Hip fracture aggravates systemic inflammation and lung injury in aged chronic cigarette smoke exposed rats

Predictive value of the systemic immune-inflammation index on one-year mortality in geriatric hip fractures

BACKGROUND

Geriatric hip fractures are associated with a high incidence of mortality. This study examines the predictive value of the systemic immune-inflammation index (SII) on one-year mortality in elderly hip fracture patients.

METHODS

A single-center retrospective study was conducted between February 2017 and October 2020. Three hundred and eleven surgically treated consecutive hip fracture patients were included in the study. Admission, postoperative first day, and postoperative fifth-day SII values were calculated. The receiver operating characteristic (ROC) curve was used to calculate the cut-off values, and patients were divided into high and low groups according to these cut-off values. After univariate Cox regression analysis, significant factors were included in the multivariate Cox proportional hazards model to adjust the effect of covariates and explore independent predictive factors associated with mortality. Further subgroup analysis was performed to evaluate the accuracy of the results for different clinical and biological characteristics.

RESULTS

The mean age was 80.7 ± 8.0 years, and women made up the majority (67.8%) of the patients. The one-year mortality rate was 28.0%. After univariate and multivariate analyses, high postoperative fifth-day SII remained an independent predictor of one-year mortality (adjusted HR 2.16, 95% CI 1.38-3.38, p = 0.001). Older age, male gender, Charlson comorbidity index (CCI) ≥ 2, and hypoalbuminemia were found to be other independent predictors. The optimal cut-off value of the postoperative fifth-day SII was calculated at 1751.9 units (p < 0.001).

CONCLUSION

The postoperative fifth-day SII is a simple and useful inflammatory biomarker for predicting one-year mortality in patients with hip fracture.

Factors Associated With Hip Fracture Length of Stay Among Older Adults in a Community Hospital Setting

INTRODUCTION

Hip fractures in geriatric populations constitute a heavy burden on the healthcare system. The study goal was to identify patient, hospital, and surgical factors associated with hospital length of stay (LOS) for geriatric patients with hip fractures requiring surgical intervention in a community hospital setting.

METHODS

This was a cross-sectional retrospective chart review of geriatric hip fractures that underwent surgical fixation at a community hospital between 2017 and 2019. The scope of the surgeries was limited to cephalomedullary device fixation or hemiarthroplasty hip fracture surgeries. Sliding hip screw or total hip arthroplasty procedures and patients who died during the index hospitalization were excluded. Median tests were conducted to examine differences between the groups. Unadjusted and adjusted truncated negative binomial regression models were used to examine the factors associated with LOS.

RESULTS

Bivariate analyses revealed results that the factors associated with a longer LOS were preoperative anemia (P = 0.029), blood transfusion (P = 0.022), and the number of days between admission and surgery (P = 0.001). The adjusted regression model results suggested that older patients, patients who underwent surgery more than one day after admission, current smokers, malnourished patients, patients with sepsis, and patients with a history of a thromboembolic event had statistically significant (P < 0.05) longer LOS. However, patients who live in institutions (nursing homes or assisted living) had a shorter LOS than those who live at home alone or with family (P < 0.05).

DISCUSSION

Older adult patients who underwent surgery with a cephalomedullary device or hip hemiarthroplasty for a hip fracture and had preoperative anemia, postoperative blood transfusions, and increased days between admission and surgery had a longer LOS. Additional factors positively associated with a longer LOS included current smokers, malnourishment, admission with sepsis, and patients with a history of a thromboembolic event. Of interest, institutionalized patients had a shorter LOS than those living at home alone or with family.

Postoperative awake prone position in geriatric patients with hip fractures: a protocol for a randomized controlled trial on the efficacy of postoperative prone position in reducing pulmonary complications and improving oxygenation

INTRODUCTION

Postoperative pulmonary complications (PPCs) are prevalent in geriatric patients with hip fractures. Low oxygen level is one of the most important risk factors for PPCs. Prone position has been proven efficacy in improving oxygenation and delaying the progress of pulmonary diseases, especially in patients with acute respiratory distress syndrome induced by multiple etiologies. The application of awake prone position (APP) has also attracted widespread attention in recent years. A randomized controlled trial (RCT) will be carried out to measure the effect of postoperative APP in a population of geriatric patients undergoing hip fracture surgery.

METHODS

This is an RCT. Patients older than 65 years old admitted through the emergency department and diagnosed with an intertrochanteric or femoral neck fracture will be eligible for enrollment and assigned randomly to the control group with routine postoperative management of orthopedics or APP group with an additional prone position for the first three consecutive postoperative days (PODs). Patients receiving conservative treatment will not be eligible for enrollment. We will record the difference in the patient's room-air-breathing arterial partial pressure of oxygen (PaO₂) values between the 4^th POD (POD 4) and emergency visits, the morbidity of PPCs and other postoperative complications, and length of stay. The incidence of PPCs, readmission rates, and mortality rates will be followed up for 90 PODs.

DISCUSSION

We describe the protocol for a single-center RCT that will evaluate the efficacy of postoperative APP treatment in reducing pulmonary complications and improving oxygenation in geriatric patients with hip fractures.

ETHICS AND DISSEMINATION

This protocol was approved by the independent ethics committee (IEC) for Clinical Research of Zhongda Hospital, Affiliated to Southeast University, and is registered on the Chinese Clinical Trial Registry. The findings of the trial will be disseminated through peer-reviewed journals.

ETHICS APPROVAL NUMBER

2021ZDSYLL203-P01 TRIAL REGISTRATION: ChiCTR ChiCTR2100049311 . Registered on 29 July 2021.

TRIAL STATUS

Recruiting. Recruitment is expected to be completed in December 2024.

MicroRNA-205-5p Targets HMGB1 to Suppress Inflammatory Responses during Lung Injury after Hip Fracture

Hip fracture is the most common type of injury in elderly people and is associated with a high incidence of complications and risk of mortality. In these patients, subsequent pulmonary infection can contribute to the development of an acute lung injury, a consequence of the systemic inflammatory response induced by hip fracture. Although the crucial role of microRNAs (miRNAs) in inflammatory responses has been established, the functions of miRNAs in the inflammatory responses associated with lung injury after hip fracture remain poorly understood. In this study, we explored the potential role of miR-205-5p in lung injury after hip fracture in an in vivo hip fracture model and in vitro cultures of human pulmonary alveolar epithelial cells (HPAEpiC). An analysis of clinical serum samples revealed increased levels of miR-205-5p and high mobility group box 1 (HMGB1) after hip fracture. A bioinformatics analysis and dual-luciferase reporter assay identified HMGB1 as a potential target of miR-205-5p. The overexpression of miR-205-5p clearly reduced the expression of HMGB1 and inhibited NF-κB signaling, apoptosis, and proinflammatory cytokine production while enabling continued cell proliferation. Our results demonstrate that the upregulation of miR-205-5p suppresses inflammatory responses and promotes cell viability and proliferation by selectively targeting HMGB1 in the context of lung injury after hip fracture. Therefore, miR-205-5p may be an alternative target of therapeutic strategies for lung injury after hip fracture.

Impact of Cigarette Smoking on Serum Pro- and Anti-Inflammatory Cytokines and Growth Factors

Inflammation plays a key role in the initiation, progression, and clinical manifestation of atherosclerosis. Cigarette smoking is a risk factor for atherosclerosis and cardiovascular disease. The aim of the current study was to investigate the serum concentrations of 12 cytokines and growth factors (EGF, INF-γ, IL-1α/-1β/-2/-4/-6/-8/-10, MCP-1, TNF-α, and VEGF) in an Iranian population, including 192 smokers, comparing these values with concentrations in nonsmokers. One hundred and ninety-two cases were enrolled from the Mashhad University of Medical Sciences. Of these cases, 82 were cigarette smokers and 110 were nonsmokers. Sex and age were matched for the two groups. The serum concentration of 12 cytokines and growth factors were determined using EV-3513-cytokine-biochip arrays, by competitive chemiluminescence immunoassays. The level of serum MCP-1 was significantly ( p < .001) lower in the female group of cigarette smokers (mean = 88.1 dL/ng), compared with nonsmokers (mean = 155.6 dL/ng). There were no significant differences for the other cytokines and growth factors between the groups. Our finding demonstrate the association of MCP-1 with cigarette smoking, supporting further studies in larger population on evaluating the role of cigarette smoking on pro-/anti-inflammatory cytokines.

Plasma mitochondrial DNA levels were independently associated with lung injury in elderly hip fracture patients

INTRODUCTION

Hip fracture in the elderly can induce systemic inflammatory response (SIRS) and lung injury which increases the risk of lung infection and death. Mitochondrial DNA (mtDNA) plays a role in SIRS and lung injury in patients with multi-trauma, and also in patients with hip fractures. This study evaluated the potential value of plasma mtDNA in the early prognosis of lung injury in elderly fracture patients.

METHODS

This study enrolled 156 elderly patients with intertrochanteric fracture. Plasma mtDNA, IL-6, IL-10, prostaglandin E2 (PGE2) levels were measured at admission. Sixty-one and 31 patients were diagnosed with systemic inflammatory response syndrome (SIRS) and lung injury, respectively.

RESULTS

Plasma mtDNA levels were higher in hip fracture patients compared to healthy controls (P<0.001) and significantly higher in the lung injury subgroup compared to the lung injury absent subgroup (P<0.001). MtDNA levels were correlated with the SIRS score (r=0.446, P<0.001), IL-6 (r=0.506, P<0.001), IL-10 (r=0.523, P<0.001), and PGE2 (r=0.360, P<0.001). Logistic regression analysis revealed that plasma mtDNA, IL-6, PGE2 and SIRS score were independent predictors of the risk of lung injury.

CONCLUSION

Plasma mtDNA release induced by hip fracture in elderly patients, might be an early predictor of lung injury in these patients.