On the anniversary of traumatic events, some people may find that they experience an increase in distressing memories of the event. These memories may be triggered by reminders, but memories may also seem to come from out of the blue while at work, home, or doing recreational activities. An increase in distress around the anniversary of a traumatic event is commonly known as an "anniversary reaction" and can range from feeling mildly upset for a day or two to a more extreme reaction in which an individual experiences significant psychiatric or medical symptoms.

The September 11^th Anniversaries

One anniversary that is very likely to cause distress for years to come is the September 11 ^th anniversary. One reason is the sheer scope of the attacks. Over 3,000 people were killed in three locations and many more were affected by losing loved ones. The anniversary may also cause distress because it  receives widespread media attention. It is likely that the media will repeatedly show graphic images of the plane crashes and the towers collapsing. It is also likely that interviews with victims' families will be broadcast frequently.

A third reason this anniversary may cause distress is that it serves as a remembrance not only of the attacks themselves but also of the personal losses suffered by many. These losses include deaths, lifestyle changes, and financial losses. Lastly, the date itself may serve as a trigger for people. Never in history has an attack been labeled with the date on which it occurred. For all of these reasons, it is nearly impossible for any adult to go through the day unaware of its significance.

How people feel is based on a number of factors. Previous research suggests it is likely that people who were most affected or distressed by the September 11 ^th attacks will be the ones most upset by the anniversaries. Those directly exposed to the attacks or who lost loved ones will also tend to experience stronger anniversary reactions than the general population. Finally, people with PTSD and other mental-health problems will also probably have stronger reactions.

It is also possible that many people will continue to experience mild reactions to the anniversaries. People may have trouble sleeping or concentrating on the days surrounding the anniversary. Images may intrude on their lives or they may have memories of the attacks that make it difficult to work or relax.

A number of studies have provided an idea of the magnitude of the reactions. Following the original attacks, one study of 560 U.S. adults from across the country indicated that three to five days after the attacks, 90% of adults experienced at least one symptom of stress. These symptoms included nightmares, difficulty concentrating, trouble falling or staying asleep, and feeling upset by reminders or feeling irritable ¹ . Data from a later study of 2,273 adults assessed one to two months after the attacks suggested that the distress levels of adults across the country were within normal limits ² . Taken together, these findings suggest that on the anniversaries of the September 11th attacks, many people may experience at least a mild, normal increase in transitory distress.

Why do people experience anniversary reactions?

One theory about why anniversary reactions occur is based on the way traumatic experiences are represented in memory. According to Foa and Kozak ³ , traumatic memories contain specific information about the dangerousness of an event so that people will seek safety and protect themselves from similar harm. The memory provides information about what the individual should be afraid of, how he or she should perceive such situations, how to feel in that situation, and what to think.

For example, a traumatic memory of a rape might contain the information that it’s important to (1) be afraid of strange men at night, (2) run away if approached, (3) feel frightened, and (4) think one is in danger and needs help. An anniversary reaction can occur because the date of the original trauma (or some other trigger) activates a traumatic memory that produces strong emotions as well as physiological reactions, negative thoughts about the world, and protective coping responses.

What symptoms are associated with anniversary reactions?

A common type of anniversary reaction is experiencing grief and sadness around the anniversary of the death of someone significant. In fact, this is common enough that most major religions have commemorative ceremonies to support the intensification of grief at these times. At the extreme end of the spectrum, people can find themselves clinically depressed or even suicidal. However, for most, the episode of flattened affect and sadness is brief.

Symptoms of anniversary reactions to traumatic events can be understood as an exacerbation of the symptoms that define Posttraumatic Stress Disorder, or PTSD. These include re-experiencing symptoms, avoidance symptoms, and arousal symptoms.

• Re-experiencing

  Perhaps the most common reaction on the anniversary of a trauma is a reactivation of the feelings, physiological responses, and thoughts that occurred at the time of the event. For example, on the anniversary of a rape, a woman might feel frightened, nervous, and unsafe.

• Avoidance

  Another type of response associated with PTSD is the avoidance of trauma-related stimuli. Sometimes the feelings that are reactivated by the anniversary are so strong that people try to avoid situations, places, or people that are connected to the event. For example, a combat veteran may choose to stay home on veteran's day and avoid parades, veterans, and other reminders.

• Arousal

  A third kind of reaction is to feel nervous and on edge. The reactivation of the traumatic memory might be so intense that it is difficult to sleep or concentrate. Some people become more irritable and jumpy and others feel like they have to be more on guard. Thus, motor vehicle accident survivors might not be able to get in a car on the anniversary of their severe accidents because they are too angry or fearful that they will be hit again.

Other types of anniversary reactions may involve anxiety problems such as panic, specific fears, or worry. Individuals may have panic attacks, be afraid to go certain places, or find that they worry about their safety and the safety of their loved ones. Others may experience physical (or medical) symptoms such as fatigue and pain or general health complaints such as headaches and stomachaches.

What becomes obvious is that there is not one classic anniversary reaction. How the anniversary reaction presents itself will differ for different people. It may depend on the type of traumatic experience, on the time since the original trauma or loss, on the characteristics of the individual, or other factors.

Are there any empirical studies of anniversary reactions?

There are few empirical studies of anniversary reactions. In one study, 92 widows and widowers were interviewed on the first anniversary of their spouse's death. Four of the participants reported clinically significant depression that they connected to the anniversary date ⁴ . In a series of studies, Morgan and colleagues examined anniversary reactions in Gulf War veterans two and six years after the end of the Gulf War ^{5, 6}. The researchers asked the veterans and their wives to identify the veteran’s worst month of functioning in the past year. When the researchers compared the worst month identified to previously identified dates of traumatic events that occurred during the Gulf War, they found that 38% of participants reported that their worst month coincided with the month in which their trauma occurred ⁵ . Veterans with these anniversary reactions had significantly more PTSD symptoms than veterans who did not have anniversary reactions, and all of the veterans who met criteria for a diagnosis of PTSD had anniversary reactions ⁵ . Finally, one study was done examining patterns of hospital admissions in patients with seasonal mood disorders ⁷ . Based on chart reviews, 4 out of 41 patients with multiple hospital admissions over a seven-year period exhibited depressive or manic episodes that coincided with the time of a past traumatic event.

What can one do to feel better?

Most people will feel better within a week or two after the anniversary. Over time, the stress symptoms will decrease in both frequency and severity. People may find it helpful to make specific plans for the anniversary day so that they have other things to occupy their time besides memories of the event. Some may choose to participate in a commemorative ceremony such as visiting a grave, making a charitable donation, giving blood, helping others, or dedicating the day to spending time with family.

For those individuals for whom the stress response continues to persist, good help is available. Individuals should contact primary care providers or mental-health professionals to seek support if needed. It is common for people who did not seek help for the original trauma to feel ashamed that they are still suffering months or years later. However, the fact that someone did not seek help may itself be symptomatic of trauma-related avoidant behaviors and can be viewed as a signal that professional help should be sought.

References

1. Schuster, M.A., Stein, B.D., Jaycox, L.H., Collins, R.L., Marshall, G.N., Elliott, M.N., Zhou, A.J., Kanouse, D.E., Morrison, J.L., & Berry, S.H. (2001). A national survey of stress reactions after the September 11, 2001 terrorist attacks. New England Journal of Medicine, 345, 1507-1511.

2. Schlenger, W.E., Caddell, J.M., Ebert, L., Jordan, B.K., Rourke, K.M., Wilson, D., Thalji, L., Dennis, J.M., Fairbank, J.A., & Kulka, R.A. (2002). Psychological reactions to terrorist attacks: Findings from the national study of Americans' reactions to September 11. Journal of the American Medical Association, 288, 581-588.

3. Foa, E., & Kozak. M. (1986). Emotional processing of fear: Exposure to corrective information. Psychological Bulletin, 99, 20-35.

4. Borstein, P.E. & Clayton, P.J. (1972). The anniversary reaction. Diseases of the Nervous System, 33, 470-472.

7. Beratis, S., Gourzis, P., & Gabriel, J. (1996). Psychological factors in the development of mood disorders with a seasonal pattern. Psychopathology, 29(6), 331-339.