Delayed onset of PTSD

How common is delayed posttraumatic stress disorder?
Burstein, Allan
The American Journal of Psychiatry, Vol 142(7), Jul, 1985. pp. 887.
Abstract:
Presents data from a review of the case records of 120 patients who met the DSM-III criteria for posttraumatic stress disorder (PTSD), in order to determine whether the onset of symptoms in PTSD are really delayed, rather than gradual, in onset. Data suggest that delayed PTSD is a relatively rare phenomenon. Two cases of delayed PTSD, which occurred 4 and 12 mo after motor vehicle accidents, are described.

Capgras-like symptoms in a delayed posttraumatic stress disorder: A clinical riddle.
Mester, Roberto and Braun, Peter
Israel Journal of Psychiatry and Related Sciences, Vol 23(1), 1986. pp. 77-81.
Abstract:
Reports the presence of Capgras-like symptoms in a 43-yr-old male suffering from a delayed posttraumatic stress disorder (PTSD). The S’s symptoms disappeared during psychotherapy, which involved elaboration of mourning for a friend’s death; S was still symptom-free at 6-mo follow-up. The psychodynamic meanings of the Capgras-like manifestations in the context of PTSD, as revealed by psychotherapy, are discussed.

Differences between posttraumatic stress disorder patients with delayed and undelayed onsets.
Watson, Charles G., et al.
Journal of Nervous and Mental Disease, Vol 176(9), Sep, 1988. pp. 568-572.
Abstract:
31 Vietnam veteran inpatients with delayed posttraumatic stress disorder (PTSD) and 32 Ss with un-delayed PTSD onset completed PTSD symptom self-ratings, the Minnesota Multiphasic Personality Inventory (MMPI), stress histories, and repression scales. Findings show that the delayed and non-delayed stress disorders did not significantly differ in either the pattern of symptoms they presented or in the severity of these symptoms. Data indicate that the disorders should not be identified as separate illnesses

Distinguishing features of delayed-onset posttraumatic stress disorder.
Ramchandani, Dilip
Bulletin of the Menninger Clinic, Vol 54(2), Spr 1990. pp. 247-254.
Abstract:
Summarizes literature on patients with delayed posttraumatic stress disorder (PTSD) and describes the cases of 3 veterans (aged 40, 64, and 75 yrs) who became symptomatic after a delay of several years. Common features in these patients and those reported in the literature include long periods of good postwar adjustment, no significant concern about personal safety during combat, preoccupation with guilt feelings about relatively circumscribed acts of omission or commission during combat, and histories of sustained depression. These patients may respond to individual psychoanalytic psychotherapy that focuses on the circumscribed, depressive guilt (H. J. Schwartz, 1984) and on the mourning, rather than on the vengeance-seeking aspects of aggression.

Delayed onset PTSD among Israeli veterans of the 1982 Lebanon War.
Solomon, Zahava, et al.
Sihot/Dialogue: Israel Journal of Psychotherapy, Vol 5(1), Nov, 1990. pp. 32-37.
Abstract:
Describes an exploratory study that investigated the nature, process, and incidence of posttraumatic stress disorder (PTSD) among Israeli soldiers who fought in the 1982 Lebanon War. 150 medical files of soldiers, who sought mental health assistance in the period between 6 mo and 5 yrs following the war, were examined. Results show that only 10% of the investigated cases were actually of a PTSD nature. In most cases there was no delay in the onset of the disorder, but only in seeking professional help.

Delayed and immediate onset posttraumatic stress disorder: II. The role of battle experiences and personal resources.
Solomon, Zahava, et al.
Social Psychiatry and Psychiatric Epidemiology, Vol 26(1), Jan, 1991. pp. 8-13.
Abstract:
Continues the discussion (see record 1991-21559-001) of the role battle experiences and personal resources play in the development of combat-related posttraumatic stress disorder (PTSD). For this purpose, battle experiences (battle stress, military unit environment) and personal resources (coping styles, causal attribution) were assessed 2 yrs after the 1982 Lebanon War in 3 groups of male Israeli frontline soldiers (N = 217). Both immediate and delayed PTSD casualties reported similar and higher levels of battle stress than control Ss. Delayed PTSD casualties evinced less personal resources than control Ss, and immediate PTSD casualties evinced still less personal resources than delayed PTSD casualties.

Delayed and immediate onset posttraumatic stress disorder: I. Differential clinical characteristics.
Solomon, Zahava, et al.
Social Psychiatry and Psychiatric Epidemiology, Vol 26(1), Jan, 1991. pp. 1-7.
Abstract:
Compared the clinical picture of 3 groups of veterans: posttraumatic stress disorder (PTSD) casualties (71 Ss) who sought help at least 6 mo after their exposure to combat; PTSD casualties (73 Ss) who sought help during the 1982 Lebanon War; and 73 soldiers who emerged from the 1982 war without any diagnosable psychiatric disorder (controls). Significant differences were found in the clinical picture of the study groups. Both treated groups, the delayed and the immediate onset PTSD casualties, showed significantly more trauma-related intrusion and avoidance responses, more severe psychiatric symptomatology, more problems in social functioning, and lower perceived self efficacy in combat than non-PTSD controls.

Delayed and immediate onset posttraumatic stress disorder: The role of life events and social resources.
Solomon, Zahava, et al.
Journal of Community Psychology, Vol 19(3), Jul, 1991. pp. 231-236.
Abstract:
Examined the role of life events and social resources in the development of combat-related posttraumatic stress disorder (PTSD) after homecoming. Life events after homecoming and social resources (social integration, loneliness, satisfaction with social networks, family environment) were assessed 2 yrs after the 1982 Lebanon War in 217 male Israeli frontline soldiers who participated in the war. Delayed PTSD, immediate PTSD, and control groups were matched for military and sociodemographic background. Findings indicate that both control and delayed PTSD casualties reported similar and fewer life events at homecoming than did immediate PTSD casualities. However, delayed PTSD casualties reported less social resources than did controls.

Delayed onset of PTSD: Delayed recognition or latent disorder?
Pomerantz, Andrew S.
The American Journal of Psychiatry, Vol 148(11), Nov, 1991. pp. 1609.
Abstract:
Presents the case history of a 63-yr-old male war veteran referred for psychiatric evaluation. The patient appeared to be free from psychiatric symptoms for nearly 40 yrs because he had worked at an active, physically demanding job. Classic symptoms of posttraumatic stress disorder (PTSD) followed his inability to maintain these activities. The delayed onset of the disorder suggests latent rather than unrecognized PTSD.

Delayed onset post-traumatic stress disorder in World War II veterans.
Herrmann, N. and Eryavec, G.
The Canadian Journal of Psychiatry / La Revue canadienne de psychiatrie, Vol 39(7), Sep, 1994.
Abstract:
Reports 2 cases of posttraumatic stress disorder (PTSD) in World War II veterans (aged 68 and 72 yrs) whose individual onset was delayed for over 30 yrs after their wartime experiences. The onset of PTSD symptoms seemed to be associated with the stresses of late life, including bereavement, social isolation, and chronic medical illness. Theories regarding the etiology of PTSD are reviewed, and a hypothesis suggesting a heterogeneous condition is proposed.

Clinical characteristics of delayed and immediate-onset combat-induced post traumatic stress disorder.
Solomon, Zahava and Blumenfeld, Amir
Military Medicine, Vol 160(9), Sep, 1995. pp. 425-430.
Abstract:
Examined clinical characteristics of war-related disturbances among veterans with delayed and immediate-onset posttraumatic stress disorder (PTSD). 125 veterans who sought help for war-related disturbances, 8 yrs after the 1982 Lebanon War, filled out the PTSD Inventory, Impact of Event Scale, and SCL-90. Scores were compared with those of 370 treated combat stress reaction casualties who filled out questionnaires 1 yr after the same war. Findings indicate that Ss from the delayed-help seeking group (8 yrs post war) suffer from a higher rate and a greater intensity of PTSD, more intrusive tendencies, and more severe general psychiatric symptomatology than those of the immediate-help seeking group (1 yr post war). Findings indicate that a fair number of combatants still seek help for war-related disturbances almost a decade after the war. The complex relationship between delayed-help seeking and delayed-onset PTSD is discussed.

A prospective examination of delayed onset PTSD secondary to motor vehicle accidents.
Buckley, Todd C., et al.
Journal of Abnormal Psychology, Vol 105(4), Nov, 1996. pp. 617-625.
Abstract:
Seven participants who did not meet the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) criteria for posttraumatic stress disorder (PTSD) 1-4 months post-motor vehicle accident (MVA) and developed delayed onset PTSD during a 1-year follow-up interval were compared with 38 MVA controls who did not develop PTSD, as well as to 62 MVA participants who met criteria for acute onset PTSD on variables related to demographics, pre-MVA functioning, post-MVA functioning, and follow-up. The delayed onset participants were more symptomatic at the time of the initial interview than the controls. The delayed onset participants had poorer social support than the controls prior to and after the MVA. For the month prior to the MVA, the delayed onset participants had lower Global Assessment of Functioning scores than the controls.

Combat trauma: Trauma with highest risk of delayed onset and unresolved posttraumatic stress disorder symptoms, unemployment, and abuse among men.
Prigerson, Holly G., et al.
Journal of Nervous and Mental Disease, Vol 189(2), Feb, 2001. pp. 99-108.
Abstract:
Little is known about the risk and course of posttraumatic stress disorder (PTSD), and other forms of dysfunction, associated with combat trauma relative to other traumas. Modified versions of the Diagnostic and Statistical Manual of Mental Disorders-III-Revised (DSM-III-R) PTSD module from the Diagnostic Interview Schedule and Composite International Diagnostic Interview were administered to a representative national sample of 5,877 Ss (15–54 yrs old) in the part 2 subsample of the National Comorbidity Survey. Of the weighted subsample, 1,703 men reported a traumatic event. The risk of PTSD and other forms of dysfunction were compared for men who nominated combat as their worst trauma vs men nominating other traumas as worst, controlling for confounding influences. Men reporting combat as their worst trauma were more likely to have lifetime PTSD, delayed PTSD symptom onset, and unresolved PTSD symptoms, and to be unemployed, fired, divorced, and physically abusive to their spouses than men reporting other traumas as their worst experience.

Delayed posttraumatic stress disorder (PTSD) and predictors of first onset of PTSD in patients with anxiety disorders.
Zlotnick, Caron, et al.
Journal of Nervous and Mental Disease, Vol 189(6), Jun, 2001. pp. 404-406.
Abstract:
Using a prospective and longitudinal design with a clinical sample of patients with anxiety disorders, this study explored the following questions: (1) what is the likelihood of a 1st onset of posttraumatic stress disorder (PTSD) many years after trauma exposure? (2) are patients who have a delayed onset of PTSD different from those with longstanding PTSD? and (3) among those at risk for PTSD (i.e., have trauma histories) are there features that increase the risk of onset of PTSD? Of the 655 patients with anxiety disorders and no PTSD at intake, 1st onset of delayed PTSD occurred in 9% of Ss with histories of trauma within a 7-yr follow-up interval. The only significant difference between chronic PTSD and 1st cases of delayed PTSD was that 1st cases had a greater likelihood of childhood trauma than chronic cases. Among Ss with histories of trauma at intake, patients with a 1st onset of delayed PTSD were more likely than those with no PTSD to have a greater number of comorbid axis I and axis II disorders, more suicidal attempts and gestures, and more traumatic experiences, especially childhood trauma. Among patients at risk for delayed PTSD, those who go on to develop PTSD are more similar, premorbidly, to patients who already have PTSD than to those who have trauma histories only.

Delayed-onset posttraumatic stress disorder: A prospective evaluation.
Bryant, Richard A., Harvey, Allison G.
Australian and New Zealand Journal of Psychiatry, Vol 36(2), Apr, 2002. pp. 205-209.
Abstract:
Delayed onset posttraumatic stress disorder (PTSD) refers to PTSD that develops at least 6 mo after the traumatic event. This study aimed to index the features of patients who develop delayed-onset PTSD. The authors investigated delayed onset PTSD by prospectively assessing 103 motor vehicle accident survivors (aged 17-63 yrs) within 1 mo of the motor vehicle accident for acute stress disorder, and subsequently assessing them for PTSD 6 mo post-accident, and 2 yrs post-accident. Patients were initially assessed for symptoms of traumatic stress, anxiety, depression, and resting heart rate. Five patients displayed PTSD 2 yrs post-trauma without meeting PTSD criteria 6 mo post-trauma. Delayed onset cases were characterized by elevated psychopathology scores and resting heart rate levels within the initial month and elevated psychopathology 6 mo post-trauma. These findings suggest that cases of delayed onset PTSD suffer subsyndromal levels of posttraumatic stress prior to the diagnosis of PTSD. These findings challenge the notion of PTSD developing after a period without symptoms.

Delayed Onset of Posttraumatic Stress Disorder Among Male Combat Veterans: A Case Series.
Ruzich, Michelle J., et al.
The American Journal of Geriatric Psychiatry, Vol 13(5), May, 2005. pp. 424-427.
Abstract:
Objective: Authors investigated the nature of delayed-onset posttraumatic stress disorder (PTSD) among combat veterans. Methods: PTSD, along with cognitive and emotional functioning, was assessed in a case series of elderly Australian war veterans. Results: Fifteen elderly male subjects consecutively referred to an outpatient psychiatric clinic were identified as having PTSD with significantly delayed onset. In most cases, the onset of PTSD symptoms was associated with unrelated medical complaints, psychosocial stress, and/or mild cognitive impairment. Conclusion: Environmental stressors, coupled with age-related neurodegeneration, may potentially contribute to the late-life recrudescence or emergence of PTSD symptoms in veterans exposed to combat-related trauma.

Delayed-onset PTSD: A prospective study of injury survivors.
Carty, Jessica, et al.
Journal of Affective Disorders, Vol 90(2-3), Feb, 2006. pp. 257-261.
Abstract:
Background: Recent studies have indicated that delayed-onset posttraumatic stress disorder (PTSD) (i.e., the development of PTSD more than 6 months post-trauma) is generally characterized by subsyndromal diagnoses within the first 6 months. This study sought to examine the relationship between sub-clinical levels of PTSD symptoms at 3 months post-trauma and delayed onset PTSD at 12 months in a large sample of traumatic injury survivors. Methods: Three hundred and one consecutively admitted injury survivors were assessed at 3 and 12 months post-trauma. PTSD was diagnosed according to DSM-IV criteria, while partial and subsyndromal diagnoses were based on recent definitions developed by Mylle and Maes [Mylle, J., Maes, M., 2004. Partial posttraumatic stress disorder revisited. J. Affect. Disord. 78, 37-48]. Results: Eight percent of participants was diagnosed with 3-month PTSD while 10% was diagnosed with 12-month PTSD. Nearly half (47%) of 12-month PTSD cases were of delayed onset. The majority of those with delayed-onset were diagnosed with partial or subsyndromal PTSD at 3 months. Ten percent of delayed onset cases did not meet partial or subsyndromal criteria. Limitations: As symptoms were not assessed at 6 months (the DSM cut-off for delayed PTSD), it could not be conclusively determined that delayed-onset cases had not developed PTSD between 3 and 6 months post-trauma. Conclusion: A considerable proportion of 12-month PTSD diagnoses was delayed in onset. While most demonstrated 3-month morbidity in the form of partial and subsyndromal diagnoses, a minority did not. Thus, clinicians should consider subthreshold diagnoses as potential risk factors for delayed-onset PTSD. Future research is required to identify factors that may predict delayed-onset PTSD in trauma survivors without evidence of prior PTSD pathology.

Predictors of PTSD and Delayed PTSD After Disaster: The Impact of Exposure and Psychosocial Resources.
Adams, Richard E., Boscarino, Joseph A.
Journal of Nervous and Mental Disease, Vol 194(7), Jul, 2006. pp. 485-493.
Abstract:
In the present study we sought to identify factors associated with posttraumatic stress disorder (PTSD) following the World Trade Center Disaster (WTCD) and examine changes in PTSD status over time. Our data come from a two-wave, prospective cohort study of New York City adults who were living in the city on September 11, 2001. We conducted a baseline survey 1 year after the attacks (year 1), followed by a survey 1 year later (year 2). Overall, 2,368 individuals completed the year 1 survey, and 1,681 were interviewed at year 2. Analyses for year 1 indicated that being younger, being female, experiencing more WTCD events, reporting more traumatic events other than the WTCD, experiencing more negative life events, having low social support, and having low self-esteem increased the likelihood of PTSD. For year 2, being middle-aged, being Latino, experiencing more negative life events and traumas since the WTCD, and having low self-esteem increased the likelihood of PTSD. Exposure to WTCD events was not related to year 2 PTSD once other factors were controlled. Following previous research, we divided study respondents into four categories: resilient cases (no PTSD years 1 or 2), remitted cases (PTSD year 1 but not year 2), delayed cases (no PTSD year 1 but PTSD year 2), and acute cases (PTSD both years 1 and 2). Factors predicting changes in PTSD between year 1 and year 2 suggested that delayed PTSD cases were more likely to have been Latino, to have experienced more negative life events, and to have had a decline in self-esteem. In contrast, remitted cases experienced fewer negative life events and had an increase in self-esteem. We discuss these findings in light of the psychosocial context associated with community disasters and traumatic stress exposures.

Delayed-onset posttraumatic stress disorder: A systematic review of the evidence.
Andrews, Bernice, et.al.
The American Journal of Psychiatry, Vol 164(9), Sep, 2007. pp. 1319-1326.
Abstract:
Objective: Since the diagnosis of delayed-onset posttraumatic stress disorder (PTSD) was introduced in DSM-III, there has been controversy over its prevalence and even its existence. The authors sought to resolve discrepant findings concerning the prevalence of delayed-onset PTSD by conducting a systematic review of the evidence. Method: A literature search was conducted for case reports and group studies with adequate measurement of delayed-onset PTSD according to DSM criteria. Studies that met inclusion criteria were examined for the defined length of delay for delayed-onset PTSD, presence of symptoms before full diagnostic criteria were met, length of follow-up, prevalence estimates, and other variables. Studies were also examined for differences between immediate-onset PTSD, delayed-onset PTSD, and no-PTSD cases. Results: Ten case studies and 19 group studies met criteria for inclusion in the review. Studies consistently showed that delayed-onset PTSD in the absence of any prior symptoms was rare, whereas delayed onsets that represented exacerbations or reactivations of prior symptoms accounted on average for 38.2% and 15.3%, respectively, of military and civilian cases of PTSD. Conclusions: The discrepant findings in the literature concerning prevalence can be largely, but not completely, explained as being due to definitional issues. Little is known about what distinguishes the delayed- onset and immediate-onset forms of the disorder. Continuing scientific study of delayed-onset PTSD would benefit if future editions of DSM were to adopt a definition that explicitly accepts the likelihood of at least some prior symptoms.

Delayed posttraumatic stress disorder: Systematic review, meta-analysis, and meta-regression analysis of prospective studies.
Smid, Geert E, et.al.
The Journal of Clinical Psychiatry, Vol 70(11), Nov, 2009. pp. 1572-1582.
Abstract:
Objective: Prevalence estimates of delayed posttraumatic stress disorder (PTSD) have varied widely in the literature. This study is the first to establish the prevalence of delayed PTSD in prospective studies and to evaluate associated factors through meta-analytic techniques. Data sources: Studies were located by an electronic search using the databases EMBASE, MEDLINE, and PsycINFO. Search terms were posttraumatic stress disorder[include all subheadings] AND (delayed OR prospective OR longitudinal OR follow-up). Results were limited to journal articles published between 1980 and April 4, 2008. Study selection: We included longitudinal, prospective studies of humans exposed to a potentially traumatic event that assessed participants at 1 to 6 months after the event, that included a follow-up of at least 12 months after the event, and that specified rates of new onset and remission between assessments in study completers. Data extraction: Data were extracted concerning the study design, demographic features, and event-related characteristics and the number of PTSD cases at first assessment, the number of PTSD cases among study dropouts, and the number of new event-related PTSD cases at each subsequent assessment among study completers. Data from 24 studies were included. Four of these provided additional data on initial subthreshold PTSD and subsequent risk of delayed PTSD. Data synthesis: The proportion of PTSD cases with delayed PTSD was 24.8% (95% CI = 22.6% to 27.2%) after adjusting for differences in study methodology, demographic features, and event-related characteristics. Military combat exposure, Western cultural background, and lower cumulative PTSD incidence were associated with delayed PTSD. Participants with initial subthreshold PTSD were at increased risk of developing delayed PTSD. Conclusions: Delayed PTSD was found among about a quarter of PTSD cases and represents exacerbations of prior symptoms.

Comparison of immediate-onset and delayed-onset posttraumatic stress disorder in military veterans.
Andrews, Bernice, et.al.
Journal of Abnormal Psychology, Vol 118(4), Nov, 2009. pp. 767-777.
Abstract:
Differences in symptoms, trauma exposure, dissociative and emotional reactions to trauma, and subsequent life stress in war veterans reporting immediate-onset or delayed-onset posttraumatic stress disorder (PTSD) or no PTSD were investigated. The role of life stress in delayed-onset PTSD was also studied. Retrospective interviews were conducted with 142 United Kingdom veterans receiving a war pension for PTSD or physical disability. Immediate-onset and delayed-onset PTSD were similar in the number and type of symptoms reported at onset, but the delayed-onset group differed in showing a gradual accumulation of symptoms that began earlier and continued throughout their military career. They were more likely to report major depressive disorder and alcohol abuse prior to PTSD onset. Both groups described similar amounts of trauma exposure, but those in the delayed-onset group reported significantly less peritraumatic dissociation, anger, and shame. Veterans with delayed onsets were more likely than veterans with no PTSD to report the presence of a severe life stressor in the year before onset. In conclusion, the results suggest that delayed onsets involve a more general stress sensitivity and a progressive failure to adapt to continued stress exposure.

Delayed-onset PTSD among war veterans: The role of life events throughout the life cycle.
Horesh, Danny, et.al.
Social Psychiatry and Psychiatric Epidemiology, Vol 46(9), Sep, 2011. pp. 863-870.
Abstract:
Background: The underlying mechanisms of delayed-onset PTSD are yet to be understood. This study examines the role of stressful life events throughout the life cycle in delayed-onset PTSD following combat. Methods: 675 Israeli veterans from the 1982 Lebanon War, 369 with antecedent combat stress reaction (CSR) and 306 without CSR were assessed prospectively, 1, 2 and 20 years after the war. Veterans were divided into four groups, according to the time of first PTSD onset (first onset at 1983, 1984, and 2002 and no PTSD onset). They were assessed for post-, peri- and pre-traumatic life events, as well as military and socio-demographic characteristics. Results: Our findings indicate that shorter delays in PTSD onset were associated with a higher risk for CSR, a higher number of pre- and post-war life events, more severe subjective battle exposure, greater perceived danger during combat and a more stressful military position. CSR was found to be the most powerful predictor of PTSD onset. A recency effect was also found, with more recent life events proving to be stronger predictors of PTSD onset. Conclusions: First, our findings validate the existence of delayed-onset PTSD, as it was found among a substantial number of participants (16.5%). Second, post-, peri- and pre-traumatic life events are associated with the time of PTSD onset. Thus, practitioners and researchers are encouraged to examine not only the original trauma, but also the stressful experiences throughout the survivors’ life cycle. In particular, identification of antecedent CSR may help mental help professionals in targeting high-risk populations.

Prevalence of delayed-onset posttraumatic stress disorder in military personnel: Is there evidence for this disorder? Results of a prospective UK cohort study.
Goodwin, Laura, et.al.
Journal of Nervous and Mental Disease, Vol 200(5), May, 2012. pp. 429-437.
Abstract:
Delayed-onset posttraumatic stress disorder (PTSD) is defined as onset at least 6 months after a traumatic event. This study investigates the prevalence of delayed-onset PTSD in 1397 participants from a two-phase prospective cohort study of UK military personnel. Delayed-onset PTSD was categorized as participants who did not meet the criteria for probable PTSD (assessed using the PTSD Checklist Civilian version) at phase 1 but met the criteria by phase 2. Of the participants, 3.5% met the criteria for delayed-onset PTSD. Subthreshold PTSD, common mental disorder (CMD), poor/fair self-reported health, and multiple physical symptoms at phase 1 and the onset of alcohol misuse or CMD between phases 1 and 2 were associated with delayed-onset PTSD. Delayed-onset PTSDexists in this UK military sample. Military personnel who developed delayed-onset PTSD were more likely to have psychological ill-health at an earlier assessment, and clinicians should be aware of the potential comorbidity in these individuals, including alcohol misuse. Leaving the military or experiencing relationship breakdown was not associated.

Prevalence, correlates, and clinical features of delayed-onset posttraumatic stress disorder in a nationally representative military sample.
Fikretoglu, Deniz, et.al.
Social Psychiatry and Psychiatric Epidemiology, Vol 47(8), Aug, 2012. pp. 1359-1366.
Abstract:
Purpose: Since its inclusion in the Diagnostic and Statistical Manual of Mental Disorders, there has been skepticism over the validity of delayed-onset posttraumatic stress disorder (PTSD). Paucity of research on the correlates and the clinical consequences of delayed-onset PTSD have historically added to this skepticism. The objective of this study was to address an important gap in the literature by examining the prevalence, the correlates, and the clinical consequences of delayed-onset PTSD using data from a large epidemiological survey. Methods: Data were drawn from the Canadian Community Health Survey-Canadian Forces Supplement (N = 8,441), a cross-sectional epidemiological survey of mental health in the Canadian Forces. Logistic regressions were used to identify correlates of delayed onset. Cox regressions were used to examine the impact of delayedonset on symptom duration. Results: The prevalence of delayed-onset PTSD in this Canadian population was less than 1%. Delayed-onset cases accounted for 8.5% of all PTSD cases. Experiencing trauma in early childhood, experiencing a repeated trauma, and serving in the land troops were all associated with greater likelihood of developing delayed-onset PTSD. Delayed onset, after controlling for important sociodemographic, military, and clinical variables, was associated with greater symptom duration. Conclusions: The phenomenon of delayed-onset PTSD, albeit uncommon, does exist. Certain trauma characteristics may increase the risk for developing delayed-onset PTSD. Delayed onset may be associated with more chronic forms of this disorder.

Exploration of delayed-onset posttraumatic stress disorder after severe injury.
O’Donnell, Meaghan L., et.al.
Psychosomatic Medicine, Vol 75(1), Jan, 2013. pp. 68-75.
Abstract:
Objective: The first aim of this work was to conduct a rigorous longitudinal study to identify rates of delayed-onset posttraumatic stress disorder (PTSD) in a sample of patients with severe injury. The second aim was to determine what variables differentiated delayed-onset PTSD from chronic PTSD. Methods: Randomly selected patients with injury who were admitted to four hospitals around Australia were recruited to the study (N = 834) and assessed in the acute care hospital, at 3 months, and at 12 months. A structured clinical interview was used to assess PTSD at each time point. Results: Seventy-three patients (9%; n = 73) had PTSD at 12 months. Of these, 39 (53%) were classified as having delayed-onset PTSD. Furthermore, 22 (56%) patients with delayed-onset PTSDhad minimal PTSD symptoms at 3 months (i.e., they did not have partial/subsyndromal PTSD at 3 months). The variables that differentiated delayed-onset PTSD from chronic PTSD were greater injury severity (odds ratio [OR] = 1.13; 95% confidence interval [CI] = 1.02-1.26), lower anxiety severity at 3 months (OR = 0.73; 95% CI = 0.61-0.87), and greater pain severity at 3 months (OR = 1.39; 95% CI = 1.06-1.84). Conclusions: Delayed-onset PTSDoccurred frequently in this sample. Approximately half of the patients with delayed-onset PTSD had minimal PTSD symptoms at 3 months; therefore, their delayed-onset PTSD could not be accounted for by a small number of fluctuating symptoms. As we move toward DSM-V, it is important that research continues to explore the factors that underpin the development of delayed-onset PTSD.

Delayed‐onset PTSD after combat: The role of social resources.
Horesh, Danny, et.al.
Journal of Community Psychology, Vol 41(5), Jul, 2013. pp. 532-548.
Abstract:
Delayed-onset posttraumatic stress disorder (DPTSD) has been under medico-legal debate for years. Previous studies examining the prevalence and underlying mechanisms of DPTSD have yielded inconclusive findings. This study examined the role of social resources and warzone exposure in DPTSD. Six hundred and seventy-five Israeli veterans from the 1982 Lebanon War, 369 with antecedent combat stress reaction (CSR) and 306 without CSR, were assessed prospectively, 1, 2, and 20 years after the war. Veterans were divided into 4 groups, according to the time of first PTSD onset (first onset at 1983, 1984, and 2002 and no-PTSD onset). Participants completed self-report questionnaires tapping various social resources (social network support, family environment, military company environment, homecoming reception), as well as subjective and objective warzone exposure. Our results show that a significant portion (16.5%) of the veterans reported DPTSD. As hypothesized, social resources were found to be implicated in DPTSD. Interestingly, however, social resources accounted for long—not short—delays in PTSD onset. In addition, higher levels of both objective and subjective battle exposure were associated with a more immediate PTSD onset. Finally, CSR was found to be the most powerful predictor of DPTSD. Theoretical and clinical implications of these findings are discussed.

Occurrence of delayed-onset post-traumatic stress disorder: A systematic review and meta-analysis of prospective studies.
Utzon-Frank, Nicolai., et.al.
Scandinavian Journal of Work, Environment & Health, Vol 40(3), May, 2014. pp. 215-229.
Abstract:
Objective: Post-traumatic stress disorder (PTSD) develops according to consensus criteria within the first 1–6 months after a horrifying traumatic event, but it is alleged that PTSD may develop later. The objective was to review the evidence addressing occurrence of PTSD with onset >6 months after a traumatic event (delayed-onset PTSD). Methods: Through a systematic search in PubMed, EMBASE, and PsycINFO, we identified 39 studies with prospective ascertainment of PTSD. A meta-analysis was performed in order to obtain a weighted estimate of the average proportion of delayed-onset PTSD cases, and meta-regression was used to examine effects of several characteristics. Results: Delayed-onset PTSD was reported in all studies except one, and the average prevalence across all follow-up time was 5.6% [95% confidence interval (95% CI) 4.3–7.3%]. The proportion with delayed-onset PTSD relative to all cases of PTSD was on average 24.5% (95% CI 19.5–30.3%) with large variation across studies. In six studies with sub-threshold symptom data, delayed-onset PTSD seemed most likely an aggravation of early symptoms. The proportion with delayed-onset PTSD was almost twice as high among veterans and other professional groups compared to non-professional victims. Conclusion: Descriptive follow-up data suggest that PTSD may manifest itself >6 months after a traumatic event, delayed-onset PTSD most often, if not always, is preceded by sub-threshold PTSD symptoms, and a higher proportion of PTSD cases are delayed among professional groups. Contextual factors and biased recall may inflate reporting of PTSD and a cautious interpretation of prevalence rates seems prudent.

Vietnam Veteran perceptions of delayed onset and awareness of posttraumatic stress disorder.
Hermes, Eric. et.al.
Psychiatric Quarterly, Vol 86(2), Jun, 2015. pp. 169-179.
Abstract:
Although 40 years have passed since the Vietnam War, demand for treatment of posttraumatic stress disorder (PTSD) among veterans from this conflict has increased steadily. This study investigates the extent to which two factors, delayed onset or awareness of PTSD symptoms, may influence this demand. Using data from two studies of Vietnam Veterans in outpatient (n = 353) and inpatient (n = 721) PTSD treatment, this analysis examines retrospective perceptions of the time of symptom onset and awareness of the connection between symptoms and war-zone stress. The association of these two constructs with pre-war, wartime, and post-war clinical variables are analyzed. Delay in onset of symptoms was reported by 50% of outpatients and 35% of inpatients. Delay in awareness was reported by 60% of outpatients and 65% of inpatients. Onset of symptoms occurred within six years and onset of awareness within 20 years in 90% of individuals. Reported delays in onset and awareness were associated with more numerous negative life events after military service and before the onset of symptoms. Findings suggest that providers, administrators, and policy makers should be aware of the potential for protracted treatment demand among veterans from current conflicts, due in part by delay in onset and awareness of symptoms.