Insulin Neuroprotection and the Mechanisms

Objective:

To analyze the mechanism of neuroprotection of insulin and which blood glucose range was benefit for insulin exerting neuroprotective action.

Data Sources:

The study is based on the data from PubMed.

Study Selection:

Articles were selected with the search terms “insulin”, “blood glucose”, “neuroprotection”, “brain”, “glycogen”, “cerebral ischemia”, “neuronal necrosis”, “glutamate”, “γ-aminobutyric acid”.

Results:

Insulin has neuroprotection. The mechanisms include the regulation of neurotransmitter, promoting glycogen synthesis, and inhibition of neuronal necrosis and apoptosis. Insulin could play its role in neuroprotection by avoiding hypoglycemia and hyperglycemia.

Conclusions:

Intermittent and long-term infusion insulin may be a benefit for patients with ischemic brain damage at blood glucose 6–9 mmol/L.     

Obstructive Sleep Apnea Syndrome is Associated with Metabolic Syndrome among Adolescents and Youth in Beijing: Data from Beijing Child and Adolescent Metabolic Syndrome Study

Background:

Obstructive sleep apnea (OSA) syndrome has a negative impact on the health of millions of adolescents and youth. The aim of this study was to evaluate the associations of OSA syndrome with obesity and cardiometabolic risk factors among adolescents and youth at risk for metabolic syndrome (MS).

Methods:

A total of 558 subjects aged 14–28 years were recruited from the Beijing Child and Adolescent Metabolic Syndrome Study. Each underwent a 2-h oral glucose tolerance test (OGTT), echocardiography, and liver ultrasonography. Anthropometric measures, blood levels of glucose, lipids, and liver enzymes were assessed. Subjects with high or low risk for OSA were identified by Berlin Questionnaire (BQ).

Results:

Among the subjects in obesity, 33.7% of whom were likely to have OSA by BQ. Subjects with high risk for OSA had higher neck and waist circumference and fat mass percentage compared to those with low risk for OSA (P < 0.001). Moreover, significant differences in levels of lipids, glucose after OGTT, and liver enzymes, as well as echocardiographic parameters were found between the two groups with high or low risk for OSA (P < 0.05). The rates of nonalcoholic fatty liver disease (71.0% vs. 24.2%), MS (38.9% vs. 7.0%), and its components in high-risk group were significantly higher than in low-risk group.

Conclusions:

The prevalence of OSA by BQ was high in obese adolescents and youth. A high risk for OSA indicates a high cardiometabolic risk. Mechanisms mediating the observed associations require further investigation.     

Prevalence,clinical characteristics,and predictors of obesity hypoventilation syndrome in a large sample of Saudi patients with obstructive sleep apnea

Objectives:

To assess the prevalence, clinical characteristics, and predictors of obesity hypoventilation syndrome (OHS) in a large sample of Saudi patients with obstructive sleep apnea (OSA).

Methods:

This prospective observational study consisted of 1693 patients who were diagnosed to have sleep-disordered breathing using type I attended polysomnography (PSG) between January 2002 and December 2012 in the University Sleep Disorders Center (USDC) at King Saud University Hospital, Riyadh, Kingdom of Saudi Arabia.

Results:

Out of 1693 OSA patients, OHS was identified in 144 (8.5%) (women 66.7%). Compared with the pure OSA patients, the OHS patients were significantly older (57.4±13.4 years versus 46.8±13.7 years), had a higher body mass index (44.6±10.8 versus 35.7±9.2 kg/m²), a higher daytime partial pressure of carbon dioxide (PaCO₂) (56.5±12.7 versus 41.6±6.7 mmHg), a longer duration of nocturnal oxygen saturation (nSaO₂) <90% (71.0±34.3 versus 10.5±20.5 minutes), and a higher apnea hypopnea index (68.2±47.1 versus 46.5±34.1 events/hour). A multivariate logistic regression analysis showed that serum bicarbonate (odds ratio [OR]=1.17, p=0.0001, confidence interval [CI]=1.10-1.25), and duration of nSaO₂ <90% (OR=1.05, p=0.0001, CI=1.04-1.06) were predictors of OHS.

Conclusion:

Obesity hypoventilation syndrome is common among Saudi OSA patients referred to the Sleep Disorders Center. Serum bicarbonate and duration of nSaO₂ <90% are independent predictors of OHS among patients with OSA.Sleep-related breathing disorders, also referred to as sleep-disordered breathing (SDB), are common conditions that encompass several disorders characterized by an abnormality in the frequency, pattern, upper airway resistance, and/or depth of breathing during sleep. Each disorder has its own diagnostic criteria. The most common SDB disorder is obstructive sleep apnea (OSA).1 The spectrum of SDB syndromes also includes obesity hypoventilation syndrome (OHS).2 Obesity hypoventilation syndrome was first described in 1955 as “Pickwickian syndrome.”3 Because most patients with OHS have frequent episodes of obstructive respiratory events during sleep and significant desaturation, OHS was incorrectly considered by some to be a severe form of OSA.2 The International Classification of Sleep Disorders, third edition (ICSD-3), defines OHS as the combined presence of obesity (BMI>30 kg/m²) with awake arterial hypercapnia (partial pressure of carbon dioxide (PaCO₂)>45 mmHg) and SDB in the absence of other causes of alveolar hypoventilation.4 The OHS is under recognized, with only approximately 30% of hospitalized patients receiving a correct diagnosis when admitted with acute-on-chronic hypercapnia respiratory failure.5,6 Because OHS patients have more progressive disease courses, higher health-care utilization, poorer prognoses, and higher risks of hospitalization and death compared with pure OSA patients,7,8 it is essential to study the clinical characteristics of this group of patients to aid general physicians in understanding and recognizing the disorder. Therefore, this study was conducted to assess the prevalence, clinical characteristics, and predictors of OHS in a large sample of Saudi OSA patients presenting to the Sleep Disorders Clinic with clinical suspicion of SDB.     

Audit of an urban paediatric emergency department visits

Background:

This study aimed to highlight the health seeking behavior of children in an Emergency Department (ED).

Materials and Methods:

Retrospective files review of ED was done for the month of July, 2008. Data about the children ≤12 years of age was gathered.

Results:

In one month period a total 21000 patients visited our ED, out of them 6120 (29%) were children. Males, Saudis and children of (1-6 years) were more frequent, i.e., 3540 (57.8%), 5760 (94.1%) and 3180 (52%), respectively. Majority of patients visited in shift “2”, i.e., 15:30 hours to 23:30 hours. Among the patients “diseases of respiratory system” were found more frequent 4170 (68.1%) and main diagnosis was “acute upper respiratory tract infection” 3300 (53.9%). Non-urgent cases were 2020 (33%) while 244 (4%) were admitted.

Conclusion:

Young children as well as non-urgent cases were predominant. Evening shift was the busiest one.     

Intestinal Microbiota Metabolism and Atherosclerosis

Objective:

This review aimed to summarize the relationship between intestinal microbiota metabolism and cardiovascular disease (CVD) and to propose a novel CVD therapeutic target.

Data Sources:

This study was based on data obtained from PubMed and EMBASE up to June 30, 2015. Articles were selected using the following search terms: “Intestinal microbiota”, “trimethylamine N-oxide (TMAO)”, “trimethylamine (TMA)”, “cardiovascular”, and “atherosclerosis”.

Study Selection:

Studies were eligible if they present information on intestinal microbiota metabolism and atherosclerosis. Studies on TMA-containing nutrients were also included.

Results:

A new CVD risk factor, TMAO, was recently identified. It has been observed that several TMA-containing compounds may be catabolized by specific intestinal microbiota, resulting in TMA release. TMA is subsequently converted to TMAO in the liver. Several preliminary studies have linked TMAO to CVD, particularly atherosclerosis; however, the details of this relationship remain unclear.

Conclusions:

Intestinal microbiota metabolism is associated with atherosclerosis and may represent a promising therapeutic target with respect to CVD management.     

A Nomogram for Predicting the Likelihood of Obstructive Sleep Apnea to Reduce the Unnecessary Polysomnography Examinations

Background:

The currently available polysomnography (PSG) equipments and operating personnel are facing increasing pressure, such situation may result in the problem that a large number of obstructive sleep apnea (OSA) patients cannot receive timely diagnosis and treatment, we sought to develop a nomogram quantifying the risk of OSA for a better decision of using PSG, based on the clinical syndromes and the demographic and anthropometric characteristics.

Methods:

The nomogram was constructed through an ordinal logistic regression procedure. Predictive accuracy and performance characteristics were assessed with the area under the curve (AUC) of the receiver operating characteristics and calibration plots, respectively. Decision curve analyses were applied to assess the net benefit of the nomogram.

Results:

Among the 401 patients, 73 (18.2%) were diagnosed and grouped as the none OSA (apnea-hypopnea index [AHI] <5), 67 (16.7%) the mild OSA (5 ≤ AHI < 15), 82 (20.4%) the moderate OSA (15 ≤ AHI < 30), and 179 (44.6%) the severe OSA (AHI ≥ 30). The multivariable analysis suggested the significant factors were duration of disease, smoking status, difficulty of falling asleep, lack of energy, and waist circumference. A nomogram was created for the prediction of OSA using these clinical parameters and was internally validated using bootstrapping method. The discrimination accuracies of the nomogram for any OSA, moderate-severe OSA, and severe OSA were 83.8%, 79.9%, and 80.5%, respectively, which indicated good calibration. Decision curve analysis showed that using nomogram could reduce the unnecessary polysomnography (PSG) by 10% without increasing the false negatives.

Conclusions:

The established clinical nomogram provides high accuracy in predicting the individual risk of OSA. This tool may help physicians better make decisions on PSG arrangement for the patients referred to sleep centers.     

Role of Oral Appliances in the Management of Sleep Disorders

Background

A study was undertaken with the aim to evaluate the therapeutic and clinical efficacy of oral appliances in the management of upper airway sleep disorders like snoring and obstructive sleep apnea (OSA).

Methods

Oral appliances were prescribed in eight cases of non - apneic snoring and 42 polysomnography (PSG) diagnosed cases of OSA. The cases were assessed on Epworth Sleepiness Scale (ESS) and Apnea - Hypopnea Index (AHI).

Result

62.5% of the non - apneic snoring cases reported gross reduction/cessation of snoring. In the OSA cases, the mean AHI and ESS scores decreased from 51.48 ± 23.70 to 32.78 ± 18.06 and 12.50 ± 3.57 to 7.20 ± 2.917 respectively. A statistically significant (p<0.0001) improvement in AHI and ESS scores was observed.

Conclusion

Short term therapeutic efficacy of oral appliances therapy in non-apneic snoring and OSA cases was observed.Key Words: Snoring, Obstructive sleep apnea, Oral appliances     

Current and Future Clinical Applications of Zinc Transporter-8 in Type 1 Diabetes Mellitus

Objective:

To evaluate the utility of zinc transporter-8 (ZnT8) in the improvement of type 1 diabetes mellitus (T1DM) diagnosis and prediction, and to explore whether ZnT8 is a potential therapeutic target in T1DM.

Data Sources:

A search was conducted within the medical database PubMed for relevant articles published from 2001 to 2015. The search terms are as follows: “ZnT8,” “type 1 diabetes,” “latent autoimmune diabetes in adults,” “type 2 diabetes,” “islet autoantibodies,” “zinc supplement,” “T cells,” “β cell,” “immune therapy.” We also searched the reference lists of selected articles.

Study Selection:

English-language original articles and critical reviews concerning ZnT8 and the clinical applications of islet autoantibodies in diabetes were reviewed.

Results:

The basic function of ZnT8 is maintaining intracellular zinc homeostasis, which modulates the process of insulin biosynthesis, storage, and secretion. Autoantibodies against ZnT8 (ZnT8A) and ZnT8-specific T cells are the reliable biomarkers for the identification, stratification, and characterization of T1DM. Additionally, the results from the animal models and clinical trials have shown that ZnT8 is a diabetogenic antigen, suggesting the possibility of ZnT8-specific immunotherapy as an alternative for T1DM therapy.

Conclusions:

ZnT8 is a novel islet autoantigen with a widely potential for clinical applications in T1DM. However, before the large-scale clinical applications, there are still many problems to be solved.     

Role of Quantitative Magnetic Resonance Imaging Parameters in the Evaluation of Treatment Response in Malignant Tumors

Objective:

To elaborate the role of quantitative magnetic resonance imaging (MRI) parameters in the evaluation of treatment response in malignant tumors.

Data Sources:

Data cited in this review were obtained mainly from PubMed in English from 1999 to 2014, with keywords “dynamic contrast-enhanced (DCE)-MRI,” “diffusion-weighted imaging (DWI),” “microcirculation,” “apparent diffusion coefficient (ADC),” “treatment response” and “oncology.”

Study Selection:

Articles regarding principles of DCE-MRI, principles of DWI, clinical applications as well as opportunity and aspiration were identified, retrieved and reviewed.

Results:

A significant correlation between ADC values and treatment response was reported in most DWI studies. Most quantitative DCE-MRI studies showed a significant correlation between K^trans values and treatment response. However, in different tumors and studies, both high and low pretreatment ADC or K^trans values were found to be associated with response rate. Both DCE-MRI and DWI demonstrated changes in their parameters hours to days after treatment, showing a decrease in K^trans or an increase in ADC associated with response in most cases.

Conclusions:

Combinations of quantitative MRI play an important role in the evaluation of treatment response of malignant tumors and hold promise for use as a cancer treatment response biomarker. However, validation is hampered by the lack of reproducibility and standardization. MRI acquisition protocols and quantitative image analysis approaches should be properly addressed prior to further testing the clinical use of quantitative MRI parameters in the assessment of treatments.     

Long-term compliance with continuous positive airway pressure in Saudi patients with obstructive sleep apnea: A prospective cohort study

Objectives:

To evaluate continuous positive airway pressure (CPAP) compliance and define predictors of CPAP compliance among Saudi patients with obstructive sleep apnea (OSA) after applying an educational program.

Methods:

This prospective cohort study included consecutive patients diagnosed to have OSA based on polysomnography between January 2012 and January 2014 in King Saud University, Riyadh, Kingdom of Saudi Arabia. All patients had educational sessions on OSA and CPAP therapy before sleep study, and formal hands-on training on CPAP machines on day one, day 7, and day 14 after diagnosis. The follow-up in the clinic was carried out at one, 4, and 10 months after initiating CPAP therapy. Continuous positive airway pressure compliance was assessed objectively. Logistic regression model was used to assess the predictors of CPAP adherence.

Results:

The study comprised 156 patients with a mean age of 51.9±12.1 years, body mass index of 38.4±10.6 kg/m², and apnea hypopnea index of 63.7±39.3 events/hour. All patients were using CPAP at month one, 89.7% at month 4, and 83% at month 10. The persistence of CPAP-related side effects and comorbid bronchial asthma remained as independent predictors of CPAP compliance at the end of the study.

Conclusion:

With intensive education, support, and close monitoring, more than 80% of Saudi patients with OSA continued to use CPAP after 10 months of initiating CPAP therapy.Continuous positive airway pressure (CPAP) is a standard, safe, and efficacious treatment for obstructive sleep apnea (OSA), a common disorder with established harm to quality of life and adverse consequences for cardiovascular health.1 Obstructive sleep apnea is characterized by recurrent partial (hypopnea) or complete (apnea) upper airway obstruction during sleep. These recurrent respiratory events usually cause intermittent hypoxemia and sleep fragmentation.2 Recent data demonstrated that the estimated prevalence of moderate to severe OSA ranges from 10-17% in middle-aged and elderly men.3 In Saudi Arabia, 3 out of 10 middle-aged Saudi men and 4 out of 10 middle-aged Saudi women are at high risk of having OSA.4,5 The mainstay medical treatment for OSA is CPAP therapy.6 Among various available therapeutic modalities for OSA, CPAP remains the most effective treatment.6 Continuous positive airway pressure is a machine that applies positive airway pressure to the upper air passages via a mask fitted on the mouth or nose to keep the throat open.6 Previous studies in Western countries showed that OSA patients on CPAP therapy use their machines on average from 4.5 to 5.5 hours per night with compliance rates ranging from 30-85%.7,8 Several studies have been conducted to define factors that influence, or predict CPAP use and adherence, and reported conflicting results.6 Moreover, several studies reported that race might influence CPAP adherence. For example, available data suggest lower CPAP adherence among African Americans than Caucasians.9 An earlier study that assessed CPAP compliance subjectively (self-reports) among Saudi patients with OSA after 3 months of initiation of CPAP therapy revealed an overall compliance rate of 39%.10 However, self-reports have been shown to overestimate CPAP use by approximately one hour/night when compared with objectively measured CPAP use.11 In general, there are very few data on objectively assessed long-term CPAP compliance in the literature. Moreover, there is a lack of previous study objectively addressing the rate of CPAP compliance, the predictors of good compliance, and the side effects of CPAP treatment in Saudi OSA patients. Therefore, we established in our center an educational program for patients with OSA and easily accessible medical support, and close follow-up of CPAP compliance. This study was conducted to evaluate CPAP compliance and to define predictors of CPAP compliance among Saudi patients with OSA after applying the new educational program.     

Role of MicroRNAs in Malignant Glioma

Objective:

This overview seeked to bring together the microRNA (miRNA) researches on biogenesis and bio-function in these areas of clinical diagnosis and therapy for malignant glioma.

Data Sources:

Using the keyword terms “glioma” and “miRNA,” we performed the literature search in PubMed, Ovid, and web.metstr.com databases from their inception to October 2014.

Study Selection:

In screening out the quality of the articles, factors such as clinical setting of the study, the size of clinical samples were taken into consideration. Animal studied for verification and reviews article were also included in our data collection.

Results:

Despite many advance in miRNA for malignant glioma, further studies were still required to focus on the following aspects: (i) Improving the understanding about biogenesis of miRNA and up-down regulation; (ii) utilizing high-throughput miRNA expression analysis to screen out the core miRNA for glioma; (iii) Focusing related miRNAs on the signal transduction pathways that regulate the proliferation and growth of glioma.

Conclusions:

We discussed the most promising miRNA, correlative signaling pathway and their relation with gliomas in the way of prompting miRNA target into being a clinical therapeutic strategy.     

J Wave Syndromes: A Decade of Progress

Objective:

The objective was to provide a brief history of J wave syndromes and to summarize our current understanding of their molecular, ionic, cellular mechanisms, and clinical features. We will also discuss the existing debates and further direction in basic and clinical research for J wave syndromes.

Data Sources:

The publications on key words of “J wave syndromes”, “early repolarization syndrome (ERS)”, “Brugada syndrome (BrS)” and “ST-segment elevation myocardial infarction (STEMI)” were comprehensively reviewed through search of the PubMed literatures without restriction on the publication date.

Study Selection:

Original articles, reviews and other literatures concerning J wave syndromes, ERS, BrS and STEMI were selected.

Results:

J wave syndromes were firstly defined by Yan et al. in a Chinese journal a decade ago, which represent a spectrum of variable phenotypes characterized by appearance of prominent electrocardiographic J wave including ERS, BrS and ventricular fibrillation (VF) associated with hypothermia and acute STEMI. J wave syndromes can be inherited or acquired and are mechanistically linked to amplification of the transient outward current (I_to)-mediated J waves that can lead to phase 2 reentry capable of initiating VF.

Conclusions:

J wave syndromes are a group of newly highlighted clinical entities that share similar molecular, ionic and cellular mechanism and marked by amplified J wave on the electrocardiogram and a risk of VF. The clinical challenge ahead is to identify the patients with J wave syndromes who are at risk for sudden cardiac death and determine the alternative therapeutic strategies to reduce mortality.     

Effects of Immunosuppressants on Immune Response to Vaccine in Inflammatory Bowel Disease

Objective:

To evaluate the response rate to vaccination in different treatment groups (nonimmunosuppressants and immunosuppressants).

Data Sources:

We completed an online systematic search using PubMed to identify all articles published in English between January 1990 and December 2013 assessing the effect of the response rate to vaccination in different treatment groups (with and without immunomodulators). The following terms were used: “inflammatory bowel disease (IBD)” OR “Crohn''s disease” OR “ulcerative colitis” AND (“vaccination” OR “vaccine”) AND (“corticosteroids” OR “mercaptopurine” OR “azathioprine” OR “methotrexate [MTX]”) AND “immunomodulators.”

Study Selection:

The inclusion criteria of articles were that the studies: (1) Randomized controlled trials which included patients with a diagnosis of IBD (established by standard clinical, radiographic, endoscopic, and histologic criteria); (2) exposed patients received immunomodulators for maintenance (weight-appropriate doses of 6-mercaptopurine/azathioprine or within 3 months of stopping, 15 mg or more MTX per week or within 3 months of stopping; (3) exposed patients received nonimmunomodulators (no therapy, antibiotics only, mesalazine only, biological agent only such as infliximab, adalimumab, certolizumab or natalizumab or within 3 months of stopping one of these agents). The exclusion criteria of articles were that the studies: (1) History of hepatitis B virus (HBV), influenza or streptococcus pneumoniae infection; (2) patients who had previously been vaccinated against HBV, influenza or streptococcus pneumoniae; (3) any medical condition known to cause immunosuppression (e.g. chronic renal failure and human immunodeficiency virus infection); (4) individuals with positive hepatitis markers or liver cirrhosis; (5) patients with a known allergy to eggs or other components of the vaccines and (6) pregnancy.

Results:

Patients treated with immunomodulators were associated with lower response rates to vaccination.

Conclusions:

Immunomodulators may impair the immune response to vaccination in patients with IBD. Vaccination should be made at the time of diagnosis or before starting immunosuppressed therapy.     

Prevalence and predictors of obstructive sleep apnea syndrome in a sample of patients with type 2 Diabetes Mellitus in Nigeria

Introduction:

Obstructive sleep apnea (OSA) and Diabetes Mellitus (DM) are growing health challenges worldwide. However, the relation of OSA with type 2 diabetes is not well understood in developing countries. This study described the prevalence and predictors of OSA in type 2 DM patients using a screening questionnaire.

Materials and Methods:

Patients aged 40years and above with type 2 diabetes mellitus were recruited into the study consecutively from the outpatient clinics of a university hospital. They were all administered the Berlin questionnaire and the Epworth sleepiness scale (ESS) to assess the risk of OSA and the tendency to doze off, respectively. Anthropometric details like height, weight and body mass index (BMI) were measured and short-term glycaemic control was determined using fasting blood glucose.

Results:

A total of 117 patients with type 2 diabetes mellitus were recruited into the study. The mean (SD) age, height and BMI was 63 years (11), 160 cm (9) and 27.5 kg/ m² (5.7), respectively. Twenty-seven percent of the respondents had a high risk for OSA and 22% had excessive daytime sleepiness denoted by ESS score above 10. In addition, the regression model showed that for every 1 cm increase in neck circumference, there is a 56% independent increase in the likelihood of high risk of OSA after adjusting for age, sex, BMI, waist, hip circumferences and blood glucose.

Conclusion:

Our study shows a substantial proportion of patients with type 2 diabetes may have OSA, the key predictor being neck circumference after controlling for obesity.     

Altered Wnt Signaling Pathway in Cognitive Impairment Caused by Chronic Intermittent Hypoxia: Focus on Glycogen Synthase Kinase-3β and β-catenin

Background:

Cognitive impairment is a severe complication caused by obstructive sleep apnea (OSA). The mechanisms of causation are still unclear. The Wnt/β-catenin signaling pathway is involved in cognition, and abnormalities in it are implicated in neurological disorders. Here, we explored the Wnt/β-catenin signaling pathway abnormalities caused by chronic intermittent hypoxia (CIH), the most characteristic pathophysiological component of OSA.

Methods:

We divided 32 4-week-old male C57/BL mice into four groups of eight each: a CIH + normal saline (NS) group, CIH + LiCl group, sham CIH + NS group, and a sham CIH + LiCl group. The spatial learning performance of each group was assessed by using the Morris water maze (MWM). Protein expressions of glycogen synthase kinase-3β (GSK-3β) and β-catenin in the hippocampus were examined using the Western blotting test. EdU labeling and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining methods were used, respectively, to determine the proliferation and apoptosis of neurons in the hippocampal dentate gyrus region.

Results:

Mice exposed to CIH showed impaired spatial learning performance in the MWM, including increased mean escape latencies to reach the target platform, decreased mean times passing through the target platform and mean duration in the target quadrant. The GSK-3β activity increased, and expression of β-catenin decreased significantly in the hippocampus of the CIH-exposed mice. Besides, CIH significantly increased hippocampal neuronal apoptosis, with an elevated apoptosis index. Meanwhile, LiCl decreased the activity of GSK-3β and increased the expression of β-catenin and partially reversed the spatial memory deficits in MWM and the apoptosis caused by CIH.

Conclusions:

Wnt/β-catenin signaling pathway abnormalities possibly play an important role in the development of cognitive deficits among mice exposed to CIH and that LiCl might attenuate CIH-induced cognitive impairment via Wnt/β-catenin signaling pathway.     

Prevalence and risks of habitual snoring and obstructive sleep apnea symptoms in adult dental patients

Objectives:

To determine the prevalence of habitual snoring and risk of obstructive sleep apnea (OSA) among dental patients and investigate factors associated with high-risk OSA.

Methods:

This cross-sectional study was performed at the Department of Preventive Dental Sciences, College of Dentistry, University of Dammam, Kingdom of Saudi Arabia, between October and December 2014. A total of 200 consecutive female and male dental patients were included in this study. Subjective and objective assessments were carried out. Habitual snoring and risk of OSA were assessed using the Arabic version of the Berlin questionnaire. Two trained investigators carried out the objective measurements of anthropometric data, blood pressure, oxygen saturation, pulse rate, and clinical examination of upper-airway, and dental occlusion.

Results:

Habitual snoring was present in 18.2% of the females and 81.8% of the males (p<0.05). Breathing pauses during sleep of more than once a week occurred in 9% (n=17) of the sample. Of the males, 78.3% were at high risk of OSA compared with 21.7% of the females. Multivariate analysis for risk of OSA revealed that obese patients were almost 10 times more likely to report OSA symptoms than their non-obese counterparts (odds ratio: 9.9, 95% confidence intervals: 4.4-22.1). Tongue indentations, tonsil size, and a high Epworth Sleepiness Scale score were also independent risks of OSA.

Conclusion:

Tongue indentations and tonsil grades III and IV were significantly associated with risk of OSA. This validates the important role of dentists in the recognition of the signs and symptoms of OSA.Obstructive sleep apnea (OSA) is a repetitive complete or partial obstruction of the upper airway during sleep.1 It is characterized by snoring, hypoxia, hypercapnia, and arousals from sleep.2 Obstructive sleep apnea is found in 24% of male and 9% of female adults.3 Data from the Canadian Community Health Survey4 showed that approximately 26% of adult Canadians were at high risk of developing OSA. Two studies5,6 in Saudi Arabian population reported a 39% prevalence of OSA in females and 33.3% in males. Obstructive sleep apnea can cause tiredness, anxiety, depression, and is associated with diminished motor and cognitive functions, and reduced quality of life.7 The individuals with OSA have 2-10 times increased risk of motor vehicle accidents than those without OSA.8 Untreated OSA has been linked to systemic complications such as coronary artery disease,9 heart failure,2 impaired glucose tolerance, insulin resistance, and dyslipidemia10 among other conditions. Unfortunately, most of the OSA cases (85%) remain undiagnosed,11 partly due to lack of information to patients and health professionals as well as the high costs of diagnostic tests. Several factors contribute to the development of OSA, which includes obesity, older age,12 male gender, menopause, hereditary, smoking, alcohol, craniofacial abnormalities,13 and periodontal disease.14 Orofacial anatomical abnormalities such as mandibular micrognathia or retrognathia, large tongue, hypertrophy of palatine tonsils, enlarged uvula, and deep palatal arch are craniofacial risks for developing OSA.15 Habitual snoring is one of the symptoms of sleep disordered breathing. A population based longitudinal study found that 13% of adults developed habitual snoring over 14 years. The factors associated with habitual snoring include male gender, obesity, smoking, and asthma.16 In addition, snoring is strongly associated with increased all-cause mortality.17 Dentists play a major role in the recognition of the signs and symptoms and the overall management of OSA.18 No data exist on the epidemiology or risks of OSA symptoms among dental patients in Saudi Arabia. This study aims to determine the prevalence of habitual snoring and OSA risk in adult dental patients and investigate the factors associated with high risk of OSA.     

Frequency-specific Alterations of Large-scale Functional Brain Networks in Patients with Alzheimer's Disease

Background:

Previous studies have indicated that the cognitive deficits in patients with Alzheimer''s disease (AD) may be due to topological deteriorations of the brain network. However, whether the selection of a specific frequency band could impact the topological properties is still not clear. Our hypothesis is that the topological properties of AD patients are also frequency-specific.

Methods:

Resting state functional magnetic resonance imaging data from 10 right-handed moderate AD patients (mean age: 64.3 years; mean mini mental state examination [MMSE]: 18.0) and 10 age and gender-matched healthy controls (mean age: 63.6 years; mean MMSE: 28.2) were enrolled in this study. The global efficiency, the clustering coefficient (CC), the characteristic path length (CpL), and “small-world” property were calculated in a wide range of thresholds and averaged within each group, at three different frequency bands (0.01–0.06 Hz, 0.06–0.11 Hz, and 0.11–0.25 Hz).

Results:

At lower-frequency bands (0.01–0.06 Hz, 0.06–0.11 Hz), the global efficiency, the CC and the “small-world” properties of AD patients decreased compared to controls. While at higher-frequency bands (0.11–0.25 Hz), the CpL was much longer, and the “small-world” property was disrupted in AD, particularly at a higher threshold. The topological properties changed with different frequency bands, suggesting the existence of disrupted global and local functional organization associated with AD.

Conclusions:

This study demonstrates that the topological alterations of large-scale functional brain networks in AD patients are frequency dependent, thus providing fundamental support for optimal frequency selection in future related research.     

Creation of a corpus for evidence based medicine summarisation

Background

Automated text summarisers that find the best clinical evidence reported in collections of medical literature are of potential benefit for the practice of Evidence Based Medicine (EBM). Research and development of text summarisers for EBM, however, is impeded by the lack of corpora to train and test such systems.

Aims

To produce a corpus for research in EBM summarisation.

Method

We sourced the “Clinical Inquiries” section of the Journal of Family Practice (JFP) and obtained a sizeable sample of questions and evidence based summaries. We further processed the summaries by combining automated techniques, human annotations, and crowdsourcing techniques to identify the PubMed IDs of the references.

Results

The corpus has 456 questions, 1,396 answer components, 3,036 answer justifications, and 2,908 references.

Conclusion

The corpus is now available for the research community at http://sourceforge.net/projects/ebmsumcorpus.     

Contemporary approaches to managing atrial fibrillation: A survey of Australian general practitioners

Background

Recent attention to the management of atrial fibrillation (AF) and stroke prevention has emphasised the need to support the use of existing pharmacotherapy through available services and resources, in preference to using the new, more expensive, novel oral anticoagulants. In this regard, general practitioners (GPs) are at the core of care.

Aims

To survey Australian GPs regarding their approach to managing AF, particularly in relation to stroke prevention therapy, and to identify the range of services to support patient care.

Methods

A structured questionnaire, comprising quantitative and qualitative responses, was administered to participating GPs within four geographical regions of NSW (metropolitan, regional, rural areas).

Results

Fifty GPs (mean age 53.74±9.94 years) participated. Most (98 per cent) GPs regarded themselves as primarily responsible for the management of AF, only referring patients to specialists when needed. However, only 10 per cent of GPs specialised in “heart/vascular health”. Most (76 per cent) GPs offered point-of-care international normalised ratio (INR) testing, with 90 per cent also offering patient support via practice nurses and home visits. Overall, key determinants influencing GPs’ initiation of antithrombotic therapy were: “stroke risk”/”CHADS₂ score”, followed by “patients’ adherence/compliance”. GPs focused more on medication safety considerations and the day-to-day management of therapy than on the risk of bleeding.

Conclusion

Australian GPs are actively engaged in managing AF, and appear to be well resourced. Importantly, there is a greater focus on the benefits of therapy during decision-making, rather than on the risks. However, medication safety considerations affecting routine management of therapy remain key concerns, with patients’ adherence to therapy a major determinant in decision-making.