mrcem2-0460

A 45-year-old man with a long-standing history of mental health issues, including bipolar disorder and anxiety, comes in alone expressing worries about his memory. He reports struggling to recall where he has placed items around his home and occasionally forgetting the names of his acquaintances. This onset occurred abruptly one week ago, and he emphasizes the significant impact it is having on his daily life.

What is the SINGLE most probable diagnosis?