Here is a circle spoke diagram about the depression. Persistent sad, anxious, or “empty” mood, like feelings of hopelessness, or pessimism, irritability, feelings of guilt, worthlessness, or helplessness, and loss of interest or pleasure in hobbies and activities and etc. Depression is one of the most common mental disorders in the U.S. Depression can happen at any age, but often begins in adulthood. It can co-occur with other serious medical illnesses, such as diabetes, cancer, heart disease, and Parkinson's disease. Learn more details from this diagram now.