Sleep Apnea Treatments Research Paper
Obstructive sleep apnea syndrome is a disorder characterized by repeated episodes of upper airway occlusion, pauses in breathing or periods of generally shallow breathing during sleep. Respiratory disturbance in a sleeping person leads to a sharp deterioration in the quality of sleep. Headaches, excessive daytime sleepiness, irritability, decreased attention and memory, reduced potency – this is only part of the symptoms that a person may feel while chronically not getting enough sleep. Especially dangerous are acute attacks of drowsiness while driving, when one painfully wants to close the eyes and fall asleep for at least a few minutes. Affecting at least 4% of men and 2% of women (Wu et al., 2016), OSA is also associated with the extremely high economic losses that are close to those of diabetes: about $ 132 billion a year for the United States alone, including $ 15.9 billion a year in OSA-associated traffic accidents (Krishnaswamy et al., 2015). Sleep Apnea Treatments Research Paper
However, preservation treatments, such as the use of a dental device and the therapy of nasal continuous positive air pressure often demonstrate their ineffectiveness, due to the fact that they cause discomfort in patient and are not radical treatments in their core, which makes it necessary to search for new approaches to OSA treatment, including both a more technically acceptable implementation of CPAP therapy and its promotion, and the use of other methods. Further in this report, we will discuss the existing findings in the field of sleep apnea treatment as well as possible future directions for study.Sleep Apnea Treatments Research Paper
Literature review
Conservative approaches
For over 25 years, CPAP therapy has been a leading treatment for this disorder, in particular, due to its high medical and economic efficiency. CPAP involves slight “inflating” of the airways during sleep, preventing lowering pharyngeal soft tissue and removing the underlying mechanism of snoring. The treatment is carried out by a small compressor that delivers a constant airflow under certain pressure into the airway through a flexible tube and a sealed nasal mask. Initially, the procedure of choosing the treatment pressure is held in sleep laboratories. This figure remains fairly stable over months and years, provided that the person does not significantly change body weight. Subsequently, the patient uses the device at home. In severe cases, the device is to be used every night. A minor illness may require only periodical use of the device (4-5 times per week). In any case, as Patruno et al. (2014) mark, in spite of the clear positive effect on the cardiovascular, neurological and metabolic complications of OSA, the cessation of treatment in most cases causes resuming the initial breathing disturbances during sleep.
Moreover, the comparison of innovative alternatives to the regular treatment demonstrated that continuous positive airway pressure device (CPAP) was more effective than auto-adjusting positive pressure (APAP) in reducing arterial blood pressure as well as significantly affected insulin resistance. The retrospective analysis was assessing full-night polysomnographic studies of 26 patients, 19 of which were newly diagnosed with severe sleep apnea (Apnea-Hypopnea Index>30), and 7 of which were patients additionally suffering from obesity. The spectral and cross-spectral analyses of heart rate variability and respiration showed that sympathetic modulation was significantly higher in the group receiving APAP treatment, while the coherence values between HF oscillation and respiration were lower (Patruno et al., 2014). Besides, Patruno et al. (2014) found that explicit positive dynamics is only possible in case of elimination of the reasons for the development of the disease. Thus, in particular, the authors assume that if obesity is a major cause of OSA, the weight loss by 10% may ease the severity of OSA by 50%.
At the same time, several studies have shown that CPAP cannot completely restore the oxidant-antioxidant imbalance caused by repeated cycles of hypoxia (Wu et al., 2016). In search for solutions, Wu et al. (2016) came up to an idea that carbocysteine could be functionally the most effective antioxidant for reducing oxidative stress and sleep disordered breathing caused by OSA. The researchers observed 40 male patients aged 18-65 with moderate to severe OSA and randomly divided into two groups who either received 1500 mg carbocysteine daily or underwent nightly CPAP treatment. Eventually, both CPAP and carbocysteine treatment significantly and comparable effectively reduced the Epworth Sleepiness Scale score, plasma oxidative stress and plasma endothelial function parameters, AHI and oxygen desaturation. In addition, patient who received CPAP treatment demonstrated valuable increase in the mean oxygen saturation, while the OSAS group reported relieve from snoring after only 1-2 weeks of oral treatment. Sleep Apnea Treatments Research Paper
Invasive treatment
However, more effective treatments are currently associated with invasive methods. As Yonekura et al. (2003) and Wootten et al. (2014) state, surgical solutions include septoplasty, adenotonsillectomy, rhinoseptoplasty, sliding mandibula osteotomy, midline glossectomy, lingual tonsillectomy, nasal valve surgery, uvulopalatoplasty, inferior turbinotomy, etc. the therapeutic effect of these methods is the result of the conducted thermal or cold burn of the mucous membrane. Linear or point burns are made by the laser in the area of soft palate and uvula, causing their inflammation. During the tissue healing, it reduces in size and indurates, which reduces vibration and the sound of snoring phenomenon as such (Yonekura et al., 2003; Wootten et al, 2014).
Thus, in their study of 16 patients who underwent laser midline glossectomy, Yonekura et al. (2003) found that 75% demonstrated improvements in the desaturation rate and 50% showed the lowering of apnea-/hypopnea index. The majority of patients (aged 32-66) also showed significant improvements in symptoms such as snoring and daytime somnolence. The authors admit that LMG is linked to serious thermal injury and resulting postoperative edema. However, the observation of patients in 4 months after the surgery didn’t reveal postoperative bleeding or prolonged tongue pain (Yonekura et al., 2003). On the other hand, the study revealed that LMG is not helpful in cases with swollen lingual tonsils, and therefore 5 of 16 patients also had to undergo lingual tonsillectomy. The later demonstrated stable 50% of improvement in AHI and DR (Yonekura et al., 2003).Sleep Apnea Treatments Research Paper
In their turn, studying the outcomes of sleep endoscopy-directed treatments in children, Wootten et al. (2014) examined 31 children aged 5-18 with OSA, 26 of which underwent surgical treatment of ongoing upper airway obstruction. With the 51% rate of trisomy, operations were performed in the following frequencies: supraglottoplasty (2), uvulopalatoplasty (2), inferior turbinate submucosal resection (7), revision adenoidectomy (11), midline posterior glossectomy (MPG) (16), and lingual tonsillectomy (LT) (22). Uvulopalatopharyngoplasty and associated surgeries combine the principle of tissue removal in order to increase the lumen of the airways in the throat level (tonsils, palatal arch, and uvula). Overall, 92% of patients reported subjective improvement of nighttime sleep from 5.8 ± 2.9 before operation to 2.1 ± 2.5 after it (p<0.05), and daytime sleep accordingly from 2.1 ± 1.3 before to 0.6 ± 1.1 after the operation (p<0.05). Besides, according to Wootten et al. (2014), the criterion for success is a reduction in the index of respiratory disorders by 50% or more in 6-12 weeks after surgery.
And yet, as Krishnaswamy et al. (2015) rightly mark the best treatment is early prevention. In particular, the authors make an accent on the role of portable monitoring devices for diagnosing early symptoms of apnea that could be widely used in household on a regular basis. Having reviewed 125 studies published over the last decade, Krishnaswamy et al. (2015) mainly focused on 2 systematic reviews and meta-analysis, 3 guideline statements, 16 review articles, 16 randomized controlled trials, and 24 validation studies in order to identify the adaptability of portable monitor for clinical use. Overall, authors claim that portable monitoring devices
On the whole, authors list the following advantages of portable monitoring devices:
solve the problems of accessibility of sleep clinics and laboratories; prevent the need for intensive examining in cases of strongly suspected OSA; provide sleeping at home with comfort and convenience, which ensures less sleep disruption as well as offer reasonable option for limited mobility patients. Indeed, studies show that wide-ranging sleep evaluation along with the use of portable monitors can fulfill the uncovered need for diagnostic analysis in various out-of-hospital situations in patients with suspected OSA. Besides, as Krishnaswamy et al. (2015) note, wide introduction of portable devices will reduce costs and waiting time for sleep studies levels 1 and 2, which is particularly important for healthcare systems of developing countries with their poor resource basis.Sleep Apnea Treatments Research Paper
Discussion
Currently, CPAP is the most common method of treating severe forms of sleep apnea disease. Both Wu et al. (2016) and Patruno et al. (2014) found that classic CPAP stays to be more effective than its redesigned alternatives or oral medication substitutes. Indeed, the treatment has almost no side effects, but its effect lasts only when applied, as well as may be influence by body weight fluctuations. Patruno’s et al. (2014) idea to link CPAP effectiveness to obesity level is really impactful, but their sample was too small to measure it properly. Besides, longitude study is required in this regards. Meanwhile, as Wu et al. (2016) assumed, carbocysteine may be playing a major role in treating OSA patients with poor compliance with CPAP treatment. However, feasibility and efficiency of this procedure similarly requires additional assessment.
In turn, invasive treatments bring promise with their higher improvement rates and stable results. Here, Yonekura’s et al. (2003) report clearly demonstrates how laser surgeries could be effective for patients who poorly respond to other treatments, however the authors still didn’t elaborate on differences between LMG and LT long-term impacts. Similarly, Wootten et al. (2014) do not observe children throughout years after surgery, while it is a known fact that some tissues of the throat may grow back again in children under 7, which would lead to a relapse. From this perspective, Krishnaswamy’s et al. (2015) call to implement the wide clinical use of portable monitors may be relevant in term of early identification of symptoms in home conditions. However, the authors have not yet conducted their own research on portable monitors’ and the existing data needs validation.Sleep Apnea Treatments Research Paper
Conclusion
Obstructive sleep apnea is a vast public health problem characterized by the repetitive collapse of the upper airway occlusion during sleep. Various methods are used for the treatment of apnea: from lifestyle changes, diet and weight loss, to surgeries. Currently, the first-choice method for correcting sleeping condition is continuous positive airway pressure (CPAP) therapy. It is found to effectively reduce blood pressure and increase oxygen saturation, as well as is associated with lower AHI. Still more effective than other conservative measures, it surely also requires improvement. For instance, further research is required for understanding the role of autonomic cardiac regulation and obesity in CPAP long-term effects. Besides, alternative innovations that could make the second line of CPAP should be studied, like recent developments in Micro-CPAP Airing and nEPAP. Sleep Apnea Treatments Research Paper
On the other hand, it s hard to argue that invasive therapy, being riskier, is also a highly individualized, multilevel method, which stands for a radical, life-changing operation associated with the substantial improvement in key sleep indicators. With developing technologies, laser and endoscopy-directed treatments currently become less and less invasive and cause decreasing number of negative outcomes. In particular, further research may be directed at the effects of cryoplasty and somnoplasty, as well as nanorobotic treatments aimed at reducing post-surgery throat pain.
In general, there is a need for an assessment of innovative methods in randomized studies, including adequate titration and the effectiveness evidence with improved oxygenation, reduced drowsiness, increased daily activity, improved neurocognitive responses and mood, as well as the impact of new methods on the long course of OSA and its complications.Sleep Apnea Treatments Research Paper