Table 3.
Baseline cognitive impairment/dementia as independent risk factor for delirium from predictive models
| Study (year) | Population | Cognitive baseline | Delirium measure | Mean age (years) | % delirium | Effect size (adjusted) (95% CI) |
|---|---|---|---|---|---|---|
| Kennedy (2014)21 | Emergency department, age ≥ 65 years (n=700) | Documented dementia by chart | Prevalent delirium by CAM | 77 | 9% | OR 4.3 (2.2 to 8.5) |
| Koster (2013)22 | Elective cardiac surgery, age ≥ 70 years (n=300) | MMSE < 23 | DOSS | 74 | 17% | OR 4.5 (1.9 to 13) |
| Moerman (2012)23 | Acute hip fracture, age ≥ 65 years (n=378) | Clinical diagnosis of dementia | Prevalent delirium by DSM-IV | 84 | 27% | OR 2.8 (1.7 to 4.6) |
| Bo (2009)24 | Patients age ≥ 70 years admitted to medical or geriatric ward (n=252) | SPMSQ for presence and severity of cognitive impairment | Incident delirium by CAM | 82 | 11% | RR 2.1 (1.6 to 2.6) |
| Rudolph (2009)25 | Planned cardiac surgery, age ≥60 years (development n=122; validation=109). | Pre-operative MMSE ≤ 23 | Incident delirium by CAM | 75 | 44% | RR 1.3 (1.0 to 1.7) |
| Kalisvaart (2006)26 | Elective hip surgery, age ≥ 70 years (n=603) | Pre-operative MMSE <24 | Postoperative delirium by DSM-IV and CAM | 78 | 12% | RR 5.5 (3.6 to 8.6) |
| Wilson (2005)27 | Patients aged ≥ 75 years admitted to an acute medical ward (n=100) | IQCODE to establish presence of cognitive change over time | Incident delirium by DSM-III | 85 | 12% | OR 3.2 (1.2 to 9.0) |
| O’Keeffe (1996)28 | Acute medical admissions to geriatric medicine unit (n=225) | Clinical diagnosis of dementia or BDRS ≥4 | Incident delirium by DSM-III | 82 | 28% | OR 4.8 (2.0 to 11.6) |
| Marcantonio (1994)29 | Elective surgical admissions, age ≥ 50 years (n=1341) | TICS <30 | Post-operative delirium by CAM | 68 | 9% | OR 4.2 (2.4 to 7.3) |
| Pompei (1994)30 | Acute hospital medical and surgical admissions, age ≥ 65 years with no delirium (development n=432; validation n=323) | MMSE < 24 (education adjusted) | Incident delirium by DSM-III-R | 74 | 15% | OR 3.6 (2.1 to 6.2) |
| Inouye (1993)31 | Acute hospital medical admissions, age ≥ 70 years with no dementia or delirium (development n=107; validation n=174) | MMSE < 24 on admission | Incident delirium by CAM | 79 | 25% | RR 2.8 (1.2 to 6.7) |
BDRS Blessed Dementia Rating Scale; CAM Confusion Assessment Method; DOSS Delirium Observation Screening Scale; IQCODE Informant Questionnaire for Cognitive Decline in the Elderly; MMSE Mini-Mental State Examination; OR odds ratio; RR relative risk; SPMSQ Short Portable Mental Status Questionnaire; TICS Telephone Interview for Cognitive Status.