C-reactive protein levels and post-ICU mortality in nonsurgical intensive care patients

Effects of C-reactive protein trajectories of critically ill patients with sepsis on in-hospital mortality rate

Sepsis, a life-threatening condition caused by an inflammatory response to systemic infection, results in a significant social burden and healthcare costs. This study aimed to investigate the relationship between the C-reactive protein (CRP) trajectories of patients with sepsis in the intensive care unit (ICU) and the in-hospital mortality rate. We reviewed 1464 patients with sepsis treated in the ICU of Dongyang People's Hospital from 2010 to 2020 and used latent growth mixture modeling to divide the patients into four classes according to CRP trajectory (intermediate, gradually increasing, persistently high, and persistently low CRP levels). We found that patients with intermediate and persistently high CRP levels had the lowest (18.1%) and highest (32.6%) in-hospital mortality rates, respectively. Multiple logistic regression analysis showed that patients with persistently high (odds ratio [OR] = 2.19, 95% confidence interval [CI] = 1.55-3.11) and persistently low (OR = 1.41, 95% CI = 1.03-1.94) CRP levels had a higher risk of in-hospital mortality than patients with intermediate CRP levels. In conclusion, in-hospital mortality rates among patients with sepsis differ according to the CRP trajectory, with patients with intermediate CRP levels having the lowest mortality rate. Further research on the underlying mechanisms is warranted.

Current Status of Antibiotic Stewardship and the Role of Biomarkers in Antibiotic Stewardship Programs

The importance of antibiotic stewardship is increasingly emphasized in accordance with the increasing incidences of multidrug-resistant organisms and accompanying increases in disease burden. This review describes the obstacles in operating an antibiotic stewardship program (ASP), and whether the use of biomarkers within currently available resources can help. Surveys conducted around the world have shown that major obstacles to ASPs are shortages of time and personnel, lack of appropriate compensation for ASP operation, and lack of guidelines or appropriate manuals. Sufficient investment, such as the provision of full-time equivalent ASP practitioners, and adoption of computerized clinical decision systems are useful measures to improve ASP within an institution. However, these methods are not easy in terms of both time commitments and cost. Some biomarkers, such as C-reactive protein, procalcitonin, and presepsin are promising tools in ASP due to their utility in diagnosis and forecasting the prognosis of sepsis. Recent studies have demonstrated the usefulness of algorithmic approaches based on procalcitonin level to determine the initiation or discontinuation of antibiotics, which would be helpful in decreasing antibiotics use, resulting in more appropriate antibiotics use.

Derivation and validation of a new nutritional index for predicting 90 days mortality after ICU admission in a Korean population

BACKGROUND/PURPOSE

Predicting the mortality in patients admitted to the ICU is important for determining a treatment strategy and public health policy. Although many scores have been developed to predict the mortality, these scores were based on Caucasian population. We aimed to develop a new prognostic index, the New nutritional index (NNI), to predict 90-days mortality after ICU admission based on Korean population.

METHODS

Patients (1453) who admitted intensive care unit (ICU) of the Gangnam Severance hospital were analyzed. After exclusion, 984 patients were randomly divided into internal (n = 702) and external validation (n = 282) data set. The new nutritional index (NNI) was developed using univariate and multivariate logistic regression with backward selection of predictors. Receiver operating characteristic (ROC) curve analysis and comparison of the area under the curve (AUC) verified the better predictor of 90 days-mortality after ICU admission.

RESULTS

The NNI better predicted 90 days-mortality compared to modified NUTRIC score, APACHE II scores, SOFA scores, CRP, glucose, total protein, and albumin level in internal and external data sets, with AUC of 0.862 (SE: 0.017, 95% CI: 0.829-0.895) and 0.858 (SE: 0.015, 95% CI: 0.829-0.887), respectively. The calibration plots using external data set for validation showed a close approximation to the logistic calibration of each nomogram, and p-value of Hosmer and Lemeshow test was 0.1804.

CONCLUSION

The NNI has advantages as a predictor of 90 days mortality based on nutritional status in the Korean population.

High CRP Levels After Critical Illness are Associated With an Increased Risk of Rehospitalization

PURPOSE

Chronic inflammation, even at subclinical levels, is associated with adverse long-term outcome.

PATIENTS AND METHODS

In this prospective, observational study, 66 critically ill patients surviving to hospital discharge were included. C-reactive protein (CRP) levels were determined at hospital discharge, 1, 2, and 6 weeks after hospital discharge. All the patients were repeatedly screened for adverse events resulting in rehospitalization or death for 1.5 years.

RESULTS

After hospital discharge, over two-thirds of the patients exhibited elevated CRP levels (>2.0 mg/L). During the first week, CRP decreased compared with hospital discharge (P < 0.001) but did not change after week 1 (P = 0.67). Age (P = 0.24), surgical status (P = 0.95), or sepsis (P = 0.77) did not influence the CRP course. The latter differed between patients with (n = 15) and without (n = 51) adverse events (P = 0.003). CRP levels of patients without adverse events persistently decreased after hospital discharge (P = 0.03), whereas those of patients with adverse events did not (P = 0.86) but rebounded early.

CONCLUSIONS

Plasma CRP levels in critically ill patients decreased during the first week after hospital discharge but remained unchanged during the subsequent 5 weeks. Over two-thirds of the patients exhibited elevated CRP levels compatible with chronic sub-clinical inflammation. Persistently elevated CRP levels after hospital discharge are associated with higher risk of rehospitalization.

Dose of Early Therapeutic Mobility: Does Frequency or Intensity Matter?

OBJECTIVE

Investigate the feasibility of a nurse-led mobility protocol and compare the effects of once- versus twice-daily episodes of early therapeutic mobility (ETM) and low- versus moderate-intensity ETM on serum biomarkers of inflammation and selected outcomes in critically ill adults.

DESIGN

Randomized interventional study with repeated measures and blinded assessment of outcomes.

SETTING

Four adult intensive care units (ICUs) in two academic medical centers.

SUBJECTS

Fifty-four patients with > 48 hr of mechanical ventilation (MV).

INTERVENTION

Patients were assigned to once- or twice-daily ETM via sealed envelope randomization at enrollment. Intensity of (in-bed vs. out-of-bed) ETM was administered according to protocolized patient assessment.

MEASUREMENTS

Interleukins 6, 10, 8, 15, and tumor necrosis factor-α were collected from serum before and after ETM; change scores were used in the analyses. Manual muscle and handgrip strength, delirium onset, duration of MV, and ICU length of stay (LOS) were evaluated as patient outcomes.

MAIN RESULTS

Hypotheses regarding the inflammatory biomarkers were not supported based on confidence intervals. Twice-daily intervention was associated with reduced ICU LOS. Moderate-intensity (out-of-bed) ETM was associated with greater manual muscle test scores and handgrip strength and reduced occurrence of delirium.

CONCLUSION

Findings from this study suggest that nurses can provide twice-daily mobility interventions that include sitting on the edge of the bed once patients have a stable status without altering a pro-inflammatory serum biomarker profile.

The Association between Red Blood Cell Distribution Width and Mortality in Critically Ill Patients with Acute Kidney Injury

Background

Several investigators have sought risk factors for mortality in acute kidney injury (AKI). However, no epidemiological studies have investigated the impact of red blood cell distribution width (RDW) on prognosis for critically ill patients with AKI. The aim of this study was to investigate the association of RDW with mortality in these patients.

Methods

We analyzed data from the MIMIC-III. RDW was measured upon ICU admission. The association between RDW and mortality of AKI was determined using a multivariate logistic regression and was expressed as the adjusted odds ratio with associated 95% confidence interval (CI). We also conducted subgroup analyses to determine the consistency of this association.

Results

A total of 14,078 critically ill patients with AKI were eligible for this analysis. In multivariate analysis, adjusted for age and gender and compared with the reference group (RDW 11.1-13.4%) related to hospital mortality, the adjusted ORs (95% CIs) for RDW levels 13.5-14.3%, 14.4-15.6%, and 15.7-21.2% were 1.22 (1.05, 1.43), 1.56 (1.35, 1.81), and 2.66 (2.31, 3.06), respectively. After adjusting for confounding factors, with high RDW linked to an increase in mortality (RDW 15.7-21.2% versus 11.1-13.4%: OR, 1.57; 95% CI, 1.22 to 2.01; P trend <0.0001). A similar trend was observed for 30-day mortality.

Conclusions

RDW appeared to be an independent prognostic marker in critically ill patients with AKI and higher RDW was associated with increased risk of mortality in these patients.

Critical care for dengue in adult patients: an overview of current knowledge and future challenges

PURPOSE OF REVIEW

This review aims to update and summarize the current knowledge about clinical features, management, and risk factors of adult dengue patients requiring intensive care with consequently higher risk of mortality.

RECENT FINDINGS

Increasingly, there are more adult dengue patients who require intensive care. This may be due to a shift in epidemiology of dengue infection from mainly a pediatric disease toward adult disease. In addition, multiorgan dysfunction was observed to be a key risk factor for ICU admission and mortality. This may be due to older adults having preexisting comorbidities that potentially predispose to have multiple severe organ impairment. Interventions remain largely supportive but also require more evidence-based trials and treatment protocols.

SUMMARY

These findings highlight the common clinical manifestations of adult dengue patients and the challenges of clinical management in ICU. Risk factors for prediction of adult dengue patients who require ICU are available, but they lack validation and consistent study design for meta-analysis in future. Early recognition of these risk factors, with close monitoring and prompt clinical management, remains critical to reduce mortality.

Biomarkers as predictors of mortality in critically ill patients with solid tumors

Biochemical markers produced by the affected organ or body in response to disease have gained high clinical value due to assess disease development and being excellent predictors of morbidity and mortality. The aim of this study is to analyze different biochemical markers in critically cancer patients and to determine which of them can be used as predictors of mortality. This is a prospective, cross-sectional study conducted at a University Hospital in Porto Alegre - RS. Screening was done to include patients in the study. Serum biochemical markers obtained in the first 24 hours of Intensive Care Unit hospitalization were analyzed. A second review of medical records occurred after three months objected to identify death or Unit discharged. A sample of 130 individuals was obtained (control group n = 65, study group n = 65). In the multivariate model, serum magnesium values ​​OR = 3.97 (1.17; 13.5), presence of neoplasia OR = 2.68 (95% CI 1.13; 6.37) and absence of sepsis OR = 0.31 (95% CI 0.12; 0.79) were robust predictors of mortality. The association of solid tumors, sepsis presence and alteration in serum magnesium levels resulted in an increased chance of mortality in critically ill patients.

One-year survival and resource use after critical illness: impact of organ failure and residual organ dysfunction in a cohort study in Brazil

Introduction

In this study, we evaluated the impacts of organ failure and residual dysfunction on 1-year survival and health care resource use using Intensive Care Unit (ICU) discharge as the starting point.

Methods

We conducted a historical cohort study, including all adult patients discharged alive after at least 72 h of ICU stay in a tertiary teaching hospital in Brazil. The starting point of follow-up was ICU discharge. Organ failure was defined as a value of 3 or 4 in its corresponding component of the Sequential Organ Failure Assessment score, and residual organ dysfunction was defined as a score of 1 or 2. We fit a multivariate flexible Cox model to predict 1-year survival.

Results

We analyzed 690 patients. Mortality at 1 year after discharge was 27 %. Using multivariate modeling, age, chronic obstructive pulmonary disease, cancer, organ dysfunctions and albumin at ICU discharge were the main determinants of 1-year survival. Age and organ failure were non-linearly associated with survival, and the impact of organ failure diminished over time. We conducted a subset analysis with 561 patients (81 %) discharged without organ failure within the previous 24 h of discharge, and the number of residual organs in dysfunction remained strongly associated with reduced 1-year survival. The use of health care resources among hospital survivors was substantial within 1 year: 40 % of the patients were rehospitalized, 52 % visited the emergency department, 90 % were seen at the outpatient clinic, 14 % attended rehabilitation outpatient services, 11 % were followed by the psychological or psychiatric service and 7 % used the day hospital facility. Use of health care resources up to 30 days after hospital discharge was associated with the number of organs in dysfunction at ICU discharge.

Conclusions

Organ failure was an important determinant of 1-year outcome of critically ill survivors. Nevertheless, the impact of organ failure tended to diminish over time. Resource use after critical illness was elevated among ICU survivors, and a targeted action is needed to deliver appropriate care and to reduce the late critical illness burden.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0986-6) contains supplementary material, which is available to authorized users.

Serum procalcitonin level and SOFA score at discharge from the intensive care unit predict post-intensive care unit mortality: a prospective study

Purpose

The final decision for discharge from the intensive care unit (ICU) is uncertain because it is made according to various patient parameters; however, it should be made on an objective evaluation. Previous reports have been inconsistent and unreliable in predicting post-ICU mortality. To identify predictive factors associated with post-ICU mortality, we analyzed physiological and laboratory data at ICU discharge.

Methods

Patients admitted to our ICU between September 2012 and August 2013 and staying for critical care>2 days were included. Sequential Organ Failure Assessment (SOFA) score; systemic inflammatory response syndrome score; white blood cell count; and serum C reactive protein, procalcitonin (PCT), interleukin-6 (IL-6), lactate, albumin, and hemoglobin levels were recorded. The primary end point was 90-day mortality after ICU discharge. Two hundred eighteen patients were enrolled (195 survivors, 23 non-survivors).

Results

Non-survivors presented a higher SOFA score and serum PCT, and IL-6 levels, as well as lower serum albumin and hemoglobin levels. Serum PCT, albumin, and SOFA score were associated with 90-day mortality in multiple logistic regression analysis. Hosmer-Lemeshow test showed chi-square value of 6.96, and P value of 0.54. The area under the curve (95% confidence interval) was 0.830 (0.771–0.890) for PCT, 0.688 (0.566–0.810) for albumin, 0.861 (0.796–0.927) for SOFA score, and increased to 0.913 (0.858–0.969) when these were combined. Serum PCT level at 0.57 ng/mL, serum albumin at 2.5 g/dL and SOFA score at 5.5 predict 90-day mortality, and high PCT, low albumin and high SOFA groups had significantly higher mortality. Serum PCT and SOFA score were significantly associated with survival days after ICU discharge in Cox regression analysis.

Conclusions

Serum PCT level and SOFA score at ICU discharge predict post-ICU mortality and survival days after ICU discharge. The combination of these two and albumin level might enable accurate prediction.

Platelet indices are novel predictors of hospital mortality in intensive care unit patients

BACKGROUND AND OBJECTIVE

Platelet volume indices (PVIs) are inexpensive and readily available in intensive care units (ICUs). However, their association with mortality has never been investigated in a critical care setting. Our study aimed to investigate the association of PVI and mortality in unselected ICU patients.

METHODS

This was a retrospective study conducted in a mixed 24-bed ICU from September 2010 to December 2012. Platelet indices including mean platelet volume (MPV), platelet distribution width (PDW), platelet count, and plateletcrit were measured on ICU entry. Univariable analyses were performed to screen for variables that were associated with mortality. Variables with P < .1 were incorporated into a regression model to adjust for the odds ratio of platelet indices.

RESULTS

A total of 1556 patients were included during the study period, including 1113 survivors and 443 nonsurvivors (mortality rate: 28.47%). Platelet distribution width and MPV were significantly higher in nonsurvivors than in survivors. Platelet distribution width greater than 17% and MPV greater than 11.3 fL were independent risk factors for mortality (adjusted odds ratio: 1.92 and 1.84, respectively) and survival time (hazards ratio: 1.77 and 1.75, respectively).

CONCLUSION

Higher MPV and PDW are associated with increased risk of death, whereas the decrease in plateletcrit is associated with increased mortality risk.

Eosinopenia as a predictor of unexpected re-admission and mortality after intensive care unit discharge

Predicting unexpected intensive care unit (ICU) re-admission and mortality after critical illness is difficult. This study assessed the associations between eosinopenia on the day of ICU discharge and outcomes after critical illness. This retrospective cohort study involved a total of 1446 critically ill patients who survived their first ICU admission between January 2009 and March 2010 in a multidisciplinary ICU in Western Australia. Eosinopenia was defined as eosinophil count <0.01×109/l and the date of censor for survival was 31 October 2011. Of the 1446 patients included in the study, 106 patients (7.3%) were re-admitted to the ICU during the same hospitalisation and 178 patients died (12.3%) after ICU discharge. Eosinopenia at ICU discharge occurred in 130 patients (9.7%) and was more common among those who were subsequently re-admitted (18.6 vs 8.6%) or died after ICU discharge (22.5 vs 7.5%). Eosinopenia remained associated with ICU re-admission (odds ratio 2.50, 95% confidence interval 1.38-4.50; P=0.002) and post-ICU mortality (hazard ratio 2.65, 95% confidence interval 1.77-3.98; P=0.001) after adjusting for age, gender, nocturnal discharge, neutrophil count at ICU discharge, elective surgical admission, Sequential Organ Failure Assessment scores, Acute Physiology and Chronic Health Evaluation II predicted mortality and chronic medical diseases. Eosinopenia at ICU discharge explained about 8.4% of the variability and was the third most important factor in explaining the variability in survival after ICU discharge. In summary, eosinopenia at ICU discharge was associated with an increased risk of unexpected ICU re-admission and post-ICU mortality.

Heart rate before ICU discharge: a simple and readily available predictor of short- and long-term mortality from critical illness

PURPOSE

A heart rate >90 bpm serves as one of four characteristics defining the systemic inflammatory response syndrome and is used in scoring systems to predict in-hospital mortality of intensive care unit (ICU) patients. Despite its central role in critical illness, specific data regarding the relationship between heart rate and outcome are rare.

METHODS

In this post hoc analysis of a prospectively collected database, we analyzed the value of heart rate averaged from four predefined time points during the last 24 h before ICU discharge as a predictor of post-ICU in-hospital and post-hospital mortality in medical ICU patients. Furthermore, the relationship between heart rate and inflammation, as well as the influence of rate control medications on the association between heart rate and outcome were identified.

RESULTS

Among the 702 ICU patients discharged from the ICU, 7.1 % died before hospital discharge. At 4 years of follow-up, post-hospital mortality was 14.4 %. Multivariate Cox proportional hazards models revealed heart rate before ICU discharge (HR 5.95; 95 % CI 1.24-28.63; p = 0.03) as an independent predictor of post-ICU in-hospital mortality. Both heart rate (HR 2.56; 95 % CI, 1.05-6.34; p = 0.04) and the C-reactive protein serum concentration before ICU discharge (HR, 1.26; 95 % CI, 1.09-1.46; p = 0.002) were independently associated with post-hospital mortality. Heart rate control therapy reduced the risk of post-ICU in-hospital (HR 0.38; 95 % CI, 0.18-0.81; p = 0.01) and post-hospital (HR, 0.47; 95 % CI, 0.22-1.00; p = 0.05) mortality.

CONCLUSION

Heart rate evaluated 24 h before ICU discharge was independently associated with post-ICU in-hospital and post-hospital mortality. Pharmacological interventions to control heart rate may beneficially influence post-ICU mortality.

C-reactive protein/albumin ratio predicts 90-day mortality of septic patients

Introduction

Residual inflammation at ICU discharge may have impact upon long-term mortality. However, the significance of ongoing inflammation on mortality after ICU discharge is poorly described. C-reactive protein (CRP) and albumin are measured frequently in the ICU and exhibit opposing patterns during inflammation. Since infection is a potent trigger of inflammation, we hypothesized that CRP levels at discharge would correlate with long-term mortality in septic patients and that the CRP/albumin ratio would be a better marker of prognosis than CRP alone.

Methods

We evaluated 334 patients admitted to the ICU as a result of severe sepsis or septic shock who were discharged alive after a minimum of 72 hours in the ICU. We evaluated the performance of both CRP and CRP/albumin to predict mortality at 90 days after ICU discharge. Two multivariate logistic models were generated based on measurements at discharge: one model included CRP (Model-CRP), and the other included the CRP/albumin ratio (Model-CRP/albumin).

Results

There were 229 (67%) and 111 (33%) patients with severe sepsis and septic shock, respectively. During the 90 days of follow-up, 73 (22%) patients died. CRP/albumin ratios at admission and at discharge were associated with a poor outcome and showed greater accuracy than CRP alone at these time points (p = 0.0455 and p = 0.0438, respectively). CRP levels and the CRP/albumin ratio were independent predictors of mortality at 90 days (Model-CRP: adjusted OR 2.34, 95% CI 1.14–4.83, p = 0.021; Model-CRP/albumin: adjusted OR 2.18, 95% CI 1.10–4.67, p = 0.035). Both models showed similar accuracy (p = 0.2483). However, Model-CRP was not calibrated.

Conclusions

Residual inflammation at ICU discharge assessed using the CRP/albumin ratio is an independent risk factor for mortality at 90 days in septic patients. The use of the CRP/albumin ratio as a long-term marker of prognosis provides more consistent results than standard CRP values alone.

Failure to reduce C-reactive protein levels more than 25% in the last 24 hours before intensive care unit discharge predicts higher in-hospital mortality: a cohort study

PURPOSE

To discharge a patient from the intensive care unit (ICU) is a complex decision-making process because in-hospital mortality after critical illness may be as high as up to 27%. Static C-reactive protein (CRP) values have been previously evaluated as a predictor of post-ICU mortality with conflicting results. Therefore, we evaluated the CRP ratio in the last 24 hours before ICU discharge as a predictor of in-hospital outcomes.

METHODS

A retrospective cohort study was performed in 409 patients from a 6-bed ICU of a university hospital. Data were prospectively collected during a 4-year period. Only patients discharged alive from the ICU with at least 72 hours of ICU length of stay were evaluated.

RESULTS

In-hospital mortality was 18.3% (75/409). Patients with reduction less than 25% in CRP concentrations at 24 hours as compared with 48 hours before ICU discharge had a worse prognosis, with increased mortality (23% vs 11%, P = .002) and post-ICU length of stay (26 [7-43] vs 11 [5-27] days, P = .036). Moreover, among hospital survivors (n = 334), patients with CRP reduction less than 25% were discharged later (hazard ratio, 0.750; 95% confidence interval, 0.602-0.935; P = .011).

CONCLUSIONS

In this large cohort of critically ill patients, failure to reduce CRP values more than 25% in the last 24 hours of ICU stay is a strong predictor of worse in-hospital outcomes.

C-reactive protein as a predictor of mortality in critically ill patients: a meta-analysis and systematic review

C-reactive protein is a marker of inflammatory response and has been widely investigated in cardiovascular and infectious diseases, especially to monitor therapeutic success. However, its role as a predictor of clinical outcome in critically ill patients remains uncertain and controversial. The objective of this study was to investigate the predictive value of C-reactive protein in critically ill patients. The databases of PubMed, the Cochrane clinical trial database and EMBASE (from inception to August 2010) were searched. Prospective non-randomised clinical studies comparing C-reactive protein concentrations between survivors and non-survivors were included. Pooled mean difference in C-reactive protein concentrations between survivors and non-survivors was calculated. Heterogeneity was analysed by I2. Sensitivity and subgroup analyses were conducted to explore the heterogeneity. Fourteen studies containing a total of 1969 patients were finally included in our analysis. The weighted mean difference in the C-reactive protein levels between survivors and non-survivors was 9.15 mg/l (95% confidence interval -6.50 to 24.81). The heterogeneity was large with I2 = 92%. Subsequent investigation of the heterogeneity with sensitivity analyses yielded no significant differences. The subgroup analysis showed that the weighted mean difference in early (within 48 hours) C-reactive protein levels between survivors and non-survivors was not significantly different, in contrast to the late (beyond 48 hours) C-reactive protein level. This was significantly greater in non-survivors with a weighted mean difference of 63.80 mg/l (95% confidence interval 35.67 to 91.93). Our systematic review shows that while the early C-reactive protein concentration is not a good predictor of survival in critically ill patients, the late C-reactive protein concentration may help to identify patients who are at risk of death.

Activated protein synthesis and suppressed protein breakdown signaling in skeletal muscle of critically ill patients

Background

Skeletal muscle mass is controlled by myostatin and Akt-dependent signaling on mammalian target of rapamycin (mTOR), glycogen synthase kinase 3β (GSK3β) and forkhead box O (FoxO) pathways, but it is unknown how these pathways are regulated in critically ill human muscle. To describe factors involved in muscle mass regulation, we investigated the phosphorylation and expression of key factors in these protein synthesis and breakdown signaling pathways in thigh skeletal muscle of critically ill intensive care unit (ICU) patients compared with healthy controls.

Methodology/Principal Findings

ICU patients were systemically inflamed, moderately hyperglycemic, received insulin therapy, and showed a tendency to lower plasma branched chain amino acids compared with controls. Using Western blotting we measured Akt, GSK3β, mTOR, ribosomal protein S6 kinase (S6k), eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1), and muscle ring finger protein 1 (MuRF1); and by RT-PCR we determined mRNA expression of, among others, insulin-like growth factor 1 (IGF-1), FoxO 1, 3 and 4, atrogin1, MuRF1, interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) and myostatin. Unexpectedly, in critically ill ICU patients Akt-mTOR-S6k signaling was substantially higher compared with controls. FoxO1 mRNA was higher in patients, whereas FoxO3, atrogin1 and myostatin mRNAs and MuRF1 protein were lower compared with controls. A moderate correlation (r² = 0.36, p<0.05) between insulin infusion dose and phosphorylated Akt was demonstrated.

Conclusions/Significance

We present for the first time muscle protein turnover signaling in critically ill ICU patients, and we show signaling pathway activity towards a stimulation of muscle protein synthesis and a somewhat inhibited proteolysis.

Usefulness of N-terminal pro-brain natriuretic peptide and C-reactive protein to predict ICU mortality in unselected medical ICU patients: a prospective, observational study

INTRODUCTION

The performance of N-terminal pro-brain natriuretic peptide (NT-proBNP) and C-reactive protein (CRP) to predict clinical outcomes in ICU patients is unimpressive. We aimed to assess the prognostic value of NT-proBNP, CRP or the combination of both in unselected medical ICU patients.

METHODS

A total of 576 consecutive patients were screened for eligibility and followed up during the ICU stay. We collected each patient's baseline characteristics including the Acute Physiology and Chronic Health Evaluation II (APACHE-II) score, NT-proBNP and CRP levels. The primary outcome was ICU mortality. Potential predictors were analyzed for possible association with outcomes. We also evaluated the ability of NT-proBNP and CRP additive to APACHE-II score to predict ICU mortality by calculation of C-index, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) indices.

RESULTS

Multiple regression revealed that CRP, NT-proBNP, APACHE-II score and fasting plasma glucose independently predicted ICU mortality (all P < 0.01). The C-index with respect to prediction of ICU mortality of APACHE II score (0.82 ± 0.02; P < 0.01) was greater than that of NT-proBNP (0.71 ± 0.03; P < 0.01) or CRP (0.65 ± 0.03; P < 0.01) (all P < 0.01). As compared with APACHE-II score (0.82 ± 0.02; P < 0.01), combination of CRP (0.83 ± 0.02; P < 0.01) or NT-proBNP (0.83 ± 0.02; P < 0.01) or both (0.84 ± 0.02; P < 0.01) with APACHE-II score did not significantly increase C-index for predicting ICU mortality (all P > 0.05). However, addition of NT-proBNP to APACHE-II score gave IDI of 6.6% (P = 0.003) and NRI of 16.6% (P = 0.007), addition of CRP to APACHE-II score provided IDI of 5.6% (P = 0.026) and NRI of 12.1% (P = 0.023), and addition of both markers to APACHE-II score yielded IDI of 7.5% (P = 0.002) and NRI of 17.9% (P = 0.002). In the cardiac subgroup (N = 213), NT-proBNP but not CRP independently predicted ICU mortality and addition of NT-proBNP to APACHE-II score obviously increased predictive ability (IDI = 10.2%, P = 0.018; NRI = 18.5%, P = 0.028). In the non-cardiac group (N = 363), CRP rather than NT-proBNP was an independent predictor of ICU mortality.

CONCLUSIONS

In unselected medical ICU patients, NT-proBNP and CRP can serve as independent predictors of ICU mortality and addition of NT-proBNP or CRP or both to APACHE-II score significantly improves the ability to predict ICU mortality. NT-proBNP appears to be useful for predicting ICU outcomes in cardiac patients.