Case series: coronavirus disease 2019 infection as a precipitant of atypical hemolytic uremic syndrome: two case reports.

BACKGROUND: Atypical hemolytic uremic syndrome is an exceedingly rare thrombotic microangiopathy caused by accelerated activation of the alternative complement pathway. CASE PRESENTATION: Here, we report two cases of patients presenting with suspected atypical hemolytic uremic syndrome precipitated by coronavirus disease 2019 infection. The first patient, a 25-year-old Hispanic male, had one prior episode of thrombotic microangiopathy presumed to be atypical hemolytic uremic syndrome precipitated by influenza A, and re-presented with thrombocytopenia, microangiopathic hemolytic anemia, nonoliguric renal failure, and normal ADAMTS13 activity, with confirmed coronavirus disease 2019 positivity. The second patient, a 31-year-old Caucasian female, had no personal history of thrombotic microangiopathy, though reported a family history of suspected atypical hemolytic uremic syndrome. She presented with similar laboratory derangements, oliguric renal failure requiring hemodialysis, and confirmed coronavirus disease 2019 positivity. Both patients were treated with eculizumab with complete resolution of their hematologic and renal complications. CONCLUSION: To our knowledge, this represents the largest case series of atypical hemolytic uremic syndrome precipitated by coronavirus disease 2019 in adults.

Post-transplant lymphoproliferative disorders (PTLD)-from clinical to metabolic profiles-a single center experience and review of literature.

Post-transplant lymphoproliferative disorders (PTLD) are among the most serious complications after solid organ transplantation (SOT). Monomorphic diffuse large B-cell lymphoma (DLBCL) is the most common subtype of PTLD. Historically, outcomes of PTLD have been poor with high mortality rates and allograft loss, although this has improved in the last 10 years. Most of our understanding about PTLD DLBCL is extrapolated from studies in non-PTLD DLBCL, and while several clinical factors have been identified and validated for predicting non-PTLD DLBCL outcomes, the molecular profile of PTLD DLBCL has not yet been characterized. Compartment-specific metabolic reprograming has been described in non-PTLD DLBCL with a lactate uptake metabolic phenotype with high monocarboxylate transporter 1 (MCT1) expression associated with worse outcomes. The aim of our study was to compare the outcomes of PTLD in our transplant center to historic cohorts, as well as study a subgroup of our PTLD DLBCL tumors and compare metabolic profiles with non-PTLD DLBCL. We performed a retrospective single institution study of all adult patients who underwent a SOT between the years 1992-2018, who were later diagnosed with PTLD. All available clinical information was extracted from the patients' medical records. Tumor metabolic markers were studied in a subgroup of PTLD DLBCL and compared to a group of non-PTLD DLBCL. Thirty patients were diagnosed with PTLD following SOT in our center. Median time from SOT to PTLD diagnosis was 62.8 months (IQR 7.6; 134.4), with 37% of patients diagnosed with early PTLD, and 63% with late PTLD. The most common PTLD subtype was DLBCL. Most patients were treated with reduction of their immunosuppression (RIS) including a group who were switched from calcineurin inhibitor (CNI) to mTOR inhibitor based IS, in conjunction with standard anti-lymphoma chemoimmunotherapy. Progression free survival of the PTLD DLBCL cohort was calculated at 86% at 1 year, and 77% at 3 and 5-years, with overall survival of 86% at 1 and 3-years, and 75% at 5 years. Death censored allograft survival in the kidney cohort was 100% at 1 year, and 93% at 3, 5 and 10 years. MCT1 H scores were significantly higher in a subset of the non-PTLD DLBCL patients than in a PTLD DLBCL cohort. Our data is concordant with improved PTLD outcomes in the last 10 years. mTOR inhibitors could be an alternative to CNI as a RIS strategy. Finally, PTLD DLBCL may have a distinct metabolic profile with reduced MCT1 expression compared to non-PTLD DLBCL, but further studies are needed to corroborate our limited cohort findings and to determine if a specific metabolic profile is associated with outcomes.

Delayed onset serotonin syndrome in the setting of polypharmacy.

Serotonin syndrome is a rare but well-known condition that can be life-threatening if not diagnosed early. Onset is usually within 4 to 13 h of starting the offending medication. We present a case of delayed onset of serotonin syndrome that presented after 48 h. Polypharmacy played a role in causing the onset of symptoms. Clinicians should keep a high index of suspicion for serotonin syndrome when dealing with elderly confused patients who take multiple medications even when the onset is delayed or atypical because the outcome can be disastrous.

Phase I/II study of bendamustine in combination with ofatumumab, carboplatin, etoposide (BOCE) for relapsed or refractory aggressive B-cell non-Hodgkin lymphoma.

We developed an outpatient salvage chemotherapy regimen using bendamustine, ofatumumab, carboplatin and etoposide (BOCE) to treat relapsed/refractory non-Hodgkin lymphoma (RR NHL) in a single-center phase I/II study. Primary objectives were safety, tolerability and overall response rate (ORR). Thirty-five RR NHL patients (57% de novo large cell [DLBCL] or grade 3B follicular [FL], 26% transformed DLBCL, 9% grade 3A FL, 3% mantle cell; median age = 62, median prior therapies = 1) were treated. Median follow-up was 24.1 months. ORR was 69% (CR = 49%, PR = 20% [ORR = 70%, CR = 50%, PR = 20% in the de novo DLBCL/grade 3B FL subgroup]). Median progression-free survival was 5.1 months and overall-survival 26.2 months. Twelve patients subsequently underwent stem cell transplantation. The most common non-hematologic grade 3-4 toxicities were neutropenic fever and hypophosphatemia. There were no treatment-related deaths. In conclusion, BOCE is a safe and effective outpatient salvage regimen for patients with RR NHL and serves as an effective bridge to stem cell transplantation.

Obstructive Sleep Apnea: Risk Factor for Arrhythmias, Conduction Disorders, and Cardiac Arrest.

Background Obstructive sleep apnea (OSA) has been described as a risk factor for cardiac arrhythmias. Its association with atrial fibrillation has been established. However, relationships with other arrhythmias and conduction disorders have not been fully studied. Methods We used the National Inpatient Sample database from 2009 to 2011 to explore the relationship between OSA and arrhythmias and conduction disorders. The presence of diagnosis was determined based on the International Classification of Disease-9 (ICD-9) codes. Univariate and multivariate logistic regressions were used to establish mortality risks among all groups. Results Multivariate logistic regression showed increased mortality in patients with OSA in comparison to patients without OSA and patients across all categories of arrhythmias and conduction disorders. One significant finding was the increased association of cardiac arrest in patients with OSA versus patients without OSA (OR: 95.72; CI: 89.13-105.81, p < 0.001). Conclusions OSA is significantly associated with non-atrial fibrillation arrhythmias, conduction disorders, and sudden cardiac arrest. Awareness regarding this association is important for early screening for OSA in obese patients to prevent cardiovascular morbidity and mortality. The use of continuous positive airway pressure (CPAP) might be beneficial against all kinds of arrhythmias and sudden cardiac death.

Influence of abnormal potassium levels on mortality among hospitalized heart failure patients in the US: data from National Inpatient Sample.

Background: Abnormalities in serum potassium levels have been associated with variable mortality risk among hospitalized patients with heart failure (HF). We aim to use a large database study to further characterize risk of mortality, demographic factors, and associated comorbidities among heart failure inpatients. Methods: Our sample population was from the US National Inpatient Sample database from the year 2009-2011. The inclusion criteria used to identify patients was those with a diagnosis of heart failure as per ICD-9 classification. Other demographic factors considered in data collection included income, and cardiac risk factors. Taking these factors into consideration, a univariate association of potassium level and mortality was performed, as well as multivariable logistic regression controlling for demographic factors and associated conditions. Results: Of the 2,660,609 patients who were discharged with a diagnosis of heart failure during this time period, patients with hypokalemia during hospitalization had increased mortality risk (OR: 1.96, 95% CI: 1.91-2.01) when compared with those with hyperkalemia who had decreased inpatient mortality risk OR: 0.94,95% CI: 0.91-0.96) versus those not coded for potassium abnormalities. This finding was significant even regardless of the etiology of the hypokalemia while the hyperkalemic patients were noted to have no difference or a decreased risk in all subtypes and groups. Conclusion: Unlike heart failure patients with hyperkalemia, those with hypokalemia are at an increased inpatient mortality risk. Whether our mortality findings translate to longer-term outpatient settings where significantly less monitoring is possible is a matter for further study.

Association between thyroid abnormalities and hypertension among hospitalized US patients: data from the National Inpatient Sample.

Abnormalities of thyroid, namely hyperthyroidism and hypothyroidism, are both associated with increased risk of hypertension. We utilized the National Inpatient Sample from the years 2012-2014 to explore the risk of thyroid disorders in relation to those without a thyroid diagnosis. We found that hypertension was more commonly associated with hyperthyroidism (odds ratio: 1.18; 95% confidence interval: 1.16-1.21, P<0.0001) than with hypothyroidism (odds ratio: 1.06; 95% confidence interval: 1.06-1.07, P<0.0001) when both were compared with hypertension without a thyroid diagnosis.

Acquired von Willebrand Disease Associated with Monoclonal Gammopathy of Unknown Significance.

We present a case of a 79-year-old male who presented with retroperitoneal hematoma a week after motor vehicle accident. Prior history and family history of bleeding were nonsignificant. His activated partial thromboplastin time was found to be prolonged in the emergency department. Further workup with coagulation studies showed decreased factor VIII, vWF antigen, and vWF:ristocetin cofactor assay, and negative Bethesda assay, indicating acquired von Willebrand disease. Immunofluorescence to find an underlying etiology was suggestive of MGUS. Management of AvWD depends on controlling active bleeding and treating the underlying cause. He was treated with factor VIII, haemate-p, rituximab, two cycles of IVIg, and three weeks of oral steroids.

Spontaneous HIT syndrome post-knee replacement surgery with delayed recovery of thrombocytopenia: a case report and literature review.

Recently published reports have established a heparin-induced thrombocytopenia (HIT)-mimicking thromboembolic disorder without proximate heparin exposure, called spontaneous HIT syndrome. Although the pathophysiology remains unclear, anti-platelet factor 4 (PF4)/heparin antibodies possibly triggered by exposure to knee cartilage glycosaminoglycans or other non-heparin polyanions found on bacterial surfaces and nucleic acids have been postulated. We present a 53-year-old female receiving antithrombotic prophylaxis with aspirin following right total knee replacement surgery (without perioperative or any previous lifetime heparin exposure) who acutely presented with high-risk pulmonary embolism (PE) and right great saphenous vein thrombophlebitis on postoperative day (POD) 14; her platelet count at presentation was 13 × 109/L. Prior to diagnostic consideration of spontaneous HIT syndrome, the patient briefly received unfractionated heparin (UFH) and one dose of enoxaparin. The patient's serum tested strongly positive for anti-PF4/heparin antibodies by two different PF4-dependent enzyme-linked immunosorbent assays (ELISAs) and by serotonin release assay (SRA). Failure of fondaparinux anticoagulation (persisting HIT-associated disseminated intravascular coagulation) prompted switching to argatroban. Severe thrombocytopenia persisted (platelet count nadir, 12 × 109/L, on POD21), and 9 days after starting argatroban symptomatic right leg deep-vein thrombosis (DVT) occurred, prompting switch to rivaroxaban. Thereafter, her course was uneventful, although platelet count recovery was prolonged, reaching 99 × 109/L by POD45 and 199 × 109/L by POD79. The patient's serum elicited strong serotonin release in the absence of heparin (seen even with 1/32 serum dilution) that was enhanced by pharmacological concentrations of UFH (0.1 and 0.3 IU/mL) and fondaparinux (0.1-1.2 µg/mL, i.e., in vitro fondaparinux "cross-reactivity"). Ultimately, platelet count recovery was associated with seroreversion to a negative SRA (documented at POD151). Our literature review identified joint replacement surgery, specifically knee replacement, to be a relatively common trigger of spontaneous HIT syndrome. Further, including our patient case, 5 of 7 patients with spontaneous HIT syndrome post-orthopedic surgery who received treatment with argatroban developed new and/or progressive lower-limb DVT or recurrent PE despite anticoagulation with this parenteral direct thrombin inhibitor, suggesting that this patient population is at high risk of breakthrough thrombotic events despite treatment with this HIT treatment-approved anticoagulant. Our case also illustrates successful outcome with rivaroxaban for treatment of spontaneous HIT syndrome, consistent with emerging literature supporting safety and efficacy of direct oral anticoagulant therapy for treatment of acute HIT.

Life-Threatening Hemopericardium Associated with Rivaroxaban.

Rivaroxaban is a novel oral anticoagulant used in the treatment of venous thromboembolism. The use of this medication has expanded over the recent years with resultant expansion of side effect profile. We present a case of a 56-year-old female who presented with shortness of breath and chest pain 12 weeks after starting rivaroxaban for left upper extremity deep vein thrombosis. She was later diagnosed with spontaneous hemopericardium requiring pericardial fluid drainage. Rarer side effects like this will be encountered more often with the increasing use of novel oral anticoagulants. The clinicians should be cognizant of this entity among patients with shortness of breath and chest pain for timely diagnosis and intervention.

It's not what it looks like: atypical rash in cryoglobulinaemic vasculitis.

A 48-year-old man with a history of intravenous drug use and chronic, untreated hepatitis C presented to the emergency room with acute bilateral lower extremity swelling, erythema and maculopapular rash. Serum C4 levels were low, but dermatology felt the rash was due to venous stasis dermatitis. The patient was discharged with compression stockings, but returned to the hospital 5 days later with no improvement in his symptoms. A more extensive laboratory workup revealed hepatitis C viral load of 4 million, elevated serum cryoglobulins, and skin biopsy showing leucocytoclastic vasculitis. He was treated with oral prednisone, with complete resolution of his symptoms after 2 weeks. He was scheduled for follow-up in gastroenterology clinic for treatment of his hepatitis C for definitive cure of his mixed cryoglobulinaemia, but failed to get insurance authorisation to begin treatment with Harvoni. He presented to the hospital 4 months later with diffuse alveolar haemorrhage.

Burden of hospitalizations related to adverse drug events in the USA: a retrospective analysis from large inpatient database.

PURPOSE: Adverse drug events (ADEs) represent medication-related patient harm, which is associated with significant patient morbidity and mortality. This study was conducted to determine the rate, specific causes, and outcomes of ADE-related hospitalization in the USA. METHODS: We used the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample dataset for the years 2008 to 2011. We selected patients with ADE based on 537 Classification of Diseases-9 codes. Main outcome measures included yearly prevalence, cost, length of stay, and mortality of ADE-related hospitalizations. Calculations were performed on weighted samples, and statistical significance was set at p-value <0.05 (two-tailed). RESULTS: We estimated the total hospitalizations with ADE to be 9 440 757 patients (6.28% of total) from 2008 to 2011. Increasing trend was noted from 2008 (5.97%) to 2011 (6.82%) with an annual percentage change rate of 4.37. Patients with ADE were significantly older (2011: mean age 61.42 vs. 48.65 years) and had more comorbidities. Steroids (14.49%), antineoplastic drugs (13.06%), anticoagulants (11.33%), nonsteroidal anti-inflammatory drugs (8.78%), and opiates/narcotics (6.48%) were the five most common causes of ADE. Patient with ADE stayed 1.89 days [95% confidence interval (CI) (1.79-1.99); p < 0.001] longer, incurred $1851.44 [95%CI ($1613.90-$2088.96), p < 0.001] higher with higher odds of mortality 1.27 [95%CI (1.24-1.29), p < 0.001]. CONCLUSION: Adverse drug event carries a significant burden of inpatient hospital care, incurs more cost, and leads to increased loss of life. Targeted policies to reduce them could potentially help decrease mortality as well as drive down cost. Copyright © 2017 John Wiley & Sons, Ltd.

Takotsubo cardiomyopathy associated with epinephrine use: A systematic review and meta-analysis.

BACKGROUND: Takotsubo cardiomyopathy is a syndrome of transient cardiac dysfunction that is frequently associated with sudden emotional or physical stress. Epinephrine use has been implicated in precipitating Takotsubo cardiomyopathy in multiple case reports and case series. We sought to systematically review the current English literature on this association. METHODS: We searched relevant articles on Takotsubo cardiomyopathy associated with epinephrine administration and extracted data on demographic characteristics, clinical features, investigations and clinical outcomes. RESULTS: We identified total of 41 cases from 36 articles. The mean age of presentation was (47.07±15.73years) with strong female preponderance (83%, P=0.0001). The most common symptom at presentation was chest pain (82%). Mean peak troponin I level was (7.12±11.22ng/ml). The most common EKG abnormality was ST elevation, seen in 40% of patients. The most common finding on echocardiography was apical hypokinesis, seen in 48.78% cases. Patients younger than 45 were less likely to have apical cardiomyopathy (n=5/20, 25%) compared to patients with age >45 (n=14/21, 66%, p value 0.001, OR 0.17). The most common route of administration of epinephrine was intravenous (65.85%). All patients except one survived with complete recovery of systolic function reported in most cases within an average of 14.7days. CONCLUSION: Exposure to epinephrine in clinical practice can trigger Takotsubo cardiomyopathy, which is rapidly reversible with good prognosis in most cases. This review further supports the notion that both exogenous and endogenous catecholamines are associated with the pathogenesis of Takotsubo cardiomyopathy.

Effect of Statins on the Mortality of Bacteremic Patients: A Systematic Review and Meta-analysis of Clinical Trials.

BACKGROUND: Statins modify inflammatory cell signaling during the immune response to infection. This has been considered as a pleotropic effect. Effects of statins in inflammatory conditions such as bacteremia have been found to be controversial. AIMS: We examined the effect of statins on the mortality of bacteremia patients. MATERIALS AND METHODS: Major databases were searched for the pertinent clinical trials. RESULTS: Six cohort studies comprising 7553 patients were included. Hospital mortality was lower (15.36% vs 22.28%) in patients on statin. CONCLUSIONS: There may be a potential role of statins in similar inflammatory and infective conditions.

RS3PE revisited: a systematic review and meta-analysis of 331 cases.

OBJECTIVES: Remitting seronegative symmetrical synovitis with pitting oedema (RS(3)PE) syndrome is a rare inflammatory arthritis, characterised by symmetrical distal synovitis, pitting oedema of the hands and feet, absence of rheumatoid factor, and favourable response to glucocorticoids. The aim of our study is to further delineate the clinical and laboratory features, and response to treatment. METHODS: We performed a systematic electronic search of Medline, PubMed, EMBASE, ACR and EULAR databases for case reports, case series, and related articles of RS(3)PE. Statistical analysis was done comparing categorical variables with Chi-square tests and frequencies of means via t-tests. Binary logistic regression analysis was performed to identify predictors of erosions, recurrence, malignancy and rheumatologic disorders. RESULTS: 331 cases of RS(3)PE were identified from 121 articles. RS(3)PE was found in older patients (71±10.42 years) predominantly in males (n= 211, 63.36%), was symmetrical (n=297/311, 95.50%) involved the hands (n=294/311, 94.53%) A concurrent rheumatologic condition was reported in 22 cases (6.65%), and malignancy in 54 cases (16.31%). Radiographic joint erosions were found in 5.5%. Most patients responded to medium-dose glucocorticoids (16.12±9.5 mg/day). Patients with concurrent malignancy requiring non-significantly higher doses of prednisone (18.12 vs. 15.76 mg, p 0.304) and higher likelihood of recurrence of disease (OR 4.04, 95% CI 1.10-14.88, p=0.03). CONCLUSIONS: The symptoms and unique findings that make up RS(3)PE appear to represent a steroid-responsive disease that may be a harbinger of an underlying malignancy. More study is needed to understand the molecular origins of RS(3)PE in order to determine whether it is a separate disease process. Patients with concurrent cancer tend to have more severe presentations and higher rates of recurrence.

Upper Airway Hematoma Secondary to Warfarin Therapy: A Systematic Review of Reported Cases.

Upper airway hematoma (UAH) is a rare but life-threatening complication of oral anticoagulants requiring early recognition. However, no consensus exists regarding the best approach to treatment. We therefore, sought to systematically review the published literature on UAH to elaborate its demographic and clinical characteristics, treatment, complications, and outcomes. A systematic electronic search of PubMed and EMBASE for case reports, case series, and related articles of UAH related to warfarin published from inception (November 1950) to March 2015 was carried out. Categorical variables were expressed as percentage and continuous variables as mean ± standard deviation (SD). Statistical analysis was done using Statistical Package for the Social Sciences (SPSS) version 20.0. All cases were reported to have UAH as a complication of anticoagulation therapy with warfarin. Demographic and clinical characteristics, treatment, complications and outcomes of UAH were studied. Thirty-eight cases of UAH were identified from 34 reports in the literature. No gender preponderance (male = 52.78%) was seen and the average age of presentation was 60.11 ± 12.50 years. Dysphagia, sore throat, and neck swelling were the most common symptoms and the mean international normalized ratio (INR)at presentation was 8.07 ± 4.04. Most cases had sublingual hematoma (66.57%) followed by retropharyngeal hematoma (27.03%). Of the cases, 48.65% were managed conservatively while the rest underwent either cricothyrotomy or intubation with the time to resolution being 7.69 ± 5.44 days. UAH is a rare butpotentially serious complication of warfarin therapy. It is more common in the elderly population with supratherapeutic INR; inciting events were present in many cases. Overall, it has a good prognosis with significant morbidity present only if concomitant respiratory compromise is present. Reversal of anticoagulation with low threshold for artificial airway placement in the event of airway compromise leads to a favorable outcome in most cases.

Do all patients with acquired methemoglobinemia need treatment? A lesson learnt.

Acquired methemoglobinemia is a medical emergency, and its prompt recognition and treatment can avoid catastrophic complications including death. However, in mild asymptomatic cases without any comorbid conditions, it would be reasonable to simply observe and treat symptomatically to avoid severe treatment-related complications, especially in patients with suspected glucose-6-phosphate dehydrogenase (G6PD) deficiency. We present a case of mild methemoglobinemia in occult G6PD deficiency in which the patient developed hemolysis after treatment with intravenous methylene blue, requiring transfusion.

Thromboprophylaxis with apixaban and the risk of pulmonary embolism in patients undergoing knee replacement surgery.

BACKGROUND: Apixaban, a novel oral anticoagulant, is also used for deep vein thrombosis (DVT) prophylaxis. In this study, we sought to critically evaluate the differences in the rates of symptomatic DVT and bleeding, and analyze the rates of pulmonary embolism (PE) in subgroups of patients from ADVANCE I and II trials given their similar indication and design. METHODS: Studies were identified through electronic literature searches of MEDLINE, clinicaltrial.gov, SCOPUS, and EMBASE up to January 2014. Phase III RCTs involving use of apixaban and enoxaparin for thromboprophylaxis in patients undergoing total knee or hip replacement were included. Study-specific odds ratios were calculated and between-study heterogeneity was assessed using the I (2) statistics. RESULTS: In three studies involving 11,659 patients, the risk of symptomatic DVT (pooled OR 0.38, 95% CI 0.16-0.90, I (2)=0%, p=0.03) and bleeding (pooled OR 0.87, 95% CI 0.77-0.99, I (2)=0%, p=0.03) was less in apixaban group compared to the enoxaparin group. However, it was interesting to note that on subgroup analysis, the risk of PE was higher with apixaban when used for thromboprophylaxis in knee replacement surgery (pooled OR 2.58, 95% CI 1.10-6.04, I (2)=0%, p=0.03). CONCLUSION: Apixaban was found to be associated with lower risk of symptomatic DVT and bleeding compared to enoxaparin when used for thromboprophylaxis in patients undergoing knee and hip replacement surgeries. However, it was associated with higher risk of PE in patients undergoing knee replacement.

Meta-analysis on efficacy and safety of new oral anticoagulants for venous thromboembolism prophylaxis in elderly elective postarthroplasty patients.

The risk of venous thromboembolism (VTE) increases with age. New oral anticoagulants (NOACs) have been increasingly studied for VTE prophylaxis in patients with elective postarthroplasty. Although the elderly population accounts for a significant proportion of patients requiring VTE prophylaxis, safety and efficacy of NOACs in this subgroup for VTE prophylaxis has not been well studied. Relevant studies were identified through electronic literature searches of MEDLINE, EMBASE, Cochrane Library, and ClinicalTrials.gov (from inception to 12 August 2014). Phase III randomized controlled trials that compared NOACs against low-molecular-weight heparin (LMWH) in the prevention of VTE prophylaxis in patients with elective postarthroplasty were included. We defined our elderly population as adults of at least 75 years and assessed the reported safety and efficacy outcomes with NOACs in this population. Study-specific odds ratios (ORs) were calculated and between-study heterogeneity was assessed using the I statistic. In nine trials involving 29 403 patients, the risk of VTE or VTE-related deaths in elderly patients with elective postarthroplasty was similar with NOACs compared with LMWH (OR 0.62, 95% confidence interval 0.30-1.26; P = 0.18; I = 44%) but bleeding risk was significantly lower (OR 0.71, 95% confidence interval 0.53-0.94; P = 0.02; I = 0%). Analysis of individual NOACs showed superior efficacy but similar safety for apixaban when compared with LMWH. Efficacy and safety profiles of rivaroxaban and dabigatran were similar to LMWH. In elderly patients with elective postarthroplasty, NOACs have similar efficacy but superior safety when compared with enoxaparin for VTE prophylaxis.