Clarifying confusion: the confusion assessment method. A new method for detection of delirium

OBJECTIVE: To develop and validate a new standardized confusion assessment method (CAM) that enables nonpsychiatric clinicians to detect delirium quickly in high-risk settings. DESIGN: Prospective validation study. SETTING: Conducted in general medicine wards and in an outpatient geriatric assessment center at Yale University (site 1) and in general medicine wards at the University of Chicago (site 2). PATIENTS: The study included 56 subjects, ranging in age from 65 to 98 years. At site 1, 10 patients with and 20 without delirium participated; at site 2, 16 patients with and 10 without delirium participated. MEASUREMENTS AND MAIN RESULTS: An expert panel developed the CAM through a consensus building process. The CAM instrument, which can be completed in less than 5 minutes, consists of nine operationalized criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R). An a priori hypothesis was established for the diagnostic value of four criteria: acute onset and fluctuating course, inattention, disorganized thinking, and altered level of consciousness. The CAM algorithm for diagnosis of delirium required the presence of both the first and the second criteria and of either the third or the fourth criterion. At both sites, the diagnoses made by the CAM were concurrently validated against the diagnoses made by psychiatrists. At sites 1 and 2 values for sensitivity were 100% and 94%, respectively; values for specificity were 95% and 90%; values for positive predictive accuracy were 91% and 94%; and values for negative predictive accuracy were 100% and 90%. The CAM algorithm had the highest predictive accuracy for all possible combinations of the nine features of delirium. The CAM was shown to have convergent agreement with four other mental status tests, including the Mini-Mental State Examination. The interobserver reliability of the CAM was high (kappa = 0.81 - 1.0). CONCLUSIONS: The CAM is sensitive, specific, reliable, and easy to use for identification of delirium.     

Delirium in elderly patients hospitalized in internal medicine wards

A prospective observational study was conducted to evaluate the impact of delirium on geriatric inpatients in internal medical wards and to identify predisposing factors for the development of delirium. The study included all patients aged 65 years and older, who were consecutively admitted to the internal medicine wards of two public hospitals in Florence, Italy. On admission, 29 baseline risk factors were examined, cognitive impairment was evaluated by Short Portable Mental Status Questionnaire, and prevalent delirium cases were diagnosed by Confusion Assessment Method (CAM). Enrolled patients were evaluated daily with CAM to detect incident delirium cases. Among the 560 included patients, 19 (3 %) had delirium on admission (prevalent) and 44 (8 %) developed delirium during hospitalization (incident). Prevalent delirium cases were excluded from the statistical analysis. Incident delirium was associated with increased length of hospital stay (p < 0.01) and institutionalization (p < 0.01, OR 3.026). Multivariate analysis found that cognitive impairment on admission (p < 0.0002), diabetes (p < 0.05, OR 1.936), chronic kidney failure (p < 0.05, OR 2.078) and male gender (p < 0.05, OR 2.178) was significantly associated with the development of delirium during hospitalization. Results show that delirium impact is relevant to older patients hospitalized in internal medicine wards. The present study confirms cognitive impairment as a risk factor for incident delirium. The cognitive evaluation proved to be an important instrument to improve identification of patients at high risk for delirium. In this context, our study may contribute to improve application of preventive strategies.     

Pre-operative mild cognitive dysfunction predicts risk for post-operative delirium after elective cardiac surgery

BACKGROUND AND AIMS: To identify pre-operative risk factors for delirium in patients undergoing elective cardiac surgery, using clearly defined diagnostic criteria for delirium, and a thorough clinical assessment. METHODS: The incidence of post-operative delirium in 107 patients >or=60 years undergoing elective cardiac surgery was calculated. None of the patients included suffered from dementia. Pre-operative cognitive function in all patients was assessed using the Mini Mental State Examination (MMSE) and post-operative delirium was diagnosed using the Confusion Assessment Method (CAM). Post-operative clinical and cognitive assessments were carried out for all patients. RESULTS: Twenty-five patients (23.4%) developed delirium post-operatively. Clinical parameters, including age, gender, co-morbidities, medications, and peri-operative parameters, were similar in patients with and without post-operative delirium. Patients with pre-operative subjective memory complaints and lower MMSE scores, undergoing valve operation or valve + coronary artery bypass grafting (CABG), exhibited an increased risk of developing post-operative delirium. Additionally, delirious patients had a significant decline in post-operative MMSE score compared with the non-delirious ones. CONCLUSIONS: The main pre-operative risk factors for post-operative delirium after elective cardiac operations were subjective memory complaints, mild cognitive impairment, and type of cardiac surgery, such as valve procedures. This study suggests that cognitive evaluation should be included in pre-operative assessment.     

Delirium among elderly general medical patients in a New Zealand hospital

Background: Overseas studies suggest that delirium is a common and serious health problem of hospitalized elderly. There is very little information in New Zealand. Aims: To study prospectively the frequency and effect of delirium on a cohort of elderly general medical patients. Methods: Over 2 months, 317 patients were admitted to general medical wards; 70% were aged 65 years and above. These patients were screened for delirium. Comparisons were made between the delirious and non‐delirious patients. Results: Fifty‐six of the 216 patients screened had delirium. The prevalence and incidence of delirium were 23.4 and 5.7%, respectively. Thirty‐one per cent of delirious patients had a previous history of dementia; 48% of delirious patients had multiple precipitants, most commonly infections. Delirium was associated with higher complication rates – 94 versus 39% in the non‐delirious patients – and a doubling in the length of hospital stay. Over 50% of delirious patients required increased supports on discharge with a general trend towards higher frequency of institutionalization. The presence of delirium was associated with increased use of neuroleptic medications, special nursing care, cot sides and restraints. A non‐significant trend towards increased mortality was seen in the delirious group. Conclusions: Delirium is a common health problem in elderly patients, associated with multiple adverse outcomes. This study highlighted the prognostic importance of diagnosing delirium. Recommendations included improved health professional education, development of guidelines including rational use of neuroleptic medication and measures to improve follow up for these patients.     

Seasonal variation in the incidence of delirium among the patients of a geriatric hospital

Delirium syndrome is common in the hospitalized elderly population. However, data on its numerous etiological factors are scarce. Clinical observations suggest that delirium incidence could be related to seasonality. In order to evaluate the seasonal influence on the incidence of delirium syndrome among the patients of a geriatric hospital, we performed a retrospective study reviewing the medical records of 5218 patients aged 65 years and older, who were hospitalized in three medical wards between the years 1991 and 1997. The diagnoses of delirium were made according to ICD-9-CM. Of the 4929 subjects enrolled, 3548 (72%) were referred for assessment to the psychiatric or neurologic specialist, because of acute changes in their mental or behavioral status. Of those patients, 312 (6.3%) were diagnosed with delirium at admission, and 234 (4.7%) developed delirium during their hospitalization. Statistical analysis of incidence revealed a seasonal variation, with higher rates in the winter than in the summer months (P<0.001). This study suggests a seasonal influence on delirium syndrome incidence and a possible etiological relation with seasonal factors like the light -dark cycle.     

Validating an Australian version of the Time and Change Test: A screening test for cognitive impairment

Objectives: The ‘Time and Change Test’– a brief cognitive screening test has been validated in several countries to assess cognitive impairment. We attempted to validate an Australian version of the test among hospital inpatients. Methods: One hundred and thirty patients consented to participate in the study. They underwent an assessment for a Diagnostic and Statistical Manual of Mental Disorders (DSM IV) diagnosis for dementia or delirium, the Mini‐Mental State Examination and the Time and Change Test. Results: The Time and Change Test had a sensitivity of 44% (95% CI; 23%, 66%) and a specificity of 90% (**80%, 96%) for a DSM IV diagnosis of dementia or delirium. Conclusions: This version of the Time and Change was less sensitive than other versions. The sensitivity of the test came from the change component, and reduced complexity of this task may account for this finding. We recommend study of a more complex change‐making test as a screening tool for cognitive impairment.     

Delirium in a sub-intensive care unit for the elderly: occurrence and risk factors

BACKGROUND AND AIMS: The objective was to study occurrence and risk factors of delirium in a new model of care, the Sub-Intensive Care Unit for the elderly (SICU), which is a level of care between that offered by ordinary wards and intensive care. METHODS: A prospective observational study of 401 consecutively admitted patients, 60+ years, in a four-bed SICU in the geriatric ward of a general hospital. Delirium was detected by the Confusion Assessment Method (CAM) at admission (prevalent) and during SICU stay (incident). Impaired function (Barthel Index) and/or IADL two weeks prior to admission identified disability, and additional Mini-Mental State Examination (MMSE) <18 at discharge identified probable dementia. RESULTS: Delirium was detected in 117 patients (29.2%). Of these 62 (15.5%) had delirium at admission and a further 55 developed delirium during their time in the SICU. Delirium occurred in 19 (11.4%) of the "robust" (no dementia or disability), 28 (24.1%) of the disabled and 70 (58.4%) of the demented patients (p<0.001). Prevalent delirium was found in 8 (4.8%), 11 (9.5%) and 43 (36.1%) (p<0.001) and incident in 11 (6.6%), 17 (14.7%) and 27 (22.7%) (p<0.001) of the robust, disabled, and demented patients respectively. Heavy alcohol use, maximum intake of 7 or more drugs, and the use of a bladder catheter were independently associated with delirium. CONCLUSIONS: Delirium was common in the SICU, and patients with probable dementia had the highest risk. They tended to have delirium at admission, whereas patients without dementia, although less at risk, were more prone to developing delirium during their stay in the SICU.     

Delirium in elderly general medical inpatients: a prospective study

Background: More than 49% of all US hospital days are spent caring for patients with delirium. There are few Australian data on this important condition. The aim of the study was to determine the prevalence and incidence of delirium in older medical inpatients in a metropolitan teaching hospital, the incidence of known risk factors and current practice in identifying and managing patients at risk of this condition. Methods: Patients aged 65 years or more, and admitted to a general medical unit, were eligible for study inclusion. Participants were screened with an Abbreviated Mental Test Score (AMTS) and chart review. Confusion Assessment Method was used to diagnose delirium if confusion was documented or AMTS <8. Barthel Index (BI), demographics, delirium risk factors and management were recorded. Results: Prevalent delirium was diagnosed in 19 of 104 (18%) and incident delirium in 2 of 85 (2%) participants. Pre‐existing cognitive impairment and admission AMTS <8 were strongly associated with prevalent delirium (P‐values <0.01). Age >80 years, Barthel Index ≤50, use of high‐risk medications and electrolyte disturbance were also associated with prevalent delirium. Prevalent delirium was not recognized by the treating unit in 4 of 19 cases (21%). Five of 104 (4.8%) of participants had a formal cognitive assessment on admission. One of 19 patients (5.3%) with prevalent delirium had an orientation device in their room. Conclusion: Pre‐existing cognitive impairment and admission AMTS are strong predictors of delirium. Despite this, formal cognitive assessment is not routinely carried out in elderly medical patients. Recognition of delirium may be improved by routine cognitive assessment in elderly medical patients.     

The effect of mental status screening on the care of elderly emergency department patients

STUDY OBJECTIVES: We determine the effect of screening examinations for mental status impairment on the care of elderly patients in the emergency department and prospectively assess recognition of mental status impairment by emergency physicians. METHODS: We performed a prospective cross-sectional study. Patients were 70 years of age or older and presented to an urban teaching hospital ED over a 17-month period. Mental status impairment screening comprised the Orientation Memory Concentration examination for cognitive impairment and the Confusion Assessment Method for delirium. Emergency physicians who were blinded to the patient's screening results were interviewed to assess recognition of mental status impairment, dispositions, and referrals. Results of mental status impairment screens were then given to emergency physicians, and emergency physicians were reinterviewed regarding any change in care. RESULTS: Two hundred seventy-one of the 327 eligible patients were enrolled. Seventy-four (27%; 95% confidence interval [CI] 22% to 33%) patients had impaired mental status. Nineteen (7%; 95% CI 4% to 11%) had delirium, and 55 (20%; 95% CI 16% to 25%) had cognitive impairment without delirium. Mental status impairment was recognized in only 28 (38%; 95% CI 27% to 50%) of 74 patients: 3 (16%; 95% CI 3% to 40%) of 19 with delirium and 25 (46%; 95% CI 32% to 59%) of 55 with cognitive impairment without delirium. Emergency physicians altered management in none of the study patients on the basis of survey results. Five (26%; 95% CI 9% to 51%) of the 19 patients with delirium were discharged to home. Of these 5 patients discharged to home with unrecognized delirium, 1 presented with fall, 2 returned 3 days later and required hospitalization, and 1 with a history of colon cancer was given a new diagnosis of metastatic disease 4 days after the initial ED visit. CONCLUSION: Mental status impairment is highly prevalent in older ED patients. There is a lack of recognition by emergency physicians of mental status impairment in this group. Screening tools for mental status impairment in the ED did not substantially alter the care of elderly patients with mental status impairment.     

Examining the reliability and validity of the Hebrew version of the Mini Mental State Examination

The Mini Mental State Examination is used worldwide for the screening and diagnosis of dementia. The aim of the present study was to examine the reliability and validity of the Hebrew version of the Mini Mental State Examination. The Hebrew version of the Mini Mental State Examination was administered to 36 demented and 19 non-demented elderly persons. Test-retest reliability scores were calculated as exact agreement rates, and ranged from good to excellent for all the items. Strong convergent validity, as measured by the correlation between the MMSE and the CAM-COG (r = 0.94), was found. Good predictive value was observed as over three-quarters of the participants were correctly classified as demented or non-demented. The Hebrew version of the MMSE was found to be a useful and valid instrument for the determination of dementia in the elderly population.     

Is anaemia a risk factor for delirium in an acute geriatric population?

BACKGROUND/OBJECTIVE: Delirium is a common clinical problem in elderly patients. We aim to investigate whether anaemia is a risk factor for delirium in a hospitalized geriatric population. METHODS: During a 5-month prospective study, we investigated 190 elderly patients aged 70 years and older with a baseline Mini-Mental State Examination (short version), Confusion Assessment Method, demographic, clinical and laboratory data. RESULTS: Thirty-four patients were identified as delirious and 95 as anaemic according to the WHO criteria. Stepwise logistic regression revealed that anaemia (haemoglobin level <12 g/l in women and <13 g/l in men), male sex and a diagnosis of dementia were independent risk factors for delirium in the total study group. After adjustment for sex, age, diagnosis of dementia and dehydration, the odds ratio (OR) for anaemia (2.4; 95 CI = 1.02-5.54) remained significantly associated with delirium. When the study population was classified in groups according to sex, anaemia remained a significant risk factor for delirium in men (OR = 3.7; 95% CI = 1.03-15.6) after adjustment for the multiple variables but not in women (OR = 1.54; 95% CI = 0.48-4.9). When the haemoglobin levels were stratified into sex-specific quartiles, the adjusted OR for delirium for men with a haemoglobin level less than 11.1 g/dl was 13.1 (95% CI = 1.17-146). CONCLUSION: Anaemia is an independent risk factor for delirium and adds valuable information to previously validated predictive models in men but not in women and lower haemoglobin levels were associated with higher risk levels.     

Les syndromes confusionnels du sujet âgé hospitalisé: polymorphisme sémiologique et évolutif. Étude prospective de 183 patients

Using explicit criteria contained in the DSM III R, we collected in a prospective cohort study clinical features, outcome and risk factors from two cohorts of delirium in hospitalized elderly patients: 138 hospitalized in geriatric department and 45 patients admitted to an acute and comprehensive care hospital. The clinical features were assessed using a quantitative scale (developed by Derouesné). Delirium was unrecognized or misdiagnosed by physicians in 34% of the cases. The onset was known only two thirds of cases. The incidence of hyperactive type, prolonged hospital stay, poor outcomes (persistent delirium leading up to dementia) were highest in subjects admitted in comprehensive hospital. The etiology of delirium is complex and multifactorial. An underlying cause was identified in 80% of patients. The length or the worsening of delirium was significantly higher in patients with psychiatric or dementia comorbidity (OR: 0.2; IC 95%: 0.1–0.5). The prognosis was better in patients without psychoactive medications (OR: 0.2; IC 95%: 0.1–0.4) or with metabolic abnormalities or acute diseases and disorders (OR: 3.3; IC 95%: 1.5–7.6). The predisposing factors to the development of dementia were prior use of psychoactive medications and signs of prior cognitive impairment. This article suggests delirium in elderly patients is associated with several outcomes. The prognosis should be improved at admission by specific scale and an evaluation of predisposing and precipitating factors.     

A chart-based method for identification of delirium: validation compared with interviewer ratings using the confusion assessment method

OBJECTIVES: To validate a chart-based method for identification of delirium and compare it with direct interviewer assessment using the Confusion Assessment Method (CAM). DESIGN: Prospective validation study. SETTING: Teaching hospital. PARTICIPANTS: Nine hundred nineteen older hospitalized patients. MEASUREMENTS: A chart-based instrument for identification of delirium was created and compared with the reference standard interviewer ratings, which used direct cognitive assessment to complete the CAM for delirium. Trained nurse chart abstractors were blinded to all interview data, including cognitive and CAM ratings. Factors influencing the correct identification of delirium in the chart were examined. RESULTS: Delirium was present in 115 (12.5%) patients according to the CAM. Sensitivity of the chart-based instrument was 74%, specificity was 83%, and likelihood ratio for a positive result was 4.4. Overall agreement between chart and interviewer ratings was 82%, kappa=0.41. By contrast, using International Classification of Diseases, Ninth Revision, Clinical Modification, administrative codes, the sensitivity for delirium was 3%, and specificity was 99%. Independent factors associated with incorrect chart identification of delirium were dementia, severe illness, and high baseline delirium risk. With all three factors present, the chart instrument was three times more likely to identify patients incorrectly than with none of the factors present. CONCLUSION: A chart-based instrument for delirium, which should be useful for patient safety and quality-improvement programs in older persons, was validated. Because of potential misclassification, the chart-based instrument is not recommended for individual patient care or diagnostic purposes.     

Delirium superimposed on dementia predicts 12-month survival in elderly patients discharged from a postacute rehabilitation facility

BACKGROUND: Delirium superimposed on dementia (DSD) is highly prevalent and associated with high mortality among hospitalized elderly patients, yet little is known about the effect of DSD on midterm mortality. The purpose of this study was to assess 12-month survival in patients with DSD and matched groups with dementia alone, delirium alone, or neither delirium nor dementia. METHODS: Among 1278 consecutively admitted elderly participants (aged > or =65 years) to our Rehabilitation Unit between January 2002 and May 2005, four matched samples of 47 participants each (DSD, dementia alone, delirium alone, or neither delirium nor dementia) were selected. Matching was based on age, gender, and reason for admission. Postdischarge 12-month survival was assessed in the four groups with Kaplan-Meyer analysis and compared with Cox proportional hazard regression models adjusted for confounders. RESULTS: Survival was significantly lower for DSD patients than for the other three groups. After adjustment for comorbidity and Barthel Index score before admission, patients with DSD had significantly higher mortality (hazard ratio, 2.3; 95% confidence interval, 1.1-5.5; p =.04) than did patients with neither delirium nor dementia. CONCLUSIONS: Demented patients who experienced delirium during hospitalization had a more than twofold increased risk of mortality in the 12 months following discharge than did patients with dementia alone, with delirium alone, or with neither dementia nor delirium.     

Postoperative delirium in old patients with femoral neck fracture: a randomized intervention study

BACKGROUND AND AIMS: Delirium is a common postoperative complication in elderly patients which has a serious impact on outcome in terms of morbidity and costs. We examined whether a postoperative multi-factorial intervention program can reduce delirium and improve outcome in patients with femoral neck fractures. METHODS: One hundred and ninety-nine patients, aged 70 years and over (mean age+/-SD, 82+/-6, 74% women), were randomly assigned to postoperative care in a specialized geriatric ward or a conventional orthopedic ward. The intervention consisted of staff education focusing on the assessment, prevention and treatment of delirium and associated complications. The staff worked as a team, applying comprehensive geriatric assessment, management and rehabilitation. Patients were assessed using the Mini Mental State Examination and the Organic Brain Syndrome Scale, and delirium was diagnosed according to DSM-IV criteria. RESULTS: The number of days of postoperative delirium among intervention patients was fewer (5.0+/-7.1 days vs 10.2+/-13.3 days, p=0.009) compared with controls. A lower proportion of intervention patients were delirious postoperatively than controls (56/102, 54.9% vs 73/97, 75.3%, p=0.003). Eighteen percent in the intervention ward and 52% of controls were delirious after the seventh postoperative day (p<0.001). Intervention patients suffered from fewer complications, such as decubitus ulcers, urinary tract infections, nutritional complications, sleeping problems and falls, than controls. Total postoperative hospitalization was shorter in the intervention ward (28.0+/-17.9 days vs 38.0+/-40.6 days, p=0.028). CONCLUSIONS: Patients with postoperative delirium can be successfully treated, resulting in fewer days of delirium, fewer other complications, and shorter length of hospitalization.     

Delirium severity and psychomotor types: their relationship with outcomes after hip fracture repair

OBJECTIVES: To validate the Memorial Delirium Assessment Scale (MDAS) as a measure of delirium severity in a cohort of patients aged 65 and older; to examine the association between severity of delirium and patient outcomes; and to examine the association between psychomotor variants of delirium and each of those outcomes. DESIGN: Prospective assessment of sample. SETTING: Hospital. PARTICIPANTS: One hundred twenty-two older patients (mean age +/- standard deviation = 79 +/- 8) who had undergone acute hip fracture surgery. MEASUREMENTS: We used standardized instruments to assess prefracture activities of daily living (ADLs), ambulatory status, cognition, and living situation. Postoperatively, each patient was interviewed daily. Delirium was diagnosed using the Confusion Assessment Method (CAM), and delirium severity was measured using the MDAS. The MDAS was also used to categorize the psychomotor types of delirium into "purely hypoactive" or "any hyperactivity." Telephone or face-to-face interviews were conducted at 1 and 6 months to assess survival, ADL function, ambulatory status, and living situation. RESULTS: Of 122 patients, 40% developed CAM-defined delirium. Delirious patients had higher average MDAS scores than nondelirious patients (11.7 vs 2.4, P <.0001). We used the median of the average MDAS score to classify patients into mild or severe delirium. Severe delirium was generally associated with worse outcomes than was mild delirium, and the associations reached statistical significance for nursing home placement or death at 6 months (52% vs 17%, P =.009). Additionally, patients who did not meet full CAM criteria for delirium experienced worse outcomes if they had some symptoms of delirium than if they had no or few symptoms (nursing home placement or death at 6 months: 27% vs 0%, P =.001). Surprisingly, these patients with subsyndromal delirium who did not fulfill CAM criteria for delirium but demonstrated significant delirium symptoms, had outcomes similar to or worse than those with mild CAM-defined delirium. Pure hypoactive delirium accounted for 71% (34/48) of cases and was less severe than was delirium with any hyperactivity (average MDAS score 10.6 vs 14.8, P =.007). In our cohort, patients with pure hypoactive delirium had better outcomes than did those with any hyperactivity (nursing home placement or death at 1 month: 32% vs 79%, P =.003); this difference persisted after adjusting for severity. CONCLUSION: In this study of delirium in older hip fracture patients, the MDAS, a continuous severity measure, was a useful adjunct to the CAM, a dichotomous diagnostic measure. In patients with CAM-defined delirium, severe delirium was generally associated with worse outcomes than was mild delirium. In patients who did not fulfill CAM criteria, subsyndromal delirium was associated with worse outcomes than having few or no symptoms of delirium. Patients with subsyndromal delirium had outcomes similar to patients with mild delirium, suggesting that a dichotomous approach to diagnosis and management may be inappropriate. Pure hypoactive delirium was more common than delirium with any hyperactive features, tended to be milder, and was associated with better outcomes even after adjusting for severity. Future studies should confirm our preliminary associations and examine whether treatment to reduce the severity of delirium symptoms can improve outcomes after hip fracture repair.     

Delirium in long-term care setting: Indicator to severe morbidity

We aimed to investigate the incidence and characterize predictors associated with delirium in elderly demented and functionally dependent LTC patients. Data collection included: demographic, clinical, functional, nutritional and cognitive data as well as blood counts and chemistry analysis. The tools used to detect delirium were the Confusion Assessment Method (CAM) and the Delirium Rating Scale (DRS), supported by clinical observation. The occurrence of delirium was 34%. The predominant primary etiologies for delirium were infections (58%), following by metabolic abnormalities (36%), and adverse drug effects (18%). The mean duration of delirium was 15.74 days (2-96 days). Independent predictors influencing duration of delirium were low plasma albumin level, high number of comorbid diseases, male gender, advanced age and presence of CVD. Complete resolution of the delirium was found in 33% (30/92), with persistence in 12% (11/92), and no change in 8% (7/92) of the patients. Forty-eight percent (44/92) of the patients died. Most deaths (50%) were in the first month. The main cause of death was infection related (70%), of which bronchopneumonia was predominant (39%), followed by sepsis (32%). Independent predictors of death were infection, advanced age, low plasma albumin level, dehydration and CHF. The early recognition, identification, correction and treatment of underlying conditions especially in very demented, uncooperative and functionally dependent patients may influence their outcome. Any changes in cognitive and functional status are critical in monitoring LTC patients.     

Risk factors and prediction of postoperative delirium in elderly hip-surgery patients: implementation and validation of a medical risk factor model

OBJECTIVES: To evaluate risk factors for postoperative delirium in a cohort of elderly hip-surgery patients and to validate a medical risk stratification model. DESIGN: Prospective cohort study. SETTING: Medical school-affiliated general hospital in Alkmaar, the Netherlands. PARTICIPANTS: Six hundred three hip-surgery patients aged 70 and older screened for risk factors for postoperative delirium. MEASUREMENTS: Predefined risk factors for delirium were assessed on admission. One point was assigned for each of four risk factors present, resulting in three groups: low, intermediate, and high risk. Baseline screening and assessment included the Mini-Mental State Examination, the standardized Snellen test for visual impairment, chart review to determine Acute Physiological and Chronic Health Evaluation II score, and blood urea nitrogen to creatinine ratio. The primary outcome was postoperative delirium, as defined using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and Confusion Assessment Method criteria. All patients were screened daily for delirium. RESULTS: Incidence of delirium was 3.8% in the low-risk group (P<.001), 11.1% in the intermediate-risk group (P=.27, relative risk (RR)=3.0), and 37.1% in the high-risk group (P<.001, RR=9.8). Cognitive impairment at admission had the highest predictive value for postoperative delirium (coefficient of determination=0.15). Contrary to previous findings, age was an independent predictive factor for delirium. Moreover, postoperative delirium was four times as frequent in acute patients as in elective hip-replacement patients. CONCLUSION: The medical risk factor model is valid for elderly hip-surgery patients. Cognitive impairment, age, and type of admission are important risk factors for delirium in this surgical population.