Introduction
Traumatic eventa | No. of studies | Range of prevalence estimates | Comments |
---|---|---|---|
Rape [56,57] | >50 | 14%–80% | Completed rape is associated with the greatest risk of PTSD. |
Man-made disaster [58] | 106 | 25%–75% | Studies with highest prevalence estimates were conducted on subjects exposed to 'extreme' trauma shortly after the event. |
ICU | 16 | 5%–63% | Prevalence rates are extremely high relative to other medical populations. |
Natural disaster [58] | 86 | 5%–60% | Most studies report rates in the lower half of the 5%–60% range. |
Political refugee experience [59] | 22 | 4%–44% | Prevalence rates may be affected by the use of tools possibly insensitive to cultural expressions of PTSD. |
Cancer survivors [60] | >100 | 1.9%–39% | Prevalence rates are quite controversial due to debate over status of cancer as a traumatic stressor. |
MVA survivors [61] | >100 | 7.6%–34% | Many MVA survivors have histories of prior trauma, thus PTSD symptoms may be pre-existing. |
MI survivors [62] | 4 | 0%–16% | Prevalence studies are limited and have small sample sizes. |
Combat in Vietnam [63,64] | >100 | 1.8%–15% | Prevalence estimates of subpopulations of Vietnam veterans (such as those injured in combat) are higher than 15%. |
Definition of post-traumatic stress disordera |
A potentially debilitating psychiatric condition that develops as the result of being exposed to a traumatic occurrence 'in which a person experienced, witnessed, or was confronted with an event or events that involved actual or threatened death or serious injury, or a threat to the physical integrity of self or others' and which generates 'intense feelings of fear, helplessness, or horror' in those exposed to the trauma. This condition is characterized by a constellation of symptoms in three domains: |
A. Symptoms of re-experiencing (for example, intrusive thoughts and upsetting recollections of the trauma, recurrent dreams or nightmares, and flashbacks). |
B. Symptoms of avoidance and emotional numbing (for example, efforts to avoid conversations, places, and thoughts associated with the trauma; detachment from others; and a restricted range of affect). |
C. Symptoms of increase arousal (for example, sleep disruption, hypervigilance, and exaggerated startle response). |
These symptoms must meet two criteria to satisfy diagnostic criteria: |
1. Symptoms must cause significant impairment in social, occupational, or other important functional domains. |
2. Symptoms must be present for at least 1 month after exposure to the traumatic event or events. |
Materials and methods
Study identification and selection
Study inclusion criteria and evaluation
Data extraction and analysis
Results
Search for articles
Study | Population | Design | Quality ratinga | Number lost to follow-upb | Follow-up time point | Tool | Rate of PTSD or PTSS | Risk factors |
---|---|---|---|---|---|---|---|---|
Rattray et al., 2005 [16] | General medical ICU | Prospective cohort | 2b | 109 enrolled at discharge, 87 at 6 months, 80 at 12 months; 27% lost to follow-up | Hospital discharge, 6 months, and 12 months | IES | 20% with high avoidance scores and 18% with high intrusion scores | Avoidance and intrusive symptoms related to younger age, 'frightening' ICU experience, APACHE II scores, ICU/hospital lengths of stay, and recall of experiences |
Capuzzo et al., 2005 [9] | General medical ICU | Prospective cohort | 2b | 84 at 1 week, 63 at 3 months; 25% lost to follow-up | 1 week and 3 months | IES | 5% with PTSS | PTSD symptoms associated with fewer factual memories |
Cuthbertson et al., 2004 [10] | General medical ICU | Prospective cohort | 2b | 111 enrolled, 78 completed; 30% lost to follow-up | 3 months | DTS | 14% with PTSD | PTSD associated with younger age, length of mechanical ventilation, and previous psychiatric history |
Nickel et al., 2004 [11] | General medical ICU | Cross-sectional | 3b | 41; percentage lost to follow-up not recorded | Unknown | PTSS-10, SCID | 17% with PTSS; 9.76% with PTSD | PTSD associated with previous psychiatric history |
Jones et al., 2003 [12] | General medical ICU | Randomized controlled trial | 1b | 126 eligible patients, 114 at 8 weeks, 102 at 6 months; 20% lost to follow-up | 8 weeks and 6 months | IES | 51% with probable PTSD at 6-month follow-up | Presence of delusional memories increased risk of PTSD symptoms |
Kress et al., 2003 [13] | General medical ICU | Prospective cohort | 2b | 105 patients enrolled, 32 at follow-up; 70% lost to follow-up | ~1 year | IES-R, clinical interview | 18.5% with PTSD; 54% from control group; 0 from intervention group | Presence of delusional memories increased the risk of PTSD; sedative interruption decreased the risk of PTSD |
Schelling et al., 2001c [1] | General medical ICU | Retrospective cohort | 2b | 24 eligible, 20 completed testing; 16% lost to follow-up | 21 to 49 months | PTSS-10, SCID | 40% with PTSD (63% placebo group; 11% treatment group) | Administration of hydrocortisone related to a lower incidence of PTSD in ICU survivors |
Scragg et al., 2001 [14] | General medical ICU | Cross-sectional | 3b | 142 eligible, 80 usable surveys returned; 44% lost to follow-up | >5 years | IES, TSC-33, ETIC-7 | 30% with PTSS; 15% with PTSD | Female gender/younger age associated with increased PTSD risk |
Eddleston et al., 2000 [15] | General medical ICU | Prospective cohort | 2b | 227 available, 143 completed; 37% lost to follow-up | 3 months | Selected PTSD questions | 36% with 'distressing flashbacks' | Female gender related to increased risk of distressing flashbacks |
Deja et al., 2006 [23] | ARDS survivors | Retrospective cohort | 2b | 129 enrolled, 65 at follow-up; 50.4% lost to follow-up | 57 ± 32 months | PTSS-10 | 29% with 'high risk' of PTSD | PTSD associated with anxiety in the ICU; perceived social support related to decreased risk of PTSD |
Kapfhammer et al., 2004 [17] | ARDS survivors | Retrospective cohort | 3b | 80 in the original study, 46 at follow-up; 42% lost to follow up | Median of 8 years | PTSS-10, SCID | 43% with PTSD at discharge; 23.9% with PTSD at follow-up | PTSD was associated with greater ICU length of stay |
Shaw et al., 2001 [20] | ARDS survivors | Cross-sectional | 3b | 20; N/A | Unknown | IES | 35% with PTSS | Unknown |
Stoll et al., 1999d [18] | ARDS survivors | Retrospective cohort | 3b | 52; 35% lost to follow-up | Two time points at least 2 years apart (1 to 13 years after discharge) | PTSS-10, clinical interview | 25% with PTSD | Greater number of traumatic memories associated with increased frequency and intensity of PTSD |
Schelling et al., 1998d [19] | ARDS survivors | Retrospective cohort | 2b | 80; 22% lost to follow-up | 6 to 10 years, median 4 years | PTSS-10 | 27.5% with PTSD | Number of adverse experiences associated with higher PTSS-10 scores |
Schelling et al., 1999c [22] | Septic shock survivors | Retrospective cohort | 2b | 54; percentage lost to follow-up not recorded | 2 to 9 years | PTSS-10, clinical interview | 38% with PTSD (18.5% with PTSD in treatment group; 59% in control group) | PTSD associated with longer ICU treatment and increased number of traumatic experiences |
Nelson et al., 2000 [21] | Acute lung injury survivors | Cross-sectional | 3b | 34 eligible, 24 completed; 29% lost to follow-up | 6 to 41 months, mean 19 months | Seven items pertaining to PTSD | 39% with 'bad memories or dreams' | Deeper levels of sedation and neuromuscular blockade exposure associated with increased risk of PTSD |
Methods of reviewed articles
Subject characteristics
Study design
Exclusion criteria/identification of pre-existing psychiatric illness
Methods of assessing PTSD
Primary findings
How prevalent is ICU-related PTSD?
Risk factors for PTSD
Known risk factors for PTSD or PTSD symptoms in the ICU |
ICU length of stay (longer duration) |
Hospital stay (longer duration) |
Length of mechanical ventilation |
Greater levels of sedation |
Female gendera |
Younger agea |
Pre-existing psychiatric historya |
Greater number of traumatic memories/frightening recollectionsa |
Presence of delusional memoriesa |
Discussion
Challenges to studying PTSD
Limitations of existing studies
Critical illness as a traumatic stressor
Conclusion
Key messages
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PTSD or PTSD symptoms are reported to occur in between 5% and 63% of ICU survivors, and key risk factors include duration of hospital and ICU stays, duration of ventilation, pre-existing psychiatric history, and the presence of delusional memories.
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Reported rates of PTSD prevalence following the ICU tend to be extremely high relative to other trauma populations, including medical and surgical patients, and are likely to be overestimates.
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Studies of PTSD following critical illness are characterized by significant methodological shortcomings, which raise key questions about the actual prevalence rates of PTSD and the generalizability of study findings.
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Future studies on PTSD should be more methodically rigorous and should use larger and more homogeneous samples while also employing comprehensive diagnostic, as opposed to screening, instruments.