Delirium increases the risk of mortality during an acute hospital admission. Full syndromal delirium (FSD) is associated with greatest risk and subsyndromal delirium (SSD) is associated with intermediate risk, compared to patients with no delirium – suggesting a dose-response relationship. It is not clear how individual diagnostic symptoms of delirium influence the association with mortality. Our objectives were to measure the prevalence of FSD and SSD, and assess the effect that FSD, SSD and individual symptoms of delirium (from the Confusion Assessment Method-short version (s-CAM)) have on mortality rates.
Exploratory analysis of a prospective cohort (aged ≥70 years) with acute (unplanned) medical admission (4/6/2007–4/11/2007). The outcome was mortality (data censored 6/10/2011). The principal exposures were FSD and SSD compared to no delirium (as measured by the CAM), along with individual delirium symptoms on the CAM. Cox regression was used to estimate the impact FSD and SSD and individual CAM items had on mortality.
The cohort (n = 610) mean age was 83 (SD 7); 59% were female. On admission, 11% had FSD and 33% had SSD. Of the key diagnostic symptoms for delirium, 17% acute onset, 19% inattention, 17% disorganised thinking and 17% altered level of consciousness. Unadjusted analysis found FSD had an increased hazard ratio (HR) of 2.31 (95% CI 1.71, 3.12), for SSD the HR was 1.26 (1.00, 1.59). Adjusted analysis remained significant for FSD (1.55 95% CI 1.10, 2.18) but nonsignificant for SSD (HR = 0.92 95% CI 0.70, 1.19). Two CAM items were significantly associated with mortality following adjustment: acute onset and disorganised thinking.
We observed a dose-response relationship between mortality and delirium, FSD had the greatest risk and SSD having intermediate risk. The CAM items “acute-onset” and “disorganised thinking” drove the associations observed. Clinically, this highlights the necessity of identifying individual symptoms of delirium.
American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. Washington DC: American Psychiatric Association; 1994.
Lindesay J, Rockwood K, Rolfson D. The epidemiology of delirium. In: Lindesay J, Rockwood K, Macdonald A, editors. Delirium in Old Age. Oxford: Oxford University Press; 2002. p. 27–50.
Inouye SK. The Short Confusion Assessment Method (Short CAM): training manual and coding guide. Boston: Hospital Elder Life Program; 2014.
Waterlow J. Pressure sores: a risk assessment card. Nurs Times. 1985;81(48):49–55. PubMed
Man SY, Chan KM, Wong FY, Wong KY, Yim CL, Mak PS, Kam CW, Lau CC, Lau FL, Graham CA, et al. Evaluation of the performance of a modified Acute Physiology and Chronic Health Evaluation (APACHE II) scoring system for critically ill patients in emergency departments in Hong Kong. Resuscitation. 2007;74(2):259–65. CrossRefPubMed
Reisberg B, Sclan SG, Franssen E, Kluger A, Ferris S. Dementia staging in chronic care populations. Alzheimer Dis Assoc Disord. 1994;8(Suppl 1):S188–205. PubMed
Dani M, Owen LH, Jackson TA, Rockwood K, Sampson EL, Davis D. Delirium, frailty and mortality: interactions in a prospective study of hospitalized older people. J Gerontol A Biol Sci Med Sci. 2017. https://doi.org/10.1093/gerona/glx214.
- Key components of the delirium syndrome and mortality: greater impact of acute change and disorganised thinking in a prospective cohort study
R. A. Diwell
E. L. Sampson
- BioMed Central
Neu im Fachgebiet Innere Medizin
Meistgelesene Bücher aus der Inneren Medizin
e.Med Kampagnen-Visual, Mail Icon II