Does physical exercise reduce excessive daytime sleepiness by improving inflammatory profiles in obstructive sleep apnea patients?

Oxidative Stress and Inflammation Biomarker Expression in Obstructive Sleep Apnea Patients

Obstructive Sleep Apnea Syndrome (OSAS) is a respiratory sleep disorder characterised by repeated episodes of partial or complete obstruction of the upper airway during the night. This obstruction usually occurs with a reduction (hypopnea) or complete cessation (apnea) of the airflow in the upper airways with the persistence of thoracic-diaphragmatic respiratory movements. During the hypopnea/apnea events, poor alveolar ventilation reduces the oxygen saturation in the arterial blood (SaO₂) and a gradual increase in the partial arterial pressure of carbon dioxide (PaCO₂). The direct consequence of the intermittent hypoxia is an oxidative imbalance, with reactive oxygen species production and the inflammatory cascade’s activation with pro and anti-inflammatory cytokines growth. Tumour necrosis factors, inflammatory cytokines (IL2, IL4, IL6), lipid peroxidation, and cell-free DNA have been found to increase in OSAS patients. However, even though different risk-related markers have been described and analysed in the literature, it has not yet been clarified whether specified inflammatory bio-markers better correlates with OSAS diagnosis and its clinical evolution/comorbidities. We perform a scientific literature review to discuss inflammatory and oxidative stress biomarkers currently tested in OSAS patients and their correlation with the disease’s severity and treatment.

Natural Cannabinoids as Templates for Sleep Disturbances Treatments

The sleep-wake cycle is a complex composition of specific physiological and behavioral characteristics. In addition, neuroanatomical, neurochemical and molecular systems exerts influences in the modulation of the sleep-wake cycle. Moreover, homeostatic and circadian mechanisms interact to control the waking or sleeping states. As many other behaviors, sleep also develops pathological features that include several signs and symptoms corresponding to medical conditions known as sleep disorders.In addition to the neurobiological mechanisms modulating sleep, external elements also influence the sleep-wake cycle, including the use of Cannabis sativa (C. sativa). In this regard, and over the last decades, the interest of studying the pharmacology of Δ⁹-tetrahydrocannabinol (Δ⁹-THC), the principal psychoactive constituent of C. sativa, has been addressed. Moreover, in recent years, the focus of scientific interest has moved on to studying the second plant constituent with non-psychotropic pharmacological properties: Cannabidiol (CBD).The pharmacological and pharmaceutical interest of CBD has been focus of attention due to the accumulating body of evidence regarding the positive outcomes of using CBD for the treatment of several health issues, such as psychiatric and neurodegenerative disorders, epilepsy, etc. Since the most prominent sleep disruptions include excessive daytime sleepiness (EDS), current treatments include the use of drugs such as stimulants of antidepressants. Notwithstanding, side effects are commonly reported among the patients under prescription of these compounds. Thus, the search of novelty therapeutical approaches aimed to treat ESD may consider the use of cannabinoid-derived compounds, such as CBD. In this chapter, we will show experimental evidence regarding the potential role of CBD as a wake-inducing compound aimed to manage EDS.

Assessment of vitamin D, exercise, and lipid profile associated with excessive daytime sleepiness in school children

Previous research reported associations of excessive daytime sleepiness (EDS) with a low vitamin D level, obesity, and sexual maturity. The aim of this study was to identify the association and rank the importance of these with EDS. This study examined 618 children who were 10-12 year-old. The pediatric daytime sleepiness scale (PDSS) was used to evaluate EDS and sleep patterns. EDS was defined as a total PDSS score above 17. We ranked the importance of the relationship of these factors with EDS using random forest analysis. EDS (n = 111, 18%) was positively associated with more advanced pubertal stage in girls, chronic cough, urticaria, and allergic rhinitis. Multivariable analysis with adjustment for confounding indicated that children with low level of 25-hydroxyvitaminD₃ (25(OH)D₃ (<20 ng/mL) and high-density lipoprotein-cholesterol (HDL-C) (<40 mg/dL) levels had an increased risk of EDS (25(OH)D₃:adjusted odds ratio [aOR] = 1.73; 95% confidence interval [CI]: 1.06 to 2.81; P = 0.028; HDL-C: aOR = 2.84; 95% CI: 1.05 to 7.68; P = 0.039). Random forest analysis indicated that 25(OH)D₃ level, exercise, and body mass index (BMI) were over three. This study indicated high levels of 25-(OH)D₃ and HDL-C and performing regular exercise decreased the risk of EDS.

Effect of Sudarshan Kriya Yoga (SKY) on daytime and situational sleep propensity in novice practitioners: a prospective cohort study

OBJECTIVES

Hectic, late-night lifestyle has reduced 90 min sleep in 20% adults resulting in insomnia and excessive daytime sleepiness (EDS). We assess the scope of Sudarshan Kriya Yoga (SKY), a 4-component, breathing process in reducing EDS, generally and situationally.

METHODS

This is a prospective, controlled study involving randomized subjects without any sleep-wake cycle anomalies and prior experience in SKY. Subjects (n=52) performed 30 min of SKY for 6 days/week for 8 weeks, while controls (n=53) performed sitting activity and Suryanamaskar for 4-weeks each. Epworth Sleepiness Scale (ESS) was used to measure EDS at 0, 4, and 8 weeks.

RESULTS

SKY group showed significant ESS score improvements between 0-4 weeks and 4-8 weeks of 1.22 (p=0.0001) and 1.66 (p=0.001) respectively. Controls however failed to improve with score differences of 0.02 (p=0.892) and 0.02 (p=0.8212) respectively. SKY group showed significant ESS score improvement over controls at 4-weeks (difference=1.74; p=0.013) and 8-weeks (difference eight; p=0.0001). Improvement was most for obese people and those sitting in a halted car.

CONCLUSIONS

Improvement in subjects' nighttime sleep and daytime wakefulness in SKY practitioners can be attributed to polyvagal theory. Increased heart rate variability (HRV) alterations and sympathetic hyperarousal in chronic insomnia; and cholinergic and GABAergic dysregulation in anxiety disorders are countered by regulated vagal nerve stimulation post SKY. Our study establishes effectivity of SKY in reducing EDS (total and situational), provides a clinical correlation for prior polysomnographic evidence and paves way for larger trials directed towards SKY prescriptions for insomnia.

The implementation of a physical activity intervention in adults with Obstructive Sleep Apnoea over the age of 50 years: a feasibility uncontrolled clinical trial

Background

Obstructive Sleep Apnoea (OSA) is a risk factor for cardiovascular disease (CVD) and Type 2 diabetes (T2D). Observational studies suggested that OSA treatment might reduce CVD and T2D but RCTs failed to support these observations in part due to poor adherence to continuous positive airway pressure (CPAP). Physical activity (PA) has been shown to have favourable impact on CVD and the risk of T2D independent of its impact on weight and therefore might provide additional health gains to patients with OSA, whether or not adherent to CPAP.

Methods

The main aim of this study was to explore the feasibility of providing a 12-week PA intervention to adults aged over 50 with OSA. The secondary aim was to assess the impact of the PA intervention on OSA severity. Patients with moderate-severe OSA (apnoea hypopnea index (AHI) ≥ 15 events/hour (based on overnight ApneaLink™) were recruited in response to posters displayed in workplaces. A 12-week daily PA intervention was delivered in participant’s home setting and PA was monitored via text and validated by objective PA measures (GT3X accelerometers).

Results

The intervention was feasible as all 10 patients (8 males, mean (SD) age 57.3 (6.01)) completed the intervention and PA increased across the 12-weeks. The duration of PA increased from baseline (113.1 min (64.69) per week to study-end following the intervention (248.4 min (148.31) (p = 0.02). Perceived Exertion (RPE) (physical effort) increased significantly between baseline (M = 10.7 (1.94)) to end of intervention (M = 13.8, (1.56) (p < 0.001). The intervention had no significant impact on weight or composition. Following the intervention, there was a statistically non-significant a reduction in AHI from baseline to study end (22.3 (7.35) vs. 15.8 (7.48); p = 0.09).

Conclusion

It is feasible to deliver a PA intervention to adults aged over 50 with OSA. The intervention resulted in improved PA and AHI levels somewhat and seemingly independent of weight changes. Future trials need to examine whether PA can reduce the burden of OSA associated comorbidities.

Trial registration

CTN: ISRCTN11016312 Retrospectively Registered 21/07/20.

To Study the Effect of Calorie Deficit Diet and Strength Training in Patients with Mild to Moderate Obstructive Sleep Apnoea

OSA is a disease of modernisation. Though many modalities are available for its treatment from invasive to non-invasive; the role of lifestyle modification can never be underrated. Lifestyle modification normally includes walk; diet with less fat; abstinence from alcohol and smoking along with regularising of sleep schedule. However the role of calorie deficit diet along with strength training in OSA has not been extensively researched till date. The present study aimed to evaluate the effect of the calorie deficit diet and strength training in patients with mild to moderate obstructive sleep apnea. It is a prospective randomised control trial of 40 patients. The patients were divided into 2 groups. Group A was given lifestyle modification while Group B was given Lifestyle Modification with calorie deficit diet and strength training. The outcomes were measured by comparing pre-intervention and post-intervention polysomnography and Epworth sleepiness score after 3 months. The most common symptom found in our group was excessive daytime sleepiness and Loud snoring; both present in 39/40 patients. Other common symptoms were Awakening with a dry mouth or sore throat; morning headache; difficulty concentrating during the day; experiencing mood changes, such as depression or irritability and high blood pressure. The post intervention BMI in Group A was - 1.75 ± 0.698 than pre-intervention BMI while in Group B the difference between pre-intervention and post intervention was - 3.05 ± 1.32. The difference in AHI events pre-intervention versus post-intervention in Group A and Group B was - 3.5 ± 1.11 and - 5.55 ± 1.90 respectively. The ESS decreased by - 2.2 ± 0.871 and - 3.31 ± 0.05 respectively in Group A and Group B post-intervention. Calorie deficit diet along with strength training markedly improves the AHI index; BMI and ESS score in Mild to moderate OSA patients and is highly recommended in motivated patients in addition to lifestyle modification.

Association of Depression and Excessive Daytime Sleepiness among Sleep-Deprived College Freshmen in Northern Taiwan

Background. The aim of this study was to investigate depression and other determinants (sleep-deprived behaviors such as hours spent sleeping, watching television, and on the computer) and their association with excessive daytime sleepiness (EDS) among college freshmen. Methods. Self-administered questionnaires were collected from two colleges in northern Taiwan from July to September 2014. A total of 2643 students (38.7% male; ages ranged 18–23 years; mean age of 18.8 ± 1.2 years) completed an anonymous questionnaire on lifestyle behaviors (including personal habits, sleep duration and quality, and hours spent watching television and on the computer); perception of one’s health, a validated depression scale (Brief Symptom Rating Scale, BSRS-5); insomnia symptoms (the Chinese version of the Athens Insomnia Scale, CAIS); and EDS rated with the Chinese Epworth sleepiness scale (CESS). The data were analyzed using the chi-squared test, t-test, multivariate logistic regression, and multiple linear regression. Results. The prevalence of EDS among college students was approximately 27.1% (717/2643). The risk of EDS was elevated with increasing severity of depression: odds ratio (OR) = 2.8/3.71/5.01 for female, and OR = 3.29/5.07/5.07 for mild/moderate/severe depression for male, respectively (p < 0.05; marginally higher in male severe depression, p = 0.08). If depression score increased by 1 point, CESS score increased by 0.35 point; if time spent on the computer during non-holidays increased by 1 h, CESS score increased by 0.1 point; and for those whose sleep duration increased by 1 h during non-holidays, CESS score decreased by 0.1 point. Conclusions. EDS significantly predicted depression among college freshmen. Using a computer for a long time and less sleep duration during non-holidays contributed to EDS of college freshmen. Youths who experience EDS are recommended to seek assessment for depression symptoms and sleep-deprived behaviors, thus allowing physicians to offer appropriate screening and treatment.

Oxidative stress and inflammatory profiles in obstructive sleep apnea: are short-term CPAP or aerobic exercise therapies effective?

PURPOSE

The effects of medium to long-term continuous positive airway pressure (CPAP) or physical activity in decreasing oxidative stress, inflammatory, and cell-free DNA markers in obstructive sleep apnea (OSA) have been explored. Here we evaluate oxidative stress markers (TBARS, AOPP, SOD), proinflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8), anti-inflammatory cytokines (IL-4, IL-10), and cell-free DNA levels before and after 8-week CPAP treatment or moderate-intensity aerobic training in moderate to severe OSA.

METHODS

Thirty-nine patients diagnosed with OSA were randomly divided into CPAP (N = 18), with or without humidifier, and exercise groups (N = 21). Excessive daytime sleepiness and sleep quality were assessed by the Epworth Sleepiness Scale and the Pittsburgh questionnaire, respectively. Biomarkers for lipid and protein oxidation, pro and anti-inflammatory cytokines, and cell-free DNA were quantified in blood samples, before and after 8 weeks of both treatments.

RESULTS

After 8 weeks of either CPAP or exercise, no significant differences were observed in the levels of cell-free DNA, oxidative stress, and inflammation markers, except for an increase in AOPP and IL-17A levels in individuals who went through CPAP, which were higher when the CPAP device was used without the humidifier. We have also observed that CPAP significantly decreased the Pittsburgh scores and improved sleep efficiency and hours of sleep, while ESS scores remained unaffected.

CONCLUSIONS

Short-term treatment for OSA, be it CPAP therapy or moderate-intensity aerobic exercise, was not sufficient to alter either the oxidative stress and inflammatory profiles or the cell-free DNA levels of moderate to severe OSA patients. Short-term CPAP did, however, improve self-reported sleep quality.

An Overview of the Clinical Uses, Pharmacology, and Safety of Modafinil

Modafinil (MOD) is a wakefulness-inducing compound prescribed for treatment of excessive daytime sleepiness as a consequence of sleep disturbances such as shift work sleep disorder, obstructive sleep apnea, restless leg syndrome, or narcolepsy. While providing effective results in patients with sleepiness, MOD also produces positive outcomes in the management of fatigue associated with different conditions including depression, cancer, or tiredness in military personnel. Although there is clear evidence of the stimulant effects of MOD, current data also show that administration of this drug apparently induces positive neurobiological effects, such as improvement in memory. However, serious concerns have been raised since some reports have suggested MOD dependence. Taken together, these findings highlight the need to characterize the changes induced by MOD which have been observed in several neurobiological functions. Moreover, further work should follow up on the likely long-term effects of this drug if used for treatment of drowsiness and tiredness. Here, we review and summarize recent findings of the medical uses of MOD in the management of sleepiness and fatigue associated with depression or cancer as well as exhaustion in military personnel. We also discuss the available literature related with the cognitive enhancing properties of this stimulant, as well as what is known and unknown about MOD addiction.

The role of physical exercise in obstructive sleep apnea

Obstructive sleep apnea (OSA) is a common clinical condition, with a variable and underestimated prevalence. OSA is the main condition associated with secondary systemic arterial hypertension, as well as with atrial fibrillation, stroke, and coronary artery disease, greatly increasing cardiovascular morbidity and mortality. Treatment with continuous positive airway pressure is not tolerated by all OSA patients and is often not suitable in cases of mild OSA. Hence, alternative methods to treat OSA and its cardiovascular consequences are needed. In OSA patients, regular physical exercise has beneficial effects other than weight loss, although the mechanisms of those effects remain unclear. In this population, physiological adaptations due to physical exercise include increases in upper airway dilator muscle tone and in slow-wave sleep time; and decreases in fluid accumulation in the neck, systemic inflammatory response, and body weight. The major benefits of exercise programs for OSA patients include reducing the severity of the condition and daytime sleepiness, as well as increasing sleep efficiency and maximum oxygen consumption. There are few studies that evaluated the role of physical exercise alone for OSA treatment, and their protocols are quite diverse. However, aerobic exercise, alone or combined with resistance training, is a common point among the studies. In this review, the major studies and mechanisms involved in OSA treatment by means of physical exercise are presented. In addition to systemic clinical benefits provided by physical exercise, OSA patients involved in a regular, predominantly aerobic, exercise program have shown a reduction in disease severity and in daytime sleepiness, as well as an increase in sleep efficiency and in peak oxygen consumption, regardless of weight loss.

Zinc Is Indispensable in Exercise-Induced Cardioprotection against Intermittent Hypoxia-Induced Left Ventricular Function Impairment in Rats

In obstructive sleep apnea (OSA), recurrent obstruction of the upper airway leads to intermittent hypoxia (IH) during sleep, which can result in impairment of cardiac function. Although exercise can have beneficial effects against IH-induced cardiac dysfunction, the mechanism remains unclear. This study aimed to investigate the interactions of zinc and exercise on IH-triggered left ventricular dysfunction in a rat model that mimics IH in OSA patients. Nine-week-old male Sprague-Dawley rats were randomly assigned to either a control group (CON) or to a group receiving 10 weeks of exercise training (EXE). During weeks 9 and 10, half the rats in each group were subjected to IH for 8 h per day for 14 days (IHCON, IHEXE), whereas the remainder continued to breathe room air. Rats within each of the CON, IHCON, EXE, and IHEXE groups were further randomly assigned to receive intraperitoneal injections of either zinc chloride, the zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN), or injection vehicle only. IH induced a lower left ventricular fractional shortening, reduced ejection fraction, higher myocardial levels of inflammatory factors, increased levels oxidative stress, and lower levels of antioxidative capacity, all of which were abolished by zinc treatment. IHEXE rats exhibited higher levels of cardiac function and antioxidant capacity and lower levels of inflammatory factors and oxidative stress than IHCON rats; however, IHEXE rats receiving TPEN did not exhibit these better outcomes. In conclusion, zinc is required for protecting against IH-induced LV functional impairment and likely plays a critical role in exercise-induced cardioprotection by exerting a dual antioxidant and anti-inflammatory effect.

Structural equation modelling for the effect of physical exercise on excessive daytime sleepiness

OBJECTIVES

The present study aimed to examine the effect of physical exercise on excessive daytime sleepiness (EDS) which is a significant public health problem.

STUDY DESIGN

This is a population-based cohort study.

METHODS

We hypothesized that those who engage in regular exercise would have lower chances of dozing in the daytime and examined causal relationships between EDS and known risk factors for EDS using structural equation model (SEM).

RESULTS

We found that causal relationships from both depression and sleep quality to EDS were relatively weaker in those who regularly engage in physical exercise, which resulted in lower chances of having EDS.

CONCLUSION

Regular exercise may play a protective role in EDS prevention.

Assessment of the role of serum ischemia-modified albumin in obstructive sleep apnea in comparison with interleukin-6

OBJECTIVES

There is limited and contradictory information regarding the role of serum ischemia-modified albumin (IMA) in obstructive sleep apnea (OSA). In this study we examine the effects of OSA and obesity on IMA and interleukin-6 (IL-6), and detect whether IMA and IL-6 may be potential biomarkers in OSA.

METHODS

Fifty-one males who underwent all night polysomnography test were included into the study. Body-mass index (BMI) and apnea-hypopnea index (AHI) of all patients were determined. Serum IMA and IL-6 levels, erythrocyte sedimentation rate (ESR), complete blood count, routine blood biochemistry and thyroid function tests were performed.

RESULTS

Mean IMA [0.36 (± 0.04) U/ml, 0.89 (± 0.15) U/ml], mean IL-6 [1.01 (± 0.19) pg/ml, 2.02 (± 1.19) pg/ml] and mean ESR [4.14 (± 2.5) mm/h, 14.35 (± 13.7) mm/h] levels showed significant difference between non-OSA and OSA groups (P = 0.005, P < 0.001, P < 0.001, respectively). Sensitivity of IMA in distinction of non-OSA/OSA was equal to IL-6 and higher than ESR. IMA was also a stronger predictive factor than IL-6 and ESR in the evaluation of OSA groups (severe/mild/moderate OSA and non-OSA). IMA was the sole distinctive biomarker in assessment of obese and non-obese cases. IMA correlated with IL-6, AHI and ESR.

CONCLUSION

Serum IMA may be a valuable oxidative stress indicator for OSA and could act as a better biomarker than IL-6 for reflecting the presence and the severity of OSA.

Associations between longer habitual day napping and non-alcoholic fatty liver disease in an elderly Chinese population

Context

Both longer habitual day napping and Non-Alcoholic Fatty Liver Disease (NAFLD) are associated with diabetes and inflammation, but the association between day napping and NAFLD remains unexplored.

Objective

To investigate the association between the duration of habitual day napping and NAFLD in an elderly Chinese population and to gain insight into the role of inflammatory cytokines in this association.

Design and Setting

We conducted a series of cross-sectional studies of the community population in Chongqing, China, from 2011 to 2012.

Participants

Among 6998 participants aged 40 to 75 years, 6438 eligible participants were included in the first study and analyzed to observe the association between day napping duration and NAFLD. In a separate study, 80 non-nappers and 90 nappers were selected to identify the role of inflammatory cytokines in this association. Logistic regression models were used to examine the odds ratios (ORs) of day nap duration with NAFLD.

Results

Day nappers had a significantly higher prevalence of NAFLD (P<0.001). Longer day napping duration was associated in a dose-dependent manner with NAFLD (P trend <0.001). After adjustment for potential confounders, the ORs were 1.67 (95% CI 1.13–2.46) for those reporting 0.5–1 h and 1.49 (95% CI 1.01–2.19) for those reporting >1 h of day napping compared with individuals who did not take day naps (all P<0.05). Longer-duration day nappers had higher levels of IL-6 and progranulin (PGRN) but lower levels of Secreted frizzled-related protein-5 (SFRP5, all P trend <0.001). After adjusting for IL-6, PGRN, and SFRP5, the association between day napping duration and NAFLD disappeared (all P>0.05).

Conclusion

Longer day napping duration is associated with a higher prevalence of NAFLD, and inflammatory cytokines may be an essential link between day napping and NAFLD.

Sleep and exercise: a reciprocal issue?

Sleep and exercise influence each other through complex, bilateral interactions that involve multiple physiological and psychological pathways. Physical activity is usually considered as beneficial in aiding sleep although this link may be subject to multiple moderating factors such as sex, age, fitness level, sleep quality and the characteristics of the exercise (intensity, duration, time of day, environment). It is therefore vital to improve knowledge in fundamental physiology in order to understand the benefits of exercise on the quantity and quality of sleep in healthy subjects and patients. Conversely, sleep disturbances could also impair a person's cognitive performance or their capacity for exercise and increase the risk of exercise-induced injuries either during extreme and/or prolonged exercise or during team sports. This review aims to describe the reciprocal fundamental physiological effects linking sleep and exercise in order to improve the pertinent use of exercise in sleep medicine and prevent sleep disorders in sportsmen.

Physical activity and sedentary time in persons with obstructive sleep apnea and overweight enrolled in a randomized controlled trial for enhanced physical activity and healthy eating

BACKGROUND

The aim of the study was to describe the amount of physical activity and sedentary time in patients with obstructive sleep apnea syndrome (OSAS) and overweight and to explore potential disease-related and psychological correlates.

METHODS

A descriptive and correlational study was performed. Prospective data of physical activity and sedentary time were collected through accelerometry, and body mass index (BMI), daytime sleepiness, exercise self-efficacy, fear of movement, and depressive symptoms were measured at one point. Seventy-three participants with overweight (mean BMI, 35 kg/m(2) (5 SD)) and moderate/severe OSAS (apnea-hypopnea index ≥15) were consecutively recruited. Multivariate associations were determined through multiple linear regression analysis.

RESULTS

The participants took a daily average of 7,734 (3,528 SD) steps, spent an average of 77 min (54 SD) in moderate-to-vigorous physical activity (MVPA), and spent 11 h and 45 min (2 h and 8 min SD) sedentary. BMI, daytime sleepiness, exercise self-efficacy, fear of movement, and depressive symptoms did not explain variance in MVPA or steps but explained 22.9 % of variance in sedentary time. In backward selection analysis, BMI contributed to the explanatory degree of MVPA with 9 % whereas, fear of movement explained 6.3 % of the variance in steps and 14.3 % of the variance in sedentary time.

CONCLUSIONS

An important implication for future physical activity interventions is that both physical activity and sedentary behaviors should be targeted, and fear of movement may be an important determinant for change in patients with OSAS and overweight.