MRCP2-0613

MRCP2-0613

You are requested to assess a 75-year-old man who reports difficulty maintaining his erection during sexual activity for the past two months. He has a medical history of a psychiatric condition, which is being treated with lithium, type 2 diabetes diagnosed three years ago, managed with metformin and diet, and angina, for which atenolol was recently prescribed, along with ACE-inhibition for blood pressure and renoprotection. His blood pressure is 145/85 mmHg, and his recent HbA1c was 75.96 mmol/mol (9.1%). What is the most probable cause of his declining sexual function in the last two months?