Abstract
In this chapter, Ms. P, a 63yearold married woman, seeks psychiatric evaluation due to a recent diagnosis of rheumatoid arthritis. She initially presented with physical symptoms including fatigue and hand pain, which improved with treatment but were followed by escalating worries about her job performance. Despite not reporting a depressed mood, Ms. P exhibits signs of depression, including anhedonia and changes in appetite and sleep. Her anxiety, especially related to her medical condition and prognosis, hinders her daily life and medical followups. This chapter emphasizes the comorbidity of anxiety and depression, which often goes undiagnosed, and highlights the need for skilled clinicians to distinguish between the two. It discusses the genetic basis and risk factors for comorbid anxiety and depression, underlining the importance of obtaining a detailed patient history and evaluating the impact of symptoms on daily functioning. Treatment involves a multimodal approach, including psychotherapy and pharmacotherapy.