Abstract

INTRODUCTION Iron chelation therapy (ICT) is essential to prevent complications of iron overload in patients with transfusion-dependent thalassaemia. However, there is currently no standard for how to best measure adherence to ICT, nor what level of adherence necessitates concern for poor outcomes, especially in paediatric patients. The objectives of this review are to identify rates of adherence to ICT, predictors of adherence, methods of measurement, and adherence-related health outcomes in children and adolescents. METHODS This review covers the literature published between 1980 and 2020 on ICT in thalassaemia that assessed adherence or compliance. Included studies reflect original research. The preferred reporting items of systematic reviews and meta-analyses (PRISMA) guidelines were followed for reporting results, and the findings were critically appraised with the Oxford Centre for Evidence-based Medicine criteria. RESULTS Of the 543 articles, 37 met the inclusion criteria. The most common methods of assessing adherence included patient self-report (n = 15/36, 41.7%), and pill count (n = 15/36, 41.7%), followed by subcutaneous medication monitoring (5/36, 13.8%) and prescription refills (n = 4/36, 11.1%). Study sizes ranged from 7 to 1115 participants. Studies reported adherence either in "categories" with different levels of adherence (n = 29) or "quantitatively" as a percentage of medication taken out of those prescribed (n = 7). Quantitatively, the percentage of adherence varied from 57% to 98.4% with a median of 89.5%. Five studies focussed on interventions, four of which were designed to improve adherence. Studies varied in sample size and methods of assessment, which prohibited performing a meta-analysis. CONCLUSIONS Due to a lack of clinical consensus on how adherence is defined, it is difficult to compare adherence to ICT in different studies. Future studies should be aimed at creating guidelines for assessing adherence and identifying suboptimal adherence. These future efforts will be crucial in informing evidence-based interventions to improve adherence and health outcomes in thalassaemia patients.Key messagesPredictive factors associated with ICT adherence in the paediatric population include age, social perception of ICT, social support, and side effects/discomfort.Increased adherence in the paediatric population is associated with decreased serum ferritin and improved cardiac, hepatic, and endocrine outcomes.Inadequate adherence to ICT is associated with increased lifetime health costs.There are few studies that focussed on interventions to increase adherence in the paediatric population, and the studies that do exist all focussed on different types of interventions; successful interventions focussed on consistent, long-term engagement with patients.

Abstract

OBJECTIVES Sickle cell disease (SCD) is a complex, chronic condition that impairs health-related quality of life of affected individuals and their caregivers. As curative therapies emerge, comprehensive cost-effectiveness models will inform their value. These models will require descriptions of health states and their corresponding utility values that accurately reflect health-related quality of life over the disease trajectory. The objectives of this systematic review were to develop a catalog of health state utility (HSU) values for SCD, identify research gaps, and provide future directions for preference elicitation. METHODS Records were identified through searches of PubMed and Embase, Tufts Medical Center Cost-Effectiveness Analysis Registry, reference lists of relevant articles, and consultation with SCD experts (2008-2020). We removed duplicate records and excluded ineligible studies. For included studies, we summarized the study characteristics, methods used for eliciting HSUs, and HSU values. RESULTS Five studies empirically elicited utilities using indirect methods (EQ-5D) (n = 3) and Short Form-6 Dimension (n = 2); these represent health states associated with general SCD (n = 1), SCD complications (n = 2), and SCD treatments (n = 3). Additionally, we extracted HSUs from 7 quality-adjusted life-years-based outcome research studies. The HSU among patients with general SCD without specifying complications ranged from 0.64 to 0.887. Only 36% of the HSUs used in the quality-adjusted life-year-based outcomes research studies were derived from individuals with SCD. No study estimated HSUs in caregivers. CONCLUSIONS There is a dearth of literature of HSUs for use in SCD models. Future empirical studies should elicit a comprehensive set of HSUs from individuals with SCD and their caregivers.

Abstract

The onset of respiratory distress and acute lung injury (ALI) following a blood transfusion is known as transfusion-related acute lung injury (TRALI), although its pathophysiology remains unknown. Even though sickle cell disease (SCD) has been studied for more than a century, few therapeutic and management strategies adequately address the emergence of TRALI. TRALI, an immune-mediated transfusion response that can result in life-threatening consequences, is diagnosed based on clinical signs and symptoms. Early detection and treatment increase the chances of survival and, in most cases, result in a complete recovery. Our objective is to provide a firm grasp of the present status of SCD-related TRALI care and therapy. After exploring multiple databases, this study offers evidence-based guidelines to aid clinicians and other healthcare professionals make decisions concerning transfusion assistance for SCD and the management of transfusion-related complications. Other risk factors for acute lung injury including sepsis aspiration should be ruled out throughout the diagnostic process. Several recent studies have shown that immunotherapy or immunological targets can effectively prevent these complications. Red cell transfusions, red cell antigen matching optimization, and iron chelation can also help reduce negative consequences. It is to be noted that poor clinical outcomes can be avoided by early detection and treatment of hemolytic transfusion reactions. Finally, preventing the onset of TRALI may be the most effective therapeutic strategy for SCD patients who rely on blood transfusions for survival.

Abstract

Myelodysplastic syndromes (MDS) are a group of malignant hematologic diseases characterized by ineffective hematopoiesis, which may lead to chronic anemia and transfusion dependency, with up to 30% of patients progressing to acute myeloid leukemia (AML). Studies suggest transfusion dependency may impact overall survival (OS); however, there is a lack of evidence concerning the association between transfusion status (TS) and OS in patients with MDS who become transfusion independent (TI) after treatment. In addition, the holistic impact of TS on other clinical, economic, and humanistic outcomes has not been well understood. We conducted a systematic literature review (SLR) to understand this impact. Ten studies were included and showed consistent decrease in OS in transfusion dependent (TD) compared with TI patients. These findings were confirmed by a meta-analysis (MA) reporting better OS prognosis for TI patients. A second SLR was conducted to understand the association between TS and other clinical, economic, and humanistic outcomes. Twenty-eight studies were included and showed better prognosis for other outcomes, including AML progression and leukemia-free survival for TI patients. Risk of AML progression and cumulative non-leukemic death assessed by the MA showed a trend toward worse prognosis and higher risk of AML progression for TD patients. Lower healthcare resource utilization, better quality of life, and reduced non-leukemic death for TI patients were observed. Studies not eligible for MA also showed better clinical, economic and humanistic outcomes for TI patients. These findings contribute to understanding the association between transfusion dependence and OS among other outcomes in patients with MDS.

Abstract

BACKGROUND AND OBJECTIVES Iron overload in thalassaemia is a crucial prognostic factor and a major cause of death due to heart failure or arrhythmia. Therefore, previous research has recommended amlodipine as an auxiliary treatment to current chelating agents for reducing iron overload in thalassaemia patients. MATERIALS AND METHODS A systematic review and meta-analysis of the results of three randomized clinical trials evaluating the use of amlodipine in thalassaemia patients through 12 databases were carried out. RESULTS Our final cohort included 130 patients. Insignificant difference in decreasing liver iron concentrations was found between amlodipine and control groups {weighted mean difference = -0·2, [95% confidence interval = (-0·55-0·15), P = 0·26]}. As regards serum ferritin, our analysis also showed no significant difference in serum ferritin between amlodipine and control groups {weighted mean difference [95% confidence interval = -0·16 (-0·51-0·19), P = 0·36]}. Similarly, there was insignificant difference in cardiac T2* between amlodipine and control groups {weighted mean difference [95% confidence interval = 0·34 (-0·01-0·69), P = 0·06]}. CONCLUSIONS Despite the growing evidence supporting the role of amlodipine in reducing iron overload in thalassaemia patients, our meta-analysis did not find that evidence collectively significant. The results of our simulation suggest that when more data are available, a meta-analysis with more randomized clinical trials could provide more conclusive insights.

Abstract

BACKGROUND Red blood cell (RBC) transfusions have been implicated in the development of necrotizing enterocolitis (NEC) in premature infants. Some evidence exists to support that withholding feedings during transfusion reduces the risk of subsequent NEC development. PURPOSE To review the most recent literature on this topic to determine best evidence-based practice regarding withholding or not withholding feedings during RBC transfusions. METHODS/SEARCH STRATEGY Four databases were searched using keywords and MeSH terms including "necrotizing enterocolitis," "NEC," "NPO," and "transfusion," with specifications limiting the search to articles published in the last 10 years and limiting the population to neonates. FINDINGS Four studies did not demonstrate a reduction in transfusion-associated necrotizing enterocolitis (TANEC) with the implementation of feeding protocols during packed red blood cell (PRBC) transfusions. One study concluded that it could not confirm the benefit of withholding feeds during transfusion to reduce the risk of TANEC. A 2020 randomized controlled trial (RCT) found no difference in splanchnic oxygenation when enteral feeds are withheld, continued, or restricted during a PRBC transfusion. Holding feedings during PRBC transfusions did not result in adverse nutritional outcomes. IMPLICATIONS FOR PRACTICE To determine best evidence-based practice surrounding feeding protocols during RBC transfusions in very low-birth-weight and premature infants less than 37 weeks' gestation. IMPLICATIONS FOR RESEARCH It is recommended that large, multicentered, adequately powered RCTs be conducted in this area. Individual institutions should standardize their practice to improve quality, safety, and patient outcomes.

Abstract

BACKGROUND Despite common use in clinical practice, the impact of blood transfusions on prognosis among patients with lung cancer remains unclear. The purpose of the current study is to perform an updated systematic review and meta-analysis to evaluate the influence of blood transfusions on survival outcomes of lung cancer patients. METHODS We searched PubMed, Embase, Cochrane Library, and Ovid MEDLINE for publications illustrating the association between blood transfusions and prognosis among people with lung cancer from inception to November 2019. Overall survival (OS) and disease-free survival (DFS) were the outcomes of interest. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the random-effects model. Study heterogeneity was evaluated with the I(2) test. Publication bias was explored via funnel plot and trim-and-fill analyses. RESULTS We included 23 cohort studies with 12,175 patients (3,027 cases and 9,148 controls) for meta-analysis. Among these records, 22 studies investigated the effect of perioperative transfusions, while one examined that of transfusions during chemotherapy. Two studies suggested the possible dose-dependent effect in accordance with the number of transfused units. In pooled analyses, blood transfusions deleteriously influenced both OS (HR=1.35, 95% CI: 1.14-1.61, P<0.001, I(2)=0%) and DFS (HR=1.46, 95% CI: 1.15-1.86, P=0.001, I(2)=0%) of people with lung cancer. No evidence of significant publication bias was detected in funnel plot and trim-and-fill analyses (OS: HR=1.26, 95% CI: 1.07-1.49, P=0.006; DFS: HR=1.35, 95% CI: 1.08-1.69, P=0.008). CONCLUSIONS Blood transfusions were associated with decreased survival of patients with lung cancer.

Abstract

Allogenic red blood cell transfusions exert a potential detrimental effect on the survival when delivered to cancer patients undergoing surgery with curative intent. We performed a systematic review and meta-analysis to assess the association between perioperative allogenic red blood cell transfusions and risk of death as well as relapse after surgery for localized solid tumors. PubMed, the Cochrane Library, and EMBASE were searched from inception to March 2019 for studies reporting the outcome of patients receiving transfusions during radical surgery for non-metastatic cancer. Risk of death and relapse were pooled to provide an adjusted hazard ratio with a 95% confidence interval [hazard ratio (HR) (95% confidence interval {CI})]. Mortality and relapse associated with perioperative transfusion due to cancer surgery were evaluated among participants (n = 123 studies). Overall, RBC transfusions were associated with an increased risk of death [HR = 1.50 (95% CI 1.42-1.57), p < 0.01] and relapse [HR = 1.36 (95% CI 1.26-1.46), p < 0.01]. The survival was reduced even in cancer at early stages [HR = 1.45 (1.36-1.55), p < 0.01]. In cancer patients undergoing surgery, red blood cell transfusions reduced the survival and increased the risk of relapse. Transfusions based on patients' blood management policy should be performed by applying a more restrictive policy, and the planned preoperative administration of iron, if necessary, should be pursued.

Abstract

Red blood cell (RBC) alloimmunization is a serious complication of blood transfusions, challenging selection of compatible units for future transfusions. Genetic characteristics may be associated with the risk of RBC alloimmunization and may therefore serve to identify high-risk patients. The aim of this systematic review was to summarize the available evidence on genetic risk factors for RBC alloimmunization. Electronic databases were searched up to April 2020 for studies (Search terms included transfusion, alloimmunization and genetic). A total of 2581 alloimmunized cases and 26,558 controls were derived from 24 studies. The alleles that were most frequently studied and that demonstrated significant associations in a meta-analysis with alloimmunization to the Duffy(a) antigen were HLA-DRB1*04 (Odds Ratio 7.80 (95%CI 4.57-13.33)), HLA-DRB1*15 (OR 3.76 (95%CI 2.14-6.59)), and HLA-DRB1*03 (OR 0.12 (95%CI 0.05-0.29)). Furthermore, significant associations with anti-K formation was found for the alleles HLA-DRB1*10 (OR 2.64 (95%CI 1.41-4.95)), HLA*DRB1*11 (OR 2.11, (95%CI 1.34-3.32)), and HLA-DRB1*13 (OR 1.71 (95%CI 1.26-2.33)). Overall, the available evidence was of moderate to low quality, hampering interpretation of reported results. There is an urgent need for high quality evidence on genetic risk factors for RBC alloimmunization.

Abstract

BACKGROUND Anti-allergic agents (e.g. dexamethasone, chlorpheniramine or promethazine) are commonly administered to patients prior to blood product transfusions. However, the use of these agents is largely experience-based instead of evidence-based. This meta-analysis aimed to explore the evidence behind using anti-allergic agents to attenuate transfusion reactions. MATERIALS AND METHODS The Pubmed, EMBASE, Cochrane Library, Wanfang, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biomedical literature (CMB) databases were all queried for related articles. Data from groups treated with and without anti-allergic agents were collected for meta-analysis using RevMan 5.3. Baseline characteristics and univariate statistics between groups were compared using SPSS 19.0. RESULTS Eight eligible articles (six case control studies and two randomized controlled trials, all with high risks of bias) were identified (22060 total cases). Administered anti-allergic agents in these studies only included dexamethasone, chlorpheniramine or promethazine. Baseline characteristics showed no significant age or gender differences between treatment or control groups. There were no significant differences between the pooled experimental or control groups (for each of the three medications) in terms of fever, pruritis, rash, airway spasm or overall transfusion reaction rates. CONCLUSION There is no evidence that dexamethasone, chlorpheniramine or promethazine can prevent transfusion reactions. Avoiding the arbitrary use of such anti-allergic agents before blood transfusions may potentially avoid needless adverse drug reactions.