A 42-year-old married man with a 10-year history of bipolar disorder type I presents to the emergency department following a suicide attempt by pesticide ingestion. His wife reports that over the past 3 months he has experienced depressive episodes alternating with brief hypomanic periods. He lost his job 2 weeks ago and has been increasingly withdrawn. On examination, he appears disheveled, with poor eye contact. He admits to persistent suicidal ideation and states, "I have a plan—I will hang myself tonight if I leave this hospital." He has two previous suicide attempts (one 5 years ago, one 8 years ago), both by overdose. His father died by suicide when the patient was 16 years old. Which of the following is the MOST significant risk factor for completed suicide in this patient?