerostin was evaluated in the serum by ELISA method in 106 patients (43 women) with OSA of the mean age of 55 ± 10 years, BMI of 33.1 ± 7.9 kg/m(2), and apnea/hypopnea index (AHI) of 29.7 ± 18.9. There were 76 (72 %) patients with cardiovascular comorbidities in the OSA group. The results were compared with those in 49 healthy control subjects. We found that the level of sclerostin was higher in the female OSA patients than that in female controls (80.1 ± 36.5 pg/ml vs. 61.4 ± 24.1 pg/ml; p < 0.05) and it correlated with AHI (rs = 0.32, p < 0.01) and desaturation index (rs = 0.34, p < 0.01). Further, in OSA women with cardiovascular comorbidities, sclerostin was higher than in women without such comorbidities (87.0 ± 37.4 pg/ml vs. 57.3 ± 22.1 pg/ml; p < 0.05). In men, there were no differences in the serum sclerostin level between the OSA and control subjects, nor was there any relationship with cardiovascular diseases. In conclusion, increased serum sclerostin coincides with the severity of OSA and its cardiovascular sequelae in female patients.

[Smoking among patients with obstructive sleep apnea syndrome--preliminary report]

Association of smoking with the occurrence and severity of the obstructive sleep apnea syndrome (OSAS) is poorly understood.

THE AIM OF THE STUDY

The evaluation of smoking habits among the patients hospitalized with the suspicion and diagnosis of the OSAS. The possible relationship between smoking and severity of OSAS and the occurrence of concomitant diseases occurrence was also evaluated.

MATERIAL AND METHODS

82 patients has been included into the study: 11 without OSAS (apnea/hypopnea index-AHI < 5/hour) and 71 with OSAS of varying severity (AHI 7-74/hours).

RESULTS

Forty six patients with OSAS were smokers or ex-smokers, and 5 persons from a group without OSAS were ex-smokers. Patients with OSAS who smoked at least 20 pack years had significant higher AHI (54.5/h) than non-smokers (38.5/h) and patients smoking less than 20 pack years (35.9/h). These groups of patients did not differ according to BMI (36.8 kg/m2, 38.8 kg/m2, 36.3 kg/ms). Smokers with OSAS more frequently had concomitant cardiovascular diseases than non-smokers with OSAS (86.1% and 23.1% respectively).

CONCLUSION

Smoking influences the severity of OSAS independently of the degree of obesity.

Nocturnal parasympathetic modulation of heart rate in obesity-hypoventilation patients

Heart rate variation (HRV) reflects the activity of the autonomic nervous system. The aim of the study was to analyze HRV in obstructive sleep apnea (OSA) and obesity hypoventilation (OH) patients to answer the question of whether chronic alveolar hypoventilation influences autonomic heart rate regulation. In 41 patients, diagnosed with either 'pure' OSA (n=23, apnea/hypopnea index--AHI: 43.8±18.0 PaCO2≤45 mmHg) or OH syndrome (n=18, AHI 58.7±38.0 PaCO2>46 mmHg), the HRV was analyzed, based on an 8 h ECG recording during sleep. In the OH patients, compared with the OSA patients, there was a globally decreased HRV, with a corresponding decrease in high frequency power in the spectral analysis of HRV and increased low frequency/high frequency ratio (p<0.05), indicating a reduced parasympathetic and increased sympathetic heart rate modulation. We conclude that hypoxemia and hypercapnia of the sleep disordered breathing have an impact on the autonomic heart rate regulation. HRV indices have a potential to become prognostic factors for the development of cardiovascular complications in patients with sleep disordered breathing.

Soluble ligand CD40 and uric acid as markers of atheromatosis in patients with obstructive sleep apnea

The aim of the study was to evaluate the risk of atheromatosis in patients with obstructive sleep apnea (OSA), as based on the concentration of the pro-atherogenic soluble CD40L ligand (sCD40L) in relation to the level of uric acid. The serum levels of sCD40L and uric acid were measured in 79 OSA patients (mean apnea/hypopnea index - AHI 34.4 ± 20.9) and in 40 healthy controls. We found that sCD40L was higher in the OSA patients with hyperuricemia than that in the patients with uric acid in the normal range (sCD40L: 9.0 ng/ml vs. 8.0 ng/ml, respectively, p < 0.05). There was a positive association of sCD40L with AHI (p = 0.01) and a negative one with the mean minimal nocturnal SaO₂(p < 0.05). Uric acid correlated negatively with the mean and minimal SaO₂and positively with the oxygen desaturation index (p < 0.05). OSA patients with hyperuricemia also had a higher prevalence of hypertension and ischemic heart disease. We conclude that OSA patients with increased uric acid concentration have increased risk of atheromatosis, as indicated by a higher level of soluble pro-atherogenic ligand CD40, and a higher prevalence of cardiovascular adverse events.

Zalecenia Polskiego Towarzystwa Chorób Płuc Dotyczące Rozpoznawania i Leczenia Zaburzeń Oddychania w Czasie snu (ZOCS) u Dorosłych

Sen jest stanem fizjologicznym, w którym człowiek spędza około jednej trzeciej życia—niezbędnym dla prawidłowego funkcjonowania organizmu [...]

Efficacy of noninvasive mechanical ventilation in obese patients with chronic respiratory failure

Chronic respiratory failure (CRF) develops in a minority of obese patients. Noninvasive mechanical ventilation (NIMV) is a new optional treatment for such patients. The aim of this study was to evaluate the effectiveness of NIMV in obese patients with CRF. The material of the study consisted of 34 obese patients (body mass index 47.3 ± 7.9 kg/m(2)) with CRF (PaO2 = 6.40 ± 0.93 kPa and PaCO2 = 8.67 ± 2.13 kPa) who were hypoxemic despite an optimal therapy. Thirteen patients had an overlap syndrome (OS) - chronic obstructive pulmonary disease (COPD) coexisting with obstructive sleep apnea syndrome (OSAS) and 21 patients had obesity-hypoventilation syndrome (OHS). Ventilation parameters were determined during polysomnography. The efficacy of NIMV was evaluated on the fifth day and after 1 year's home treatment. We observed a significant increase in the mean blood oxygen saturation during sleep in all patients; the increase was greater in patients with OHS (92.6 ± 1.4 %) than in patients with OS (90.4 ± 1.8 %). There was a significant improvement of diurnal PaO2 and PaCO2 on the fifth day of NIMV (mean PaO2 increase 2.1 kPa and PaCO2 decrease 0.9 kPa) and also after 1 year of home NIMV (mean PaO2 increase 1.9 kPa and PaCO2 decrease 2.4 kPa). Only one patient stopped treatment because of lack of tolerance during the observation period (1-3 years). In conclusion, NIMV is an effective and well tolerated treatment option in obese patients with CRF resulting in a rapid relief of respiratory disorders during sleep and a gradual, long-term improvement of gas exchange during the day, particularly in patients with OHS.

[Concentrations of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinases-1 in serum of patients with chronic obstructive pulmonary disease]

Chronic obstructive pulmonary disease (COPD) is characterized by the progressive destruction of the extracellular matrix of the lung. Matrix metalloproteinases (MMPs) and their inhibitors, especially tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), play a central role in the lung remodeling in COPD. Their concentrations in the sputum and bronchoalveolar lavage are considered as a sign of the local inflammation in COPD patients. The aim of the study was to evaluate of the MMP-9 and TIMP-1 serum concentration in COPD patients with respect to the correlation with a systemic inflammatory process.

MATERIAL AND METHODS

Thirty six COPD patients (29 male and 7 female) were enrolled into the study. Age-matched, healthy 15 subjects (11 male and 4 female) were selected as a control group. Serum levels of MMP-9, TIMP-1 and CRP were measured. The pre- and post-bronchodilator forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio were determined. The Spearman correlation was performed.

RESULTS

The serum MMP-9 concentration was significantly higher in the COPD patients than that in the control group (COPD: 194.8 +/- 129.1 ng x ml(-1); control subjects: 11.7 +/- 2.1 ng x ml(-1); p < 0.001). The serum concentration of CRP was significantly higher in the COPD patients than that in the control group (COPD: 14.3 +/- 6.3 ng x ml(-1); control subjects: 6.2 +/- 2.8 ng x ml(-1); p < 0.001). There was statistically significant correlation between the MMP-9 concentration and the CRP level in the serum of patients with COPD (p < 0.01; r = 0.45). There were no significant differences in the serum TIMP-1 concentrations between the control group and COPD patients. There was statistically significant, negative correlation between the FEV1 % of predicted value and the MMP-9 concentration (p = 0.03; r = -0.43).

CONCLUSIONS

MMP-9 may play an important role in the systemic inflammatory process in COPD. The serum concentrations of MMP-9 correlate with the stage of COPD.

Coexistence of Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease

Background: Obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) may lead to chronic alveolar hypoventilation. The coexistence of OSA and COPD has been termed the ‘overlap syndrome’. The aim of the study was to determine the relationship between the severity of COPD and the occurrence of chronic alveolar hypoventilation in patients with OSA and to evaluate the impact of chronic alveolar hypoventilation in patients with the overlap syndrome on the severity of breathing disorders during sleep. Material and methods: The study included 64 obese patients (BMI 40.0 ± 6.5 kg/m2) with OSA (AHI > 15; mean AHI 52 ± 22) coexisting with COPD. We analysed the results of polysomnography, spirometry and arterial blood gas analysis. Results: Chronic alveolar hypoventilation was present in 67% of the patients, including 60.5%, 85% and 100% of patients with moderate, severe and very severe COPD by spirometry, respectively. Patients with chronic alveolar hypoventilation had lower values of FVC (2.7 ± 0.8 l vs. 3.6 ± 0.9 l; p < 0.001), FEV1 (1.7 ± 0.6 l vs. 2.2 ± 0.5 l; p < 0.001) and mean SaO2 at the end of obstructive sleep apneas and hypopneas (75% ± 10% vs. 84% ± 5%; p < 0.001). Conclusions: Chronic alveolar hypoventilation is observed in the majority of obese patients with moderate to severe OSA and coexisting COPD, including moderate COPD. The occurrence of chronic alveolar hypoventilation in obese patients with OSA coexisting with COPD is associated with a marked arterial hypoxia during obstructive sleep apneic and hypopneic episodes.

Suppresion of Chronic Nocturnal Cough during Continuous Positiveairway Pressure (CPAP) Treatment in a Patient with Asthma Andobstructive Sleep Apnoea Syndrome

Sleep disruption may develop in patients suffering from chronic cough and in patients with obstructive sleep apnoea syndrome (OSAS). An increasing number of reports are being published that suggest a relationship between chronic nocturnal cough and the occurrence of breathing disorders during sleep characteristic of OSAS. We report a case of a 59-year-old obese male (BMI 38.6 kg/m2) suffering from asthma and chronic nocturnal cough irresponsive to optimal asthma treatment. Based on an examination of the patient’s breathing function during sleep we established the diagnosis of moderate OSAS and initiated continuous positive airway pressure (CPAP) treatment, as a result of which the cough resolved. The successful outcome of using CPAP in preventing episodes of nocturnal cough was further confirmed after a year of CPAP use. This case report justifies the inclusion of OSAS in the differential diagnosis of nocturnal cough, including nocturnal cough in asthma patients. The use of CPAP, which prevents the development of apnoeas and hypopnoeas, may also lead to the resolution of chronic nocturnal cough.

[Suppression of chronic nocturnal cough during continuous positive airway pressure (CPAP) treatment in a patient with asthma and obstructive sleep apnea syndrome]

Sleep disruption is a common feature both in the patients with chronic cough and in the patients with obstructive sleep apnea syndrome (OSAS). There is increasing body of evidence that chronic nocturnal cough may be related to OSAS. We describe a 59 years old, obese man (BMI 38,6 kg/m(2)) with asthma and chronic nocturnal cough not responding to the optimal anti-asthmatic treatment. On the basis of nocturnal polysomnography moderate form of the OSAS has been diagnosed and the treatment with continuous positive airway pressure (CPAP) has been started. All the nocturnal symptoms, including cough, disappeared. The effect of CPAP in preventing nocturnal cough persisted at the follow-up visit after a year since diagnosis. This case indicates that nocturnal cough may be an important symptom of the OSAS and CPAP treatment - by abolishing sleep apneas and hypopneas - may also prevent chronic cough during sleep.

[Coexistence of obstructive sleep apnea syndrome and chronic obstructive pulmonary disease]

INTRODUCTION

Both obstructive sleep apnea (OSA) syndrome and chronic obstructive pulmonary disease (COPD) may lead to chronic alveolar hypoventilation. The coexistence of OSA syndrome and COPD has been named the overlap syndrome. The aim of the study was to elucidate the relationship between the severity of COPD and the occurrence of chronic alveolar hypoventilation in patients with OSA syndrome.

MATERIAL AND METHODS

The material of the study consisted of 64 obese (BMI 40 ± 5.5 kg/m(2)) patients with OSA syndrome (AHI 〉15, mean 52 ± 23) and coexisting COPD (FEV1/FVC 〈 70%). The results of polysomnographic, spirometric and arterial blood gases studies have been evaluated.

RESULTS

Chronic alveolar hypoventilation has been found in 67% of the patients: in 60.5% of patients in the spirometric stage II, in 85% of patients in the stage III and in all the patients in the stage IV of COPD. In the patients with chronic alveolar hypoventilation as compared with the remaining patiens there were: lower FVC (2.7 ± 0.8 L v. 3.6 ± 0.9 L; p 〈 0.001), FEV(1) (1.7 ± 0.6 L v. 2.2 ± 0.5 L; p 〈 0.001) and mean SaO(2) during obstructive sleep apneas and hypopneas (75 ± 10% v. 84 ± 5%; p 〈 0.001).

CONCLUSIONS

Chronic alveolar hypoventilation occurs in most of the obese patients with moderate and severe OSA syndrome and coexisting COPD, including most of the patients with moderately impaired ventilatory function. The occurrence of chronic alveolar hypoventilation in the course of the overlap syndrome is related to the restrictive ventilatory pattern and the lower mean and minimal SaO(2) during obstructive sleep apneas and hypopneas.

Fourth Polish-French Pulmonary Conference, Wrocław, October 16th–18th 2009

W dniach 16–18 października 2009 roku we Wrocławiu odbyła się Czwarta Polsko-Francuska Konferencja Pneumonologiczna [...]

Combined Pulmonary Fibrosis and Emphysema: Case Report and Literature Review

We describe the case of a 61-year-old male patient, in which the search for the cause of chronic respiratory failure, severe pulmonary hypertension and secondary erythrocytosis resulted in a diagnosis of combined pulmonary fibrosis and emphysema (CPFE). This is a unique, recently characterised syndrome with upper-lobe emphysema and pulmonary fibrosis of the lower lungs. The cause is unknown, but one of the main risk factor remains smoking. The patient was a heavy smoker (over 40 pack-years). He complained of dyspnoea on exertion and cough. Physical examination revealed basal crackles and cyanosis. The patient had severe reduction in diffusing capacity, out of proportion to his lung volumes (DLCO 27% of predicted value, FEV1 2.95 l (100%), FVC 4.41 l (118%), FEV1/FVC (66%). The blood gas showed hypoxemia (pO2 37 mm Hg), hypocapnia and respiratory alkalosis. Diagnosis was based on chest computer tomography, which revealed upper lobe emphysema and lower lobe ground glass changes and honeycombing. Severe pulmonary hypertension (SPAP 80 mm Hg) was confirmed by echocardiography and right cardiac catherisation. The patient received long-term oxygen therapy, inhaled corticosteroid and Ca-blocker.

[Combined pulmonary fibrosis and emphysema - case report and literature review]

We describe the case of a 61-year-old male patient, in which the search for the cause of chronic respiratory failure, severe pulmonary hypertension and secondary erythrocytosis resulted in a diagnosis of combined pulmonary fibrosis and emphysema (CPFE). This is a unique, recently characterised syndrome with upper-lobe emphysema and pulmonary fibrosis of the lower lungs. The cause is unknown, but one of the main risk factor remains smoking. The patient was a heavy smoker (over 40 pack-years). He complained of dyspnoea on exertion and cough. Physical examination revealed basal crackles and cyanosis. The patient had severe reduction in diffusing capacity, out of proportion to his lung volumes (DLCO 27% of predicted value, FEV1 2.95 l (100%), FVC 4.41 l (118%), FEV1/FVC (66%). The blood gas showed hypoxemia (pO2 37 mm Hg), hypocapnia and respiratory alkalosis. Diagnosis was based on chest computer tomography, which revealed upper lobe emphysema and lower lobe ground glass changes and honeycombing. Severe pulmonary hypertension (SPAP 80 mm Hg) was confirmed by echocardiography and right cardiac catherisation. The patient received long-term oxygen therapy, inhaled corticosteroid and Ca-blocker.

Role of hypercapnia in brain oxygenation in sleep-disordered breathing

Adaptive mechanisms may diminish the detrimental effects of recurrent nocturnal hypoxia in obstructive sleep apnea (OSA). The potential role of elevated carbon dioxide (CO2) in improving brain oxygenation in the patients with severe OSA syndrome is discussed. CO2 increases oxygen uptake by its influence on the regulation of alveolar ventilation and ventilation-perfusion matching, facilitates oxygen delivery to the tissues by changing the affinity of oxygen to hemoglobin, and increases cerebral blood flow by effects on arterial blood pressure and on cerebral vessels. Recent clinical studies show improved brain oxygenation when hypoxia is combined with hypercapnia. Anti-inflammatory and protective against organ injury properties of CO2 may also have therapeutic importance. These biological effects of hypercapnia may improve brain oxygenation under hypoxic conditions. This may be especially important in patients with severe OSA syndrome.

[Influence of nocturnal hypoxemia on the function of the visual tract in the course of the obstructive sleep apnea syndrome]

BACKGROUND AND PURPOSE

In patients with obstructive sleep apnea (OSA) syndrome the episodes of upper airway obstruction lead to hypoxemia during sleep. The aim of the study was to establish the influence of sleep hypoxemia on the function of the visual tract in OSA patients.

MATERIAL AND METHODS

The latency and amplitude of wave P100 of visual evoked potentials have been studied in 35 patients with OSA syndrome (mean apnea index 48+/-19). The diagnosis of OSA was established on the basis of continuous recordings of the respiratory function during sleep with additional full polysomnography in 17 patients.

RESULTS

Mean absolute latency of P100 was longer in OSA patients than in healthy controls (117.0+/-8.8 ms vs. 104.3+/-4.6 ms, p<0.001). The differences in the amplitude of P100 were not significant (5.9+/-2.6 mV in OSA patients and 7.62+/-3.04 mV in healthy persons). In 60% of patients the latency of P100 exceeded 118 ms; in this group of patients the mean SaO2 during sleep apneas was lower than in patients with normal P100 latency (46+/-15% vs. 69+/-10%, p<0.05). Full polysomnographic studies revealed that in patients with prolonged latencies as compared with patients with normal P100 latencies there were lower: minimal SaO2 during NREM sleep (63+/-12% vs. 78+/-8%, p<0.05), as well as mean and minimal SaO2 during REM sleep (53+/-15% vs. 80+/-5% and 46+/-15% vs. 69+/-10%, p<0.05), without differences in apnea index or apnea duration.

CONCLUSIONS

In patients with OSA syndrome the electrophysiological abnormalities suggesting damage of the optical tract may develop probably as a consequence of profound sleep hypoxemia.

Brain preconditioning and obstructive sleep apnea syndrome

Intermittent hypoxia stimulates the development of adaptive responses, called preconditioning. This process is partially mediated by genetic remodeling, via hypoxia inducible factor (HIF), which induces long-term adaptation processes and is responsible for the increase of levels of vascular endothelial growth factor (VEGF), erythropoietin (Epo), atrial natriuretic peptide (ANP), and nitric oxide (NO). The synthesis of brain-derived neurotrophic factor (BDNF) participates in the control of neural plasticity after hypoxia. The mechanisms of neuroprotection against hypoxia may be related to vascular adjustments and to central neurogenic neuroprotection. Some of the factors known to be involved in the development of the mechanism of neuroprotection are also present in the responses to repetitive apneas that occur during sleep in patients with obstructive sleep apnea (OSA) syndrome, who are frequently exposed to severe sleep hypoxemia. It appears that OSA syndrome represents a clinical example of preconditioning and the development of adaptive responses to intermittent hypoxia.

[Comparative evaluation of two health-related quality of life questionnaires in patients with sleep apnea]

Symptoms and complications of the obstructive sleep apnea (SAS) lead to a significant impairment of the health-related quality of life (HRQOL) of the affected individuals. Most HRQOL questionnaires have been published in English. Formal process of evaluation has to precede the introduction of a new language version of a HRQOL questionnaire. We conducted a comparative evaluation of the Polish versions of two HRQOL questionnaires: The Calgary Sleep Apnea Quality of Life Questionnaire (SAQLI) and The Functional Outcomes of Sleep Questionnaire (FOSQ). We examined the reliability, validity, stability and responsiveness of both questionnaires. Cronbach's alpha coefficient amounted to 0.94 for both questionnaires, which confirmed their reliability. Scores of both questionnaires highly correlated with measures of daily sleepiness, general health and SF-36 questionnaire scores. Both SAQLI and FOSQ gave stable results, but SAQLI was found to be more sensitive than FOSQ. The Polish version of FOSQ was proved to be a useful tool in cross-sectional assessment of HRQOL in patients with SAS. Stability and responsiveness of the Polish version of SAQLI and normal distribution of its scores make this questionnaire a preferable instrument in repeated assessments of HRQOL in the same group of patients.

[Obstructive sleep apnea syndrome as a risk factor of glaucomatous neuropathy]

The consequences of sleep apneas in patients with obstructive sleep apnea (OSA) syndrome may influence the function of visual system. In 21 patients with OSA syndrome (apnea/hypopnea index--AHI 50+/-20) the detailed ophthalmologic studies, including tonometry, biomicroscopic evaluation of the anterior segment of the eye, automatic perimetry and stereoscopic examination of the eye fundus have been performed. In 4 patients (19%) the signs of lesions in the optic tract have been found. These were: defects in visual field caused by glaucoma (primary open-angle glaucoma and normal-tension glaucoma) in 2 patients and defects in visual field (concentric and quadrantic homonymous) caused by diffuse lesions in the cortico-nuclear tract in 2 patients. In patients with the lesions in the optic tract there were severe disorders of breathing during sleep: AHI >60, mean SaO2 at the end of the apneas <86% and minimal SaO2 at the end of the apneas <70%. The authors conclude that in OSA patients there is a high risk of the lesions of the optic tract as a consequence of severe and repetitive hypoxemia during sleep.