Critical Illness and the Frailty Syndrome: Mechanisms and Potential Therapeutic Targets

Geriatric syndromes, chronic inflammation, and advances in the management of frailty: A review with new insights

As people age, geriatric syndromes characterized by frailty significantly impact both clinical practice and public health. Aging weakens people's immune functions, leading to chronic low-grade inflammation that ultimately contributes to the development of frailty. Effectively managing geriatric syndromes and frailty can help alleviate the economic burden of an aging population. This review delves into the intricate relationship among aging, infection-induced inflammation, chronic inflammation, and frailty. In addition, it analyzes various approaches and interventions to address frailty, such as smart rehabilitation programs and stem-cell treatments, offering promising solutions in this new era. Given the importance of this topic, further research into the mechanisms of frailty is crucial. Equally essential is the devising of relevant measures to delay its onset and the formulation of comprehensive clinical, research, and public health strategies to enhance the quality of life for elderly individuals.

Effect of Frailty on Hospital Outcomes Among Pediatric Cancer Patients in the United States: Results From the National Inpatient Sample

BACKGROUND

Studies on frailty among pediatric patients with cancer are scarce. In this study, we sought to understand the effects of frailty on hospital outcomes in pediatric patients with cancer.

METHODS

This retrospective study used data collected and stored in the Nationwide Inpatient Sample (NIS) between 2005 and 2014. These were hospitalized patients and hence represented the sickest group of patients. Frailty was measured using the frailty definition diagnostic indicator by Johns Hopkins Adjusted Clinical Groups.

RESULTS

Of 187,835 pediatric cancer hospitalizations included in this analysis, 11,497 (6.1%) were frail. The average hospitalization costs were $86,910 among frail and $40,358 for nonfrail patients. In propensity score matching analysis, the odds of in-hospital mortality (odds ratio, 2.08; 95% CI, 1.71-2.52) and length of stay (odds ratio, 3.76; 95% CI, 3.46-4.09) were significantly greater for frail patients. The findings of our study suggest that frailty is a crucial clinical factor to be considered when treating pediatric cancer patients in a hospital setting.

CONCLUSIONS

These findings highlight the need for further research on frailty-based risk stratification and individualized interventions that could improve outcomes in frail pediatric cancer patients. The adaptation and validation of a frailty-defining diagnostic tool in the pediatric population is a high priority in the field.

Changes in Telomere Length and Indicators of Oxidative Stress in Critically Ill Mechanically Ventilated Adults - A Pilot Study

BACKGROUND

Telomeres are structures at the end of chromosomes that shorten with each cell division. The purpose of this pilot project is to report changes in telomere length (T/S ratio), indicators of oxidative stress (serum protein carbonyl, vitamin C, GSH:GSSG, and total antioxidant capacity) from Intensive Care Unit (ICU) admission to ICU discharge, and to explore their association with ICU-related morbidities among critically ill mechanically ventilated adults.

METHODS

Blood was collected from mechanically ventilated patients (n = 25) at enrollment and within 48 hours of ICU discharge. Telomere length from peripheral blood mononuclear cells (PBMCs) was determined using RTqPCR. ELISAs were used to measure indicators of oxidative stress. Descriptive analysis, paired t-tests, and Pearson's correlations were performed.

RESULTS

Mean age was 62.0 ± 12.3 years, 28.6% were male, and 76.2% were White with disease severity using APACHE III (74.6 ± 24.6) and SOFA (7.6 ± 3.2). Mean T/S ratios shortened (ICU: 0.712, post-ICU: 0.683, p < 0.001, n = 19) and serum protein carbonyl increased (ICU: 7437 nmol/mg ± 3328, post-ICU: 10,254 nmol/mg ± 3962, p < 0.005) as did the oxidative stress index (protein carbonyl/GSH:GSSG, ICU: 1049.972 ± 420.923, post-ICU: 1348.971 ± 417.175, p = 0.0104). T/S ratio was positively associated with APACHE III scores (ICU: r = 0.474, post-ICU: r = 0.628, p < 0.05).

CONCLUSIONS

Pilot findings suggest that critical illness significantly correlates with telomere attrition, perhaps due to increased oxidative stress. Future larger and longitudinal studies investigating mechanisms of telomere attrition and associations with clinical outcomes are needed to identify potential modifiable factors for subsequent intervention to improve outcomes for critically ill patients.

Analysis of systolic and diastolic blood pressure variability in frail, pre-frail, and non-frail elderly patients: The relationship between frailty syndrome and blood pressure variability in the elderly

Frailty can change the prognosis and treatment approach of chronic diseases. We, therefore, conducted this study to explore the relationship between frailty syndrome and blood pressure variability in the elderly. The clinical data of 150 elderly patients with debilitating syndrome admitted to the neurology department of our hospital from May 2021 to May 2022 were selected, and they were grouped according to Fried debilitation scale and divided into 50 cases each in the debilitation group, pre-debilitation group, and no-debilitation group. The general data, co-morbidities, medications, and biochemical indexes were collected. The 24-hour ambulatory blood pressure monitoring was performed in each group, and the mean systolic blood pressure, diastolic blood pressure, nocturnal systolic load value, and diastolic load value were analyzed to determine the relationship between blood pressure variability and senile frailty. Serum albumin (ALB) and high-density lipoprotein were significantly lower in the debilitated and pre-debilitated groups than in the non-debilitated group (P < .05). Multivariate logistic regression analysis revealed that age (odds ratio [OR]: 3.910, 95% confidence intervals [CI]: 2.021-5.402) was a risk factor for frailty in the elderly, and serum ALB (OR: 0.656, 95% CI: 0.110-0.960) and HDL (OR: 0.581, 95% CI: 0.237-0.944) were protective factors for frailty in the elderly. Age, type of medication taken, co-morbidities, serum ALB, and HDL are influencing factors of debilitating syndrome. Serum ALB and HDL are protective factors against debilitating syndrome in the elderly. Age is an independent risk factor of debilitation in the elderly and increased fluctuation of blood pressure in the elderly can increase their risk of developing debilitating syndrome.

Elderly Patients and Management in Intensive Care Units (ICU): Clinical Challenges

There is a growing population of older adults requiring admission to the intensive care unit (ICU). This population outpaces the ability of clinicians with geriatric training to assist in their management. Specific training and education for intensivists in the care of older patients is valuable to help understand and inform clinical care, as physiologic changes of aging affect each organ system. This review highlights some of these aging processes and discusses clinical implications in the vulnerable older population. Other considerations when caring for these older patients in the ICU include functional outcomes and morbidity, as opposed to merely a focus on mortality. An overall holistic approach incorporating physiology of aging, applying current evidence, and including the patient and their family in care should be used when caring for older adults in the ICU.

Development and validation of an intensive care unit acquired weakness prediction model: A cohort study

Background

At present, intensive care unit acquired weakness (ICU-AW) has become an important health care issue. The aim of this study was to develop and validate an ICU-AW prediction model for adult patients in intensive care unit (ICU) to provide a practical tool for early clinical diagnosis.

Methods

An observational cohort study was conducted including 400 adult patients admitted from September 2021 to June 2022 at an ICU with four ward at a medical university affiliated hospital in China. The Medical Research Council (MRC) scale was used to assess bedside muscle strength in ICU patients as a diagnostic basis for ICUAW. Patients were divided into the ICU-AW group and the no ICU-AW group and the clinical data of the two groups were statistically analyzed. A risk prediction model was then developed using binary logistic regression. Sensitivity, specificity, and the area under the curve (AUC) were used to evaluate the predictive ability of the model. The Hosmer-Lemeshow test was used to assess the model fit. The bootstrap method was used for internal verification of the model. In addition, the data of 120 patients in the validation group were selected for external validation of the model.

Results

The prediction model contained five risk factors: gender (OR: 4.31, 95% CI: 1.682-11.042), shock (OR: 3.473, 95% CI: 1.191-10.122), mechanical ventilation time (OR: 1.592, 95% CI: 1.317-1.925), length of ICU stay (OR: 1.085, 95% CI: 1.018-1.156) and age (OR: 1.075, 95% CI: 1.036-1.115). The AUC of this model was 0.904 (95% CI: 0.847-0.961), with sensitivity of 87.5%, specificity of 85.8%, and Youden index of 0.733. The AUC of the model after resampling is 0.889. The model verification results showed that the sensitivity, specificity and accuracy were 71.4, 92.9, and 92.9%, respectively.

Conclusion

An accurate, and readily implementable, risk prediction model for ICU-AW has been developed. This model uses readily obtained variables to predict patient ICU-AW risk. This model provides a tool for early clinical screening for ICU-AW.

Oxidative Stress in ICU Patients: ROS as Mortality Long-Term Predictor

Lipid peroxidation, protein oxidation, and mutations in mitochondrial DNA generate reactive oxygen species (ROS) that are involved in cell death and inflammatory response syndrome. ROS can also act as a signal in the intracellular pathways involved in normal cell growth and homeostasis, as well as in response to metabolic adaptations, autophagy, immunity, differentiation and cell aging, the latter of which is an important characteristic in acute and chronic pathologies. Thus, the measurement of ROS levels of critically ill patients, upon admission, enables a prediction not only of the severity of the inflammatory response, but also of its subsequent potential outcome. The aim of this study was to measure the levels of mitochondrial ROS (superoxide anion) in the peripheral blood lymphocytes within 24 h of admission and correlate them with survival at one year after ICU and hospital discharge. We designed an observational prospective study in 51 critical care patients, in which clinical variables and ROS production were identified and correlated with mortality at 12 months post-ICU hospitalization. Oxidative stress levels, measured as DHE fluorescence, show a positive correlation with increased long-term mortality. In ICU patients the major determinant of survival is oxidative stress, which determines inflammation and outlines the cellular response to inflammatory stimuli.

Association of Frailty With the Risk of Mortality and Resource Utilization in Elderly Patients in Intensive Care Units: A Meta-Analysis

Background: The associations of frailty with the risk of mortality and resource utilization in the elderly patients admitted to intensive care unit (ICU) remain unclear. To address these issues, we performed a meta-analysis to determine whether frailty is associated with adverse outcomes and increased resource utilization in elderly patients admitted to the ICU.

Methods: We searched PubMed, EMBASE, ScienceDirect, and Cochrane Central Register of Controlled Trials through August 2021 to identify the relevant studies that investigated frailty in elderly (≥ 65 years old) patients admitted to an ICU and compared outcomes and resource utilization between frail and non-frail patients. The primary outcome was mortality. We also investigated the prevalence of frailty and the impact of frailty on the health resource utilization, such as hospital length of stay (LOS) and resource utilization of ICU.

Results: A total of 13 observational studies enrolling 64,279 participants (28,951 frail and 35,328 non-frail) were finally included. Frailty was associated with an increased risk of short-term mortality (10 studies, relative risk [RR]: 1.70; 95% CI: 1.45–1.98), in-hospital mortality (five studies, RR: 1.73; 95% CI: 1.55–1.93), and long-term mortality (six studies, RR: 1.86; 95% CI: 1.44–2.42). Subgroup analysis showed that retrospective studies identified a stronger correlation between frailty and hospital LOS (three studies, MD 1.14 d; 95% CI: 0.92–1.36).

Conclusions: Frailty is common in the elderly patients admitted to ICU, and is associated with increased mortality and prolonged hospital LOS.

Trial registration: This study was registered in the PROSPERO database (CRD42020207242).