Association of OCD with a History of Traumatic Events Among Patients in Methadone Maintenance Treatment

Einat Peles, PhD, Miriam Adelson MD, and Shaul Schreiber, MD

CNS Spectr. 2009;14(10):547-554

Faculty Affiliations and Disclosures

Dr. Peles is research director at the Dr. Miriam & Sheldon G. Adelson Clinic for Drug Abuse, Treatment & Research, Tel-Aviv Sourasky Medical Center & Sackler Faculty of Medicine, Tel Aviv University in Tel Aviv, Israel. Dr. Adelson is chairman of the Dr. Miriam & Sheldon G. Adelson Clinic for Drug Abuse. Dr. Schreiber is medical director at the Dr. Miriam & Sheldon G. Adelson Clinic for Drug Abuse.

Faculty Disclosures: The authors do not have an affiliation with or financial interest in any organization that might pose a conflict of interest.

Funding/Support: This research was supported by The Adelson Family Foundation.

Acknowledgements: The authors wish to thank Esther Eshkol for editorial assistance.


Introduction: We studied the relationship between obsessive-compulsive disorder (OCD) and lifetime history of any traumatic events among methadone maintenance treatment (MMT) patients.
Methods: In a cross-sectional sample of 167 patients, we clinically assessed for OCD using the Yale-Brown Obsessive Compulsive Scale and interviewed for their lifetime history of traumas.
Results: OCD was defined among 40.1% patients. Sixteen percent of patients reported having been victims of sexual abuse or rape, 21.6% had self-inflicted physical injuries, 34.1% attempted suicide, 44.9% sustained other physical violence or abuse, 28.7% were involved in a car accident as drivers and 6% as passengers, and 16.8% had significant falls. Patients with OCD compared with patients without OCD included more rape victims (28.4% vs. 9%), had more self-inflicted physical injuries (31.3% vs. 15%), and had more suicide attempts (46.3% vs. 26%), with no differences in other traumatic events exposure. The OCD group was characterized as being female (OR=4.0 [95% CI 1.7-9.3]), having a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text-Revision Axis I psychiatric disorder (OR=2.6 [95% CI 1.2-5.5]), being Israeli born (OR=2.9 [95% CI 1.2-6.9]), abusing benzodiazepines (OR=2.2 [95% CI 1.02-4.6]), having attempted suicide (OR=2.5 [95% CI 1.1-5.4]), and having longer duration of opiate abuse before admission to MMT (OR=1.06 [95% CI 1.01-1.1]).
Conclusion: Awareness of this profile and specific interventions are needed in order to identify and help patients at risk, especially in preventing additional suicide attempts. 


Obsessive-compulsive disorder (OCD) has been reported as being associated with alcoholism,1 along with nicotine dependence, and alcohol and sedatives abuse among women.2 Separately, individuals actively using both cocaine and marijuana were found to be at increased risk for OCD.3 Very few studies have been conducted on the prevalence of OCD and obsessive-compulsive symptoms (OCS) among drug addicts. A small, not representative study4 estimated the prevalence of OCD among a group of opioid addicts and patients in methadone maintenance therapy (MMT) as being 11%.

Peles and colleagues5 previously found high OCD rates among MMT patients. In this sample, OCD patients were characterized mostly as female and the most prevalent compulsion was cleaning rituals. These findings lead us to hypothesize that OCD and OCS may be relate to patients’ trauma history.

It is well established that having been victims of trauma is very common among drug addicts. Specifically, history of sexual abuse and rape, violence of any kind, repeated suicide attempts and self-inflicted injuries, and other kinds of trauma (such as involvement in traffic accidents and falls from heights) are also known to be associated with drug abuse and addiction.

We investigated the relationship between OCD and OCS and past trauma events, hypothesizing that the type of lifetime trauma exposure would be associated with OCD and OCS. Specifically, we hypothesized that a history of rape and sexual abuse would be most likely to be associated with OCD or OCS. We compared the OCD and non-OCD patients with respect to their lifetime trauma history as self reported when admitted to MMT as part of their routine intake by a structured trauma history questionnaire. 



The study was approved by the Tel Aviv Sourasky Medical Center Ethics (Helsinki) Committee (IRB number 07-111). The Adelson Clinic in Tel Aviv treats ~330 patients who meet criteria similar to those of the United States Federal Regulations for entering methadone treatment (ie, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text-Revision, criteria of dependence with multiple self-administrations of heroin per day for at least 1 year).

Characterization, demography, and effectiveness of the clinic have been reported elsewhere.6,7 We included 167 patients from a non-selective, random representative sample of 178 patients who were scored on the Yale-Brown Obsessive-Compulsive Scale for OCD and had available questionnaires about lifetime history of exposure to traumatic events. This questionnaire was done with each patient upon admittance to the MMT program between 2002–2006. However, since this questionnaire was added as part of the routine intake only in 2002, 11 of our 178 patients that had been admitted before 2002 did not have the questionnaires in their charts and were thus excluded from the study. A sample of 154 patients of the same 178 patients have already been studied for pathological gambling (PG).5

Urine Toxicology

Patients in MMT programs routinely undergo repeated observed urine tests throughout the entire length of their treatment. The drugs that were checked by enzyme immunoassay systems8 for abuse during the month prior to filling in the questionnaires for the current study included opiates, cocaine metabolite (benzoylecgonine), benzodiazepines (BDZs), amphetamines, cannabis, and methadone metabolite. The result was positive if at least one of the urine samples was positive. Drug abuse during the first month in MMT was also taken for analyses. Results were defined as “positive” if at least one of the urine samples was positive.

Obsessive-Complusive Disorder

The OCD questionnaire9 has been shown to have high validity10 and it accompanied the clinical interview. The 10-item scale is clinician-rated and each item is rated from 0 (no symptoms) to 4 (most severe symptoms), with separate subtotals for severity of obsessions and compulsions. Clinical OCD is defined by scores ranging from moderate to very severe (≥16). Patients with mild symptoms (not fulfilling DSM-IV-TR criteria for OCD) were defined as “pre-clinical (non-)OCD”. In addition, a random sample of patients defined as having “moderate OCD” was re-assessed by a blinded senior psychiatrist and all the diagnoses were confirmed.

Statistical Analyses

The SPSS 13 version was used. The OCD and non-OCD groups were compared by the chi2 or Fisher’s Exact test for categorical variables and by one-way analysis of variance in continuous variables (means±SD are presented). Since the proportion of patients with OCD differed significantly according to gender, a comparison between OCD by gender and each variable separately was done using logistic regression with OCD as a dependent variable and gender and other variables as independent variables. Multivariate analyses using a logistic regression model were done with OCD as a dependent variable and with all variables that were found to be significant (P<.05 for two tailed) in the univariate analyses as independent variables. Adequacy of the model was determined with the Contingency Hosmer and Lemeshow test11 (P=not significant).

Trauma History

As part of the routine intake on admission to MMT, patients are interviewed using a structured questionnaire about their trauma history. They are asked if they have history of any of the following traumas: sexual abuse, rape, suicide attempt, traffic accident, falls from heights, etc., as well as self-inflicted injuries, which we consider both a symptom and a trauma. For each trauma, patients were asked to provide dates, circumstances, and details, including the specification if it occurred before the initiation of drug abuse. In addition, drug abuse onset and the involvement of drugs and trauma events were taken were also taken from the Addiction Severity Index (ASI) modified questionnaire.


Patient Characteristics

Approximately 34% of patients were female. Mean age of opiate onset was 22.8±7.3 years and mean duration of opiate abuse before admission to MMT was 15.1±8.4 years. The mean age of the cohort at admission to MMT was 37.9±9.1 years. The mean duration in treatment was 5.6±4.2 years. The mean years of education was 9.9±2.2. Approximately 71.1% were born in Israel, and 48.5% had any axis I DSM-IV-TR psychiatric diagnosis, 22.2% treated with non-BDZs. In the month prior to the filling in of the OCD questionnaire, 61.7% patients abused any drug. Specifically, 52.7% had positive urine tests for BDZ, 13.2% for cannabis, 16.2% for opiates, 3% for amphetamines, and 11.4% for cocaine. On admission to MMT, in addition to positive urine for opiates, positive urine tests for cocaine were found in 24.1%, for cannabis in 10.2%, for amphetamines in 9%, and for benzodiazepines in 57.2%.

Definite OCD using DSM-IV-TR criteria was diagnosed in 40.1% subjects, while 31.7% patients had either no or very few OCS and 28.1% patients had mild OCS (defined as “pre-clinical OCD)­—all these 100 patients were defined as non-OCD. The sub-division of the 67 patients with definite OCD included 22.2% with moderate OCD, 13.8% with severe OCD, and 0.2% with very severe OCD.

Trauma History

Sixteen percent of patients reported of having been victims of sexual abuse or rape, 21.6% reported self-inflicted physical injuries, 34.1% reported attempting suicide, 44.9% reported having sustained other types of physical abuse or violence, 28.7% reported having been involved in a car accident as drivers and 6% as non-drivers, and 16.8% reported having had significant falls.

There were twice as many females in the OCD group compared to the non OCD group (49.3% vs. 24%, respectively, P=.001), and more were Israeli born (82.1% vs. 63.6%, P=.01). The OCD patients had a notably higher rate of BDZ abuse during the month prior to OCD questionnaire (68.2% vs. 43%, P=.002) with no difference on admission to MMT, no differences regarding other drug abuse (cocaine, opiates, cannabis, amphetamines) on both timings (data not shown), and a higher proportion of any DSM-IV-TR Axis I psychiatric disorder excluding obviously drug addiction and OCD (63.6% vs. 39%, P=.003), and use of psychotropics (31.3% vs. 16%, P=.04). The OCD patients had younger age of opiate onset (21.1±7.2 vs. 23.9±7.3, F=5.9, P=.02) and a trend of longer duration of opiate abuse before admission to MMT (16.6±8.6 vs. 14.1±8.1, F=3.6, P=.06), but no differences in the age of admission to MMT, the duration in MMT, and methadone dosages. Groups were also comparable in the years of education (Table 1).

Trauma history was more prevalent among OCD patients. Specifically, there were more rape victims (28.4% vs. 9%), self-inflicted physical injuries (31.3% vs. 15%), and history of suicide attempts (46.3% vs. 26%). There were no differences in the proportion of patients with sustained other physical abuse or violence, involvement in car accident, or significant falls between the OCD and non-OCD groups (Table 2).

OCD was twice as prevalent among females as in males, independent of all the above significant variables (gender P<.01 for all variables). After controlling for gender, OCD was still significantly associated with all the variables—younger age of opiate abuse onset, more years of opiate abuse before MMT admission, being Israeli born, abusing BDZs, having any DSM-IV-TR Axis I psychiatric diagnosis (other than drug addiction and OCD), being treated with psychotropics, having a history of self-inflicted physical injuries, and attempting suicide, but only with a trend towards having been the victim of sexual abuse or rape. Rape, however, was very rarely reported by males, and there were significantly more female rape victims (42.1% vs. 3.6% among males, P<.0005), with no gender differences in the other types of physical trauma.

There was a group of 19 patients who suffered both rape and suicide attempts. Females represented most of the “sexual abuse or rape only” category—88.9% and most of the combination of both rape and suicide attempts categories—84.2%, but they were a minority among the “suicide attempts only” category—18.4% (P<.0005).

The compulsive ritual most reported was cleaning in 29.4% of patients (42 with OCD and an additional 10 with OCS). As much as one-half of the 28 subjects with a history of sexual abuse or rape reported performing compulsive cleaning rituals, 17.9% had other types of compulsive rituals and 32.1% had none, compared with 24.6%, 7.2%, and 68.1%, respectively, among the 139 subjects who had no history of rape (P=.002).

Sequence of Traumatic Events and Drug Abuse

Of the 28 rape victims, 64.2% had been raped or sexually abused prior to the initiation of opiate and cocaine abuse. Thirty-six of the 64.3% subjects who attempted suicide did so after they had begun to abuse opiates/cocaine. The rape had occurred before the first suicide attempt in 15 of the 19 patients with a history of both experiences. The abuse of drugs followed the rape but preceded the suicide attempt in six of the same 15 patients, it followed both the rape and the suicide attempt in seven, and it preceded the rape in two. Of the four patients whose first traumatic event was attempting suicide, one was already abusing drugs and the other three started afterwards.

Multivariate analyses

The multivariate analyses (including all variables that were significantly associated with OCD in the univariate analyses) found that being female (OR=4.0 [95% CI 1.7-9.3]), having any Axis I psychiatric disorder beyond OCD and drug abuse (OR=2.6 [95% CI 1.2-5.5]), being Israeli born (OR=2.9 [95% CI 1.2-6.9]), abusing BDZs (OR=2.2 [95% CI 1.02-4.6]), having attempted suicide (OR=2.5 [95% CI 1.1-5.4]), and having longer duration of opiate abuse before admission to MMT (OR=1.06 [95% CI 1.01-1.1]) characterized our MMT patients who had concomitant OCD.

Logistic regression multivariate analyses for suicide attempt (with sexual abuse or rape, OCD, self-inflicted injury, and gender) found the history of rape as the only predictor for attempting suicide (this is in accordance with the finding that 67.9% of rape victims also had suicide attempts, and rape occurred before the first suicide attempt in 78.9% of those patients). Logistic regression multivariate analyses for each gender separately revealed that attempting suicide among females could be predicted by a history of rape (OR=5.3 [95% CI 1.4-20.5]), self-inflicted injury (OR=4.3 [95% CI 1.0-19.2]), and having OCD (OR=5 [95% CI 1.2-22.3]). None of these parameters served as predictors in males. 


The current study evaluated the relation between current OCD and OCS, and lifetime history of exposure to sexual and physical traumatic events among former heroin addicts, currently MMT patients. We found current OCD patients to be characterized with histories of rape, attempted suicides, and self-inflicted injuries. There was no relation between OCD or OCS and a history of physical violence, a trauma of falls, or of surviving a car accident. OCD patients were also characterized as being females, born in Israel, having any DSM-IV-TR Axis I psychiatric diagnosis (beyond drug abuse and OCD), younger age of opiate abuse onset, and BDZ abusers. Multivariate analyses revealed that in addition to the above mentioned characteristics, of the trauma types, only a history of suicide attempts was associated with OCD.

A very high rate of OCD (39.9%) was found among our patients (former heroin addicts currently in MMT) with the rate much higher among females (56.7%). This reflects the tendency of a higher prevalence of OCD symptoms found worldwide in the general population in females than in males (2.8% vs. 0.7%) as was shown in a cross-sectional nationwide epidemiological study of the Iranian population.12 In a representative sample of 4,075 adults from northern Germany, lifetime OCD was determined as being 0.5% with a female:male ratio of 5:7.13

Our finding of being Israeli born and not immigrants (most of our immigrant patients are from the former USSR) being independently associated with OCD and OCS was an unexpected and intriguing finding. Supporting this was an epidemiological study of psychiatric ethnic differences in Los Angeles, California that found lower OCD and other psychiatric disorders among Hispanics than Caucasians.14 On the other hand, a high rate of OCD was reported among Hawaiian and other Polynesian youth,15 which raises the possibility of genetic and environmental risk factors for OCD. In Israel, being Israeli-born could also appear to be related to the many obligatory cleansing rituals in orthodox Judaism that may resemble OCS,16 however, none of our patients spontaneously reported of such symptoms, nor did we directly ask about this issue.

Suffering from a concomitant diagnosis of any other DSM-IV-TR Axis I psychiatric disorder (beyond substance abuse and OCD) in most of our OCD defined patients is not surprising considering the features shared by some of them, especially anxiety disorders. Furthermore, compulsive behavior has much in common with addictive disorders. A central feature in both is the loss of control over behavior, which significantly impairs everyday functioning. However, there are many dissimilarities between the compulsive component of drug abuse and that of OCD.  More likely, they fall on a continuum, with the compulsivity associated with PG placed in-between them.5,17

Multivariate analyses of our MMT patient study of lifetime PG and current OCD characterized lifetime PG as more frequent in males (OR=3.6, 95% CI 1.5-8.8), with high obsessive score (OR=1.07, 95% CI 0.1-1.1) and older age on admission to MMT (≥40 years) (OR=2.4, 95% CI 1.1-5.0).5 We found BDZ abuse to be very prevalent among MMT patients and we have already reported that the BDZ abusers are characterized as suffering from high rates of depression,18 chronic pain,19 and sleep disturbances.20 We have also reported that reduction in BDZ abuse is associated with improvement of depression21 and sleep quality.22 It should be emphasized that BDZ was not prescribed but rather abused (much above the therapeutic upper level) among our MMT patients.

Of all types of trauma history, only suicide attempts was associated with OCD symptoms in multivariate analyses. These findings, however, were probably due to the statistical power, since only 16% of our sample were raped and 21.6% had self-inflicted physical injuries, while 34.1% had attempted suicide. However, suicide attempts  were associated with OCS, a history of being raped, and self-inflicted damage. The association between child/adolescent sexual abuse, incest and/or rape, borderline personality disorder, self-inflicted injuries and/or suicide attempts, body dysmorphic disorder, and eating disorders—and their association with higher prevalence in the female gender—have been the focus of research for decades,23-28 and elaborating on these issues is far beyond the scope of our present study.

The group of rape victims consisted mainly of females and the OCD subtype of symptoms was compulsive cleaning rituals. The symptom dimension of cleansing was recently reported to be more prevalent among women than men.29 Those authors reported the levels of contamination/cleaning anxieties to be higher in females. Although we did not find specific gender related differences, the individuals with a history of rape in our cohort were mostly females (however, one should keep in mind that males tend to report sexual assaults even less than women).

According to our study findings, suicide attempts were highly associated with OCD and having been a rape victim. Others have observed similar associations. Female gender was consistently found as being a risk for attempting suicide among drug abusers.30 Phillips and colleagues30 reported a higher suicide risk among depressed opiate-dependent female patients, who showed violent behavior both in the past 30 days and in their lifetime, and who had less education correlated with a history of suicide attempts. They also observed that family conflicts and depression severity correlated with current suicidal ideation. We did not find education level to be an associated factor.

Darke and colleagues31 studied 201 persons entering methadone/buprenorphine maintenance, 201 entering detoxification, 133 entering drug free residential rehabilitation, and 80 not in treatment. They found that the factors associated with recent suicide attempts were: being a residential rehabilitation entrant, female gender, younger age, less education, more extensive polydrug use, BZD abuse, recent heroin overdose, major depression, current suicidal ideation, borderline personality disorder, and posttraumatic stress disorder.

Roy32 reported that patients who had attempted suicide (N=175) were younger, female, had a family history of suicide, a lifetime history of major depression, were on antidepressant medication, had a history of alcoholism, had higher scores for childhood trauma, suffered from psychoticism, neuroticism and introversion, and had higher ASI psychiatric composite scores. Beautrais33 found that young females in Western countries are twice as likely as males to report suicidal ideation and exhibit attempted suicide behavior, although males are three- to four-fold more likely to die by suicide than females.

Female gender combined with younger age was found to be a risk factor in a review of epidemiologic studies of parasuicide (defined as suicide attempts and deliberate self-harm inflicted with no intent to die) in the general population.34 Chatham and colleagues35 matched 55 MMT patients with no suicidal attempts with 55 who had attempted suicide during treatment for gender and race/ethnicity: the latter had more psychological dysfunction (as evidenced by higher levels of depression, social dysfunction, hostility, risk-taking, and previous thoughts of suicide), less family support at the present time and during childhood, and more help-seeking behavior (as evidenced by self-referral, number of previous treatment episodes, attendance at self-help meetings, and higher scores on motivational measures of desire for help).

A history of rape was associated with suicide attempt for both genders in our study cohort. Interestingly, the females who attempted suicide were limited to those who were diagnosed as having OCD, while there was no relation between suicide attempts and OCD among the males. These findings are supported by a national comorbidity survey on the prevalence, risk factors, and social consequences of psychiatric disorders of 5,877 individuals in the US.36 The investigators showed that the odds of attempting suicide were 2- to 4-fold higher among drug abusing women but much higher (4- to 11-fold) among drug abusing men, compared with those who did not abuse, controlling for other adversities, and remained statistically significant after adjusting for lifetime psychiatric illnesses preceding suicide attempts. The study also reported that 79% of serious suicide attempts among women could be attributed to psychiatric disorders while 12% was attributable to rape and 7% to molestation.


Our findings demonstrate a clear association between OCD and a history of various types of physical trauma among patients in MMT. We were able to define a profile of the patients at highest risk for attempting suicide and so we call for heightened vigilance to prevent this behavior within the setting of MMT clinics. Our study was based on self reporting of physically traumatic events and sexual abuse that were not verified. We cannot rule out the possible effect of the drugs on their report, although we assume that partial report or no disclosure of past history of trauma exposure would be more associated with psychological mechanisms of denial or be too painful to discuss. Nevertheless, we may underestimate the amounts of trauma. However, this is a general limitation for all studies among MMT patients as well as other substance dependence populations. The extremely high rates of OCD and OCS in our patient’s population compared to the rates reported in the literature need to be confirmed by others. CNS


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