It is widely recognized that the death of a loved one commonly triggers intense sorrow and emotional pain. However, scientists have long known that there is more to grief than just sadness.

Bereaved individuals can experience a range of emotions, cognitions, and behaviors following loss. Typical grief reactions can range from short-term and mild to longer-term and severe.

When grieving does not naturally abate with time and the bereaved becomes stuck in a form of intensely distressing and impairing grief for more than one year following a loss, it is known as complicated grief.

In this article, we will briefly review current knowledge about the epidemiology, etiology, and treatment of complicated grief (CG).

What is Grief?

Seventy years ago, the psychiatrist Erich Lindemann, MD, PhD, performed a landmark investigation of the features of acute grief (Lindemann E, Am J Psychiatry 1944;101:141–148). He reported that bereaved individuals typically experience somatic distress, preoccupation with the deceased, guilt, social disconnection, and disrupted functioning. Each of these post-loss emotions, cognitions, and behaviors falls under the umbrella term of grief.

Since that study, scientists have more fully characterized the components of acute grief (Bonanno GA & Kaltman S, Clin Psychol Rev 2001;21(5):705–734). Typical grief-related emotions include dysphoria (eg, anger, irritability, hostility, fear, guilt), yearning for the deceased, and loneliness.

Common cognitive reactions include difficulty accepting the loss, preoccupation with thoughts about the deceased, a disrupted sense of identity, and uncertainty about the future. Grief-related behaviors can include social withdrawal and role disruption.

These emotions, cognitions, and behaviors typically do not represent psychopathology, as most people who are grieving have at least some of these experiences in the months following loss. However, individuals differ markedly in the intensity and severity of their acute grief responses (Bonanno GA et al, J Pers Soc Psychol 2002;83(5):1150–1164).

While reactions to loss are impacted by many factors, including the nature of the relationship with the deceased, the most common reaction following loss has been called “resilience,” which is characterized by a pattern of initially low grief symptoms that remain low over time (Bonanno GA et al, op.cit).

This finding is a sharp contrast to the long-held belief that people must fully experience substantial grief symptoms in order to “work through” their loss, and that those experiencing mild or transient grief symptoms were somehow pathological or at risk for delayed grief (Bonanno GA, Am Psychol 2004;59(1):20–28).

In fact, mild grief is one of many common and adaptive responses to loss. To be clear—even people displaying this “resilient” trajectory typically experience some yearning, emotional pain, and intrusive thoughts following a loss. However, for resilient individuals, these grief symptoms are usually mild and do not disrupt functioning.

In addition to the resilient trajectory of grief, a subset of people experience initially high levels of grief symptoms that decline naturally over time (Bonanno GA et al, op.cit). These individuals are said to be experiencing common grief. Those demonstrating this common grief trajectory typically have initially distressing and impairing levels of grief. However, their grief symptoms lessen progressively in the months following loss.

Finally, a small subset of bereaved individuals will experience severe, impairing grief symptoms that do not abate naturally over time, and instead become chronic. People experiencing this grief trajectory are said to be suffering from complicated grief. We use the term CG because it illustrates how the natural course of grief can stall as a result of complications, in the same way that a physical wound may fail to heal due to medical complications (Shear MK et al, Depress Anxiety 2011;28(2):103–117). Other terms that have been used include prolonged grief and traumatic grief.

When Grief Doesn’t Abate

CG is a disorder that occurs in some people who continue to experience high levels of grief symptoms for more than one year post-loss (although some definitions have used a time-frame of six months). CG occurs in approximately 7% of bereaved individuals and is more likely to occur following the loss of a child or a spouse (Kersting A et al, J Affect Disord 2011;131(1–3):339–343).

Women are more likely to develop CG than men, and the disorder is more common following an unexpected death than an expected death (Fujisawa D et al, J Affect Disord 2010;127(1–3):352–358).

CG is associated with significant morbidity, including increased rates of physical health problems and suicidal ideation (Prigerson HG et al, Am J Psychiatry 1997;154(5):616–623).

Grief researchers have proposed many explanations for why some people become stuck in a state of chronic grief. One theory is that the death of an attachment figure is a stressor that leads to a state of intense emotional longing or yearning for the deceased. Known as separation distress, this state is essentially acute grief (Shear MK et al, Eur Arch Psychiatry Clin Neurosci 2007;257(8):453–461).

For most bereaved individuals, this separation distress naturally subsides as they come to terms with the permanence of the loss and integrate the loss into their long-term memory. However, maladaptive coping strategies, such as persistent avoidance of reminders of the death, may prevent some people from fully acknowledging and/or integrating the loss.

For these individuals, the natural healing process is blocked and they remain stuck in a state of intense grief, as if the death just occurred, sometimes for years.

With the release of DSM-5 in 2013, the American Psychiatric Association has recognized CG, which it refers to as persistent complex bereavement disorder (PCBD).

Comorbidities and Differential Diagnosis

CG is one of several mental disorders that may arise following the loss of a loved one. For example, major depressive disorder (MDD) is more common among individuals who have lost a spouse than among married individuals (Zisook S & Shuchter SR, Am J Geriatr Psychiatry, 1993;1(4):316–326).

In the past, under DSM-IV-TR, clinicians were advised to not diagnose MDD in individuals within the first two months following the death of a loved one. However, this so-called “bereavement exclusion” was removed in DSM-5. In its place, there is a note that provides information to help clinicians distinguish acute grief from MDD.

In addition to MDD, people who are grieving also experience higher rates of panic disorder (PD) and generalized anxiety disorder (GAD) (Shear MK & Skritskaya NA, Curr Psychiatry Rep 2012;14(3):169–175). Posttraumatic stress disorder (PTSD) can also occur following loss, although prevalence rates vary depending on the cause of death. Clinicians should, therefore, consider both mood and anxiety disorders when making a differential diagnosis.

Many individuals with CG suffer from comorbid mental disorders. Approximately 55% of individuals with CG also have MDD, 49% have PTSD, 18% have GAD, and 14% have PD (Simon NM et al, Compr Psychiatry 2007;48(5):395–399). CG is also a risk factor for problematic alcohol use (Prigerson HG et al, op.cit).

Despite these high rates of comorbidity, CG is distinct from other mental disorders. Approximately 25% of people with CG do not suffer from a comorbid mood or anxiety disorder (Simon NM et al, op.cit). Furthermore, CG symptoms independently predict worse mental health and increased suicidal ideation, even when controlling for depression and anxiety symptoms (Boelen PA & Prigerson HG, Eur Arch Psychiatry Clin Neurosci 2007;257(8):444–452).

Comprehensive assessment and differential diagnosis for people who come to treatment for grief are especially important because misdiagnosis may result in incorrect treatment selection. For example, CG symptoms do not appear to respond optimally to some established treatments for MDD, such as use of the medication nortriptyline and interpersonal psychotherapy (Reynolds CF 3^rd et al, Am J Psychiatry 1999;156(2):202–208).

How to Treat CG

It is important to note that many grieving individuals don’t need treatment. Elevated grief symptoms typically reduce in severity and change in form naturally over time. However, people who are in enough distress to seek treatment should be carefully assessed and screened for suicidal ideation, mood and anxiety disorders, and CG (see Simon NM, JAMA 2013;310(4):416–423).

Empirically-supported psychotherapy is available for CG. A targeted 16-session psychotherapy called complicated grief treatment (CGT) has been demonstrated to be effective for approximately 50% of patients in a randomized controlled trial (Shear K et al, JAMA 2005; 293(21):2601–2608).

CGT includes psychoeducation about CG, telling and listening to the story of the death, exposure to reminders of the deceased, and goals work. Although CGT requires formal training to deliver, clinicians can use treatment strategies informed by this intervention.

For example, clinicians can use exposure therapy techniques to help patients reduce avoidance of people, places, and activities that remind them of their deceased loved ones (see Simon NM, JAMA, op.cit). This approach may have the added benefit of reducing patients’ social isolation and increasing their engagement in meaningful life activities.

Other forms of cognitive behavioral therapy (CBT), which includes both cognitive restructuring and exposure to reminders of the deceased, have been shown to be effective for 30%–50% of individuals with CG (Boelen PA et al, J Consult Clin Psychol 2007;75(2):277–284). Cognitive restructuring techniques used in this study included asking patients to identify and challenge maladaptive thoughts using worksheets. Exposure techniques included in vivo exposure to triggering people and places and imaginal exposure to distressing memories. The results of this study suggest that exposure therapy followed by cognitive restructuring is an effective treatment approach. Supportive counseling does not appear to be effective for CG (Boelen PA et al, op.cit).

Research on psychopharmacological treatments for CG is limited. There is some evidence from open-label, uncontrolled trials for the efficacy of two selective serotonin reuptake inhibitors (SSRIs): escitalopram (Lexapro) and paroxetine (Paxil) (see Simon NM, JAMA, op. cit). However, due to the lack of available data regarding the efficacy of these medications for CG, targeted psychotherapy (ie, CGT or CBT for grief) is recommended as the first line treatment.