Delirium – an overlooked complication of stroke

By Kateriine Orav, Department of Neurology, North Estonia Medical Center, Estonia

Most doctors have encountered late night negotiations with patients who suddenly discover themselves in a bizarre reality and are convinced the only thing to do is escape. Or patients who believe the nasogastric tube is a sort of evil creature that needs to be removed. And quite often we fail to comprehend the impact and distress this condition is having on the patient. Stroke patients are a unique group of patients who can develop delirium because underlying the acute brain dysfunction characteristic of this disorder is an actual structural brain disease. Delirium has received unproportionally little attention in stroke care. Even though it is rather common, affecting approximately 1 in 4 people.1

Detection of delirium is important for several reasons. Firstly, stroke patients who develop delirium have worse outcomes: higher inpatient and long-term mortality, longer hospitalizations and a greater degree of dependency after discharge.2 In addition, the experience of delirium can be very traumatic for patients and many studies have shown an increased rate of depression and post-traumatic stress disorder after ICU delirium,3 but this has not been adequately studied in stroke patients.

However, the diagnosis of delirium is often quite difficult and even more so in stroke patients, due to prevalent language disorders, neglect, mood disturbances and cognitive impairment. Hyperactive delirium often attracts the attention of medical personnel but is 3 times less common than the hypoactive delirium subtype, which can be easily missed when the patient is perceived as cooperative and exhibits few behavioral problems.4

There are many factors that can increase the risk of developing post-stroke delirium. It is more common in patients with advanced age, worse pre-stroke function and cognitive impairment, more severe stroke, previous depression, use of certain medications, comorbid disorders and co-occurring infection.1,4 In addition patients with visio-spatial neglect (which is more commonly associated with right hemispheric strokes) and any kind of visual disturbances (poor vision pre-stroke, hemianopsia) have an increased risk of delirium.4,5

Early detection of delirium is crucial to tailor specific interventions, however there is much uncertainty about which tools to use in stroke patients. The 4-Assessment Test for delirium (4AT) and the Confusion Assessment Method-Intensive Care Unit (CAM-ICU) have been studied most and both have a high sensitivity and specificity.6 Without structured assessment and often serial observations delirium can be missed, especially the hypoactive subtype.7 The majority of delirium is detected on the first day of admission and the remainder within the next 5 days,8 therefore ideally patients should be assessed for delirium regularly during at least this time period.

Aiming to prevent delirium and minimizing its negative consequences should be a priority in stroke care. There is strong evidence supporting multi-component interventions to prevent delirium in patients hospitalized in medical and surgical wards and less robust evidence that they can reduce the severity of delirium.9 Several guidelines are dedicated to this topic in the non-stroke population.7 However, there is scarce evidence about the efficacy of delirium prevention interventions in stroke patients and not all interventions can be easily applied in this cohort. A few studies have shown that delirium prevention protocols were able to decrease delirium incidence and severity in stroke patients,10 as well as reduce length of hospitalization in a neuroscience ward.11 Whether the reduction in delirium incidence and length would also translate into better functional outcome in stroke patients remains to be answered.

Delirium can also be considered as a marker of quality of care and delirium incidence seems to have decreased with multidisciplinary care offered in stroke units that partially overlaps with multicomponent interventions proven to reduce delirium incidence.1 Therefore, delirium prevention, screening and management should be part of the daily routine in stroke care.  Delirium prevention protocols that are better adjusted for stroke patients with different deficits (including cognition and language) will hopefully be available in the future.

References:

  1. Shaw RC, Walker G, Elliott E, Quinn TJ. Occurrence Rate of Delirium in Acute Stroke Settings Systematic Review and Meta-Analysis. Stroke. 2019;50:3028-3036
  2. Shi Q, Presutti R, Selchen D, Saposnik G. Delirium in Acute Stroke. A Systematic Review and Meta-Analysis. Stroke. 2012;43:645-649.
  3. Righy C, Rosa RG, da Silva RTA, et al.Prevalence of post-traumatic stress disorder symptoms in adult critical care survivors: a systematic review and meta-analysis. Crit Care2019;23:213
  4. Pasinska P, Kowalska K, Klimiec E, et al. Poststroke Delirium Clinical Motor Subtypes: The PRospective Observational POLIsh Study (PROPOLIS). J Neurol2018;265:863–870
  5. Pasinska P, Kowalska K, Klimiec E, et al.Poststroke Delirium Clinical Motor Subtypes: The PRospective Observational POLIsh Study (PROPOLIS). J Neuropsychiatry Clin Neurosci 2019:31:104-111
  6. Mansutti I, Saiani L, Palese A. Detecting delirium in patients with acute stroke: a systematic review of test accuracy. BMC Neurology 2019;19:310
  7. Klimiec E, Dziedzic T, Kowalska K, et al. Knowns and Unknowns About Delirium in Stroke: A Review. Cogn Behav Neurol. 2016;29:4
  8. Shaw R, Drozdowska B, Taylor-Rowan M, et al. Delirium in an Acute Stroke Setting, Occurrence, and Risk Factors. Stroke. 2019;50:00-00.
  9. Siddiqi N, Harrison JK, Clegg A, et al. Interventions for preventing delirium in hospitalised non-ICU patients. Cochrane Database of Systematic Reviews 2016;3. Art. No.: CD005563.
  10. Song J, Lee M, Jung D. The Effects of Delirium Prevention Guidelines on Elderly Stroke Patients. Clinical Nursing Research 2018;27(8):967-983
  11. Brown EG, Josephson A, Anderson N, et al. Evaluation of a multicomponent pathway to address inpatient delirium on a neurosciences ward. BMC Health Serv Res 2018;18:106