This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cystic fibrosis & Sleep apnea, Subject name: Medicine
Obstructive sleep apnea may result in all of the following except? 
Select and explain. 
A. Systemic hypeension, B. Pulmonary hypeension, C. Hea block, D. Impotence
C: Hea block
Answer: C: Hea block 
Explanation: OSAHS raises 24-hour mean blood pressure. The increase is greater in those with recurrent nocturnal hypoxemia and is at least 4-5 mmHg. The resultant hypoxia also leads to pulmonary aery constriction leading to PAH. Other effects of OSAHS- Personality and mood changes, depression and anxiety, sexual dysfunction- impotence and decreased libido, gastroesophageal reflux. Atrial fibrillation and stroke are also repoed.