Understanding posttraumatic stress disorder-related symptoms after critical care: the early illness amnesia...

To assess the factual and delusional memories reported by intensive care unit survivors and its relationship with the development of Posttraumatic Stress Syndrome (PTSS).

Multicenter observational cohort study.

Nine Portuguese intensive care units, as part of a multicenter study.

Between January and June 2005, 1,174 patients were admitted across the nine intensive care units. Two hundred thirty-nine patients were excluded, 14 with < 18 yrs old and 225 with a length of intensive care stay < or = 48 hrs. Thus a total of 935 patients were included in the study. One hundred ninety (20%) patients died in the intensive care unit, 90 (12%) patients died on the ward (30% in-hospital mortality rate), and another 56 (9%) died in the next 6 months after intensive care unit discharge.

From the 599 survivors at 6 months, 313 patients answered the questionnaires (52% response rate). From the 313 respondents, 58% (n = 183) were men, median age was 59. The median Simplified Acute Physiology Score II was 37, median intensive care unit length of stay was 8 days, 57% (n = 177) of the patients were admitted for medical reasons. Forty percent (n = 116) of the respondents did not remember their admission to hospital, 48% (n = 142) did not remember the time in the hospital before intensive care unit admission, 73% (n = 220) had factual memories and 39% (n = 118) had delusional memories. Twenty-three percent (n = 66) stated that they had had intrusive memories. A higher number of "adverse" experiences were significantly associated with a higher PTSS-14 score. Eighteen percent (n = 54) of patients had a PTSS-14 score > 49, indicating a higher risk of developing posttraumatic stress disorder. A PTSS-14 score > 49 was significantly associated with not remembering the hospital stay before intensive care unit admission.

Amnesia for the early period of critical illness (early amnesia) was positively associated with the level of posttraumatic stress disorder-related symptoms, which may be a proxy for severity of disease at the time of intensive care unit admission.