الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 186 |  |  |
| | | from | 186 | | |
Abstract
Obstructive sleep apnea (OSA) is a common breathing disorder characterized by repetitive narrowing and closure of the upper airway (UA) during sleep. It is associated with major adverse health outcomes as well as increased cardiovascular diseases, neuro-cognitive dysfunction, and metabolic disorders.
This is an observational case control study conducted on 90 subjects (45 patients with confirmed polysomnographic OSA, 23 obese participants and 22 non obese healthy participants) that attended outpatient chest clinic and inpatient at cardiothoracic hospital during the period between January 2019 and January 2020.
Written informed consent was obtained for those invited and agreed to participate in this study.
This study aimed to determine the role of submental ultrasonography; tongue base thickness (TBT), retrolingual diameter (RLD), and the distance between 2 lingual arteries (DLA) in diagnosing and determining severity of OSA. To look for wither OSA is associated with liver affection evaluated by fibro-scan and identification of the relation between severity of OSA and liver affection if present. To look for if OSA is associated with atherosclerosis by evaluating the carotid artery stiffness and detecting relation between severity of OSA and carotid artery stiffness if present.
All participants in this study (patient group and control healthy group) were subjected to: full history taking, sleep questionnaires (STOP- BANG, epworth sleepiness scale), spirometry, clinical examination, laboratory investigations (CBC, RFT, LFT, RBS, ABG, thyroid function, and lipid profile), submental ultrasonography (TBT, RLD, and DLA), carotid artery stiffness, liver elastography, and echocardiography.
Our study revealed that the prevalence of hypertension, diabetes mellitus, and pulmonary artery systolic pressure were higher in OSA patients more than control obese and non-obese subjects.
We found that epworth sleepiness scale was important in helping diagnosis of OSA. It showed a significant change among OSA patients and control obese and non-obese. Epworth sleepiness scale also increased with the severity of OSA.
STOP BANG questionnaire revealed a significant increase among OSA patients more than control obese and non-obese subjects.
Our study confirmed that DLA increased in OSA patients. With sensitivity 77.78% & specificity 80% at cutoff point 33.1mm in diagnosing OSA. Also; we found that DLA increased with the severity of OSA. With sensitivity 88% & specificity 55% at cutoff point >34mm in identifying sever OSA. We also found that there was positive correlation between DLA and AHI in the studied OSA patients.
In the present study we found that RLD had significant decrease among OSA patients. With sensitivity 86.67% & specificity 80% at cutoff point ≤ 29.5mm in diagnosing OSA. There was also decrease in the RLD with increase severity of OSA but with non-significant manner. And negative correlation between RLD and AHI in the studied OSA patients.
We found that TBT showed statistically significant increase in OSA patients. At cutoff point >42mm, TBT has 86.67% sensitivity & 84.44% specificity in diagnosing OSA. We also found statistically significant increase in TBT with increase severity of OSA. And at cutoff point >45.3mm, TBT has 88% sensitivity & 55% specificity in detecting severe OSA. And we found positive correlation between TBT and AHI in the studied OSA patients.
Our study showed statistically significant increase in carotid artery stiffness among patients with OSA. We also found statistically significant increase in carotid arteries stiffness with increase severity of OSA. At cutoff point >6.23m/s, carotid arteries stiffness has 80% sensitivity & 75% specificity in detecting sever OSA. And we found positive correlation between carotid arteries stiffness and AHI in the studied OSA patients.
In our study we found no significant difference regarding the serum level of ALT and AST between OSA patients and healthy control subjects. Also AST and ALT level were not significantly different among OSA patients with different level of severity.
Our study revealed that the assessment of liver stiffness measurement (LSM) by fibro scan showed statistically significant increase among patients with OSA compared with control healthy subjects.
We found also that LSM increased with increase severity of OSA. At cutoff point >1.46cm.sec, LSM has 68% sensitivity & 80% specificity in detecting sever OSA. In the present study; we found positive correlation between LSM and AHI in the studied OSA patients.
According to Metavir score in staging of liver fibrosis; in our study liver fibrosis is more among OSA patients than control obese and non-obese subjects.
We found that 62.2% of the OSA patients had mild – moderate fibrosis, while; 31.1% of them had normal – mild fibrosis, and 6.7% had normal liver.
Conclusion
According to the results of our study, it could be concluded that:
1. Submental ultrasonography (tongue base thickness, retro lingual diameter, and distance between 2 lingual arteries) is noninvasive, convenient, and effective tools in helping diagnosis and assessing the severity of OSA.
2. Liver affection is common in OSA patients and can be assessed by liver stiffness measurement using fibro-scan while liver enzymes are normal.
3. Atherosclerosis is common in OSA patients and can be early assessed by ultrasonography imaging of the carotid artery and measuring the carotid artery stiffness.