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Clinical Investigations in Critical Care |

Underrecognition of Preexisting Cognitive Impairment by Physicians in Older ICU Patients* FREE TO VIEW

Margaret A. Pisani; Carrie Redlich; Lynn McNicoll; E. Wesley Ely; Sharon K. Inouye
Author and Funding Information

*From the Department of Internal Medicine (Drs. Pisani, Redlich, and Inouye), Yale University School of Medicine, New Haven, CT; Rhode Island Hospital (Dr. McNicoll), Division of Geriatrics, Brown University School of Medicine, Providence, RI; and the Department of Internal Medicine (Dr. Ely), Center for Health Services Research, Vanderbilt University and Veterans Affairs Tennessee Valley Geriatric Research and Education Clinical Center, Nashville, TN.

Correspondence to: Margaret A. Pisani, MD, MPH, FCCP, Yale University School of Medicine, 333 Cedar St, PO Box 208057, New Haven, CT 06520-8057; e-mail: Margaret.Pisani@yale.edu



Chest. 2003;124(6):2267-2274. doi:10.1378/chest.124.6.2267
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Objectives: Cognitive impairment increases with age, as do many serious illnesses requiring intensive care. Little is known, however, about physician recognition of preexisting cognitive impairment in the ICU and which patient factors may play a role in physician recognition.

Design: Cross-sectional comparative study.

Setting: Urban university teaching hospital.

Participants: A total of 165 patients aged ≥ 65 years who were admitted to the medical ICU.

Measurements: Two previously validated proxy measures of cognitive impairment, the modified Blessed dementia rating scale and the informant questionnaire on cognitive decline in the elderly. Physician interviews and medical record abstraction were used to evaluate the recognition of cognitive impairment.

Results: The prevalence of preexisting cognitive impairment in the ICU was 37%. Attending physicians were unaware of the preexisting cognitive impairment in 53% of cases, and intern physicians were unaware in 59% of cases. The recognition of preexisting cognitive impairment increased as the severity of the cognitive impairment increased. Two independent risk factors were identified that were significantly associated with the increased recognition of preexisting cognitive impairment (ie, impairment in activities of daily living or being admitted to the ICU from a nursing home). If both were present, preexisting cognitive impairment was 13 times more likely to be recognized.

Conclusions: A substantial number of older ICU patients have preexisting cognitive impairment on admission to the ICU, and ICU physicians caring for these patients are unaware of this cognitive impairment in the majority of cases. Future research is needed to identify outcomes related to preexisting cognitive impairment and to improve its recognition.

People who are > 65 years of age are the fastest growing segment of the US population, and it is projected that their numbers will increase to 58.9 million by the year 2025.1 Patients in this age group currently account for 42 to 52% of ICU admissions,23 and for more than half of all ICU days.4 The application of critical care can provide substantial benefit to older persons, but they also may be at increased risk for complications from intensive care interventions due to their increased vulnerability. Older patients are at higher risk for having CNS diseases on hospital admission, such as dementia,58 and patients with preexisting cognitive impairment are at the highest risk for developing delirium and attendant poor ICU outcomes.9

The prevalence of dementia in community samples of older persons ranges from 10.3 to 18.8%.1011 Longitudinal studies of dementia suggest that life expectancy is increasing in both Alzheimer and multi-infarct dementia patients.12 While currently affecting 2.2 million Americans, population projections indicate that dementia will affect at least 10 million Americans by 2040.13 In a study of all non-ICU medical admissions Fields et al10 found the prevalence of cognitive impairment using the mini-mental states examination to be 19.8% on admission to the hospital. Mild cognitive impairment, representing forms of cognitive impairment that are not yet classified as dementia, has been increasingly recognized as an important clinical entity, occurring in ≤ 17% of the older population.11,14 The term preexisting cognitive impairment is used to refer to either dementia or mild cognitive impairment that is present in chronic form prior to hospital admission. This distinguishes it from delirium or cognitive impairment that may result directly from the illness or hospitalization.

Previous research15 has shown that cognitive impairment is often unrecognized by physicians. Most patients admitted to an acute care hospital do not have prior documentation of their cognitive function.1617 In a study of medical inpatients, in which the prevalence of cognitive impairment was 31%, referring physicians recognized the cognitive impairment in only 13% of cases and junior medical staff recognized it in only 9% of cases.18 ICU physicians traditionally rely on information from referring physicians or medical records to obtain information about a patient’s preexisting cognitive status, sources that are often lacking this important information. Therefore, preexisting cognitive impairment may not be appropriately evaluated, managed, or incorporated into decision making regarding critical care interventions or aggressiveness of care. Our previous work has evaluated methods to screen for preexisting cognitive impairment in older ICU patients19 and has documented a high prevalence of preexisting cognitive impairment in this setting. This previous work was performed on a subset of patients from the current study. The present study will extend our previous work to investigate physician recognition of preexisting cognitive impairment in the ICU.

The specific aims of this present study were as follows: (1) to evaluate physician recognition of preexisting cognitive impairment in an older ICU population; and (2) to determine the baseline risk factors associated with the recognition of preexisting cognitive impairment.

Setting and Patients

The study participants were consecutive patients aged ≥ 65 years who were admitted to the medical ICU at Yale New Haven Hospital from September 1, 2000, to August 1, 2001. Yale New Haven Hospital is an 800-bed urban teaching hospital with a 14-bed medical ICU, serving a large community as well as a referral population. Age-eligible patients were excluded if there was no identifiable proxy to provide information about the patient, if they had been transferred from any another ICU, or if they died before the proxy interview could be obtained. In addition, patients were excluded if they had been transferred from another ICU because the required baseline information might not have been consistently available.

Of the 252 patients screened, 42 patients were ineligible due to the following: absence of an identifiable proxy (26 patients); or transfer from another ICU (16 patients). Of the 210 eligible patients, 183 (87%) were enrolled in the study. The 27 exclusions were due to proxy refusal (1 patient), death before the proxy interview was completed (6 patients), and staff unavailability during holidays (20 patients). The present analysis was further restricted to the 165 patients who had both attending and intern interviews completed. Physician interviews were not completed in 18 patients due to the intern or attending physicians rotating off the ICU team before the interview could be obtained. Demographic factors, including age, gender, and race, did not differ significantly between enrolled patients (165 patients) and nonenrolled patients (87 patients). Informed consent for participation was obtained from the proxy respondents according to procedures approved by the Institutional Review Board of Yale University School of Medicine.

Study Procedures

Since the patients in this study were critically ill, intubated, and poorly responsive, proxy respondents were used as the primary source of information. To assure high-quality information, proxy respondents were screened to assure that they had sufficient contact to answer questions appropriately about the patient’s cognitive function and activities of daily living (ADL) prior to the acute illness. Briefly, the research nurse first identified whether the participant had been admitted to the ICU from home or from a nursing home. If the participant was admitted to the ICU from home, a proxy was identified who had spent a minimum of 4 h per week with the patient, who had known the patient for at least 5 years, and who could assess the patient’s memory and mental abilities. A hierarchy of proxies was developed that assessed the spouse or live-in partner first, then the live-in child, then other persons who met the criteria to participate in the interview. In some cases involving patients from a nursing home, a family member was administered part of the proxy interview, while a nurse was questioned about the current functional abilities of the patient. If there was no identifiable proxy, then the patient was considered to be ineligible. To minimize reporting and recall bias on the part of the proxy, the proxy interview was obtained within 48 h of patient admission to the ICU.

The proxy interview contained the modified Blessed dementia rating scale (MBDRS),20 the informant questionnaire on cognitive decline in the elderly (IQCODE),21 the ADL scale,22 the instrumental ADL scale,23 questions about prior evaluation for memory problems, prior diagnosis of dementia, treatment with drugs for dementia, marital status, educational level, recognized hearing and vision impairments, existence of advanced directives, use of a regular primary care provider, and use of the Visiting Nurse Association (VNA) services prior to hospitalization. The complete proxy interview took between 10 and 15 min to complete. Two experienced geriatric research nurses performed the proxy interviews. These nurses had undergone training, standardization, and interrater reliability assessment prior to the study.

Both the ICU attending physician and intern physician were interviewed within 48 h of patient admission to the ICU regarding their knowledge of preexisting cognitive impairment or dementia. The physician interview consisted of eight questions about the patient’s medical comorbidities at the time of admission to the ICU. The question about cognitive impairment was imbedded among the other comorbidities to minimize the potential to increase recognition and reporting (ie, the Hawthorne effect) that might result by asking only about cognitive impairment. The physician interviews all were conducted by one physician who was blinded to the cognitive status of the patients. Medical records were reviewed to examine for attending or intern physician recognition of preexisting cognitive impairment or dementia, as documented in their admitting notes.

The medical records also were abstracted for the following: admitting diagnoses; the acute physiology and chronic health evaluation (APACHE) II score,24 the Charlson comorbidity index,25 insurance status, use of intubation, length of stay, mortality, code status on ICU admission, and change in code status.

Two separate nurse researchers carried out the proxy interviews and medical record abstractions independently. Specifically, the nurse-medical record abstractor was blinded to the ratings of preexisting cognitive impairment. All data were obtained using standardized instruments.

Study Variables

To evaluate the prevalence of preexisting cognitive impairment in patients who were admitted to the ICU, two previously validated measures of proxy assessment of cognitive impairment were used, the MBDRS20 and the IQCODE,21 which are described further below. Both of these measures were developed specifically for proxy administration. Prior studies using these instruments evaluated their validity against the direct cognitive testing of patients,2627 and we have previously documented their usefulness in medical ICU patients.19 Given the critical illness of our patients and the high risk for delirium, which would make determinations of cognitive status on ICU admission invalid for determining the preillness baseline level, we did not perform cognitive testing directly with the patients. Both the MBDRS and IQCODE were administered with an introductory statement that asked the proxy to report on cognitive status 1 month prior to the onset of the patient’s current acute ICU illness to minimize any impact due to acute illness or delirium immediately prior to hospitalization.

The MBDRS is an 11-item instrument that has been shown to correlate with the pathologic assessment of dementia, to discriminate between demented and nondemented subjects, and to correlate well with objective patient measures of dementia.26,2829 Examples of items assessed with the MBDRS include memory, coping with money, getting lost or losing things, the ability to perform household tasks, dress, toilet and feed themselves. For the present study, the severity of cognitive impairment was rated by the MBDRS. A score of > 2 but < 4 indicated mild cognitive impairment; a score of ≥ 4 but < 6 indicated moderate impairment; and a score of ≥ 6 indicated severe impairment. These cut points were chosen based on prior literature.2931

The IQCODE21 is a 16-item questionnaire that is designed to measure cognitive decline over time, thus providing a longitudinal perspective of cognitive functioning. In previous studies, the IQCODE has been used in face-to-face interviews, and by telephone or mail interviews. The IQCODE has been shown to correlate with direct patient assessment using cognitive tests and has been used to evaluate the presence of dementia in non-critically ill medical inpatients, as well as to predict the development of dementia after hospital discharge.21,3234 Examples of items assessed with the IQCODE include memory, coping with money, ability to learn new things, following a story, and the ability to handle simple arithmetic.2223

The prevalence of cognitive impairment for the present study was determined by applying a reference standard, which consisted of a composite measure incorporating both instruments (ie, MBDRS and IQCODE), as was done in our previous study.19 The composite measure was based on widely used, published cut points, for both instruments, that were chosen to capture mild cases, as well as moderate-to-severe cases, of cognitive impairment. Our previous work19 demonstrated good correlation between the two measures for capturing preexisting cognitive impairment (overall agreement, 86%; κ = 0.69) and documented the usefulness of the composite measure for preexisting cognitive impairment.

Baseline patient-related variables were evaluated as risk factors for the underrecognition of preexisting cognitive impairment by the ICU physicians. The baseline variables examined included patient characteristics such as age, sex, race, marital status, educational level, Medicaid status, ICU admission from a nursing home, VNA services, resuscitation status, outpatient care prior to hospital admission, vision and/or hearing impairment, functional disability (ie, ADL score), severity of illness (ie, APACHE II score), and Charlson comorbidity index. Definitions and cut points for variables were selected a priori based on clinically meaningful thresholds or previously published studies. Any ADL impairment was defined as the need for physical assistance with at least one of seven basic care skills (ie, feeding, bathing, grooming, toileting, transferring, or walking) by proxy report referent to 1 month before hospital admission. This cut point has been used previously.35Hearing impairment was defined as the use of a hearing aid, as determined by proxy report. Vision impairment was defined as being legally blind, as determined by proxy report. An APACHE II score of ≥ 24 was chosen to represent the most critically ill patients. A Charlson comorbidity index score of ≥ 1 was used to indicate any comorbidity. Education level less than high school was examined as a risk factor, and it represented 65% of our study population.

Outcomes

The primary outcome was physician recognition of preexisting cognitive impairment. To best represent physician recognition, a variable was created to capture any recognition based on interview or medical record data. Recognition by medical record was considered to be present if there was documentation in either the attending or intern physician’s ICU admission notes of the terms dementia, cognitive impairment, or organic brain syndrome. Recognition by interview was determined by a “yes” response to the cognitive impairment/dementia question from the physician interview by either the attending physician or the intern physician. The composite measure, combining medical record and interview data from both the attending and intern physicians, was created to incorporate physician recognition at both levels of training and from both sources of information, with the assumption that physicians may have knowledge that may not be documented in the chart.

Statistical Analysis

The prevalence of preexisting cognitive impairment in the sample and rates of physician recognition were determined by univariate analysis. For comparison of physician recognition by interview vs medical record data, the κ coefficient for concordance was used as an index of agreement exceeding chance. κ Values of > 0.75 were considered to indicate excellent agreement beyond chance, values from 0.40 to 0.75 to indicate fair-to-good agreement beyond chance, and values of < 0.40 to indicate poor agreement beyond chance.36 Physician recognition of preexisting cognitive impairment was compared with the reference standard for cognitive impairment using bivariate analyses, and sensitivity and specificity were calculated using standard formulas. Bivariate analyses were used to evaluate risk factors for the underrecognition of preexisting cognitive impairment by physicians, and crude odds ratios and associated 95% confidence intervals were calculated. Variables with p values of < 0.10 and clinical relevance were selected for evaluation in multiple logistic regression analysis. The final variables were selected with a backward stepwise algorithm (p value to remove was < 0.10).

All statistical analyses were two-tailed, and p < 0.05 was considered to be statistically significant. All analyses were performed using a statistical software package (SAS, version 8; SAS Institute; Cary, NC).

The baseline characteristics of the study population (n = 165) are presented in Table 1 . Forty-one percent of the ICU admissions were due to primary respiratory causes. The mean APACHE II (± SD) score on ICU admission was 23 ± 6.4, indicating severe illness, and the mean Charlson comorbidity index score25 was 2.16 ± 2.1, indicating at least a moderate degree of comorbidity. Eighty-nine percent of participants had medical care provided by an outpatient primary physician prior to ICU admission.

The prevalence of preexisting cognitive impairment was 63 of 165 patients (38%). Patients with preexisting cognitive impairment were significantly older (75.5 vs 79.0 years, respectively; p = .002), more likely to be women (64% vs 36%, respectively; p = .03), less likely to be currently married (33% vs 67%, respectively; p = .01), more likely to have been admitted to the ICU from a nursing home (33% vs 9%, respectively; p < .0001), and more likely to have higher APACHE II scores on ICU admission (24.5 vs 21.9, respectively; p = .01) than those without preexisting cognitive impairment. There were no significant differences in race, education, number of comorbidities on ICU admission, or code status on ICU admission, or ICU admission due to respiratory or cardiac causes between patients with and without preexisting cognitive impairment. Patients admitted to the ICU for GI bleeding were less likely to have preexisting cognitive impairment (15% vs 30%, respectively; p = .01). Notably, there were no significant differences between the prevalence of preexisting cognitive impairment based on who the proxy respondent was (eg, spouse vs child).

The ICU attending physicians consisted of a group of physicians who were board-certified in pulmonary and critical care medicine and were in an academic practice. They rotate through the ICU in 2-week blocks. This study included all 15 of the ICU attending physicians at Yale New Haven Hospital. The intern physicians consisted of first-year internal medicine residents who spend 1 month rotating through the ICU. This study included 44 of the 60 intern physicians (73%) in the internal medicine residency training program. In the majority of cases, none of these physicians had previously cared for these patients.

Attending physicians documented evidence of preexisting cognitive impairment in the medical record in 15% of patients, and by interview in 16% of patients. Intern physicians documented evidence of preexisting cognitive impairment in the medical record in 14% of cases, and by interview in 21% of cases. There was fair agreement between physician recognition by chart documentation and by interview (attending physicians, κ = 0.69; intern physicians, κ = 0.67). Proxies reported a prior physician diagnosis of cognitive impairment in only 9% of patients.

Table 2 compares physician reporting of preexisting cognitive impairment vs our reference standard for cognitive impairment, determined by proxy interview, as described above. The sensitivity of attending physician recognition of preexisting cognitive impairment was 47%, and the specificity was 93%. The sensitivity of intern physician recognition of preexisting cognitive impairment was 41%, and specificity was 86%. Thus, attending physicians were unaware of 53% of cases of preexisting cognitive impairment, and intern physicians were unaware of 59% of cases. Both attending physician and intern physician recognition of preexisting cognitive impairment significantly increased as the severity of cognitive impairment increased (p = 0.0001 trend) [Table 3 ] .

Potential variables associated with the recognition of preexisting cognitive impairment by ICU physicians are presented in Table 4 . Of the 15 variables considered, 6 were selected for multivariable analyses on the basis of clinical relevance and quantitative significance (p < .10), as follows: age ≥ 80 years; any impairment in ADL; admission from a nursing home; marital status; resuscitation status on ICU admission; and receiving outpatient care prior to ICU admission. After multivariable analysis, two final factors were predictors of physicians correctly recognizing preexisting cognitive impairment (ie, any impairment in ADL and ICU admission from a nursing home) [Table 4] . The physician’s ability to identify patients with preexisting cognitive impairment increased significantly as the number of patient factors present increased (p < 0.001 trend) [Table 5 ] . Patients with both risk factors present were 13-fold more likely to be recognized than those with no risk factors at baseline.

This study of older ICU patients documents the substantial prevalence of preexisting cognitive impairment (38%). The attending ICU physicians caring for these patients recognized this preexisting cognitive impairment in only 47% of patients, and intern physicians in only 41% of patients. We have identified two patient characteristics, impairment in ADL and ICU admission from a nursing home, that significantly influence physician recognition of preexisting cognitive impairment. If both factors are present, physician recognition of preexisting cognitive impairment is increased 13-fold.

These findings confirm and extend the previous literature that shows that physician recognition of cognitive impairment among community physicians is equally poor.16,18,37 In a previous hospital-based study, Roca et al15 found that intern physicians recognized dementia in 79% of cases, but they excluded critically ill patients from their study.

The recognition of cognitive impairment by both attending and intern physicians significantly increased as the severity of cognitive impairment increased. This makes clinical sense, since more severe impairment is more easily detectable. Moreover, it is likely that patients with more severe cognitive impairment were admitted to the ICU from nursing homes or received diagnoses of preexisting cognitive impairment by their primary physicians, further increasing the likelihood of recognition by the ICU physicians. Proxy respondents reported a prior physician diagnosis of cognitive impairment in only 9% of the study participants, suggesting either that community physicians are not recognizing cognitive impairment or that they are not communicating the diagnosis to the families.

The rate of false-positive recognition was 7% for attending physicians and 14% for interns, indicating that ICU physicians sometimes reported preexisting cognitive impairment when it was not present by the reference standard. Possible explanations include that physicians may have mistakenly identified current or previous episodes of delirium, as dementia or chronic cognitive impairment. In addition, physicians may have spoken with different family members or proxies who may have given different information about preexisting cognitive impairment.

We have identified ICU admission from a nursing home and impairment in ADL as two independent baseline risk factors that increase ICU physician recognition of preexisting cognitive impairment. These risk factors are clinically sensible, and patients with both risk factors present are 13 times more likely to be recognized than patients without these factors.

A few limitations deserve comment. First, direct testing of patients for preexisting cognitive and functional status was not feasible in this study. However, we used the best available proxy measures and implemented strict screening of proxy respondents to assure the most accurate data. Furthermore, no studies in medical ICUs will have the luxury of baseline neuropsychological testing due to the emergent nature of the ICU admissions. Another issue in our design regards the frequent interviews of the physicians to determine their recognition of cognitive impairment. These interviews may have heightened physician awareness of the issue. Despite this potential Hawthorne effect, however, the rates of recognition remained relatively low and did not change over time. We did not assess where physicians obtained their information on preexisting cognitive impairment, since we wanted to avoid further highlighting awareness of this area. However, the source of information (eg, community physician, family members, or medical records) will be important to investigate in future studies. Finally, this study was based on a single academic medical center, and the results may not be generalizable to other settings.

Information concerning preexisting cognitive status is important for appropriate clinical decision making for several reasons. Knowledge of a patient’s preexisting cognitive status provides critical information that can impact on health care at many levels, including decision-making capacity, informed consent, and evaluation of mental status changes that frequently occur during ICU stays. Cognitive impairment is particularly relevant to the choice of psychoactive medications, which can have an impact on subsequent cognitive functioning. The recognition of preexisting cognitive impairment may play an important role in appropriately involving surrogate decision-makers, thus assuring appropriately informed decision making regarding the use of ICU interventions, changes in code status, and disposition on discharge from the ICU.

Future studies are needed to determine the impact of preexisting cognitive impairment on functional and cognitive outcomes in older ICU patients. Examination of the interactions between preexisting cognitive impairment and processes of care in the ICU, including the use of medications such as sedatives and narcotics, needs to be studied further. The recognition of preexisting cognitive impairment and its impact on decision making in the ICU will play an important role in the care of our aging population.

Abbreviations: ADL = activities of daily living; APACHE = acute physiology and chronic health evaluation; IQCODE = informant questionnaire on cognitive decline in the elderly; MBDRS = modified Blessed dementia rating scale; VNA = Visiting Nurse Association

This work was supported in part by grants from the American Lung Association and Connecticut Thoracic Society (ID No. CG-002-N) and the National Institute on Aging (RO1AG12551), and by in-kind support from the Claude D. Pepper Older Americans Independence Center (grant No. P60AG10469). Dr. Pisani is a recipient of the John A. Hartford Foundation, Association of Subspecialty Professors, and the CHEST Foundation of the American College of Chest Physicians Geriatric Development Research Award and a Merck/AFAR Junior Investigator Award. Part of this work was completed while Dr. Pisani was a Hartford Center of Excellence in Aging at Yale Scholar (grant No. 97266). Dr. Inouye is a recipient of a Midcareer Award from the National Institute on Aging (K24AG00949) and a Donaghue Investigator Award from the Patrick and Catherine Weldon Donaghue Medical Research Foundation (DF98–105). Dr. Ely is a Geriatric Research and Education Clinical Center (GRECC) investigator. Dr. Redlich is a recipient of a National Institutes of Health Midcareer Award (K24ES00355).

Table Graphic Jump Location
Table 1. Baseline Characteristics of Total Study Population (n = 165)*
* 

Values given as mean ± SD (range) or No. (%). IADL = instrumental ADL score.

 

The majority of hospital admissions for cardiac problems were to a separate coronary care unit.

 

Includes patients with overdoses, infections without sepsis, renal failure, and electrolyte abnormalities.

Table Graphic Jump Location
Table 2. Reporting of Preexisting Cognitive Impairment*
* 

n = 165; CI = cognitive impairment.

Table Graphic Jump Location
Table 3. Physician Recognition by Level of Cognitive Impairment*
* 

Levels of cognitive impairment were determined using the MBDRS, as follows: mild CI, MBDRS > 2 but < 4; moderate CI, MBDRS ≥ 4 but < 6; and severe CI, MBDRS ≥ 6. See Table 2 for abbreviation not used in the text.

Table Graphic Jump Location
Table 4. ICU Physicians’ Reporting of Cognitive Impairment Based on Patient Characteristics*
* 

Values given as No. (%) or relative risk (95% confidence interval).

 

Final variables selected by with a backwards-stepwise algorithm (p < 0.10 to remove).

 

p < 0.05.

Table Graphic Jump Location
Table 5. Patient Characteristics Associated With Recognition of Preexisting Cognitive Impairment by ICU Physicians by Number of Risk Factors*
* 

n/N = No. of patients in whom cognitive impairment was recognized by physicians/total No. of patients with risk factor. There was a general trend in comparisons of p < 0.001 (by Mantel-Haenszel χ2).

The authors acknowledge the contributions of Peter Charpentier for database development, David Bruce for data management, Ling Han for statistical support, Wanda Carr for data entry, and Sandy Ginter and Karen Wu for enrolling participants and interviewing family members. We thank the families, nurses, and physicians in the Yale Medical Intensive Care Unit, whose cooperation and participation made this study possible.

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Feinstein, A. Clinical epidemiology: the architecture of clinical research. 1985; WB Saunders. Philadelphia, PA:.
 
McCartney, JR, Palmateer, LM Assessment of cognitive deficit in geriatric patients: a study of physician behavior.J Am Geriatr Soc1985;33,467-471. [PubMed]
 

Figures

Tables

Table Graphic Jump Location
Table 1. Baseline Characteristics of Total Study Population (n = 165)*
* 

Values given as mean ± SD (range) or No. (%). IADL = instrumental ADL score.

 

The majority of hospital admissions for cardiac problems were to a separate coronary care unit.

 

Includes patients with overdoses, infections without sepsis, renal failure, and electrolyte abnormalities.

Table Graphic Jump Location
Table 2. Reporting of Preexisting Cognitive Impairment*
* 

n = 165; CI = cognitive impairment.

Table Graphic Jump Location
Table 3. Physician Recognition by Level of Cognitive Impairment*
* 

Levels of cognitive impairment were determined using the MBDRS, as follows: mild CI, MBDRS > 2 but < 4; moderate CI, MBDRS ≥ 4 but < 6; and severe CI, MBDRS ≥ 6. See Table 2 for abbreviation not used in the text.

Table Graphic Jump Location
Table 4. ICU Physicians’ Reporting of Cognitive Impairment Based on Patient Characteristics*
* 

Values given as No. (%) or relative risk (95% confidence interval).

 

Final variables selected by with a backwards-stepwise algorithm (p < 0.10 to remove).

 

p < 0.05.

Table Graphic Jump Location
Table 5. Patient Characteristics Associated With Recognition of Preexisting Cognitive Impairment by ICU Physicians by Number of Risk Factors*
* 

n/N = No. of patients in whom cognitive impairment was recognized by physicians/total No. of patients with risk factor. There was a general trend in comparisons of p < 0.001 (by Mantel-Haenszel χ2).

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