***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Background The purpose of this study was to identify predictors of 3-month mortality in critically ill older persons under medical care and to assess the clinical impact of an ICU stay on physical and cognitive dependence and subjective health status in survivors . Methods We conducted a prospect i ve observational cohort study including all older persons 75 years and older consecutively admitted into ICU during a one-year period , except those admitted after cardiac arrest , All patients were followed for 3 months or until death . Comorbidities were assessed using the Charlson index and physical dependence was evaluated using the  Katz index of Activity of Daily Living ( ADL ) .  Cognitive dependence was determined by a score based on the individual components of the Lawton index of Daily Living and subjective health status was evaluated using the Nottingham  Health Profile ( NHP ) score . Results One hundred patients were included in the analysis . The mean age was 79.3 ± 3.4 years .  The median Charlson index was 6 [ IQR , 4 to 7 ] and the mean ADL and cognitive scores were 5.4 ± 1.1 and 1.2 ± 1.4 , respectively , corresponding to a population with a high level of comorbidities but low physical and cognitive dependence . Mortality was 61/100 ( 61 % ) at 3 months . In multivariate analysis only comorbidities assessed by the Charlson index [ Adjusted Odds Ratio , 1.6 ; 95 % CI , 1.2 - 2.2 ; p < 0.003 ] and the number of organ failures assessed by the SOFA score [ Adjusted Odds Ratio , 2.5 ; 95 % CI , 1.1 - 5.2 ; p < 0.02 ] were independently associated with 3-month mortality . All 22 patients needing renal support after Day 3 died . Compared with pre-admission , physical ( p = 0.04 ) , and cognitive ( p = 0.62 ) dependence in survivors had changed very little at 3 months . In addition , the mean NHP score was 213.1 ± 132.8 at 3 months , suggesting an acceptable perception of their quality of life . Conclusions In a selected population of non surgical patients 75 years and older , admission into the ICU is associated with a 3-month survival rate of 38 % with little impact on physical and cognitive dependence and subjective health status . Nevertheless , a high comorbidity level ( ie , Charlson index ) , multi-organ failure , and the need for extra-renal support at the early phase of intensive care could be considered as predictors of death Objective : To examine the impact of delirium during intensive care unit stay on long-term health-related quality of life and cognitive function in intensive care unit survivors . Design : Prospect i ve 18-month follow-up study . Setting : Four intensive care units of a university hospital . Patients : A median of 18 months after intensive care discharge , question naires were sent to 1,292 intensive care survivors with ( n = 272 ) and without ( n = 1020 ) delirium during their intensive care stay . Measurements and Main Results : The  Short Form-36v1 , checklist individual strength-fatigue , and cognitive failure question naire were used . Covariance analysis was performed to adjust for relevant covariates . Of the 915 responders , 171 patients were delirious during their intensive care stay ( median age 65 [ interquartile range 58–85 ] , Acute Physiology and Chronic Health Evaluation II score 17 [ interquartile range 14–20 ] ) , and 745 patients were not ( median age 65 [ interquartile range 57–72 ] , Acute Physiology and Chronic Health Evaluation II score 13 [ interquartile range 10–16 ] ) . After adjusting for covariates , no differences were found between delirium and nondelirium survivors on the Short Form-36 and checklist individual strength-fatigue . However , survivors who had suffered from delirium reported that they made significantly more social blunders , and their total cognitive failure question naire score was significantly higher , compared to survivors who had not been delirious . Survivors of a hypoactive delirium subtype performed significantly better on the domain mental health than mixed and hyperactive delirium patients . Duration of delirium was significantly correlated to problems with memory and names . Conclusions : Intensive care survivors with delirium during their intensive care unit stay had a similar adjusted health-related quality of life evaluation , but significantly more cognitive problems than those who did not suffer from delirium , even after adjusting for relevant covariates . In addition , the duration of delirium was related to long-term cognitive problems BACKGROUND Infectious , autoimmune , and neurodegenerative diseases are associated with profound psychological disturbances . Studies in animals clearly demonstrate that cytokines mediate illness-associated behavioral changes . However , the mechanisms underlying the respective psychological alterations in humans have not been established yet . Therefore , we investigated the effects of low-dose endotoxemia , a well-established and safe model of host-defense activation , on emotional , cognitive , immunological , and endocrine parameters . METHODS In a double-blind , crossover study , 20 healthy male volunteers completed psychological question naires and neuropsychological tests 1 , 3 , and 9 hours after intravenous injection of Salmonella abortus equi endotoxin ( 0.8 ng/kg ) or saline in 2 experimental sessions . Blood sample s were collected hourly , and rectal temperature and heart rate were monitored continuously . RESULTS Endotoxin had no effects on physical sickness symptoms , blood pressure , or heart rate . Endotoxin caused a mild increase in rectal temperature ( 0.5 degrees C ) , and increased the circulating levels of tumor necrosis factor alpha ( TNF-alpha ) , soluble TNF receptors , interleukin (IL)-6 , IL-1 receptor antagonist , and cortisol . After endotoxin administration , the subjects showed a transient significant increase in the levels of anxiety ( effect size [ ES ] = 0.55 ) and depressed mood ( ES = 0.66 ) . Verbal and nonverbal memory functions were significantly decreased ( ES = 0.55 to 0.64 ) . Significant positive correlations were found between cytokine secretion and endotoxin-induced anxiety ( r = 0.49 to r = 0.60 ) , depressed mood ( r = 0.40 to r = 0.75 ) , and decreases in memory performance ( r = 0.46 to r = 0.68 ) . CONCLUSIONS In humans , a mild stimulation of the primary host defense has negative effects on emotional and memory functions , which are probably caused by cytokine release . Hence , cytokines represent a novel target for neuropsychopharmacological research Objective Recent studies have shown significant cognitive problems some months after critical illness . However there has been no research examining cognitive function within the intensive care unit ( ICU ) in non-delirious patients . Design and setting A prospect i ve study in an ICU . Patients and participants Using the  Cambridge Neuropsychological Test Automated Battery ( CANTAB ) , 30 long-stay , tracheal-intubated ICU patients were tested . Prior to testing on ICU the  Confusion Assessment Measure ( CAM-ICU ) was administered and only those patients clearly not delirious and off sedation for several days were tested . The CANTAB tests were repeated a week after ICU discharge on the general ward and then again at 2 months . Sixteen patients completed the follow-up . Results While on ICU all 30 patients showed significant problems with strategic thinking and problem solving ; 20 patients had some problems with memory . The degree of difficulty with problem solving on ICU was correlated with length of ICU stay ( p = 0.011 ) , age ( p = 0.036 ) and length of hospital stay post ICU ( p = 0.044 ) . Problems with memory in ICU and on the general ward were correlated with admission APACHE II score ( p = 0.004 and p = 0.005 respectively ) . At the 2-month follow-up 5 of 16 patients ( 31 % ) scored below the 25 percentile for memory and 8 of 16 ( 50 % ) below the 25 percentile for problem solving ( Slater TA , Jones C , Griffiths RD , Wilson S , Benjamin K ( 2004 ) Cognitive impairment during and after intensive care : a pilot study . Intensive Care Med 30 [ Suppl 1]:S199 ) . Conclusions Difficulties with problem solving and poor memory remained a significant issue for 2 months after ICU discharge Objective To examine neuropsychological function , depression , and quality of life 6 months after discharge in patients who received mechanical ventilation in the intensive care unit . Design Prospect i ve cohort study . Setting Tertiary care , medical and coronary intensive care unit of a university-based medical center . Study Population A total of 275 consecutive , mechanically ventilated patients from a medical intensive care unit were prospect ively followed . At 6 months , 157 were alive , of whom 41 ( 26 % ) returned for extensive follow-up testing . Measurement and Main Results  Neuropsychological testing and assessment of depression and quality of life were performed at 6-month follow-up . Seven of 41 patients were excluded from further analysis due to preexisting cognitive impairment determined via surrogate interviews using the Modified Blessed Dementia Rating Scale and a review of medical records . On the basis of strict criteria derived from normative data , we found that 11 of 34 patients ( 32 % ) were neuropsychologically impaired . Impairment was generally diffuse but occurred primarily in areas of psychomotor speed , visual and working memory , verbal fluency , and visuo-construction . The rate of neuropsychological deficits in the study population was markedly higher than population norms for mild dementia . Scores on the Geriatric Depression Scale – Short Form were significantly more abnormal in the neuropsychologically impaired group than in the nonimpaired group at hospital discharge ( p = .04 ) and at 6-month follow-up ( p = .02 ) , and clinical ly significant depression was found in 27 % of impaired subjects at hospital discharge and in 36 % at 6-month follow-up . No differences were observed between groups in quality of life as measured with the Short Form Health Survey-12 at discharge or 6-month follow-up . Conclusions Prolonged neuropsychological impairment is common among survivors of the medical intensive care unit and occurs with greater than anticipated frequency when compared with relevant normative data . Future investigations are warranted to eluci date the nature of the association between critical illness , neuropsychological impairment , depression , and decreased quality of life Introduction Long-term outcomes of elderly patients after medical ICU care are little known . The aim of the study was to evaluate functional status and quality of life of elderly patients 12 months after discharge from a medical ICU . Methods We prospect ively studied 112/230 healthy elderly patients ( ≥65 years surviving at least 12 months after ICU discharge ) with full functional autonomy without cognitive impairment prior to ICU entry . The main diagnoses at admission using the Acute Physiology and Chronic Health Evaluation III ( APACHE III ) classification diagnosis and length of ICU stay and ICU scores ( APACHE II , Sepsis-related Organ Failure Assessment ( SOFA ) and OMEGA ) at admission and discharge were collected . Comprehensive geriatric assessment included the presence of the main geriatric syndromes and the application of Lawton , Barthel , and Charlson Indexes and Informant Question naire on Cognitive Decline to evaluate functionality , comorbidity and cognitive status , respectively . The  EuroQol-5D assessed quality of life  . Data were collected at baseline , during ICU and ward stay and 3 , 6 and 12 months after hospital discharge . Paired or unpaired T-tests compared differences between groups ( continuous variables ) , whereas the chi-square and Fisher exact tests were used for comparing dichotomous variables . For variables significant ( P ≤ 0.1 ) on univariate analysis , a forward multiple regression analysis was performed . Results Only 48.9 % of patients ( mean age : 73.4 ± 5.5 years ) were alive 12 months after discharge showing a significant decrease in functional autonomy ( Lawton and Barthel Indexes ) and quality of life ( EuroQol-5D ) compared to baseline status ( P < 0.001 , all ) . Multivariate analysis showed a higher Barthel Index and EQ-5D vas at hospital discharge to be associated factors of full functional recovery ( P < 0.01 , both ) . Thus , in patients with a Barthel Index ≥ 60 or EQ-5D vas ≥40 at discharge the hazard ratio for full functional recovery was 4.04 ( 95 % CI : 1.58 to 10.33 ; P = 0.005 ) and 6.1 ( 95 % CI : 1.9 to 19.9 ; P < 0.01 ) , respectively . Geriatric syndromes increased after ICU stay and remained significantly increased during follow-up ( P < 0.001 ) . Conclusions The survival rate of elderly medical patients 12 months after discharge from the ICU is low ( 49 % ) , although functional status and quality of life remained similar to baseline in most of the survivors . However , there was a two-fold increase in the prevalence of geriatric syndromes Objective : To test the hypothesis that duration of delirium in the intensive care unit is an independent predictor of long-term cognitive impairment  after critical illness requiring mechanical ventilation . Design : Prospect i ve cohort study . Setting : Medical intensive care unit in a large community hospital in the United States . 
    Output:
    
Conclusion The results of most studies of the studies review ed suggest that critical illness and ICU treatment are associated with long-term cognitive impairment .