Diabetes and sleep disturbances: findings from the Sleep Heart Health Study

Reduced systemic levels of IL-10 are associated with the severity of obstructive sleep apnea and insulin resistance in morbidly obese humans

Obstructive sleep apnea (OSA) has been related to elevation of inflammatory cytokines and development of insulin resistance in morbidly obese (MO) subjects. However, it is still unclear whether the systemic concentration of anti-inflammatory mediators is also affected in MO subjects directly related to the severity of OSA and level of insulin resistance. Normal weight and MO subjects were subjected to overnight polysomnography in order to establish the severity of OSA, according to the apnea-hypopnea index (AHI). Blood samples were obtained for estimation of total cholesterol and triglycerides, insulin, glucose, insulin resistance, tumor necrosis factor alpha (TNF-α), interleukin 12 (IL12), and interleukin 10 (IL-10). Serum levels of IL-10 were significantly lower in MO subjects with OSA than in MO and control individuals without OSA. Besides being inversely associated with serum TNF-α and IL-12, decreased IL-10 levels were significantly related to increased AHI, hyperinsulinemia, and insulin resistance. Serum IL-10 is significantly reduced in morbidly obese subjects with severe OSA while also showing a clear relationship with a state of hyperinsulinemia and insulin resistance probably regardless of obesity in the present sample. It may be of potential clinical interest to identify the stimulatory mechanisms of IL-10 in obese individuals with OSA.

Sleep pattern in Charcot-Marie-Tooth disease type 2: report of family case series

OBJECTIVES

Charcot-Marie-Tooth (CMT) disease is the most prevalent hereditary motor and sensory polyneuropathy, and a condition in which sleep has rarely been studied, particularly in relation to the type 2 (CMT2). Thus, we aimed to characterize the sleep patterns of a family affected by CMT2 disease.

METHODS

Sixteen volunteers with CMT2 from the same multigenerational family agreed to participate in the study (refusal rate = 31%). All participants answered sleep questionnaires and came to the sleep laboratory to perform a diagnostic polysomnography (PSG). Clinical manifestation and severity of the disease were also evaluated.

RESULTS

56% of the sample were male and 44% female, with a mean age of 32 ± 17 years, of normal weight (body mass index 21 ± 3 kg/m(2)); 64% presented moderate to severe CMT2. Regarding subjective sleep, 31% had excessive daytime sleepiness and 75% reported poor sleep quality. The PSG results revealed that CMT2 patients had an increase in stage N3 and a reduction in REM sleep, in addition to a high arousal index. Although 81% of the sample were snorers, only 13% had an apnea-hypopnea index (AHI) > 5. However, a positive correlation was found between the severity of disease and the AHI.

CONCLUSIONS

Taken together, these data show that CMT2 disease is characterized by important changes in sleep architecture, probably due to sleep fragmentation. Although these alterations may worsen with disease severity, it seems that they are not related to sleep breathing or movement disorders.

Characterization of sleep breathing pattern in patients with type 2 diabetes: sweet sleep study

BACKGROUND

Although sleep apnea-hypopnea syndrome (SAHS) is highly prevalent in patients with type 2 diabetes (T2D), it is unknown whether or not subjects with and without T2D share the same sleep breathing pattern.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional study in patients with SAHS according to the presence (n = 132) or not (n = 264) of T2D. Both groups were matched by age, gender, BMI, and waist and neck circumferences. A subgroup of 125 subjects was also matched by AHI. The exclusion criteria included chronic respiratory disease, alcohol abuse, use of sedatives, and heart failure. A higher apnea hypopnea index (AHI) was observed in T2D patients [32.2 (10.2-114.0) vs. 25.6 (10.2-123.4) events/hours; p = 0.002). When sleep events were evaluated separately, patients with T2D showed a significant increase in apnea events [8.4 (0.1-87.7) vs. 6.3 (0.0-105.6) e/h; p = 0.044), as well as a two-fold increase in the percentage of time spent with oxygen saturation <90% [15.7 (0.0-97.0) vs. 7.9 (0.0-95.6) %; <0.001)], higher rates of oxygen desaturation events, and also higher daily sleepiness [7.0 (0.0-21.0) vs. 5.0 (0.0-21.0); p = 0.006)] than subjects without T2D. Significant positive correlations between fasting plasma glucose and AHI, the apnea events, and CT90 were observed. Finally, multiple linear regression analyses showed that T2D was independently associated with AHI (R2 = 0.217), the apnea index (R2 = 0.194), CT90 (R2 = 0.222), and desaturation events.

CONCLUSIONS/SIGNIFICANCE

T2D patients present a different pattern of sleep breathing than subject without diabetes. The most important differences are the severity of hypoxemia and the number of apneas whereas the incidence of hypopnea episodes is similar.

Obstructive sleep apnea and diabetes mellitus

BACKGROUND

There is convincing evidence that obstructive sleep apnea (OSA) is highly associated with impaired glucose metabolism.

OBJECTIVES

Analyze the prevalence of OSA in type 1 and type 2 diabetes mellitus (DM) patients. Evaluate the influence of OSA on glycemic control.

METHODS

The adult patients with diabetes mellitus (DM) followed in the department of internal medicine were referred to our Sleep Unit. A home respiratory polygraphy was then performed on all patients with body mass index (BMI) <40 kg/m(2). The glycemic control was assessed by the value of glycated hemoglobin (Hba1c) in the previous 3 months.

RESULTS

A total of 46 patients were studied (20 men and 26 women), the mean age was 50±15 years and mean BMI was 28.6±4.9 kg/m(2). The mean Hba1c was 8.3±1.2. Twenty three patients had type 2 DM and 23 patients had type 1 DM. Twenty nine patients (63.0%) had OSA and 8.7% had severe OSA (AHI>30/h). The mean CT90 was 5.3±12.5 and the mean AHI was 13.6±18.3. The mean AHI was similar between type 1 and type 2 DM (15.7±24.5 Vs 11.6±8.9; p=0.46). The AHI was not correlated with the BMI. Type 2 DM patients with poor glycemic control (HbA1c>7.5%) had a significantly higher mean AHI (14.3±9.0 vs 6.4±6.2; p=0.038). This difference did not remain significant after adjustment for BMI (p=0.151).

CONCLUSIONS

The prevalence of OSA in type 1 DM is similar to that found in type 2 DM. We note the high prevalence of OSA in younger patients with type 1 DM.

Comorbidity of diabetes and obstructive sleep apnea in hospitalized patients

Obstructive sleep apnea (OSA) and type 2 diabetes are two morbidities commonly encountered in the hospitalized setting. Both diseases will present with an array of complications if not managed in a timely, competent manner. However, a growing body of evidence suggests a link between these two pathologies. It is our hope that through careful review of the literature, we may generate heightened awareness of the OSA/diabetes comorbidity. Through better understanding of these conditions and their interactions, we may insure efficient management in the clinical setting and prevent exacerbation of common complications.

Effect of glycemic control on nocturnal arterial oxygen saturation: a case-control study in type 2 diabetic patients

BACKGROUND

There is growing evidence suggesting a deleterious effect of type 2 diabetes on lung function and sleep breathing. The aim of this case-control study was to evaluate whether or not an improvement in glycemic control could arrest or ameliorate nocturnal hypoxemia in type 2 diabetes.

METHODS

Thirty patients with type 2 diabetes with HbA1c ≥8% (cases) and 10 non-diabetic subjects were analyzed. Controls were closely matched to cases by age, gender, body mass index, and neck circumference. The nocturnal oxygen desaturation index (ODI) was calculated at baseline and 5 days after blood glucose improvement with pharmacological intervention. Four different oxygen desaturation thresholds (reductions in SaO2  ≥ 3%, 4%, 6%, and 8%) as indicators of hypoxemia severity (ODI-3%, ODI-4%, ODI-6%, ODI-8%) were used.

RESULTS

At baseline, patients with diabetes showed a higher number of ODI-3%, ODI-4%, and ODI-6% in comparison with controls. A significant reduction in ODI-3% (29.7 [4.8-107.9] events per hour at baseline versus 24.6 [3.1-97.7] e/h at discharge, P < 0.001), ODI-4% (21.7 [1.6-79.3] versus 14.7 [0.3- 79.4], P = 0.003), ODI-6% (9.3 [0.3-71.8] versus 4.0 [0.0-73.7], P = 0.001), and ODI-8% (4.1 [0.0-64.3] versus 1.1 [0.0-69.8], P = 0.033) was observed in patients with diabetes after 5 days of follow-up. However, no changes in ODI events were observed in non-diabetic patients after the same period. No significant changes in weight were observed in either group.

CONCLUSIONS

Glycemic control improvement significantly reduces the increased number of nocturnal oxygen desaturations that exist in type 2 diabetes. Although the mechanisms are not yet fully understood, the rapid effect without changes in body weight suggests a central mechanism involving respiratory center output.

Obstructive sleep apnea as a risk factor for type 2 diabetes mellitus

Obstructive sleep apnea (OSA) is independently associated with cardiovascular and cardiometabolic risk in several large epidemiologic studies. OSA leads to several physiologic disturbances such as intermittent hypoxia, sleep fragmentation, and increase in autonomic tone. These disturbances have been associated with insulin resistance and type 2 diabetes mellitus (T2DM) in animal and human studies. Studies also suggest a bidirectional relationship between OSA and T2DM whereby T2DM itself might contribute to the features of OSA. Moreover, successful treatment of OSA may reduce these risks, although this is controversial. The purpose of this article is to review 1) the links and bidirectional associations between OSA and T2DM; 2) the pathogenic mechanisms that might link these two disease states; 3) the role of continuous positive airway pressure therapy in improving glucose tolerance, sensitivity, and resistance; and 4) the implications for clinical practice.

Sleep respiratory disorders and clinical profile in patients with type 2 diabetes mellitus

Introduction Sleep respiratory disorders (SRDs) are often found in patients with type 2 diabetes mellitus (T2DM). Objective The aim was to establish the prevalence of risk to develop an SRD using the Clinical Berlin Questionnaire (CBQ) and Epworth Sleepiness Scale (ESS) in patients with T2DM and verifying the correlation of anthropometric measurements and life quality (LQ) with ESS. Methods A descriptive and analytical study of a case series evaluating 208 patients with T2DM, submitted to clinical and biochemical evaluation and implementation of CBQ, ESS, and WHOQOL-bref to evaluate LQ. Results Mean age was 60.8 ± 8.8 years, and 65.4% were women. Most diabetics were overweight (36.1%), and 29.8% were class I obese. One-third had positive risk signals for a SRD, with 87.0 and 34.1% having high risk in CBQ and sleep disorders in ESS, respectively. There was a significant difference in the general LQ between the low- and high-risk groups in the CBQ. Conclusion In this scenario, it is noteworthy that the active search for sleep disorders must start from simple methods, such as application of protocols.

Sleep, health-related quality of life, and functional outcomes in adults with diabetes

PURPOSE

This study explored the association of sleep quality with physical and mental health-related quality of life (HRQoL) and functional outcomes in 116 participants with type 2 diabetes.

METHODS

The study is a secondary analysis of baseline data from a clinical trial that examined treatment of obstructive sleep apnea on physical activity and glucose control. Instruments included the Pittsburgh Sleep Quality Index, Medical Outcomes Short-Form Physical Component and Mental Component Scores, and Functional Outcomes of Sleep Questionnaire.

RESULTS

Higher physical HRQoL was significantly associated with better sleep quality and improved functional outcomes of increased activity and productivity. Higher mental HRQoL was associated with improved sleep quality and improved functional outcomes of increased activity, social interactions, vigilance, and productivity. Poor sleep quality was a predictor of decreased functional outcomes while controlling for age, race, education, BMI, marital status and physical and mental HRQoL.

CONCLUSION

Poor sleep quality is associated with negative physical, mental, and functional outcomes in adults with type 2 diabetes.

At least one in three people with Type 2 diabetes mellitus referred to a diabetes centre has symptomatic obstructive sleep apnoea

AIMS

To investigate the prevalence of symptomatic obstructive sleep apnoea in unselected patients with Type 2 diabetes referred to a tertiary diabetes clinic.

METHODS

In a cross-sectional design, all newly referred patients were offered a stepwise screening for obstructive sleep apnoea with: (1) The Berlin questionnaire; then, if indicative: (2) overnight home monitoring with the ApneaLink™ device. Patients with an apnoea-hypopnoea index ≥ 5/h were offered referral for diagnostic polygraphy and treatment initiation.

RESULTS

A total of 200 patients participated (61% men; age 59.6 ± 10.5 years, diabetes duration 8.3 ± 6.3 years and BMI 31.7 ± 6.7 kg/m²). According to the questionnaire, 106 patients showed 'high risk' of obstructive sleep apnoea, and 72 of these were referred to polygraphy based on ApneaLink screening corresponding to a prevalence of symptomatic obstructive sleep apnoea of 39%. Patients with symptomatic obstructive sleep apnoea had significantly higher BMI, poorer glycaemic control and lower plasma HDL cholesterol levels as compared with patients unlikely to have obstructive sleep apnoea. The groups were not different with respect to sex, age, diabetes duration, blood pressure, diabetic complications or medication use. In multiple regression analyses, age, BMI and HDL cholesterol levels were all significant, independent predictors of obstructive sleep apnoea.

CONCLUSIONS

At least one third of people with Type 2 diabetes referred to a diabetes clinic in Denmark has symptomatic obstructive sleep apnoea. Our data suggest higher age, a compromised plasma lipid profile and a more obese phenotype in patients with Type 2 diabetes who have obstructive sleep apnoea, highlighting the need to focus on screening and treatment of obstructive sleep apnoea in these patients.

Obstructive sleep apnea and type 2 diabetes in older adults

Both obstructive sleep apnea (OSA) and type 2 diabetes mellitus are commonly seen in older adults. Over the last decade, there has been increasing recognition that OSA is highly prevalent in persons with type 2 diabetes and related metabolic conditions such as insulin resistance and glucose intolerance. Intermittent hypoxemia and recurrent arousals in OSA trigger a repertoire of pathophysiological events, which can in turn alter glucose homeostasis and possibly increase the risk for type 2 diabetes. Conversely, there is evidence that type 2 diabetes may alter the progression and expression of sleep-disordered breathing.

Effect of obstructive respiratory events on blood pressure and renal perfusion in a pig model for sleep apnea

BACKGROUND

Obstructive sleep apnea (OSA) is associated with hypertension and the progression of chronic kidney disease (CKD). Renal sympathetic innervation contributes to either condition.

METHODS

We investigated the effect of renal sympathetic denervation (RDN) on blood pressure (BP), renal perfusion, and neurohumoral responses during and after repetitive obstructive apneas in a pig model for OSA. BP, femoral artery, and renal artery flow were measured in 29 spontaneously breathing urethane-chloralose-anesthetized pigs. The effect of RDN (n = 14) and irbesartan (n = 3) was investigated. Repetitive tracheal occlusions for 2 minutes with applied negative tracheal pressure at -80 mbar were performed over 4 hours.

RESULTS

Spontaneous breathing attempts during tracheal occlusion caused an intra-apneic breathing synchronous oscillating pattern of renal flow. Renal flow oscillations were > 2-fold higher compared with femoral flow that almost showed changes proportional to the BP alterations (2.9%/mm Hg vs. 1.3%/mm Hg; P < 0.0001). A marked postapneic BP rise from 102 ± 3 to 172 ± 8 mm Hg (P < 0.00001) was associated with renal hypoperfusion (from 190 ± 24 to 70 ± 20 ml/min; P < 0.00001) occurring after application of obstructive respiratory events. RDN, but not irbesartan, inhibited postapneic BP rises and renal hypoperfusion and attenuated increased plasma renin activity and aldosterone concentration induced by repetitive tracheal occlusions. Additionally, increased urinary protein/creatinine ratio was significantly reduced by RDN, whereas intra-apneic hemodynamic changes or blood gases were not modified by RDN.

CONCLUSIONS

Repetitive obstructive respiratory events result in postapneic BP rises and renal hypoperfusion, as well as neurohumoral responses and increased protein/creatinine ratio. These changes are mainly sympathetically driven because they could be attenuated by RDN.

Excessive daytime sleepiness in type 2 diabetes

OBJECTIVE

To examine excessive daytime sleepiness (EDS) in type 2 diabetes.

SUBJECTS AND METHODS

Patients (N = 110) were evaluated regarding Epworth Sleepiness Scale (EDS), sleep quality (Pittsburgh Sleep Quality Index), depressive symptoms (Beck Depression Inventory), Restless Legs Syndrome (RLS), risk of obstructive sleep apnea (OSA) (Berlin questionnaire), and comorbidity severity (Charlson Comorbidity Index). Patients were compared with individuals with arterial hypertension and without diabetes.

RESULTS

Diabetic patients had more EDS, depressive symptoms, and higher comorbidity severity than hypertensive patients (p < 0.005). In diabetic patients, poor quality sleep (53.3%), and high risk of OSA (40.9%) and RLS (14.5%) were found; EDS (55.5%) was associated with depressive symptoms present in 44.5% individuals (OR = 1.08; 95% CI: 1.01-1.15), and remained so after data were controlled for age, gender, body mass index, and glycated hemoglobin (OR = 2.27; 95% CI 1.03-5.03).

CONCLUSIONS

Sleep abnormalities are frequent. EDS affects most of the patients and is independently associated with depressive symptoms. Adequate antidepressant therapy should be tested for the effects on EDS.

Hypoxemia and glycemic control in type 2 diabetes mellitus with extreme obesity

CONTEXT

Obstructive sleep apnea (OSA) has been shown to be associated with type 2 diabetes mellitus (DM). Studies on healthy individuals found that OSA is associated with lower insulin sensitivity. We hypothesized that nocturnal hypoxemia from OSA is associated with poorer glycemia in severely obese DM individuals.

DESIGN AND SETTING

This was a retrospective observational study of 122 non-DM, 126 non-insulin-treated DM, and 35 insulin-treated DM patients. Data were collected on demographic characteristics, body mass index, and comorbidities. An overnight sleep study was performed in all patients, and OSA was defined as an apnea-hypopnea index of ≥5 events/h.

RESULTS

There were more males (P = .003) and a lower proportion of white Europeans (P = .010) among DM patients. The prevalence of OSA was 80.1% in DM and 63.1% in non-DM individuals (P = .001). DM individuals also had lower oxygen saturation (O2) (P = .0106), greater percentage of time spent under 90% oxygen saturation (%TST<90%) (P = .0067), and higher apnea-hypopnea index (P = .0085). Regression analysis showed that %TST<90% and minimum O2 saturations were associated with worse hemoglobin A1c results among DM individuals. Every 10% reduction in minimum O2 was associated with a 0.3% increase in HbA1c, whereas a 10% increase in %TST<90% was associated with a 0.2% increase in hemoglobin A1c after adjusting for a range of potential confounders.

CONCLUSION

The high OSA prevalence in DM individuals and a positive relationship between nocturnal hypoxemia and glycemia supports the need to assess correction of hypoxemia as a management strategy for glycemic control.

Sleep apnea-hypopnea syndrome and type 2 diabetes. A reciprocal relationship?

Epidemiological data suggest that sleep apnea-hypopnea syndrome (SAHS) is independently associated with the development of insulin resistance and glucose intolerance. Moreover, despite significant methodological limitations, some studies report a high prevalence of SAHS in patients with type 2 diabetes mellitus (DM2). A recent meta-analysis shows that moderate-severe SAHS is associated with an increased risk of DM2 (relative risk=1.63 [1.09 to 2.45]), compared to the absence of apneas and hypopneas. Common alterations in various pathogenic pathways add biological plausibility to this relationship. Intermittent hypoxia and sleep fragmentation, caused by successive apnea-hypopnea episodes, induce several intermediate disorders, such as activation of the sympathetic nervous system, oxidative stress, systemic inflammation, alterations in appetite-regulating hormones and activation of the hypothalamic-pituitary-adrenal axis which, in turn, favor the development of insulin resistance, its progression to glucose intolerance and, ultimately, to DM2. Concomitant SAHS seems to increase DM2 severity, since it worsens glycemic control and enhances the effects of atherosclerosis on the development of macrovascular complications. Furthermore, SAHS may be associated with the development of microvascular complications: retinopathy, nephropathy or diabetic neuropathy in particular. Data are still scant, but it seems that DM2 may also worsen SAHS progression, by increasing the collapsibility of the upper airway and the development of central apneas and hypopneas.

Metabolic consequences of sleep and circadian disorders

Sleep and circadian rhythms modulate or control daily physiological patterns with importance for normal metabolic health. Sleep deficiencies associated with insufficient sleep schedules, insomnia with short-sleep duration, sleep apnea, narcolepsy, circadian misalignment, shift work, night eating syndrome, and sleep-related eating disorder may all contribute to metabolic dysregulation. Sleep deficiencies and circadian disruption associated with metabolic dysregulation may contribute to weight gain, obesity, and type 2 diabetes potentially by altering timing and amount of food intake, disrupting energy balance, inflammation, impairing glucose tolerance, and insulin sensitivity. Given the rapidly increasing prevalence of metabolic diseases, it is important to recognize the role of sleep and circadian disruption in the development, progression, and morbidity of metabolic disease. Some findings indicate sleep treatments and countermeasures improve metabolic health, but future clinical research investigating prevention and treatment of chronic metabolic disorders through treatment of sleep and circadian disruption is needed.

Comparative effectiveness research in obstructive sleep apnea: bridging gaps between efficacy studies and clinical practice

Comparative effectiveness research encompasses research that compares two interventions to each other, and takes place in real-world settings without strict inclusion and exclusion criteria, according to the established standard of care. There is a need for comparative evaluations of the treatments for obstructive sleep apnea, a disease associated with increased cardiovascular risk, stroke and metabolic derangement. This article reviews the recent, representative literature that addresses obstructive sleep apnea intervention and treatment, paradigms for diagnosis and randomized control trials addressing the efficacy of interventions, in an effort to demonstrate examples of both traditional observational and randomized control trials, as well as to illustrate the considerable overlap between some traditional studies and comparative effectiveness research. Despite methodological challenges, the potentially large clinical and public health impact of obstructive sleep apnea, accompanied by considerable cost, mandates that randomized controlled trials and comparative effectiveness research be systematically applied to identify both the efficacy and effectiveness of alternative diagnosis and treatment strategies.

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.

Obstructive sleep apnoea and diabetes: an update

PURPOSE OF REVIEW

The relationship between obstructive sleep apnoea (OSA) and dysglycaemia is well established. However, uncertainty remains as to the extent that obesity mediates this relationship. The impact of OSA treatment on glucose metabolism and the consequences of having OSA in patients with diabetes is unclear. This review aims to summarize the latest evidence regarding the links between OSA and dysglycaemia.

RECENT FINDINGS

OSA is associated with insulin resistance in lean individuals and predicts insulin resistance worsening longitudinally. Continuous positive airway pressure (CPAP) lowers insulin resistance in CPAP-compliant patients. OSA is associated with impaired β-cell function. In patients with type 2 diabetes (T2D), the association between OSA and glycosylated haemoglobin (HbA1c) is related to nocturnal hypoxaemia. Apnoea hypopnoea index (AHI) during rapid eye movement (REM) (not non-REM) sleep is associated with HbA1c. In-laboratory, supervised CPAP improves glycaemia. OSA is associated with and predicts the progression of some diabetic vascular complications. Intensive lifestyle intervention in patients with T2D improves OSA independent of weight loss.

SUMMARY

OSA is associated with insulin resistance and β-cell dysfunction independent of obesity. OSA is associated with HbA1c and vascular complications in patients with T2D. CPAP might improve insulin resistance and glycaemic measures. Lifestyle intervention has a significant impact on AHI in patients with T2D.

Unconstrained sleep apnea monitoring using polyvinylidene fluoride film-based sensor

We established and tested an unconstrained sleep apnea monitoring method using a polyvinylidene (PVDF) film-based sensor for continuous and accurate monitoring of apneic events occurred during sleep. Twenty-six sleep apnea patients and six normal subjects participated in this study. Subjects' respiratory signals were measured using the PVDF-based sensor during polysomnography. The PVDF sensor comprised a 4 × 1 array, and a thin silicon pad was placed over the sensor to prevent damage. Total thickness of the merged system was approximately 1.1 mm which was thin enough to prevent the subject from being consciously aware of its presence. It was designed to be placed under subjects' backs and installed between a bed cover and mattress. The proposed method was based on the standard deviation of the PVDF signals, and it was applied to a test set for detecting apneic events. The method's performance was assessed by comparing the results with a sleep physician's manual scoring. The correlation coefficient for the apnea-hypopnea index (AHI) values between the methods was 0.94 (p < 0.001). The areas under the receiver operating curves at three AHI threshold levels (>5, >15, and >20) for sleep apnea diagnosis were 0.98, 0.99, and 0.98, respectively. For min-by-min apnea detection, the method classified sleep apnea with an average sensitivity of 72.9%, specificity of 90.6%, accuracy of 85.5%, and kappa statistic of 0.60. The developed system and method can be applied to sleep apnea detection in home or ambulatory monitoring.

May diabetes patients have trouble sleeping despite not having obesity?

Obstructive sleep apnea (OSA) and periodic limb movements during sleep (PLMs) are sleep-related disorders with a high prevalence in type 2 diabetes. Commonly OSA is considered as a consequence of obesity, but several previous studies have shown the presence of OSA in non-obese diabetic patients. A previous study showed higher PLMs prevalence in patients with type 2 diabetes, compared to age-matched controls. We speculated that both OSA and PLMs may reflect the presence of diabetic autonomic neuropathy. To test this hypothesis, we compared a group of 112 non-obese patients with type 2 diabetes with 66 age-, sex-, and body mass index- matched nondiabetic patients. Both groups have been investigated through a set of tests including the Epworth Sleepiness Scale, polysomnography, and the Orthostatic Grading Scale (OGS), a questionnaire to assess the degree of autonomic dysfunction. Diabetic patients with OSA and PLMs scored higher on the OGS than controls. Our results confirm that both OSA and PLMs are related to dysautonomy and may be unrelated to obesity in type 2 diabetes patients.

Interactions between sleep, circadian function, and glucose metabolism: implications for risk and severity of diabetes

Sleep disturbances, including sleep insufficiency and sleep fragmentation, have been linked to abnormal glucose metabolism and increased diabetes risk. Well-controlled laboratory studies have provided insights regarding the underlying mechanisms. Several large prospective studies suggest that these sleep disturbances are associated with an increased risk of incident diabetes. Obstructive sleep apnea, which combines sleep fragmentation and hypoxemia, is a major risk factor for insulin resistance and possibly diabetes. Whether glycemic control in type 2 diabetes patients can be improved by treating sleep apnea remains controversial. Recently, sleep disturbances during pregnancy and their relationship to gestational diabetes and hyperglycemia have received considerable attention owing to potential adverse effects on maternal and fetal health. Additionally, evidence from animal models has identified disruption of the circadian system as a putative risk factor for adverse metabolic outcomes. The purpose of this review is to provide an update on the current state of knowledge linking sleep disturbances, circadian dysfunction, and glucose metabolism. Experimental, prospective, and interventional studies are discussed.

Obstructive sleep apnea: an unexpected cause of insulin resistance and diabetes

Obstructive sleep apnea (OSA) is prevalent with type 2 diabetes. Conversely, nondiabetic patients with OSA are at increased risk of developing insulin resistance and diabetes. These disorders independently contribute to increased cardiovascular and cerebrovascular morbidity and mortality. The pathophysiology of OSA may help explain these associations. Evidence demonstrates that treatment of OSA with continuous positive airway pressure may lead to improvement in insulin sensitivity, hemoglobin A1c, systemic hypertension, and other components of the metabolic syndrome. Recognizing and treating OSA in patients with insulin resistance or diabetes ameliorates OSA-related symptoms and improves cardiometabolic risk.

Obstructive Sleep Apnoea and Type 2 Diabetes

With the growing prevalence of obesity, the burden of type 2 diabetes is increasing. Obstructive sleep apnoea (OSA) is a very common medical condition that is associated with increased risk of cardiovascular disease and mortality. Obesity is a common risk factor for OSA and type 2 diabetes and hence it is not surprising that OSA and type 2 diabetes are interlinked. OSA has been shown to be an independent risk factor for the development of incident pre-diabetes/type 2 diabetes. OSA is also associated with worse glycaemic control and vascular disease in patients with type 2 diabetes. However, evidence for the benefits of OSA treatment in patients with type 2 diabetes is still lacking. The aim of this article is to provide an overview of OSA, the relationships between OSA and dysglycaemia and the impact of OSA in patients with type 2 diabetes, highlighting recent advances in the field.

Insights into obstructive sleep apnea research

Moderate to severe obstructive sleep apnea (OSA) occurs in 10-17% of middle aged men and 3-9% of middle-aged women with a higher prevalence among obese subjects. This condition is an independent risk factor for many cardiovascular diseases. Intermittent hypoxia is a major pathophysiologic character of OSA; it can lead to oxidative stress and inflammation, which in their turn cause endothelial dysfunction, a hallmark of atherosclerosis. Many animal models have been designed to mimic OSA in human patients to allow more in-depth investigation of biological and cellular mechanisms of this condition. This review discusses the cardiovascular outcomes of OSA and some of the animal models that are being used to investigate it.

The relationship and potential mechanistic pathways between sleep disturbances and maternal hyperglycemia

This paper reviews recent work investigating the influence of sleep disturbances on maternal hyperglycemia, particularly gestational diabetes mellitus (GDM). The incidence and prevalence of hyperglycemia are increasing worldwide, which is cause for concern because GDM and even mild hyperglycemia are associated with adverse pregnancy outcomes. A better understanding of sleep-related risk factors for maternal hyperglycemia is an important health matter. Evidence demonstrates associations between sleep disturbances, especially sleep-disordered breathing, and hyperglycemia, but causal effects and the underlying mechanisms linking these conditions have not been fully elucidated. Subjective sleep assessments show associations between sleep disturbances and maternal hyperglycemia. There are, however, few studies using objective measures to support these findings. Large prospective studies are required to examine causal relationships between sleep disturbances and maternal hyperglycemia. There is also a need for smaller mechanistic studies to understand the pathophysiology. Furthermore, interventional studies are required to address whether improvement of sleep parameters can prevent/decrease the risk of developing maternal hyperglycemia. Taken together, the data suggests that sleep disturbances during pregnancy are important to identify and manage in order to minimize maternal hyperglycemia and GDM, and improve maternal and fetal well-being.

Obstructive Sleep Apnea and Surgery: Quality Improvement Imperatives and Opportunities

Obstructive sleep apnea (OSA) is more common in surgical candidates than in the general population and may increase susceptibility to perioperative complications that range from transient desaturation to catastrophic injuries. Understanding the potential impact of OSA on patients' surgical risk profile is of particular interest to otolaryngologists, who routinely perform airway procedures-including surgical procedures for treatment of OSA. Whereas the effects of OSA on long-term health outcomes are well documented, the relationship between OSA and surgical risk is not collinear, and clear consensus on the nature of the association is lacking. Better guidelines for optimization of pain control, perioperative monitoring, and surgical decision making are potential areas for quality improvement efforts. Many interventions have been suggested to mitigate the risk of adverse events in surgical patients with OSA, but wide variations in clinical practice remain. We review the current literature, emphasizing recent progress in understanding the complex pathophysiologic interactions noted in OSA patients undergoing surgery and outlining potential strategies to decrease perioperative risks.

Sleep and insulin-like growth factors in the Cardiovascular Health Study

STUDY OBJECTIVES

Sleep and sleep disordered breathing (obstructive sleep apnea [OSA]) are known to affect the growth hormone/insulin-like growth factor (GH/IGF) axis. There are few relevant population studies in this area, particularly in the elderly. We conducted this study to investigate the relationship between sleep (architecture and OSA) and circulating IGF-I (insulin-like growth factor-1), IGFBP-1 (insulin-like growth factor binding protein-1), and IGFBP-3 (insulin-like growth factor binding protein-3) levels in an elderly population.

DESIGN SETTING

Cross-sectional analysis of participants from the year 9 visit of the Cardiovascular Health Study (CHS) who were enrolled in the Sleep Heart Health Study (SHHS).

PATIENTS OR PARTICIPANTS

1,233 elderly participants from the CHS and SHHS.

MEASUREMENTS AND RESULTS

The mean age of males (n = 526) and females (n = 697) was 77 years. The mean value of IGF-I (ng/mL) in males was 112.4 vs. 97.1 in females (p < 0.01). Mean IGFBP-1 and IGFBP-3 levels were higher in females than males (p < 0.01). As expected, slow wave sleep was better preserved in females compared to males (22% total sleep time vs. 9% total sleep time, p < 0.01). Furthermore, as expected, OSA (apneahypopnea index [AHI] ≥ 5/h) was more prevalent in males compared to females (60% vs. 46%, p < 0.01). Multivariable linear regression was used to determine the relationship between objective sleep parameters and circulating IGF-I, IGFBP-1, and IGFBP-3 levels, with adjustment for age, sex, race, BMI, diabetes, estrogen use, progestin use, and physical activity. We did not detect a significant association between slow wave sleep (SWS) (per 5 min) and IGF-I, IGFBP-1, and IGFBP-3 levels (ng/mL). We found no significant linear association between OSA (AHI ≥ 5/h) and IGF-I, IGFBP-1, and IGFBP-3 levels. Gender-stratification of the entire cohort did not alter these findings. Sensitivity analyses excluding diabetics revealed that moderate OSA (AHI ≥ 5 and < 15) is inversely associated with IGFBP-3 levels in women. Conclusions The relationship between SWS and GH/IGF system is not significant in the elderly. Furthermore, OSA does not appear to adversely influence the GH/IGF axis, as reported in younger individuals. Whether our study findings are due to diminished GH/IGF-I axis activity in elderly needs further investigation by replication in other large population based elderly cohorts.

The Relationship between Diabetic Neuropathy and Sleep Apnea Syndrome: A Meta-Analysis

Aims. High prevalence of sleep apnea syndrome (SAS) has been reported in patients with diabetes. However, whether diabetic neuropathy (DN) contributes to this high prevalence is controversial. Our aim of this study is to compare the prevalence of SAS between patients with and without DN. Methods. Systematic literature searches were conducted for cross-sectional studies that reported the number of patients with DN and SAS using MEDLINE (from 1966 to Nov 5, 2012) and EMBASE (from 1974 to Nov 5, 2012). Odds ratios (ORs) of SAS related to DN were pooled with the Mantel-Haenszel method. Results. Data were obtained from 5 eligible studies (including 6 data sets, 880 participants, and 429 cases). Overall, the pooled OR of SAS in patients with DN compared with that in non-DN patients was significant (OR (95% CI), −1.95 (1.03–3.70)). The pooled OR of SAS was 1.90 (0.97–3.71) in patients with type 2 diabetes. Excluding data on patients with type 1 diabetes, a higher OR was observed in younger patients (mean age <60 years) than in those ≥60 years among whom the OR remained significant (3.82; 95% CI, 2.24–6.51 and 1.17; 95% CI, 0.81–1.68). Conclusions. Current meta-analysis suggested the association of some elements of neuropathy with SAS in type 2 diabetes. Further investigations are needed to clarify whether the association is also true for patients with type 1 diabetes.

Establishing visit priorities for complex patients: A summary of the literature and conceptual model to guide innovative interventions

With the aging of the population and continuing advances in health care, patients seen in the primary care setting are increasingly complex. At the same time, the number of screening and chronic condition management tasks primary care providers are expected to cover during brief primary care office visits has continued to grow. These converging trends mean that there is often not enough time during each visit to address all of the patient's concerns and needs, a significant barrier to effectively providing patient-centered care. For complex patients, prioritization of which issues to address during a given visit must precede discrete decisions about disease-specific treatment preferences and goals. Negotiating this process of setting priorities represents a major challenge for patient-centered primary care, as patient and provider priorities may not always be aligned. In this review, we present a synthesis of recent research on how patients and providers negotiate the visit process and describe a conceptual model to guide innovative approaches to more effective primary care visits for complex patients based on defining visit priorities. The goal of this model is to inform interventions that maximize the value of available time during the primary care encounter by facilitating communication between a prepared patient who has had time before the visit to identify his/her priorities and an informed provider who is aware of the patient's care priorities at the beginning of the visit. We conclude with a discussion of key questions that should guide future research and intervention development in this area.

The potential association between obstructive sleep apnea and diabetic retinopathy in severe obesity-the role of hypoxemia

Background

Obstructive sleep apnea (OSA) is common in obese patients with type 2 diabetes mellitus (DM) and may contribute to diabetic microvascular complications.

Methods

To investigate the association between OSA, hypoxemia during sleep, and diabetic retinal complications in severe obesity. This was a prospective observational study of 93 obese patients mean (SD) age: 52(10) years; mean (SD) body mass index (BMI): 47.3(8.3) kg/m²) with DM undergoing retinal screening and respiratory monitoring during sleep. OSA was defined as apnea-hypopnea index (AHI) of ≥15 events/hour, resulting in two groups (OSA+ vs. OSA−).

Results

Forty-six patients were OSA+: median (95% CI) AHI = 37(23–74)/hour and 47 were OSA–ve (AHI = 7(4–11)/hour). Both groups were similar for ethnicity, BMI, cardiovascular co-morbidities, diabetes duration, HbA_1c, and insulin treatment (p>0.05). The OSA+ group was significantly more hypoxemic. There was no significant difference between OSA+ and OSA− groups for the presence of retinopathy (39% vs. 38%). More OSA+ subjects had maculopathy (22% vs. 13%), but this did not reach statistical significance. Logistic regression analyses showed that AHI was not significantly associated with the presence of retinopathy or maculopathy (p>0.05). Whilst minimum oxygen saturation was not significantly associated with retinopathy, it was an independent predictor for the presence of maculopathy OR = 0.79 (95% CI: 0.65–0.95; p<0.05), after adjustment.

Conclusions

The presence of OSA, as determined by AHI, was not associated with diabetic retinal complications. In contrast, severity of hypoxemia during sleep (minimum oxygen saturations) may be an important factor. The importance of hypoxia in the development of retinal complications in patients with OSA remains unclear and further studies assessing the pathogenesis of hypoxemia in patients with OSA and diabetic retinal disease are warranted.

Are diabetic patients being screened for sleep related breathing disorder?

Prevalence of both diabetes mellitus and obstructive sleep apnea (OSA) is high among general population. Both of these conditions are associated with significant morbidity. OSA affects approximately 25% of men and 9% of women, and its prevalence is even higher among obese, Hispanics, African American and diabetic patients. Diabetes on the other hand besides having high prevalence in general population has even higher prevalence among ethnic populations as Hispanics and African American. Despite the availability of several simple screening tools for OSA, as Berlin questionnaire, STOP-BANG questionnaire, NAMES Criteria, the utility for screening of OSA among the diabetic population remains marginal. This in turn can lead to significant morbidity and complications related to OSA as well as worsening of diabetes mellitus and increase in diabetic complications due to untreated sleep related breathing disorder. It is therefore imperative for the primary care giver to screen for OSA among the diabetic population as a part of their routine evaluation to prevent worsening of diabetes, and its cardiovascular, renal, ophthalmologic and neurological complications.

Association of obstructive sleep apnoea with subclinical coronary atherosclerosis

BACKGROUND

Accumulating evidence suggests a role of obstructive sleep apnoea (OSA) as a risk factor for coronary atherosclerosis. This study aimed i) to assess the prevalence of OSA in the general population and ii) to analyse the association of this disorder with traditional cardiovascular disease risk factors and subclinical coronary atherosclerosis.

METHODS

In a cross-sectional analysis of the Heinz Nixdorf Recall study a subgroup of 1604 subjects (791 men, age 50-80 years) underwent OSA screening. Furthermore, coronary artery calcium (CAC) was measured. OSA was defined as apnoea-hypopnoea index (AHI) ≥ 15/h.

RESULTS

OSA was observed in 29.1% of men and 15.6% of women. In a multiple linear regression analysis adjusted for risk factors AHI was associated with CAC in men aged ≤65 years (estimated log-transformed increase of CAC = 0.25, 95% confidence interval (CI) = -0.001-0.50, p = 0.051) and in women of any age (estimated log-transformed increase = 0.23, 95% CI = 0.04-0.41, p = 0.02). Doubling of the AHI was associated with a 19% increase of CAC in men aged ≤65 years and with a 17% increase in women of any age.

CONCLUSIONS

In the general population aged ≥50 years OSA is associated with subclinical atherosclerosis in men aged ≤65 years and in women of any age, independent of traditional cardiovascular risk factors.

Binge drinking and sleep problems among young adults

OBJECTIVE

As most of the literature exploring the relationships between alcohol use and sleep problems is descriptive and with small sample sizes, the present study seeks to provide new information on the topic by employing a large, nationally representative dataset with several waves of data and a broad set of measures for binge drinking and sleep problems.

METHODS

We use data from the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative survey of adolescents and young adults. The analysis sample consists of all Wave 4 observations without missing values for the sleep problems variables (N=14,089, 53% females). We estimate gender-specific multivariate probit models with a rich set of socioeconomic, demographic, physical, and mental health variables to control for confounding factors.

RESULTS

Our results confirm that alcohol use, and specifically binge drinking, is positively and significantly associated with various types of sleep problems. The detrimental effects on sleep increase in magnitude with frequency of binge drinking, suggesting a dose-response relationship. Moreover, binge drinking is associated with sleep problems independent of psychiatric conditions.

CONCLUSIONS

The statistically strong association between sleep problems and binge drinking found in this study is a first step in understanding these relationships. Future research is needed to determine the causal links between alcohol misuse and sleep problems to inform appropriate clinical and policy responses.

Cephalometric evaluation of mandibular advancement at different horizontal jaw positions in obstructive sleep apnoea patients: a pilot study

BACKGROUND

The aim of this study was to comparatively evaluate the efficacy of the mandibular advancement device (MAD) at 50% (P2) and 75% (P3) of maximum mandibular advancement, relative to maximum intercuspation (P1) subjectively and objectively.

METHODS

Eighteen subjects previously diagnosed with obstructive sleep apnoea (OSA) were selected for the study. ESS score, VAS score, soft palate angle, MP-H distance, S-H distance, a C4 -H distance, a Pu -p Pu distance and total pharyngeal area were calculated at P1, P2 and P3 positions with the help of an adjustable MAD. The results were statistically analysed.

RESULTS

ESS score, VAS score, soft palate angle, MP-H distance, S-H distance and radius of curvature of airway at P2 and P3 were significantly lower compared to P1, but there was no significant difference between P2 and P3.

CONCLUSIONS

The MAD produced significant improvement in objective signs and subjective symptoms at both 50% and 75% of the maximum mandibular protrusion positions at comparable comfort levels. Therefore, MAD may be given at 50% of maximum advancement in order to reduce dental or temporomandibular joint disturbances.

Preliminary evidence that obese patients with obstructive sleep apnea/hypopnea syndrome are refractory to the acute beneficial metabolic effects of a very low calorie diet

Since obesity seems to play a causal role in both obstructive sleep apnea/hypopnea syndrome (OSAHS) and type 2 diabetes, the question arises whether diet-induced weight loss is equally efficacious in type 2 diabetic patients with and without OSAHS. The present study was aimed to investigate the effect of 1 week very low calorie diet (VLCD) on oxygen desaturation index (ODI) and on glucose regulation in OSAHS versus non-OSAHS patients. Fourteen patients with type 2 diabetes mellitus and morbid obesity were enrolled. According to ODI, patients were divided into 2 groups (with and without OSAHS) and evaluated by a hyperglycemic clamp study, before and after a 7 day-VLCD. After a VLCD, a significant reduction of anthropometric parameters, in the overall group and in subgroups, was observed. M-value and acute insulin response increased significantly only in patients without obstructive sleep apnea (990.10 ± 170.19 vs. 1,205.22 ± 145.73 μmol min(-1) m(-2), p = 0.046; -1.05 ± 8.40 vs. 48.26 ± 11. 90 pmol/L, p = 0.028, respectively). The average 24-h heart rate (24-h HR) fell significantly (p = 0.05), primarily because of a decrease during daytime (p = 0.041), in the whole group. In conclusion, we observed that morbidly obese patients with type 2 diabetes and OSAHS are specifically resistant to the acute beneficial effects of VLCD on metabolic parameters. Our preliminary observation deserves further investigation to clarify the pathogenetic mechanisms involved.

Serum brain-derived neurotrophic factor levels are associated with dyssomnia in females, but not males, among Japanese workers

STUDY OBJECTIVES

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors that promote the growth and survival of neurons. Recent evidence suggests that BDNF is a sleep regulatory substance that contributes to sleep behavior. However, no studies have examined the association between the serum BDNF levels and dyssomnia. The present study was conducted to clarify the association between the serum BDNF levels and dyssomnia.

METHODS

A total of 344 workers (age: 40.1 ± 10.5 years, male: 204, female: 140) were included in the study. The serum BDNF levels were categorized into tertiles according to sex.

RESULTS

The prevalence of dyssomnia was 35.1% in males and 30.0% in females. In the females, the BDNF levels were found to be negatively associated with dyssomnia after adjusting for age, body mass index, hypertension, dyslipidemia, hyperglycemia, depression, smoking, alcohol intake, and regular exercise. Compared with the females in the high BDNF group, the multivariate odds ratio (95% CI) of dyssomnia was 2.08 (0.62-6.98) in females in the moderate BDNF group and 8.41 (2.05-27.14) in females in the low BDNF group. No such relationships were found in the males.

CONCLUSIONS

The serum BDNF levels are associated with dyssomnia in Japanese female, but not male, workers.

Targeted case finding for OSA within the primary care setting

STUDY OBJECTIVES

The aim was to determine the feasibility of using an unattended 2-channel device to screen for obstructive sleep apnea in a population of high-risk patients using a targeted, case-finding strategy. The case finding was based on the presence of risk factors not symptoms in the studied population.

METHODS

The study took place from June 2007 to May 2008 in rural and metropolitan Queensland and New South Wales. Family doctors were asked to identify patients with any of the following: BMI > 30, type 2 diabetes, treated hypertension, ischemic heart disease. Participants applied the ApneaLink+O2 at home for a single night. The device recorded nasal flow and pulse oximetry. Data were analyzed by proprietary software, then checked and reported by either of two sleep physicians.

RESULTS

1,157 patients were recruited; mean age 53 ± 14.6, M/F% = 62/38, mean BMI = 31.8, obesity = 35%, diabetes = 16%, hypertension = 39%, IHD = 5%, Mean Epworth Sleepiness Scale score (ESS) = 8.3. The prevalence of unrecognized OSA was very high: 71% had an AHI > 5/h, 33% had an AHI > 15/h, and 16% had an AHI > 30/h. The ApneaLink+O2 device yielded technically adequate studies in 93% of cases.

CONCLUSION

The study shows that a "real world" simple low cost case finding and management program, based on unattended home monitoring for OSA, can work well in a population with risk factors and comorbidities associated with OSA, independent of the presence of symptoms. The prevalence of unrecognized OSA was very high.

Sensitization of upper airway mechanoreceptors as a new pharmacologic principle to treat obstructive sleep apnea: investigations with AVE0118 in anesthetized pigs

STUDY OBJECTIVES

Drug treatment for obstructive sleep apnea (OSA) is desirable because at least 30% of patients do not tolerate continuous positive airway pressure (CPAP) treatment. The negative pressure reflex (NPR) involving superficially located mechanoreceptors in the upper airway (UA) is an important mechanism for UA patency inhibitable by topical UA anesthesia (lidocaine). The NPR may serve as a target for pharmacological intervention for a topical treatment of OSA. The objective was to determine the effect of pharmacological augmentation of the NPR on UA collapsibility.

DESIGN

We developed a model of UA collapsibility in which application of negative pressures caused UA collapses in spontaneously breathing α-chloralose-urethane anesthetized pigs as indicated by characteristic tracheal pressure and air flow changes.

SETTING

N/A.

PATIENTS OR PARTICIPANTS

N/A.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

The potassium channel blocker AVE0118 administered topically to the UA in doses of 1, 3, and 10 mg per nostril sensitized the NPR, shifting the mechanoreceptor response threshold for the genioglossus muscle to more positive pressures (P < 0.001; n = 6 per group) and dose-dependently inhibited UA collapsibility. Ten mg of AVE0118 prevented UA collapses against negative pressures of -150 mbar (P < 0.01) for > 4 h in all pigs, while in control pigs the UA collapsed at -50 mbar or less negative pressures. The effect of AVE0118 was abolished by UA lidocaine anesthesia. Acute intravenous administration of naloxone or acetazolamide was ineffective; paroxetine and mirtazepine were weakly effective and fluoxetine was moderately effective in line with reported clinical efficacy.

CONCLUSION

Topical administration of AVE0118 to the UA is a promising pharmacologic approach for the treatment of OSA.

Obstructive sleep apnoea and type 2 diabetes mellitus: a bidirectional association

Obstructive sleep apnoea and type 2 diabetes are common medical disorders that have important clinical, epidemiological, and public health implications. Research done in the past two decades indicates that obstructive sleep apnoea, through the effects of intermittent hypoxaemia and sleep fragmentation, could contribute independently to the development of insulin resistance, glucose intolerance, and type 2 diabetes. Conversely, type 2 diabetes might increase predisposition to, or accelerate progression of, obstructive and central sleep apnoea, possibly through the development of peripheral neuropathy and abnormalities of ventilatory and upper airway neural control. Although more research is needed to clarify the mechanisms underlying the bidirectional association between the two disorders, their frequent coexistence should prompt all health-care professionals to embrace clinical practices that include screening of a patient presenting with one disorder for the other. Early identification of obstructive sleep apnoea in patients with metabolic dysfunction, including type 2 diabetes, and assessment for metabolic abnormalities in those with obstructive sleep apnoea could reduce cardiovascular disease risk and improve the quality of life of patients with these chronic diseases.

Fatigue and Related Factors in People With Type 2 Diabetes

Purpose

The purpose of this study was to examine the presence and severity of fatigue in people with type 2 diabetes.

Methods

The Fatigue Severity Scale (FSS), Fatigue Assessment Scale (FAS), and Visual Analog Fatigue Scale (VAFS) were administered by anonymous survey of 37 individuals with and 33 individuals without diabetes to assess the presence of fatigue. Data on age, gender, weight, height, year of diagnosis, and number/type of complications were also collected. Nonparametric tests tested for differences in fatigue measures between the groups, and distribution characteristics of the FAS, FSS, and VAFS scores were examined. Spearman rank correlation coefficients examined the relationships between the variables.

Results

People with diabetes scored higher on all 3 fatigue assessment scales as compared to controls (FAS: 25.11 vs 19.94, P = .001; FSS: 4.30 vs 2.59, P = .000; VAFS: 4.64 vs 1.75, P = .000). Data were normally distributed for FSS in the group with diabetes and the group without diabetes, and scores of FAS, FSS, and VAFS showed no ceiling effects. A positive correlation was noted between fatigue measures and number of complications ( r = .482; P = .003).

Conclusions

Higher levels of fatigue were noted in people with type 2 diabetes as compared to healthy age-matched control; however, the cause and impact of these changes remain unclear. FSS is a recommended tool for measuring fatigue in this population. Further studies are needed to explore the contributing factors to fatigue in those with diabetes.

Less variation of R-R interval of electrocardiogram in nonobese type 2 diabetes with nocturnal intermittent hypoxia

Obesity is a major risk factor for sleep-disordered breathing (SDB). However, many Japanese subjects with diabetes are less obese despite compared with Caucasian. We evaluated the relationship between SDB and clinical characteristics other than obesity, especially in relation to cardiac autonomic neuropathy (CAN) in Japanese subjects with diabetes. The study included a total of 261 consecutive Japanese subjects with type 2 diabetes, including nonobese subjects defined as BMI <25 kg/m² for Japanese. SDB was screened by 4% oxygen desaturation index (ODI) level of 5 or more events per hour, which was measured by nocturnal pulse oximetry. CAN was examined with the variation of R-R intervals (CVRR). The SDB were found in 24.5% of total subjects and 16.3% of nonobese subjects with type 2 diabetes, respectively. The nonobese type 2 diabetes subjects with SDB had significantly lower coefficient of CVRR than those without SDB. Multiple regression analysis revealed that BMI and heart rate were significant independent factors for SDB in total subjects with type 2 diabetes, but CVRR was the only significant independent factor for SDB in nonobese subjects with type 2 diabetes. These findings suggest that the presence of SDB should be kept in mind in type 2 diabetic patients with abnormality in CVRR variation in electrocardiogram even though they are not obese.

Expanding role of the Madras Diabetes Research Foundation - Indian Diabetes Risk Score in clinical practice

The Indian Diabetes Risk Score was initially developed by the Madras Diabetes Research Foundation (MDRF-IDRS) to help detect undiagnosed Type 2 diabetes (T2DM) in the community. Soon it was found that the MDRF-IDRS could also help to predict incident diabetes, metabolic syndrome, coronary artery disease (CAD), non-alcoholic fatty liver disease as well as sleep disorders in the community. It helps to differentiate T2DM from non-T2DM. Finally, it also helps to identify those with CAD, peripheral vascular disease and neuropathy among those with T2DM. Thus, the MDRF-IDRS is a simple, virtually 'no cost' tool which is useful in several clinical and epidemiological settings.