DEAR EDITOR:

Trauma appears to be a specific psychosocial variable that potentially heightens an individual’s emotional response to the external environment. Although not everyone develops this syndrome in the aftermath of childhood trauma, perhaps the best example of this phenomenon is posttraumatic stress disorder (PTSD) and the subsequent clinical finding of hyperarousal.[1] Another example might be multiple chemical sensitivities (MCS), a controversial syndrome in which individuals experience adverse physical reactions to low levels of common chemicals.[2] Magill and Suruda[3] state that, “there are marked similarities between MCS and posttraumatic stress disorder.” In an effort to expand upon this trauma/hypersensitivity paradigm, we hypothesized that medications may represent an environmental element and that there might be a relationship between histories of childhood trauma (e.g., sexual, physical, and/or emotional abuses; witnessing violence; and physical neglect) and the number of patient-reported drug allergies. Indeed, in an earlier study, we determined that outpatients with borderline personality disorder, in which trauma is a contributory substrate, evidenced a marginal statistically significant relationship with the number of self-reported drug allergies.[4] However, in this latter study, we did not explore histories of trauma.

In the present study, participants consisted of 117 chronic noncancer pain patients (response rate: 94.4%; 43 men, 73 women) who were referred to a pain-management specialist by physicians predominantly in the areas of physical medicine and rehabilitation, orthopedics, and primary care. All participants were insured, and in this practice setting, 37 percent of patients are covered through workers compensation and 63 percent through private insurance (i.e., no Medicare or Medicaid sponsorship). We elected to examine this population because of the anticipated high frequency of childhood trauma. The sample ranged in age from 18 to 69 years (M=44.50, SD=11.50). With regard to race/ethnicity, 105 (89.7%) participants were Caucasian, six (5.7%) were Hispanic, three (2.6%) were African-American, one (0.8%) was Asian, and two (1.7%) were “other.” Sixty of the subjects were married (51.3%), 26 (22.2%) were never married, 26 (22.2%) were divorced, four (3.4%) were separated, and one (0.8%) was widowed. Nine (7.7%) did not graduate high school, 25 (21.4%) graduated high school only, 39 (33.3%) attended some college, 27 (23.1%) had college degrees, and 17 (14.5%) had graduate degrees.

Participants were recruited during their initial clinical evaluations for chronic pain. Each completed a research booklet that explored personal demographics, drug allergies (write-in section), and histories of childhood trauma. The definition of “drug allergy” was not provided. With regard to childhood trauma, participants were asked, “Prior to the age of 12, did you ever experience…” with yes/no response options regarding the following: sexual abuse (“any sexual activity against your will”); physical abuse (“any physical insult against you that would be considered inappropriate by either yourself or others and that left visible signs of damage on your body either temporarily or permanently or caused pain that persisted beyond the ‘punishment’”); emotional abuse (“verbal and nonverbal behaviors by another individual that were purposefully intended to hurt and control you, not kid or tease you”); physical neglect (“not having your basic life needs met”); and witnessing of violence (“the first-hand observation of violence that did not directly involve you”). Beyond face validity, this brief trauma assessment had no determined validity or reliability. We elected the preceding brief inquiry for childhood trauma because of our concerns about the possible negative impact of longer and more detailed surveys among chronic pain patients being seen in a busy clinic setting. The project was approved by an institutional review board and completion of the research booklet was assumed to function as informed consent (i.e., the first page of the booklet clearly stated that the results of this anonymous survey would be used in a study by the authors).

As for results, 33 (28.2%) participants reported having experienced sexual abuse, 35 (29.9%) physical abuse, 58 (49.6%) emotional abuse, 12 (10.3%) physical neglect, and 45 (38.5%) the witnessing of violence. Only 45 (38.5%) denied having experienced any of the five forms of trauma. Most (61; 52.1%) reported having experienced one, two, or three different types of childhood trauma.

All participants reported between 0 and 4 allergies to individual medications, with the exception of one participant who reported eight allergies. (To prevent this unusual outlier from exerting too much statistical influence, this patient’s number of allergies was recoded to 4.) Specifically, 74 participants reported no allergies, 25 one allergy, 12 two, 3 three, and 3 four. The overwhelming majority of allergies were attributed to antibiotics and analgesics. In the resulting analyses, the total number of allergies was positively correlated with the total number of different traumas indicated (r=0.19, p<0.05). In examining the specific types of childhood trauma, the total number of allergies statistically differed between the trauma and no-trauma groups for both witnessing violence and sexual abuse. Specifically, those who witnessed violence in childhood reported more allergies (M=0.84, SD=1.09) compared to those who did not witness violence ([M=0.44, SD=0.84], t[1,115]=-2.24, p<0.03). Similarly, those who experienced sexual abuse in childhood reported more allergies (M=0.91, SD=1.16) compared to those who did not experience sexual abuse ([M=0.48, SD=0.84], t[1,115]=-2.24, p<0.03.)

These data highlight a possible relationship between trauma and environmental sensitivity in the form of allergies to medications. We do not know if these reported allergies are genuine, exaggerated, adverse medication effects, or factitious. However, that specific environmental substances are less tolerated in  traumatized patients tends to reinforce the trauma/hypersensitivity paradigm observed in PTSD and MCS. If these findings are valid, then patients with multiple allergies to medications may be more likely to have histories of trauma with secondary sensitivity or reactivity to the environment in the form of drug allergies—an important finding for both psychiatrists and primary care physicians. In other words, multiple allergies may be a nonspecific clinical indicator of the possible presence of childhood trauma, and thereby alert clinicians to examine the patient’s history for evidence. In addition, such histories may culminate in a number of potential psychiatric and medical syndromes.

The potential limitations of this study include the small sample size, self-report nature of the data, the absence of a definition for “drug allergies” (i.e., a heightened risk of false positives), and the lack of a standardized assessment of childhood trauma. However, this is the first study to our knowledge to explore medication allergies and their specific relationship to childhood trauma in an outpatient, chronic-pain population. Our findings lend support to a trauma/hypersensitivity paradigm.

References
1.    American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Washington, DC: American Psychiatric Press, Inc., 1994.
2.    US Department of Labor Occupational Safety and Health Administration. Multiple chemical sensitivities. 2008. http://www.osha.gov/SLTC/multiplechemicalsensitivies/index/html. Accessed on November 25, 2008.
3.    Magill MK, Suruda A. Multiple chemical sensitivity syndrome. http://www.aafp.org/afp/980901ap/magill.html. Accessed on November 25, 2008.
4.    Sansone RA, Gentile J, Markert RJ. Drug allergies among patients with borderline personality symptomatology. Gen Hosp Psychiatry. 2000;22:289–293.

With regards,

Randy A. Sansone, MD

Professor, Psychiatry and Internal Medicine, Wright State University School of Medicine, Dayton, Ohio; Director, Psychiatry Education, Kettering Medical Center, Kettering, Ohio

J. David Sinclair, MD, FRCP
private practice, independent consultant for management of chronic non-cancer pain, Seattle, Washington

Michael W. Wiederman, PhD
Professor of Psychology, Department of Human Relations, Columbia College, Columbia, South Carolina