BOSTON, MA — Sometimes, after the loss of a loved one, symptoms of grief linger and become increasingly debilitating. This condition, called complicated grief, has features of both depression and post-traumatic stress disorder (PTSD). And there is some evidence that a distinct type of treatment may bring relief, reports the October issue of the Harvard Mental Health Letter.

The most characteristic symptoms of complicated grief are intrusive thoughts of the deceased person and a painful yearning for his or her presence. When grief is most severe, a person may deny the death or consider suicide.

The risk of developing complicated grief depends on both the immediate circumstances of the death and the background against which it occurs. Complicated grief is more likely to occur if the death was sudden, violent, or unexpected. But just as experiences not typically regarded as traumatic can still lead to PTSD symptoms, so can even normal bereavement produce complicated grief.

"Whether complicated grief occurs depends on how the person copes, not just with trauma, but with loss," says Dr. Michael Miller, editor in chief of the Harvard Mental Health Letter. "If a person could not respond to earlier losses without losing emotional equilibrium, complicated grief becomes a greater danger for him or her."

Treatment of complicated grief often relies on the idea that grieving is an experience to be worked through. A promising treatment called traumatic grief therapy uses cognitive behavioral methods for symptoms and stress relief, along with interpersonal techniques to encourage re-engagement with the world.