Neuropsychological outcome after cardiac arrest: results from a sub-study of the targeted hypothermia versus targeted normothermia after out-of-hospital cardiac arrest (TTM2) trial

TY - JOUR

T1 - Neuropsychological outcome after cardiac arrest

T2 - results from a sub-study of the targeted hypothermia versus targeted normothermia after out-of-hospital cardiac arrest (TTM2) trial

AU - Blennow Nordström, Erik

AU - Vestberg, Susanna

AU - Evald, Lars

AU - Mion, Marco

AU - Segerström, Magnus

AU - Ullén, Susann

AU - Bro-Jeppesen, John

AU - Friberg, Hans

AU - Heimburg, Katarina

AU - Grejs, Anders M.

AU - Keeble, Thomas R.

AU - Kirkegaard, Hans

AU - Ljung, Hanna

AU - Rose, Sofia

AU - Wise, Matthew P.

AU - Rylander, Christian

AU - Undén, Johan

AU - Nielsen, Niklas

AU - Cronberg, Tobias

AU - Lilja, Gisela

N1 - Publisher Copyright: © 2023, BioMed Central Ltd., part of Springer Nature.

PY - 2023/12

Y1 - 2023/12

N2 - Background: Cognitive impairment is common following out-of-hospital cardiac arrest (OHCA), but the nature of the impairment is poorly understood. Our objective was to describe cognitive impairment in OHCA survivors, with the hypothesis that OHCA survivors would perform significantly worse on neuropsychological tests of cognition than controls with acute myocardial infarction (MI). Another aim was to investigate the relationship between cognitive performance and the associated factors of emotional problems, fatigue, insomnia, and cardiovascular risk factors following OHCA. Methods: This was a prospective case–control sub-study of The Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial. Eight of 61 TTM2-sites in Sweden, Denmark, and the United Kingdom included adults with OHCA of presumed cardiac or unknown cause. A matched non-arrest control group with acute MI was recruited. At approximately 7 months post-event, we administered an extensive neuropsychological test battery and questionnaires on anxiety, depression, fatigue, and insomnia, and collected information on the cardiovascular risk factors hypertension and diabetes. Results: Of 184 eligible OHCA survivors, 108 were included, with 92 MI controls enrolled. Amongst OHCA survivors, 29% performed z-score ≤ − 1 (at least borderline–mild impairment) in ≥ 2 cognitive domains, 14% performed z-score ≤ − 2 (major impairment) in ≥ 1 cognitive domain while 54% performed without impairment in any domain. Impairment was most pronounced in episodic memory, executive functions, and processing speed. OHCA survivors performed significantly worse than MI controls in episodic memory (mean difference, MD = − 0.37, 95% confidence intervals [− 0.61, − 0.12]), verbal (MD = − 0.34 [− 0.62, − 0.07]), and visual/constructive functions (MD = − 0.26 [− 0.47, − 0.04]) on linear regressions adjusted for educational attainment and sex. When additionally adjusting for anxiety, depression, fatigue, insomnia, hypertension, and diabetes, executive functions (MD = − 0.44 [− 0.82, − 0.06]) were also worse following OHCA. Diabetes, symptoms of anxiety, depression, and fatigue were significantly associated with worse cognitive performance. Conclusions: In our study population, cognitive impairment was generally mild following OHCA. OHCA survivors performed worse than MI controls in 3 of 6 domains. These results support current guidelines that a post-OHCA follow-up service should screen for cognitive impairment, emotional problems, and fatigue. Trial registration : ClinicalTrials.gov, NCT03543371. Registered 1 June 2018.

AB - Background: Cognitive impairment is common following out-of-hospital cardiac arrest (OHCA), but the nature of the impairment is poorly understood. Our objective was to describe cognitive impairment in OHCA survivors, with the hypothesis that OHCA survivors would perform significantly worse on neuropsychological tests of cognition than controls with acute myocardial infarction (MI). Another aim was to investigate the relationship between cognitive performance and the associated factors of emotional problems, fatigue, insomnia, and cardiovascular risk factors following OHCA. Methods: This was a prospective case–control sub-study of The Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial. Eight of 61 TTM2-sites in Sweden, Denmark, and the United Kingdom included adults with OHCA of presumed cardiac or unknown cause. A matched non-arrest control group with acute MI was recruited. At approximately 7 months post-event, we administered an extensive neuropsychological test battery and questionnaires on anxiety, depression, fatigue, and insomnia, and collected information on the cardiovascular risk factors hypertension and diabetes. Results: Of 184 eligible OHCA survivors, 108 were included, with 92 MI controls enrolled. Amongst OHCA survivors, 29% performed z-score ≤ − 1 (at least borderline–mild impairment) in ≥ 2 cognitive domains, 14% performed z-score ≤ − 2 (major impairment) in ≥ 1 cognitive domain while 54% performed without impairment in any domain. Impairment was most pronounced in episodic memory, executive functions, and processing speed. OHCA survivors performed significantly worse than MI controls in episodic memory (mean difference, MD = − 0.37, 95% confidence intervals [− 0.61, − 0.12]), verbal (MD = − 0.34 [− 0.62, − 0.07]), and visual/constructive functions (MD = − 0.26 [− 0.47, − 0.04]) on linear regressions adjusted for educational attainment and sex. When additionally adjusting for anxiety, depression, fatigue, insomnia, hypertension, and diabetes, executive functions (MD = − 0.44 [− 0.82, − 0.06]) were also worse following OHCA. Diabetes, symptoms of anxiety, depression, and fatigue were significantly associated with worse cognitive performance. Conclusions: In our study population, cognitive impairment was generally mild following OHCA. OHCA survivors performed worse than MI controls in 3 of 6 domains. These results support current guidelines that a post-OHCA follow-up service should screen for cognitive impairment, emotional problems, and fatigue. Trial registration : ClinicalTrials.gov, NCT03543371. Registered 1 June 2018.

KW - Cardiovascular disease

KW - Cognitive impairment

KW - Heart arrest

KW - Hypoxic-ischemic encephalopathy

KW - Myocardial infarction

KW - Outcome

UR - http://www.scopus.com/inward/record.url?scp=85168740704&partnerID=8YFLogxK

U2 - 10.1186/s13054-023-04617-0

DO - 10.1186/s13054-023-04617-0

M3 - Journal article

C2 - 37633944

AN - SCOPUS:85168740704

SN - 1364-8535

VL - 27

JO - Critical Care

JF - Critical Care

IS - 1

M1 - 328

ER -