Childhood adversities as specific contributors to the co-occurrence of posttraumatic stress and alcohol use disorders☆
Introduction
The DSM-IV defines posttraumatic stress disorder (PTSD) as a psychological reaction following exposure to a traumatic event characterized by symptoms of re-experiencing, avoidance and increased arousal for at least one month (American Psychiatric Association, 1994). PTSD is frequently associated with a considerable amount of comorbid conditions and suicidality (Galatzer-Levy et al., 2013, Müller et al., 2014). Previous research suggests that the course and clinical profile of PTSD might be especially complicated by comorbid alcohol use disorders (AUD) (Carter et al., 2011, Saladin et al., 1995). Indeed, the co-occurrence of PTSD and AUD is well documented by a number of studies (for a review Debell et al., 2014; Stewart et al., 1998). The prevalence of AUD in individuals with PTSD was estimated from 10% in a community sample up to 61% in Vietnam veterans (Debell et al., 2014). In the general population PTSD, defined according to the DSM-IV, was the anxiety disorder that was most strongly associated with AUD (Leray et al., 2011, Norman et al., 2012). Although the epidemiological prevalence of PTSD/AUD is rather low compared to other co-occurring common mental disorders, this condition has been associated with some of the poorest treatment outcomes, a higher number of comorbid psychiatric conditions, functional impairment as well as lower quality of life (Blanco et al., 2013, Sartor et al., 2010).
The awareness of the negative consequences of co-occurring PTSD and AUD has led to a sizeable amount of research on its etiology in order to develop appropriate prevention and treatment strategies (Pennington et al., 2014, Schaumberg et al., 2015). Thereby, some research has focused on the role of adverse environmental factors in the etiology and functional association of these conditions (Maniglio, 2012, Norman et al., 2012, Stewart et al., 1998). Epidemiological data suggest that approximately three quarters of individuals with AUD have experienced at least one traumatic event during their lives (Mills et al., 2006).
There is evidence that certain trauma types, specifically childhood traumatic experiences, are outstanding determinants in the development of AUD in individuals with PTSD (Khoury et al., 2010). From those, sexual abuse appeared to be the most specific risk factor for a PTSD/AUD comorbidity in clinical as well as epidemiological samples (Langeland et al., 2004, Sartor et al., 2010). A recent epidemiological study also found that other adverse environmental factors during childhood, which refer to familial dysfunction such as parental mental health problems or familial instability, were more likely in individuals with PTSD and AUD than in those with PTSD alone (Blanco et al., 2013). Even although these findings are based on bi-variate associations, they raise an interesting point since no other data on this topic are currently available. Previous research has shown that adversities in childhood, such as unstable family structures, parental mental health and overall unhappy childhood increase the risk for both PTSD (Peleikis et al., 2004) and AUD (Kauhanen et al., 2011, Kestila et al., 2008), independently from adversities experienced during adulthood. However, it is not well known whether childhood adversities constitute a unique risk in comorbid cases (PTSD/AUD) after accounting for background variables such as sociodemographic and clinical factors. Accordingly, a number of individual level determinants that were found to be associated with an increased risk of having both PTSD and AUD have been taken into account. These factors comprise male gender, older age, lower educational attainment and lower socio-economic status, or having more psychiatric comorbidities including other substance use disorders and suicide attempts (Blanco et al., 2013, Leeies et al., 2010, Sonne et al., 2003).
While most research on the comorbidity of PTSD/AUD focused on clinical samples the current study provides the opportunity to examine environmental factors associated with this condition in a community sample. Notably, relatively few epidemiological data on trauma and PTSD are available for Switzerland (Hepp et al., 2006, Perrin et al., 2014). Compared to most other Western countries, Switzerland is a relatively secure environment with rather low rates of trauma exposure (Hepp et al., 2006, Perrin et al., 2014). On the other hand there were quite high rates of PTSD in the current sample compared to other populations with similar or even higher rates of exposure (Kawakami et al., 2014, Müller et al., 2014, Olaya et al., 2014), which makes this sample somewhat unique in the general population.
The current study aims to examine how trauma characteristics (type and age of trauma), and other environmental adversities that occurred during childhood (dysfunctional familial environment) are related to comorbid AUD in our community sample of individuals with PTSD. First, we hypothesized that sexual abuse would be more likely in the comorbid condition group than in the group with PTSD alone while we expected no such associations for other trauma types. Second, we expected trauma exposure below the age of 16, in particular sexual abuse, to be more strongly related to the comorbid condition than to PTSD alone. We also expected the comorbid group to report a younger recalled age of exposure to sexual trauma in particular than the group with PTSD alone. Finally, we sought to replicate earlier preliminary findings of high associations between childhood environmental adversities and comorbid PTSD/AUD. Thus, we hypothesized that the comorbid group were more likely to have experienced an adverse childhood environment than the group with PTSD alone.
Section snippets
Sample and procedure
All data were collected within the PsyCoLaus study, a subsample from the larger CoLaus study, a randomly selected population-based cohort study in Lausanne, i.e. in the French-speaking part of Switzerland. From 2003 to 2006, a community sample of N=6734 subjects aged between 35 and 75 years was recruited for the first wave of CoLaus, an epidemiological study designed to assess the prevalence of cardiovascular risk factors and diseases. From a total of 5,535 individuals that finally participated
Results
Table 1 shows the distribution of socio-demographic and clinical variables for the total sample and the subsamples of subjects with PTSD/AUD (17.14%) and PTSD alone (82.86%), respectively. The comorbid group did not differ from those with PTSD alone regarding any socio-demographic characteristics. However, compared to PTSD alone, comorbid PTSD/AUD was associated with higher rates of antisocial personality disorder, other substance-related disorders, lifetime suicide attempts as well as with a
Discussion
The present study aimed to examine environmental factors that potentially contribute to the development of comorbid AUD in subjects with pre-existing PTSD. For this analysis, individuals with a lifetime diagnosis of PTSD were chosen from a large representative sample from the Swiss community. Lifetime and childhood traumatic events as well as markers of adverse or dysfunctional childhood environments were examined for their association with the development of AUD.
As expected, our results
References (44)
- et al.
Diagnostic interview for genetic studies (DIGS): inter-rater and test–retest reliability of alcohol and drug diagnoses
Drug Alcohol Depend.
(2002) - et al.
Comorbidity of posttraumatic stress disorder with alcohol dependence among US adults: results from National Epidemiological Survey on Alcohol and Related Conditions
Drug Alcohol Depend.
(2013) - et al.
Relapse to alcohol and drug use among individuals diagnosed with co-occurring mental health and substance use disorders: a review
Clin. Psychol. Rev.
(2006) - et al.
Substance use disorder-PTSD comorbidity. Patients' perceptions of symptom interplay and treatment issues
J. Subst. Abuse Treat.
(1998) - et al.
PTSD symptom clusters in relationship to alcohol misuse among Iraq and Afghanistan war veterans seeking post-deployment VA health care
Addict. Behav.
(2010) - et al.
Trauma and posttraumatic stress disorder in Japan: results from the World Mental Health Japan Survey
J. Psychiatr. Res.
(2014) - et al.
Prevalence, characteristics and comorbidities of anxiety disorders in France: results from the “Mental Health in General Population” survey (MHGP)
Eur. Psychiatry
(2011) - et al.
Factors associated with comorbidity patterns in full and partial PTSD: Findings from the PsyCoLaus study
Compr. Psychiatry
(2014) - et al.
Review of biological mechanisms and pharmacological treatments of comorbid PTSD and substance use disorder
Neuropharmacology
(2012) - et al.
Characteristics of posttraumatic stress disorder-alcohol abuse comorbidity in women
J. Subst. Abuse
(1996)
The relative influence of childhood sexual abuse and other family background risk factors on adult adversities in female outpatients treated for anxiety disorders and depression
Child Abuse Negl.
A preliminary examination of cortical neurotransmitter levels associated with heavy drinking in posttraumatic stress disorder
Psychiatry Res.
Understanding comorbidity between PTSD and substance use disorders: two preliminary investigations
Addict. Behav.
PTSD-related alcohol expectancies and impulsivity interact to predict alcohol use severity in a substance dependent sample with PTSD
Addict. Behav.
Functional associations among trauma, PTSD, and substance-related disorders
Addict. Behav.
Diagnostic and Statistical Manual of Mental Disorders
Co-occurring posttraumatic stress disorder and alcohol use disorders in veteran populations
J. Dual Diagn.
A systematic review of the comorbidity between PTSD and alcohol misuse
Soc. Psychiatry Psychiatr. Epidemiol.
Childhood maltreatment and the risk of substance problems in later life
Health Soc. Care Community
A diagnostic interview: the schedule for affective disorders and schizophrenia
Arch. Gen. Psychiatry
Patterns of lifetime PTSD comorbidity: a latent class analysis
Depress. Anxiety
Dissociative symptoms as a consequence of traumatic experiences: the long-term effects of childhood sexual abuse
Isr. J. Psychiatry Relat. Sci.
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The authors declare that they have no competing interests.