<s>[INST] context: In obstructive sleep apnea, airway obstruction results in snoring as well as failure to breathe during the night. The resulting anoxia causes frequent awakenings during the night so that the patient feels tired in the morning. Decreased oxygen availability may result in leg edema, hypeension, morning headaches, cardiac arrhythmias, and stroke in patients with obstructive sleep apnea. myocardial infarction by 50% to 75% within 5 years of cessation. The reduced risk for the other therapies are as follows: *Postmenopausal estrogen replacement has a 44% decreased risk * Mild to moderate alcohol consumption has a 25% to 45% decreased risk * Exercise has a 45% decreased risk. *Prophylactic low dose aspirin has a 33% decreased risk, paicularly in the incidenc of the first acute myocardial infarction in middle aged men and women; however, there is no reduction in overall total cardiovascular moality. Patients over 50 years of age with risk factors for coronary aery disease are the group most likely to benefit, it is not good for prophylaxis if the patient has poorly controlled hypeension, because there is a danger for a hemorrhagic stroke. [/INST] question: A 45 year old male patient complains that he is often tired and has a headache almost every morning His wife says that her sleep is disturbed because of the patient's loud snoring. Physical examination reveals leg edema. Hypeension, and cardiac arrhythmia. From which disorder is this patient most likely suffering? | options: A: Sleep wake schedule disorder B: Obstructive sleep apnea C: Narcolepsy D: Delayed sleep phase syndrome | answer: B </s>