Sometimes, however, depressive emotional patterns are deeper and recur over time. Depression occurs most often in women and the elderly. In the classical model, it takes place in episodes limited in time, but with a tendency to recur. There may be a pattern of mood swings and cycling, particularly in bipolar disorder, but if mood swings are always downward without clear evidence of mania, this diagnosis is not made. Many people show a long-term pattern of dysfunction, with variable but persistent symptoms of discontent, poor sleep, regression, withdrawal, lack of pleasure, low mood and even hopelessness or despair.
Genetic factors predispose some individuals to chronic depression.
Personality patterns also can lead to chronic intercurrent depression, due to poor social skills, lack of rewards in life, social isolation and obsessive-compulsive or avoidant character patterns. John seems to fit this pattern, with compulsive work habits, social isolation and recurrent symptoms. He also shows impaired performance on the job, with difficulty concentrating and keeping up. These short-term problems are superimposed on his solitary, unsatisfying lifestyle. His past may hold interpersonal disappointments or childhood trauma, with a possible history of divorce in his family.