This study investigates lifetime prevalence rates, demographic characteristics, childhood conduct disorder and adult antisocial features, suicide attempts, and cognitive impairment in individuals with obsessive-compulsive disorder (OCD) uncomplicated by or comorbid with any other psychiatric disorder. The data are from the NIMH Epidemiological Catchment Area (ECA) study, and the current analyses compared subjects with uncomplicated OCD (no history of any other lifetime psychiatric disorder) comorbid OCD (with any other lifetime disorder), other lifetime psychiatric disorders, and no lifetime psychiatric disorders across these variables. OCD in its uncomplicated and comorbid form had significantly higher rates of childhood conduct symptoms, adult antisocial personality disorder problems, and of suicide attempts than did no or other disorders. Comorbid OCD subjects had higher rates of mild cognitive impairment on the Mini-Mental Status Exam than did subjects with other disorders. These findings suggest that a subgroup of OCD patients may have impulsive features, including childhood conduct disorder symptoms and an increased rate of suicide attempts; wider clinical attention to these outcomes is needed.

Posttraumatic stress disorder (PTSD) was associated in the past mainly with combatrelated events. This was reflected in the names given to the disorder, ie, “shell shock,” “soldier's heart,” “combat neurosis,” and “operational fatigue.” Only following the realization that PTSD can be related to all types of traumatic events, including noncombat associated events, were the terms “traumatic neurosis” and, later, “PTSD” coined. These new terms reflect the understanding that the condition need not necessarily be associated with war, but may also be related to events such as a severe automobile accident, violent personal assault (eg, rape, physical attack, robbery, or mugging), terrorist attack, natural or human-made disaster (such as a fire), witnessing serious injury or death due to any of the above, as well as to other situations, such as being kidnapped or being held hostage.

The tendency to interpret the symptoms of what we would consider now as PTSD, as a “normal response” to traumatic events was another factor that held up progress in the field. It is important to note that PTSD is a pathological response: The vast majority of individuals who are exposed to a traumatic event will later adapt and continue on with their lives. Only a small percent, which partially depends on the type of trauma and is partially associated with several risk factors, will develop a pathological fixation on the traumatic event, namely, PTSD.

It has been estimated that approximately one-third of the population will be exposed to a severe trauma (according to the definition of PTSD) during their lifetime.

This article reviews a series of studies conducted on Israeli war veterans that assessed the interrelationship of posttraumatic stress disorder (PTSD) and comorbid disorder, focusing on five issues in particular: (1) the frequency of comorbidity among veterans diagnosed with PTSD; (2) how this comorbidity can be accounted for; (3) whether PTSDs with and without comorbidity are different; (4) the validity of PTSD as a distinct diagnosis; and (5) the clinical implications of comorbidity of PTSD.