Association of azithromycin with mortality and cardiovascular events among older patients hospitalized with pneumonia

Association of diabetic retinopathy on all-cause and cause-specific mortality in older adults with diabetes: National Health and Nutrition Examination Survey, 2005-2008

To evaluate the effect of diabetic retinopathy (DR) status or severity on all-cause and cause-specific mortality among diabetic older adults in the United States using the most recent National Health and Nutrition Examination Survey (NHANES) follow-up mortality data. The severity of DR was graded according to the Early Treatment Diabetic Retinopathy Study (ETDRS) grading scale. Multiple covariate-adjusted Cox proportional hazards regression models, Fine and Gray competing risk regression models, and propensity score matching (PSM) methods were used to assess the risk of all-cause and cause-specific mortality in individuals with diabetes. All analyses adopted the weighted data and complex stratified design approach proposed by the NHANES guidelines. Time to death was calculated based on the time between baseline and date of death or December 31, 2019, whichever came first. Ultimately 1077 participants, representing 3,025,316 US non-hospitalized individuals with diabetes, were included in the final analysis. After a median follow-up of 12.24 years (IQR, 11.16-13.49), 379 participants were considered deceased from all-causes, with 43.90% suffering from DR, including mild DR (41.50%), moderate to severe DR (46.77%), and proliferative DR (PDR) (67.21%). DR was associated with increased all-cause, cardiovascular disease (CVD) and diabetes mellitus (DM)-specific mortality, which remained consistent after propensity score matching (PSM). Results of DR grading assessment suggested that the presence of mild, moderate to severe NPDR was significantly associated with increased risk of all-cause and CVD-specific mortality, while the presence and severity of any DR was associated with increased DM-specific mortality, with a positive trend. The presence of DR in elderly individuals with diabetes is significantly associated with the elevated all-cause and CVD mortality. The grading or severity of DR may reflect the severity of cardiovascular disease status and overall mortality risk in patients with diabetes.

Cardiovascular Safety of Azithromycin in Patients Hospitalized With COVID-19: A Prespecified Pooled Analysis of the COALITION I and COALITION II Randomized Clinical Trials

The cardiovascular safety from azithromycin in the treatment of several infectious diseases has been challenged. In this prespecified pooled analysis of 2 multicenter randomized clinical trials, we aimed to assess whether the use of azithromycin might lead to corrected QT (QTc) interval prolongation or clinically relevant ventricular arrhythmias. In the COALITION COVID Brazil I trial, 667 patients admitted with moderate COVID-19 were randomly allocated to hydroxychloroquine, hydroxychloroquine plus azithromycin, or standard of care. In the COALITION COVID Brazil II trial, 447 patients with severe COVID-19 were randomly allocated to hydroxychloroquine alone versus hydroxychloroquine plus azithromycin. The principal end point for the present analysis was the composite of death, resuscitated cardiac arrest, or ventricular arrhythmias. The addition of azithromycin to hydroxychloroquine did not result in any prolongation of the QTc interval (425.8 ± 3.6 ms vs 427.9 ± 3.9 ms, respectively, mean difference -2.1 ms, 95% confidence interval -12.5 to 8.4 ms, p = 0.70). The combination of azithromycin plus hydroxychloroquine compared with hydroxychloroquine alone did not result in increased risk of the primary end point (proportion of patients with events at 15 days 17.2% vs 16.0%, respectively, hazard ratio 1.08, 95% confidence interval 0.78 to 1.49, p = 0.65). In conclusion, in patients hospitalized with COVID-19 already receiving standard-of-care management (including hydroxychloroquine), the addition of azithromycin did not result in the prolongation of the QTc interval or increase in cardiovascular adverse events. Because azithromycin is among the most commonly prescribed antimicrobial agents, our results may inform clinical practice. Clinical Trial Registration: NCT04322123, NCT04321278.

Doxycycline vs azithromycin in patients with scrub typhus: a systematic review of literature and meta-analysis

INTRODUCTION

Scrub typhus is a bacterial mite-borne disease associated with poor clinical outcomes if not treated adequately. The study aimed to compare the time to defervescence, clinical failure, mortality and treatment-related adverse effects of two common drugs (doxycycline and azithromycin) used for its treatment.

METHODOLOGY

This was a systematic review and meta-analysis. All studies up to 20.03.2023 were screened for eligibility in Pubmed and Embase using a search string containing terms related to scrub typhus, doxycycline and azithromycin. After two phases of screening, all comparative studies where doxycycline and azithromycin were used to treat scrub typhus were included. The studies were critically appraised using standardised tools, and a meta-analysis was performed for time to defervescence (primary outcome), clinical failure, mortality and treatment-related adverse effects.

RESULTS

Of 744 articles from two databases, ten were included in the meta-analysis. All but two studies had a high risk of bias. The meta-analysis for time to defervescence had a high heterogeneity and did not show any significant difference between doxycycline and azithromycin arms [Mean difference of -3.37 hours (95%CI: -10.31 to 3.57), p=0.34]. When the analysis was restricted to studies that included only severe scrub typhus, doxycycline was found to have a shorter time to defervescence [mean difference of -10.15 (95%CI: -19.83 to -0.46) hours, p=0.04]. Additionally, there was no difference between the two arms concerning clinical failure, mortality and treatment-related adverse effects.

CONCLUSION

The current data from studies with a high risk of bias did not find statistically significant differences in clinical outcomes between doxycycline and azithromycin for scrub typhus.

Association of retinopathy with risk of all-cause and specific-cause mortality in the National Health and Nutrition Examination Survey, 2005 to 2008

Objective

This study aimed to elucidate the relationship between retinopathy status or severity and the all-cause and specific-cause mortality risk based on the updated National Health and Nutrition Examination Survey (NHANES) database and 2019 Public Access Link mortality file.

Methods

In this prospective cohort study, a total of 6,797 participants aged over 40 years based on NHANES 2005-2008 were analyzed. The severity of retinopathy was classified into 4 grades-no retinopathy, mild non-proliferative retinopathy (NPR), moderate to severe NPR, and proliferative retinopathy (PR). Multiple covariate-adjusted Cox proportional hazards regression models and Fine and Gray competing risk regression models were used to assess the all-cause and cause-specific mortality risks, respectively. The propensity score matching (PSM) approach was also applied additionally to adequately balance between-group covariates to validate our findings.

Results

A final total of 4,808 participants representing 18,282,772 United States (US) non-hospitalized participants were included for analysis, 50.27% were male (n = 2,417), 55.32% were non-hispanic white (n = 2,660), and mean [SE] age, 56.10 [0.40] years. After a median follow-up of 12.24 years (interquartile range, 11.16-13.49 years), 1,164 participants died of all-cause mortality, of which 941 (80.84%) died without retinopathy and 223 (19.16%) died with retinopathy at baseline. The presence of retinopathy was associated with increased all-cause mortality, cardiovascular disease (CVD), and diabetes mellitus (DM)-specific mortality, and the results remain consistent after PSM. Severity analysis showed that only mild NPR was associated with an increased all-cause mortality risk (hazard ratio (HR) = 2.01; 95% confidence interval (CI), 1.00-4.03), while increased CVD and DM-specific mortality risk were associated with all grades of retinopathy and were exponentially greater with increasing retinopathy severity, and the trend test was also significant (P for trend 0.004 and 0.04, respectively).

Discussion

Our findings suggest that the diagnosis of retinopathy is an independent risk factor for all-cause mortality in people over 40 years old. Retinopathy grading is significantly associated with the survival risk of patients with CVD or DM, it can be a valuable predictor in the stratified management and risk warning of CVD or DM patients, as well as in the monitoring of systemic vasculopathy status.

The incidence of acute renal failure and high mortality rate in elderly patients hospitalized with community acquired pneumonia

Community acquired pneumonia is associated with high mortality and health care costs, especially in old age. The clinical presentation of pneumonia in the elderly may be asymptomatic or atypical. One of the known complication is an acute kidney injury. The purpose of our study was to estimate the incidence of this complication in elderly patients hospitalized with pneumonia in our geriatric hospital. From a group of 180 elderly patients hospitalized with community-acquired pneumonia 34.4 % developed acute kidney injury. In this group, 51.6 % of patients died compared to 14.4 % in the group of patients without acute kidney injury (p < 0.001). The lower level of e-GFR was significantly associated with mortality (p < 0.001): out of seven patients with e-GFR level of 15-29 mg/mmol, five patients died (71.4 %). Elderly patients with community-acquired pneumonia suffering acute kidney injury experienced worse in-hospital outcomes; mortality rate was significantly higher in our study. We found a relationship between low level of e-GFR and mortality. Clinicians should be alert for early detection and prevention of kidney injury in patients admitted with pneumonia.

Relationship Between Azithromycin and Cardiovascular Outcomes in Unvaccinated Patients With COVID-19 and Preexisting Cardiovascular Disease

Background Empiric antimicrobial therapy with azithromycin is highly used in patients admitted to the hospital with COVID-19, despite prior research suggesting that azithromycin may be associated with increased risk of cardiovascular events. Methods and Results This study was conducted using data from the ISACS-COVID-19 (International Survey of Acute Coronavirus Syndromes-COVID-19) registry. Patients with a confirmed diagnosis of SARS-CoV-2 infection were eligible for inclusion. The study included 793 patients exposed to azithromycin within 24 hours from hospital admission and 2141 patients who received only standard care. The primary exposure was cardiovascular disease (CVD). Main outcome measures were 30-day mortality and acute heart failure (AHF). Among 2934 patients, 1066 (36.4%) had preexisting CVD. A total of 617 (21.0%) died, and 253 (8.6%) had AHF. Azithromycin therapy was consistently associated with an increased risk of AHF in patients with preexisting CVD (risk ratio [RR], 1.48 [95% CI, 1.06-2.06]). Receiving azithromycin versus standard care was not significantly associated with death (RR, 0.94 [95% CI, 0.69-1.28]). By contrast, we found significantly reduced odds of death (RR, 0.57 [95% CI, 0.42-0.79]) and no significant increase in AHF (RR, 1.23 [95% CI, 0.75-2.04]) in patients without prior CVD. The relative risks of death from the 2 subgroups were significantly different from each other (Pinteraction=0.01). Statistically significant association was observed between AHF and death (odds ratio, 2.28 [95% CI, 1.34-3.90]). Conclusions These findings suggest that azithromycin use in patients with COVID-19 and prior history of CVD is significantly associated with an increased risk of AHF and all-cause 30-day mortality. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT05188612.

ERS/ESICM/ESCMID/ALAT guidelines for the management of severe community-acquired pneumonia

PURPOSE

Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and whilst European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP.

METHODS

The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations.

RESULTS

Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions.

CONCLUSIONS

In these international guidelines, ERS, ESICM, ESCMID, and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment, and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.

Guideline-Concordant Antibiotic Therapy for the Hospital Treatment of Community-Acquired Pneumonia and 1-Year All-Cause and Cardiovascular Mortality in Older Adult Patients Surviving to Discharge

BACKGROUND

Selection of empiric antibiotic treatment for community-acquired pneumonia (CAP) that is concordant with clinical practice guidelines has been associated with improved short-term outcomes of this infection, but whether it is also associated with longer-term outcomes is unknown.

RESEARCH QUESTION

Is guideline-concordance of the initial antibiotic treatment given to older adult patients hospitalized with CAP associated with the 1-year all-cause and cardiovascular mortality risk of those patients who survive hospitalization for this infection?

STUDY DESIGN AND METHODS

A total of 1,909 older (> 65 years of age) patients were identified who survived hospitalization for CAP at The Ottawa Hospital (Ontario, Canada) between 2004 and 2015. Linking patients' information to hospital and provincial data sets, this study analyzed whether the selection of the initial antibiotic therapy for their CAP was concordant with current clinical practice guidelines, and whether guideline-concordance was associated with 1-year all-cause and cardiovascular mortality following their index CAP hospitalization. Adjustments were made for the patients' overall 1-year expected death risk; CAP severity; and history of previous pneumonia admissions, myocardial infarction, heart failure, or cerebrovascular disease.

RESULTS

Selection of guideline-concordant antibiotic therapy was associated with a trend towards lower all-cause mortality at 1 year post-CAP (hazard ratio, 0.82; 95% CI, 0.65-1.04; P = .099). Furthermore, the use of guideline-concordant antibiotic therapy was associated with a significant almost 50% reduction in cardiovascular death risk 1 year following CAP admission (hazard ratio, 0.53; 95% CI, 0.34-0.80; P = .003).

INTERPRETATION

Use of guideline-concordant antibiotic therapy for CAP treatment in older hospitalized patients is associated with a significant reduction in the risk of cardiovascular death at 1 year post-CAP. This finding further supports current clinical practice guideline recommendations for CAP treatment.

Impact of macrolide treatment on long-term mortality in patients admitted to the ICU due to CAP: a targeted maximum likelihood estimation and survival analysis

INTRODUCTION

Patients with community-acquired pneumonia (CAP) admitted to the intensive care unit (ICU) have high mortality rates during the acute infection and up to ten years thereafter. Recommendations from international CAP guidelines include macrolide-based treatment. However, there is no data on the long-term outcomes of this recommendation. Therefore, we aimed to determine the impact of macrolide-based therapy on long-term mortality in this population.

METHODS

Registered patients in the MIMIC-IV database 16 years or older and admitted to the ICU due to CAP were included. Multivariate analysis, targeted maximum likelihood estimation (TMLE) to simulate a randomised controlled trial, and survival analyses were conducted to test the effect of macrolide-based treatment on mortality six-month (6 m) and twelve-month (12 m) after hospital admission. A sensitivity analysis was performed excluding patients with Pseudomonas aeruginosa or MRSA pneumonia to control for Healthcare-Associated Pneumonia (HCAP).

RESULTS

3775 patients were included, and 1154 were treated with a macrolide-based treatment. The non-macrolide-based group had worse long-term clinical outcomes, represented by 6 m [31.5 (363/1154) vs 39.5 (1035/2621), p < 0.001] and 12 m mortality [39.0 (450/1154) vs 45.7 (1198/2621), p < 0.001]. The main risk factors associated with long-term mortality were Charlson comorbidity index, SAPS II, septic shock, and respiratory failure. Macrolide-based treatment reduced the risk of dying at 6 m [HR (95% CI) 0.69 (0.60, 0.78), p < 0.001] and 12 m [0.72 (0.64, 0.81), p < 0.001]. After TMLE, the protective effect continued with an additive effect estimate of - 0.069.

CONCLUSION

Macrolide-based treatment reduced the hazard risk of long-term mortality by almost one-third. This effect remains after simulating an RCT with TMLE and the sensitivity analysis for the HCAP classification.

Evaluating the inhibitory effect of resveratrol on the multiplication of several Babesia species and Theileria equi on in vitro cultures, and Babesia microti in mice

Introduction: Histone post-translational modification is one of the most studied factors influencing epigenetic regulation of protozoan parasite gene expression, which is mediated by histone deacetylases (KDACs) and acetyltransferases (KATs). Objective and methods: The present study investigated the role of resveratrol (RVT) as an activator of histone deacetylases in the control of various pathogenic Babesia sp. and Theileria equi in vitro, as well as B. microti infected mice in vivo using fluorescence assay. Its role in mitigating the side effects associated with the widely used antibabesial drugs diminazene aceturate (DA) and azithromycin (AZM) has also been investigated. Results: The in vitro growth of B. bovis, B. bigemina, B. divergens, B. caballi and Theileria equi (T. equi) was significantly inhibited (P < 0.05) by RVT treatments. The estimated IC50 values revealed that RVT has the greatest inhibitory effects on B. bovis growth in vitro, with an IC50 value of 29.51 ± 2.46 µM. Reverse transcription PCR assay showed that such inhibitory activity might be attributed to resveratrol's stimulatory effect on B. bovis KDAC3 (BbKADC3) as well as its inhibitory effect on BbKATS. RVT causes a significant decrease (P < 0.05) in cardiac troponin T (cTnT) levels in heart tissue of B. microti- infected mice, thereby indicating that RVT may play a part in reducing the cardiotoxic effects of AZM. Resveratrol showed an additive effect with imidocarb dipropionate in vivo. Treatment of B. microti-infected mice with a combined 5 mg/kg RVT and 8.5 mg/kg ID resulted in an 81.55% inhibition at day 10 postinoculation (peak of parasitemia). Conclusion: Our data show that RVT is a promising antibabesial pharmacological candidate with therapeutic activities that could overcome the side effects of the currently used anti-Babesia medications.

Impact of Administering Intravenous Azithromycin within 7 Days of Hospitalization for Influenza Virus Pneumonia: A Propensity Score Analysis Using a Nationwide Administrative Database

The potential antimicrobial and anti-inflammatory effectiveness of azithromycin against severe influenza is yet unclear. We retrospectively investigated the effect of intravenous azithromycin administration within 7 days of hospitalization in patients with influenza virus pneumonia and respiratory failure. Using Japan's national administrative database, we enrolled and classified 5066 patients with influenza virus pneumonia into severe, moderate, and mild groups based on their respiratory status within 7 days of hospitalization. The primary endpoints were total, 30-day, and 90-day mortality rates. The secondary endpoints were the duration of intensive-care unit management, invasive mechanical ventilation, and hospital stay. The inverse probability of the treatment weighting method with estimated propensity scores was used to minimize data collection bias. Use of intravenous azithromycin was proportional to the severity of respiratory failure (mild: 1.0%, moderate: 3.1%, severe: 14.8%). In the severe group, the 30-day mortality rate was significantly lower with azithromycin (26.49% vs. 36.65%, p = 0.038). In the moderate group, the mean duration of invasive mechanical ventilation after day 8 was shorter with azithromycin; there were no significant differences in other endpoints between the severe and moderate groups. These results suggest that intravenous azithromycin has favorable effects in patients with influenza virus pneumonia using mechanical ventilation or oxygen.

ERS/ESICM/ESCMID/ALAT guidelines for the management of severe community-acquired pneumonia

BACKGROUND

Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and while European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP.

MATERIALS AND METHODOLOGY

The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations.

RESULTS

Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions.

CONCLUSIONS

In these international guidelines, ERS, ESICM, ESCMID and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.

Safety and Tolerability of Antimicrobial Agents in the Older Patient

Older patients are at high risk of infections, which often present atypically and are associated with high morbidity and mortality. Antimicrobial treatment in older individuals with infectious diseases represents a clinical challenge, causing an increasing burden on worldwide healthcare systems; immunosenescence and the coexistence of multiple comorbidities determine complex polypharmacy regimens with an increase in drug-drug interactions and spread of multidrug-resistance infections. Aging-induced pharmacokinetic and pharmacodynamic changes can additionally increase the risk of inappropriate drug dosing, with underexposure that is associated with antimicrobial resistance and overexposure that may lead to adverse effects and poor adherence because of low tolerability. These issues need to be considered when starting antimicrobial prescriptions. National and international efforts have been made towards the implementation of antimicrobial stewardship (AMS) interventions to help clinicians improve the appropriateness and safety of antimicrobial prescriptions in both acute and long-term care settings. AMS programs were shown to decrease consumption of antimicrobials and to improve safety in hospitalized patients and older nursing home residents. With the abundance of antimicrobial prescriptions and the recent emergence of multidrug resistant pathogens, an in-depth review of antimicrobial prescriptions in geriatric clinical practice is needed. This review will discuss the special considerations for older individuals needing antimicrobials, including risk factors that shape risk profiles in geriatric populations as well as an evidence-based description of antimicrobial-induced adverse events in this patient population. It will highlight agents of concern for this age group and discuss interventions to mitigate the effects of inappropriate antimicrobial prescribing.

Magnitude of Coagulation Abnormalities and Associated Factors Among Patients with Heart Diseases at the University of Gondar Comprehensive Specialized Hospital

Background

Heart disease is a leading cause of hospitalization, death, and poor physical function due to comorbid conditions such as atrial fibrillation and stroke. It affects the blood hemostatic system, vasculature, and flow dynamics, causing both arterial and venous thrombosis. Thus, this study aimed to determine the magnitude of coagulation abnormalities among patients with heart disease attending the University of Gondar Comprehensive Specialized hospital.

Methods

A cross-sectional study was conducted on a total of 98 patients with heart disease. Pretested structured questionnaires were used to collect data on socio-demographic and clinical variables. About 6 mL of venous blood was collected with the vacutainer method and analyzed using Huma cue-due plus and Sysmex KX-21N hematology analyzers for assessing coagulation abnormalities. Stool samples were processed via a direct wet mount. Thin and thick blood films were examined to assess malaria parasites. Data was entered into EPI-Info version 3.5.3 and then transported to SPSS version 20 for analysis. Descriptive statistics were summarized using frequency and percentage. Univariate and multivariate logistic regression models were fitted to identify factors associated with coagulopathy. P-value <0.05 was considered to be statistically significant.

Results

The overall magnitude of coagulation abnormalities (thrombocytopenia, prolonged prothrombin time, and activated partial thromboplastin time) in patients with heart diseases was 85.7% (95% CI: 81.96, 89.45). Besides, prolonged prothrombin time, prolonged activated partial thromboplastin time, and thrombocytopenia were detected in 83.7%, 33.7%, and 12.2% of the study participants, respectively. Participants who are taking medications for chronic disease (AOR = 0.17; 95% CI: 0.04, 0.69), participants with stroke (AOR = 20; 95% CI: 14.7, 35), and participants taking antibiotics (AOR = 8.17; 95% CI: 1.66, 40.27) were significantly associated with prolonged coagulation time.

Conclusion

This study showed that patients with heart disease had prolonged prothrombin time, activated partial thromboplastin time, and thrombocytopenia. Therefore, coagulation parameters are required to be checked regularly to monitor coagulation disorders and their complications in heart disease patients.

Safety profile of hydroxychloroquine used off‐label for the treatment of patients with COVID‐19: A descriptive study based on EudraVigilance data

At the beginning of the COVID‐19 pandemic, worldwide attempts were made to identify potential drugs effective against the COVID‐19. Hydroxychloroquine was among the first receiving attention. However, following its use in therapy, it has been shown that hydroxychloroquine was not only ineffective but probably, due to its known side effects, even responsible of increased mortality of patients. The objective of this study was to review the safety profile of hydroxychloroquine used off‐label for the treatment of COVID‐19. We analyze the reports of suspected adverse drug reactions (ADRs) collected in EudraVigilance, the European database of ADR reports. We collected 2266 reports for 2019 and 6525 for 2020. The most reported ADRs during 2020 were those relating to cardiac, hepatic, renal toxicity such as QT prolongation with 400 cases in 2020 (of which, 345 cases—9.97%—with COVID‐19 as a therapeutic indication) versus 1 case only in 2019 (0.01%), long QT syndrome: 38 cases in 2020 (36 as COVID‐19 treatment) versus 0 in 2019, hepatitis: 13 cases in 2019 (0.11%) and 132 in 2020, and 32 cases (24, 0.69%) of acute kidney injury in 2020 and only 3 cases in 2019. Moreover, some important vision‐related ADRs also increased significantly during 2020, such as retinal toxicity with 92 cases in 2020 versus 7 in 2019. Even though with its intrinsic limitations, our results may be added to the most recent scientific evidence to confirm the unfavorable risk profile of hydroxychloroquine in its off‐label use in the treatment of COVID‐19 disease.

The Acute Effects of Azithromycin Use on Cardiovascular Mortality as Compared with Amoxicillin-Clavulanate in United States Veterans

PURPOSE

Azithromycin is a common first-line antibiotic for respiratory infection; however, there is conflicting evidence regarding risk of cardiovascular death. We assessed cardiovascular and non-cardiovascular mortality associated with azithromycin versus amoxicillin-clavulanate among United States (US) Veterans treated for non-ear-nose-throat respiratory infection ("respiratory") or ear-nose-throat infection indication.

METHODS

Electronic health record data from the US Veterans Health Administration database was used to identify Veterans (30-74 years) with outpatient dispensings of oral azithromycin versus amoxicillin-clavulanate for respiratory or ear-nose-throat infection (01/01/2000-12/31/2014). Outcomes assessed were risk of cardiovascular death and non-cardiovascular death within 1-5 and 6-10 days post-dispensing. Inverse probability of treatment-weighted proportional hazards models and binomial regression models were used to estimate hazard ratios (HR) and compute risk differences (RD) per million courses of therapy. Cardiac death (subset of cardiovascular death) was assessed in sensitivity analyses.

RESULTS

There were 629,345 azithromycin and 168,429 amoxicillin-clavulanate dispensings for respiratory indications, 143,783 azithromycin, and 203,142 amoxicillin-clavulanate dispensings for ear-nose-throat indications. For respiratory indications, azithromycin was not associated with significantly different risk of cardiovascular death versus amoxicillin-clavulanate within 1-5 days post-dispensing (HR [95% confidence interval (CI)]: 1.12 [0.63-2.00]; RD [95%CI]: 11 [-43 - +64] deaths/million courses of therapy). No elevated risk for azithromycin was found for ear-nose-throat indications. Pooled results for both indications via meta-analysis showed no association between antibiotics and cardiovascular mortality. There was no significant difference in risk of non-cardiovascular or cardiac death between antibiotics post-dispensing.

CONCLUSION

Azithromycin was not associated with elevated risk of cardiovascular or non-cardiovascular death versus amoxicillin-clavulanate among US Veterans. This article is protected by copyright. All rights reserved.

Comparative safety of inhaled corticosteroids and macrolides in Medicare enrollees with bronchiectasis

Introduction

Bronchiectasis is an increasingly common chronic inflammatory airway disease. We evaluated secondary safety outcomes in a comparative effectiveness study of chronic inhaled corticosteroids (ICS) and macrolide monotherapy in bronchiectasis patients.

Methods

We conducted a retrospective study using US Medicare Parts A, B and D (but not C) 2006–2014 datasets. Among those with a pulmonologist-associated bronchiectasis claim (ICD-9-CM 494.0 or 494.1), without cystic fibrosis, we identified the first new use of either chronic (>28 days) ICS or macrolide monotherapy. For each drug exposure, we calculated crude incidence rates of the secondary safety outcomes: arrhythmia, myocardial infarction, sensorineural hearing loss, hip fracture and opportunistic infections. We calculated a propensity score (PS) for ICS use using demographic, clinical and utilisation characteristics and compared risks of macrolides versus ICS for each outcome using PS decile-adjusted Cox regression models.

Results

Of 285 043 Medicare patients with bronchiectasis, we identified 6500 (2%) macrolide and 83 589 (29%) ICS new users. Key covariates were balanced across exposure groups within decile. Myocardial infarction, hip fracture and opportunistic infection were not significantly associated with treatment. Macrolides were associated with a decreased risk of arrhythmia (adjusted hazard ratio (aHR) 0.87, 95% CI 0.80–0.94) and an increased risk of sensorineural hearing loss (aHR 1.38, 95% CI 1.56–1.22) compared to ICS.

Conclusions

Macrolides were not associated with an elevated risk of acute cardiac events compared to ICS. The increased risk of hearing loss in macrolide users compared to ICS users in older bronchiectasis patients should be balanced against known benefits of macrolides.

Comparison of risks of cardiac outcomes (arrhythmia and myocardial infarction), hearing loss, opportunistic infections and hip fracture between macrolide and ICS users with bronchiectasis using a robust propensity-score adjusted new-user methodologyhttps://bit.ly/3KIVp0O

Effectiveness of Beta-Lactam plus Doxycycline for Patients Hospitalized with Community-Acquired Pneumonia

BACKGROUND

Despite clinical practice guideline recommendations to use doxycycline as part of combination therapy for some patients hospitalized with pneumonia, there is minimal evidence supporting this recommendation. Our aim was to examine the association between beta-lactam plus doxycycline and mortality for patients hospitalized with community-acquired pneumonia.

METHODS

We identified patients > 65 years of age admitted to any United States Department of Veterans Affairs hospital in fiscal years 2002-2012 with a discharge diagnosis of pneumonia. We excluded those patients who did not receive antibiotic therapy concordant with the 2019 ATS/IDSA clinical practice guidelines. Using propensity score matching, we examined the association of doxycycline with 30- and 90-day mortality.

RESULTS

Our overall cohort was comprised of 70,533 patients and 5,282 (7.49%) received doxycycline. Unadjusted 30-day mortality was 6.4% for those who received a beta-lactam plus doxycycline vs. 9.1% in those who did not (p<0.0001), and 90-day mortality was 13.8% for those who received a beta-lactam + doxycycline vs. 16.8% for those who did not (p<0.0001). In the propensity score matched models, both 30- (odds ratio 0.72, 95% confidence interval, 0.63-0.84) and 90-day (0.83, 0.74-0.92) mortality were significantly lower for those who received doxycycline.

CONCLUSIONS

In this retrospective observational cohort study, we found that doxycycline use, as part of guideline-concordant antibiotic therapy, was associated with lower 30- and 90-day mortality than regimens without doxycycline. While this supports the safety and effectiveness of antibiotic regimes that include doxycycline, additional studies, especially randomized clinical trials, are needed to confirm this.

Major adverse cardiovascular event definitions used in observational analysis of administrative databases: a systematic review

Background

Major adverse cardiovascular events (MACE) are increasingly used as composite outcomes in randomized controlled trials (RCTs) and observational studies. However, it is unclear how observational studies most commonly define MACE in the literature when using administrative data.

Methods

We identified peer-reviewed articles published in MEDLINE and EMBASE between January 1, 2010 to October 9, 2020. Studies utilizing administrative data to assess the MACE composite outcome using International Classification of Diseases 9th or 10th Revision diagnosis codes were included. Reviews, abstracts, and studies not providing outcome code definitions were excluded. Data extracted included data source, timeframe, MACE components, code definitions, code positions, and outcome validation.

Results

A total of 920 articles were screened, 412 were retained for full-text review, and 58 were included. Only 8.6% (n = 5/58) matched the traditional three-point MACE RCT definition of acute myocardial infarction (AMI), stroke, or cardiovascular death. None matched four-point (+unstable angina) or five-point MACE (+unstable angina and heart failure). The most common MACE components were: AMI and stroke, 15.5% (n = 9/58); AMI, stroke, and all-cause death, 13.8% (n = 8/58); and AMI, stroke and cardiovascular death 8.6% (n = 5/58). Further, 67% (n = 39/58) did not validate outcomes or cite validation studies. Additionally, 70.7% (n = 41/58) did not report code positions of endpoints, 20.7% (n = 12/58) used the primary position, and 8.6% (n = 5/58) used any position.

Conclusions

Components of MACE endpoints and diagnostic codes used varied widely across observational studies. Variability in the MACE definitions used and information reported across observational studies prohibit the comparison, replication, and aggregation of findings. Studies should transparently report the administrative codes used and code positions, as well as utilize validated outcome definitions when possible.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01440-5.

The long-term safety of chronic azithromycin use in adult patients with cystic fibrosis, evaluating biomarkers for renal function, hepatic function and electrical properties of the heart

Background: Azithromycin maintenance therapy is widely used in cystic fibrosis (CF), but little is known about its long-term safety. We investigated whether chronic azithromycin use is safe regarding renal function, hepatic cell toxicity and QTc-interval prolongation.Methods: Adult CF patients (72 patients using azithromycin for a cumulative period of 364.8 years and 19 controls, 108.8 years) from two CF-centers in the Netherlands with azithromycin (non)-use for at least three uninterrupted years were studied retrospectively.Results: There was no difference in mean decline of estimated glomerular filtration rate (eGFR), nor in occurrence of eGFR-events. No drug-induced liver injury could be attributed to azithromycin. Of the 39 azithromycin users of whom an ECG was available, 4/39 (10.3%) had borderline and 4/39 (10.3%) prolonged QTc-intervals, with 7/8 patients using other QTc-prolonging medication. Of the control patients 1/6 (16.7%) had a borderline QTc-interval, without using other QTc-prolonging medication. No cardiac arrhythmias were observed.Conclusion: We observed no renal or hepatic toxicity, nor cardiac arrythmias during azithromycin use in CF patients for a mean study duration of more than 5 years. One should be aware of possible QTc-interval prolongation, in particular in patients using other QTc-interval prolonging medication.

Pharmacotherapy Management for COVID-19 and Cardiac Safety: A Data Mining Approach for Pharmacovigilance Evidence from the FDA Adverse Event Reporting System (FAERS)

Background

Several pharmacological agents, such as chloroquine/hydroxychloroquine, have been promoted for COVID-19 treatment or pre-exposure prophylaxis. However, no comprehensive evaluation of the safety of these possible agents is available, and is urgently needed.

Objective

The purpose of this study was to investigate the risks of cardiac adverse events associated with the possible pharmacotherapies for COVID-19, including certain antimalarial, antiviral, and antibiotic drugs.

Patients and Methods

We conduced retrospective pharmacovigilance analyses of the US Food and Drug Administration Adverse Event Reporting System database. The reporting odds ratio (ROR), a data mining algorithm commonly used in pharmacovigilance assessment, was generated to quantify the detection signal of adverse events.

Results

Among individuals without coronavirus infection from 2015 Q1 to 2020 Q1, increased risks for cardiac disorders were found for antiviral agents such as chloroquine/hydroxychloroquine (ROR: 1.68; 95% confidence interval [CI] 1.66–1.70), lopinavir/ritonavir (ROR: 1.52; 95% CI 1.39–1.66), and antibiotics such as azithromycin (ROR: 1.37; 95% CI 1.30–1.44) and ceftriaxone (ROR: 1.92; 95% CI 1.80–2.05). Increased serious cardiac adverse events, including myocardial infarction, arrhythmia, and cardiac arrest, were also reported for these drugs. Further analyses of individuals with coronavirus infections revealed that 40% of individuals receiving chloroquine/hydroxychloroquine reported serious cardiac adverse events. Two cases resulted in QT prolongations and one case resulted in cardiac arrest. Chloroquine/hydroxychloroquine and azithromycin contributed to all the QT prolongation and cardiac arrest cases.

Conclusions

The current pharmacotherapies for COVID-19 are associated with increased risks of cardiac adverse events. Variations in the cardiac safety profiles of these pharmacotherapies were also observed. Clinicians should closely monitor patients with COVID-19, especially those at high risk, using chloroquine/hydroxychloroquine and azithromycin.

Acute cardiovascular events in patients with community acquired pneumonia: results from the observational prospective FADOI-ICECAP study

Background

The burden of cardiovascular (CV) complications in patients hospitalised for community-acquired pneumonia (CAP) is still uncertain. Available studies used different designs and different criteria to define CV complications. We assessed the cumulative incidence of acute of CV complications during hospitalisation for CAP in Internal Medicine Units (IMUs).

Methods

This was a prospective study carried out in 26 IMUs, enrolling patients consecutively hospitalised for CAP. Defined CV complications were: newly diagnosed heart failure, acute coronary syndrome, new onset of supraventricular or ventricular arrhythmias, new onset hemorrhagic or ischemic stroke or transient ischemic attack. Outcome measures were: in-hospital and 30-day mortality, length of hospital stay and rate of 30-day re-hospitalisation.

Results

A total of 1266 patients were enrolled, of these 23.8% experienced at least a CV event, the majority (15.5%) represented by newly diagnosed decompensated heart failure, and 75% occurring within 3 days. Female gender, a history of CV disease, and more severe pneumonia were predictors of CV events. In-hospital (12.2% vs 4.7%, p < 0.0001) and 30-day (16.3% vs 8.9%, p = 0.0001) mortality was higher in patients with CV events, as well as the re-hospitalisation rate (13.3% vs 9.3%, p = 0.002), and mean hospital stay was 11.4 ± 6.9 vs 9.5 ± 5.6 days (p < 0.0001). The occurrence of CV events during hospitalisation significantly increased the risk of 30-day mortality (HR 1.69, 95% CI 1.14–2.51; p = 0.009).

Conclusion

Cardiovascular events are frequent in CAP, and their occurrence adversely affects outcome. A strict monitoring might be useful to intercept in-hospital CV complications for those patients with higher risk profile.

Trial registration

NCT03798457

Registered 10 January 2019 - Retrospectively registered

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05781-w.

Preventing the development of severe COVID-19 by modifying immunothrombosis

BACKGROUND

COVID-19-associated acute respiratory distress syndrome (ARDS) is associated with significant morbidity and high levels of mortality. This paper describes the processes involved in the pathophysiology of COVID-19 from the initial infection and subsequent destruction of type II alveolar epithelial cells by SARS-CoV-2 and culminating in the development of ARDS.

MAIN BODY

The activation of alveolar cells and alveolar macrophages leads to the release of large quantities of proinflammatory cytokines and chemokines and their translocation into the pulmonary vasculature. The presence of these inflammatory mediators in the vascular compartment leads to the activation of vascular endothelial cells platelets and neutrophils and the subsequent formation of platelet neutrophil complexes. These complexes in concert with activated endothelial cells interact to create a state of immunothrombosis. The consequence of immunothrombosis include hypercoagulation, accelerating inflammation, fibrin deposition, migration of neutrophil extracellular traps (NETs) producing neutrophils into the alveolar apace, activation of the NLRP3 inflammazome, increased alveolar macrophage destruction and massive tissue damage by pyroptosis and necroptosis Therapeutic combinations aimed at ameliorating immunothrombosis and preventing the development of severe COVID-19 are discussed in detail.

Short- and long-term outcomes after incident pneumonia in adults with chronic kidney disease: a time-dependent analysis from the Stockholm CREAtinine Measurement project

BACKGROUND

Little is known about the health sequelae of pneumonia in persons with chronic kidney disease (CKD).

METHODS

We studied adults with CKD in Stockholm during 2006-11, who not previously been diagnosed with lower respiratory tract infections. We used multivariable-adjusted Cox regression with pneumonia as a time-varying exposure to estimate hazard ratios (HRs) [95% confidence intervals (CIs)] for the events of death, major adverse cardiovascular events (MACEs), acute kidney injury (AKI), CKD progression or hospitalization for urinary tract infections (UTIs)/sepsis. Cataract and knee/joint replacement served as negative control outcomes.

RESULTS

We identified 71 931 adults (mean age 79 years, 59% women), of whom 8379 (12%) were diagnosed with pneumonia during follow-up; incident pneumonia was associated with 10 times higher adjusted mortality risk during the first 90 days [HR = 10.0, 95% confidence interval (CI) 9.5-10.5] and double the mortality beyond 90 days from pneumonia diagnosis (HR = 2.0; 95% CI 1.9-2.1). Incident pneumonia was similarly associated with higher adjusted risk of MACE (<90 days: HR = 12.6; 95% CI 12.0-13.3; ≥90 days: HR = 1.5; 95% CI 1.4-1.6). The adjusted risk of CKD progression and UTI/sepsis hospitalization was highest within 90 days from pneumonia but remained elevated thereafter. For AKI, the association with incident pneumonia was only seen within 90 days. Neither cataract nor knee/joint replacement was related to pneumonia.

CONCLUSIONS

Incident pneumonia was associated with increased risks of MACE, CKD progression, severe UTI/sepsis and death, with risks highest soon after pneumonia diagnosis but extending beyond 90 days. Our findings highlight the susceptibility for adverse outcomes of CKD patients following pneumonia diagnosis, and may inform clinical decisions regarding vaccination strategies.

The Weight of Evidence From Electrophysiology, Observational, and Cardiovascular End Point Studies Demonstrates the Safety of Azithromycin

Increased use of azithromycin (AZ) in treating infections associated with coronavirus disease 2019 (COVID-19) and reports of increased incidence of prolonged corrected QT (QTc) interval associated with AZ used with hydroxychloroquine prompted us to review the latest evidence in the literature, present additional analyses of human cardiovascular (CV) electrophysiology studies, and to describe sequential steps in research and development that were undertaken to characterize the benefit-risk profile of AZ. Combined QTc findings from electrocardiograms taken during oral and i.v. pharmacokinetic-pharmacodynamic studies of AZ suggest that clinically meaningful QTc prolongation is unlikely. Findings from several observational studies were heterogeneous and not as consistent as results from at least two large randomized controlled trials (RCTs). The QTc findings presented and observational data from studies with large numbers of events are not consistent with either a proarrhythmic action of AZ or an increase in frequency of CV deaths. Well-powered RCTs do not suggest a presence of increased risk of CV or sudden cardiac death after short-term or protracted periods of AZ usage, even in patients at higher risk from pre-existing coronary disease.

Azithromycin prophylaxis after lung transplantation is associated with improved overall survival

BACKGROUND

Azithromycin prophylaxis (AP) in lung transplant recipients has been shown to reduce the composite end-point of death or chronic lung allograft dysfunction (CLAD) onset but without a clear effect on overall survival. Our program began using AP in 2010. We sought to evaluate the association between AP and survival and the risk of CLAD and baseline lung allograft dysfunction (BLAD).

METHODS

We studied double lung recipients transplanted between 2004 and 2016. We defined AP as chronic use of azithromycin initiated before CLAD onset. We analyzed the association between AP and death or retransplant using Cox regression with adjustment for potential confounders. We further used Cox and logistic models to assess the relationship between AP and post-transplant CLAD onset and BLAD, respectively.

RESULTS

A total of 445 patients were included, and 344 (77%) received AP (median time from transplant: 51 days). Patients receiving AP were more likely to receive induction with interleukin-2 receptor antagonists (57% vs 35%; p < 0.001). AP was associated with improved survival (hazard ratio [HR]: 0.59; 95% confidence interval [CI]: 0.42-0.82; p = 0.0020) in our fully adjusted model, with a reduced adjusted risk of BLAD (odds ratio: 0.53; 95% CI: 0.33-0.85; p = 0.0460) but no clear reduction in the adjusted risk of CLAD (HR: 0.69; 95% CI: 0.47-1.03; p = 0.0697).

CONCLUSIONS

AP is associated with improved survival after lung transplantation, potentially through improved baseline function. These findings build on prior trial results and suggest that AP is beneficial for lung transplant recipients.

The effect of 5-day course of hydroxychloroquine and azithromycin combination on QT interval in non-ICU COVID19(+) patients

BACKGROUND

The combination of Hydroxychloroquine (HCQ) and azithromycin showed effectiveness as a treatment for COVID-19 and is being used widely all around the world. Despite that those drugs are known to cause prolonged QT interval individually there is no study assessing the impact of this combination on electrocardiography (ECG). This study aimed to assess the impact of a 5-day course of HCQ and azithromycin combination on ECG in non-ICU COVID19(+) patients.

METHODS

In this retrospective observational study, we enrolled 109 COVID19(+) patients who required non-ICU hospitalization. All patients received 5-day protocol of HCQ and azithromycin combination. On-treatment ECGs were repeated 3-6 h after the second HCQ loading dose and 48-72 h after the first dose of the combination. ECGs were assessed in terms of rhythm, PR interval, QRS duration, QT and QTc intervals. Baseline and on-treatment ECG findings were compared. Demographic characteristics, laboratory results were recorded. Daily phone call-visit or bed-side visit were performed by attending physician.

RESULTS

Of the 109 patients included in the study, the mean age was 57.3 ± 14.4 years and 48 (44%) were male. Mean baseline PR interval was 158.47 ± 25.10 ms, QRS duration was 94.00 ± 20.55 ms, QTc interval was 435.28 ± 32.78 ms, 415.67 ± 28.51, 412.07 ± 25.65 according to Bazett's, Fridericia's and Framingham Heart Study formulas respectively. ∆PR was -2.94 ± 19.93 ms (p = .55), ∆QRS duration was 5.18 ± 8.94 ms (p = .03). ∆QTc interval was 6.64 ± 9.60 ms (p = .5), 10.67 ± 9.9 ms (p = .19), 14.14 ± 9.68 ms (p = .16) according to Bazett's, Fridericia's and Framingham Heart Study formulas respectively. There were no statistically significant differences between QTc intervals. No ventricular tachycardia, ventricular fibrillation or significant conduction delay was seen during follow-up. There was no death or worsening heart function.

CONCLUSION

The 5-day course of HCQ- AZM combination did not lead to clinically significant QT prolongation and other conduction delays compared to baseline ECG in non-ICU COVID19(+) patients.

Azithromycin in COVID-19 Patients: Pharmacological Mechanism, Clinical Evidence and Prescribing Guidelines

The global COVID-19 pandemic has led to a race to find medications that can improve the prognosis of the disease. Azithromycin, in association with hydroxychloroquine or chloroquine, has been proposed as one such medication. The aim of this review is to describe the pharmacological mechanism, clinical evidence and prescribing guidelines concerning azithromycin in COVID-19 patients. There is weak evidence on the antiviral and immunomodulating effects of azithromycin, which in addition is not based on results from COVID-19 patients specifically. Therefore, this antibacterial should be considered only as empirical treatment of community-acquired pneumonia (CAP), although not all current treatment guidelines are in agreement. After the initial expectations raised by a small trial, more recent evidence has raised serious safety concerns on the use of hydroxychloroquine or chloroquine with azithromycin to treat COVID-19 patients, as all these drugs have arrhythmogenic potential. The World Health Organization has not made recommendations suggesting the use of azithromycin with hydroxychloroquine or chloroquine as treatment for COVID-19, but some national organisations have taken a different position, recommending this as first-line treatment. Several scientific societies, including the American College of Cardiology, have cautioned about the risks of this treatment in view of the lack of evidence concerning its benefits.

The Cardiovascular Effects of Treatment with Hydroxychloroquine and Azithromycin

Hydroxychloroquine combined with azithromycin has been investigated for activity against coronavirus disease 2019 (COVID-19), but concerns about adverse cardiovascular (CV) effects have been raised. This study evaluated claims data to determine if risks for CV events were increased with hydroxychloroquine alone or combined with azithromycin. We identified data from 43,752 enrollees that qualified for analysis. The number of CV events increased by 25 (95% confidence interval [CI]: 8, 42, p=0.005) per 1000 people per year of treatment with hydroxychloroquine alone compared with pretreatment levels and by 201 (95% CI: 145, 256, p<0.001) events per 1000 people per year when individuals took hydroxychloroquine and azithromycin. These rates translate to an additional 0.34 (95% CI: 0.11, 0.58) CV events per 1000 patients placed on a 5-day treatment with hydroxychloroquine monotherapy and 2.75 (95% CI: 1.99, 3.51) per 1000 patients on a 5-day treatment with both hydroxychloroquine and azithromycin. The rate of adverse events increased with age following exposure to hydroxychloroquine alone and combined with azithromycin. For females aged 60 to 79 years prescribed hydroxychloroquine, the rate of adverse CV events was 0.92 per 1000 patients on 5 days of therapy, but it increased to 4.78 per 1000 patients when azithromycin was added. The rate of adverse CV events did not differ significantly from zero for patients 60 years of age or younger. These data suggest that hydroxychloroquine with or without azithromycin is likely safe in individuals under 60 years of age if they do not have additional CV risks. However, the combination of hydroxychloroquine and azithromycin should be used with extreme caution in older patients.

Tetrodotoxin-Sensitive Neuronal-Type Na+ Channels: A Novel and Druggable Target for Prevention of Atrial Fibrillation

Background

Atrial fibrillation (AF) is a comorbidity associated with heart failure and catecholaminergic polymorphic ventricular tachycardia. Despite the Ca²⁺‐dependent nature of both of these pathologies, AF often responds to Na⁺ channel blockers. We investigated how targeting interdependent Na⁺/Ca²⁺ dysregulation might prevent focal activity and control AF.

Methods and Results

We studied AF in 2 models of Ca²⁺‐dependent disorders, a murine model of catecholaminergic polymorphic ventricular tachycardia and a canine model of chronic tachypacing‐induced heart failure. Imaging studies revealed close association of neuronal‐type Na⁺ channels (nNa_v) with ryanodine receptors and Na⁺/Ca²⁺ exchanger. Catecholamine stimulation induced cellular and in vivo atrial arrhythmias in wild‐type mice only during pharmacological augmentation of nNa_v activity. In contrast, catecholamine stimulation alone was sufficient to elicit atrial arrhythmias in catecholaminergic polymorphic ventricular tachycardia mice and failing canine atria. Importantly, these were abolished by acute nNa_v inhibition (tetrodotoxin or riluzole) implicating Na⁺/Ca²⁺ dysregulation in AF. These findings were then tested in 2 nonrandomized retrospective cohorts: an amyotrophic lateral sclerosis clinic and an academic medical center. Riluzole‐treated patients adjusted for baseline characteristics evidenced significantly lower incidence of arrhythmias including new‐onset AF, supporting the preclinical results.

Conclusions

These data suggest that nNa_Vs mediate Na⁺‐Ca²⁺ crosstalk within nanodomains containing Ca²⁺ release machinery and, thereby, contribute to AF triggers. Disruption of this mechanism by nNa_v inhibition can effectively prevent AF arising from diverse causes.

Association of Azithromycin Use With Cardiovascular Mortality

IMPORTANCE

Azithromycin is one of the most commonly prescribed antibiotics in the US. It has been associated with an increased risk of cardiovascular death in some observational studies.

OBJECTIVE

To estimate the relative and absolute risks of cardiovascular and sudden cardiac death after an outpatient azithromycin prescription compared with amoxicillin, an antibiotic not known to increase cardiovascular events.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included 2 large, diverse, community-based integrated care delivery systems with comprehensive capture of encounters and prescriptions from January 1, 1998, to December 31, 2014. The cohort included patients aged 30 to 74 years who had at least 12 months of health-plan enrollment prior to antibiotic exposure. The exclusion criteria were absence of prescription benefits, prescription for more than 1 type of study antibiotic within 10 days, hospitalization or nursing home residence, and serious medical conditions. Risk of cardiovascular death associated with azithromycin vs amoxicillin exposure was calculated after controlling for confounding factors using a propensity score. Data were analyzed from December 1, 2016, to March 30, 2020.

EXPOSURES

Outpatient prescription of azithromycin or amoxicillin.

MAIN OUTCOMES AND MEASURES

The primary outcomes were cardiovascular death and sudden cardiac death. An a priori subgroup analysis quantified the effects of azithromycin exposure among patients with increased baseline cardiovascular risk. The secondary outcomes were noncardiovascular death and all-cause mortality.

RESULTS

The study included 7 824 681 antibiotic exposures, including 1 736 976 azithromycin exposures (22.2%) and 6 087 705 amoxicillin exposures (77.8%), among 2 929 008 unique individuals (mean [SD] age, 50.7 [12.3] years; 1 810 127 [61.8%] women). Azithromycin was associated with a significantly increased hazard of cardiovascular death (hazard ratio [HR], 1.82; 95% CI, 1.23-2.67) but not sudden cardiac death (HR, 1.59; 95% CI, 0.90-2.81) within 5 days of exposure. No increases in risk were found 6 to 10 days after exposure. Similar results were observed in patients within the top decile of cardiovascular risk (HR, 1.71; 95% CI, 1.06-2.76). Azithromycin was also associated with an increased risk of noncardiovascular death (HR, 2.17; 95% CI, 1.44-3.26) and all-cause mortality (HR, 2.00; 95% CI, 1.51-2.63) within 5 days of exposure.

CONCLUSIONS AND RELEVANCE

These findings suggest that outpatient azithromycin use was associated with an increased risk of cardiovascular death and noncardiovascular death. Causality cannot be established, particularly for noncardiovascular death, owing to the likelihood of residual confounding.

Burden of Community-Acquired Pneumonia and Unmet Clinical Needs

Community-acquired pneumonia (CAP) is the leading cause of death among infectious diseases and an important health problem, having considerable implications for healthcare systems worldwide. Despite important advances in prevention through vaccines, new rapid diagnostic tests and antibiotics, CAP management still has significant drawbacks. Mortality remains very high in severely ill patients presenting with respiratory failure or shock but is also high in the elderly. Even after a CAP episode, higher risk of death remains during a long period, a risk mainly driven by inflammation and patient-related co-morbidities. CAP microbiology has been altered by new molecular diagnostic tests that have turned viruses into the most identified pathogens, notwithstanding uncertainties about the specific role of each virus in CAP pathogenesis. Pneumococcal vaccines also impacted CAP etiology and thus had changed Streptococcus pneumoniae circulating serotypes. Pathogens from specific regions should also be kept in mind when treating CAP. New antibiotics for CAP treatment were not tested in severely ill patients and focused on multidrug-resistant pathogens that are unrelated to CAP, limiting their general use and indications for intensive care unit (ICU) patients. Similarly, CAP management could be personalized through the use of adjunctive therapies that showed outcome improvements in particular patient groups. Although pneumococcal vaccination was only convincingly shown to reduce invasive pneumococcal disease, with a less significant effect in pneumococcal CAP, it remains the best therapeutic intervention to prevent bacterial CAP. Further research in CAP is needed to reduce its population impact and improve individual outcomes.

Considerations for the optimal management of antibiotic therapy in elderly patients

OBJECTIVES

To maximise efficacy and minimise toxicity, special considerations are required for antibiotic prescription in elderly patients. This review aims to provide practical suggestions for the optimal management of antibiotic therapy in elderly patients.

METHODS

This was a narrative review. A literature search of published articles in the last 15 years on antibiotics and elderly patients was performed using the Cochrane Library and PubMed electronic databases. The three priority areas were identified: (i) pharmacokinetics/pharmacodynamics (PK/PD) for optimising dosage regimens and route of administration; (ii) antibiotic dosages in some special subpopulations; and (iii) treatment considerations relating to different antibiotic classes and their adverse events.

RESULTS

Clinicians should understand the altered PK/PD of drugs in this population owing to co-morbid conditions and normal physiological changes associated with ageing. The body of evidence justifies the need for individualised dose selection, especially in patients with impaired renal and liver function. Clinicians should be aware of the major drug-drug interactions commonly observed in the elderly as well as potential side effects.

CONCLUSION

Antibiotic therapy in the elderly requires a comprehensive approach, including strategies to improve appropriate antibiotic prescribing, limit their use for uncomplicated infections and ensure the attainment of an optimal PK/PD target. To this purpose, further studies involving the elderly are needed to better understand the PK of antibiotics. Moreover, it is necessary to assess the role therapeutic drug monitoring in guiding antibiotic therapy in elderly patients in order to evaluate its impact on clinical outcome.

Community-Acquired Pneumonia. Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) Guidelines. 2020 Update

The guidelines for community-acquired pneumonia, last published in 2010, have been updated to provide recommendations based on a critical summary of the latest literature to help health professionals make the best decisions in the care of immunocompetent adult patients. The methodology was based on 6 PICO questions (on etiological studies, assessment of severity and decision to hospitalize, antibiotic treatment and duration, and pneumococcal conjugate vaccination), agreed by consensus among a working group of pulmonologists and an expert in documentation science and methodology. A comprehensive review of the literature was performed for each PICO question, and these were evaluated in in-person meetings. The American Thoracic Society guidelines were published during the preparation of this paper, so the recommendations of this association were also evaluated. We concluded that the etiological source of the infection should be investigated in hospitalized patients who have suspected resistance or who fail to respond to treatment. Prognostic scales, such as PSI, CURB 65, and CRB65, are useful for assessing severity and the decision to hospitalize. Different antibiotic regimens are indicated, depending on the treatment setting - outpatient, hospital, or intensive care unit - and the resistance of PES microorganisms should be calculated. The minimum duration of antibiotic treatment should be 5 days, based on criteria of clinical stability. Finally, we reviewed the indication of the 13-valent conjugate vaccine in immunocompetent patients with risk factors and comorbidity.

Duration and Life-Stage of Antibiotic Use and Risks of All-Cause and Cause-Specific Mortality: Prospective Cohort Study

Rationale: The overuse of antibiotics has been an important clinical issue, and antibiotic exposure is linked to alterations in gut microbiota, which has been related to risks of various chronic diseases such as cardiovascular disease and cancer. Also, duration of antibiotic exposure may be a risk factor of premature death. Objective: We investigated associations of life-stage and duration of antibiotic use during adulthood with risks of all-cause and cause-specific mortality. Methods and Results: This prospective cohort study included 37 516 women aged ≥60 years who were free of cardiovascular disease or cancer from the Nurses' Health Study. Participants reported a total amount of time they used antibiotics (none, <15 days, 15 days to <2 months, or ≥2 months) in the middle- (age, 40-59) and late adulthood (age, 60 or older). We estimated hazard ratios for all-cause mortality and deaths from cardiovascular disease or cancer over 10 years according to duration of antibiotic use. During 355 918 person-years of follow-up, we documented 4536 deaths from any cause (including 728 cardiovascular deaths and 1206 cancer deaths). As compared with women who did not use antibiotics, those who used them for ≥2 months in late adulthood had increased risks of all-cause mortality (hazard ratio, 1.16 [95% CI, 1.01-1.33]) and cardiovascular mortality (hazard ratio, 1.49 [95% CI, 1.04-2.13]), but not cancer mortality (hazard ratio, 0.85 [95% CI, 0.65-1.12]) after adjustment for chronic metabolic diseases, antibiotic use during middle adulthood, indication for use, demographic factors, and lifestyle/dietary factors. The association was more evident among women who also used antibiotics in middle-adulthood than among those who did not use during this life-stage. Conclusions: Long-term use of antibiotics in late adulthood may be a risk factor for all-cause and cardiovascular mortality. The unfavorable effect of antibiotic exposure for subsequent risks of deaths due to chronic diseases needs to be considered.

Duration and life-stage of antibiotic use and risk of cardiovascular events in women

AIMS

Growing data suggest that antibiotic exposure is associated with a long-lasting alteration in gut microbiota, and may be related to subsequent cardiovascular disease (CVD). We investigated associations of life-stage and duration of antibiotic exposure during adulthood with subsequent CVD events.

METHODS AND RESULTS

This study included 36 429 women initially free of CVD and cancer from the Nurses' Health Study. We estimated hazard ratios (HRs) for CVD (a composite endpoint of coronary heart disease or stroke) according to duration of antibiotic use in young (age 20-39), middle (age 40-59), and late (age 60 and older) adulthood. During an average of 7.6 years of follow-up, 1056 participants developed CVD. Women with long-term use of antibiotics (for ≥2 months) in late adulthood had a significantly increased risk of CVD (HR 1.32, 95% confidence interval 1.03-1.70) after adjustment for covariates (such as demographic factors, diet and lifestyle, reasons for antibiotic use, overweight or obesity, disease status, and other medication use), as compared to women who did not use antibiotics in this life-stage. Longer duration of antibiotic use in middle adulthood was also related to higher risk of CVD (P trend = 0.003) after controlling for these covariates. There was no significant relationship between the use in young adulthood and the risk of CVD.

CONCLUSION

In this study which examined the antibiotic use in different life-stages, longer duration of exposure to antibiotics in the middle and older adulthood was related to an increased risk of future CVD events among elderly women at usual risk.

Association of atypical antipsychotics and mortality for patients hospitalised with pneumonia

Introduction

Atypical antipsychotics are commonly used in patients with psychiatric conditions and dementia. They are also frequently used in patients being admitted with pneumonia; however, there are few safety data. The purpose of this study was to examine whether atypical antipsychotic use prior to admission is associated with increased mortality in patients with pneumonia.

Methods

We conducted a retrospective cohort study of hospitalised patients with pneumonia over a 10-year period. We included patients 65 years or older and hospitalised with pneumonia. For our primary analysis, we used propensity score matching to balance confounders between atypical antipsychotic users and nonusers.

Results

There were 102 897 patients and 5977 were taking atypical antipsychotics. After matching there were 5513 users and 5513 nonusers. Atypical antipsychotic use was associated with increased odds of 30-day (OR 1.20, 95% CI 1.11–1.31) and 90-day mortality (1.19, 1.09–1.30).

Conclusion

In patients 65 years or older that are hospitalised with pneumonia, we found an association between atypical antipsychotic use and increased odds of mortality. This was particularly pronounced for patients with pre-existing psychiatric or cardiac conditions. We suggest closely monitoring patients who use these medications and minimising their use in older adult patients.

When hospitalised with pneumonia, older patients who use atypical antipsychotics should be monitored closely and their use of these drugs should be minimised as much as possiblehttp://bit.ly/2JEevHV

Characteristics and Healthcare Utilization Among Veterans Treated for Heart Failure With Reduced Ejection Fraction Who Switched to Sacubitril/Valsartan

Background:

US guidelines recommend that patients with heart failure with reduced ejection fraction (HFrEF), who tolerate an ACEI (angiotensin-converting enzyme inhibitor) or ARB (angiotensin II receptor blocker), be switched to sacubitril/valsartan to reduce morbidity and mortality. We compared characteristics and healthcare utilization between Veterans with HFrEF who were switched to sacubitril/valsartan versus maintained on an ACEI or ARB.

Methods:

retrospective cohort study of treated HFrEF (July 2015–June 2017) using Veterans Affairs data. The index date was the first fill for sacubitril/valsartan and if none, for an ACEI or ARB. Treated HFrEF was defined by (1) left ventricular ejection fraction ≤40%, (2) ≥1 in/outpatient HF encounter, and (3) ≥1 ACEI or ARB fill, all within 1-year preindex. Poisson regression models were used to compare baseline characteristics and 1:1 propensity score-matched adjusted 4-month follow-up healthcare utilization between sacubitril/valsartan switchers and ACEI or ARB maintainers.

Results:

Switchers (1612; 4.2%) were less likely than maintainers (37 065; 95.8%) to have a history of myocardial infarction or hypertension, and more likely to be black, have a lower left ventricular ejection fraction, and higher preindex healthcare utilization. Switchers were less likely to experience follow-up all-cause hospitalizations (11.2% versus 14.0%; risk ratio 0.80 [95% CI, 0.65–0.98], P value 0.035).

Conclusions:

Few Veterans with treated HFrEF were switched to sacubitril/valsartan within the first 2 years of Food and Drug Administration approval. Sacubitril/valsartan use was associated with a lower risk for all-cause hospitalizations at 4 months follow-up. Reasons for lack of guideline-recommended sacubitril/valsartan initiation warrant investigation and may reveal opportunities for HFrEF care optimization.

Hot topics and current controversies in community-acquired pneumonia

Community-acquired pneumonia (CAP) is one of the most common infectious diseases, as well as a major cause of death both in developed and developing countries, and it remains a challenge for physicians around the world. Several guidelines have been published to guide clinicians in how to diagnose and take care of patients with CAP. However, there are still many areas of debate and uncertainty where research is needed to advance patient care and improve clinical outcomes. In this review we highlight current hot topics in CAP and present updated evidence around these areas of controversy.

Community-acquired pneumonia is the most frequent cause of infectious death worldwide; however, there are several areas of controversy that should be addressed to improve patient care. This review presents the available data on these topics.http://bit.ly/2ShnH7A

Antipseudomonal monotherapy or combination therapy for older adults with community-onset pneumonia and multidrug-resistant risk factors: a retrospective cohort study

BACKGROUND

Infectious Diseases Society of America guidelines recommend empiric antipseudomonal combination therapy when Pseudomonas is suspected. However, combination antipseudomonal therapy is controversial. This study compares all-cause 30-day mortality in older patients who received antipseudomonal monotherapy (PMT) or antipseudomonal combination therapy (PCT) for the treatment of community-onset pneumonia.

METHODS

This population-based, retrospective cohort study used data from over 150 Veterans Health Administration hospitals. Patients were classified as being at low, medium, or high risk of drug-resistant pathogens. In total, 31,027 patients were assigned to PCT or PMT treatment arms based on antibiotics received in the first 48 hours of hospital admission.

RESULTS

The unadjusted 30-day mortality difference between PCT and PMT was most pronounced in the low-risk group (18% vs 8%), followed by the medium-risk group (24% vs 18%) and then the high-risk group (39% vs 33%). PCT was associated with higher 30-day mortality than PMT overall (adjusted odds ratio [aOR], 1.54; 95% confidence interval [CI], 1.43-1.66) in all 3 risk groups: low (aOR, 1.69; 95% CI, 1.50-1.89), medium (aOR, 1.30; 95% CI, 1.14-1.48), and high (aOR, 1.21; 95% CI, 1.04-1.40).

CONCLUSIONS

Older adults who received combination antipseudomonal therapy for community-onset pneumonia fared worse than those who received monotherapy. Empiric combination antipseudomonal therapy should not be routinely offered to all patients suspected of having pseudomonal pneumonia.

Treating bacterial pneumonia in people living with HIV

Introduction: Bacterial pneumonia remains an important cause of morbidity and mortality in people living with HIV (PLWH) in the antiretroviral therapy (ART) era. In addition to being immunocompromised, as reflected by low CD4 cell counts and elevated HIV viral loads, PLWH often have other behaviors associated with an increased risk of pneumonia including smoking and injected drug use. As PLWH are aging, comorbid conditions such as chronic obstructive pulmonary disease (COPD), cancers, and cardiovascular, renal and liver diseases are emerging as additional risk factors for pneumonia. Pathogens are often similar to those in HIV-uninfected individuals; however, PLWH are at risk for unusual and/or multi-drug resistant organisms causing bacterial pneumonia based, in part, on their CD4 cell counts and other exposures. Areas covered: In this review, we focus on the recognition and management of bacterial community-acquired pneumonia (CAP) in PLWH. Along with antimicrobial treatment, we discuss prevention strategies such as vaccination and smoking cessation. Expert opinion: Early initiation of ART after HIV infection can decrease the risk of pneumonia. Improved efforts at vaccination, smoking cessation, and reduction of other substance use are urgently needed in PLWH to decrease the risk for bacterial pneumonia. As PLWH are aging, comorbidities are additional risk factors for bacterial CAP.

Impact of Cirrhosis on Pneumonia-Related Outcomes in Hospitalized Older Veterans

BACKGROUND

Prior research has demonstrated high mortality rates in patients with cirrhosis who contract bacterial infections. The purpose of our study was to explore clinical outcomes such as 90-day mortality, rehospitalization, and intensive care unit (ICU) admission in older veterans with pneumonia and cirrhosis.

METHODS

We conducted a retrospective cohort study of hospitalized patients with community-acquired pneumonia at any Departments of Veterans Affairs (VA) hospital over a 10-year period. We included patients 65 years or older who consistently received VA care and who were diagnosed with community-acquired pneumonia. There were 103,997 patients who met the inclusion criteria, and 1,246 patients with cirrhosis. We used multilevel regression models to examine the association between cirrhosis and the outcomes of interest after controlling for potential confounders.

RESULTS

Cirrhosis was associated with significantly increased odds of 90-day mortality (odds ratio 1.79, 95% confidence interval, 1.57-2.04). There were also significantly increased odds of rehospitalization within 90-days (1.30, 1.16-1.47). No significant association was found with ICU admission (1.00, 0.83-1.19).

CONCLUSIONS

We found an association between cirrhosis and 90-day mortality and rehospitalization in older patients with pneumonia. We suggest that physicians should carefully monitor patients with cirrhosis who develop pneumonia.

Cardiac events after macrolides or fluoroquinolones in patients hospitalized for community-acquired pneumonia: post-hoc analysis of a cluster-randomized trial

Background

Guidelines recommend macrolides and fluoroquinolones in patients hospitalized with community-acquired pneumonia (CAP), but their use has been associated with cardiac events. We quantified associations between macrolide and fluoroquinolone use and cardiac events in patients hospitalized with CAP in non-ICU wards.

Methods

This was a post-hoc analysis of a cluster-randomized trial as a cohort study; including patients with a working diagnosis of CAP admitted to non-ICU wards without a cardiac event on admission. We calculated cause-specific hazard ratio’s (HR’s) for effects of time-dependent macrolide and fluoroquinolone exposure as compared to beta-lactam monotherapy on cardiac events, defined as new or worsening heart failure, arrhythmia, or myocardial ischemia during hospitalization.

Results

Cardiac events occurred in 146 (6.9%) of 2107 patients, including heart failure (n = 101, 4.8%), arrhythmia (n = 53, 2.5%), and myocardial ischemia (n = 14, 0.7%). These occurred in 11 of 207 (5.3%), 18 of 250 (7.2%), and 31 of 277 (11.2%) patients exposed to azithromycin, clarithromycin, and erythromycin for at least one day, and in 9 of 234 (3.8%), 5 of 194 (2.6%), and 23 of 566 (4.1%) exposed to ciprofloxacin, levofloxacin, and moxifloxacin, respectively. HR’s for erythromycin, compared to beta-lactam monotherapy, on any cardiac event and heart failure were 1.60 (95% CI 1.09;2.36) and 1.89 (95% CI 1.22;2.91), respectively. HR’s for levofloxacin and moxifloxacin, compared to beta-lactam monotherapy, on any cardiac event were 0.40 (95% CI 0.18;0.87)and 0.56 (95% CI 0.36;0.87), respectively. Findings remained consistent after adjustment for confounders and/or in a sensitivity analysis of radiologically confirmed CAP (n = 1604, 76.1%).

Conclusions

Among patients with CAP hospitalized to non-ICU wards, erythromycin use was associated with a 68% increased risk of hospital-acquired cardiac events, mainly heart failure. Levofloxacin and moxifloxacin were associated with a lower risk of heart failure. Although our study does not fully exclude confounding bias, findings remained largely unchanged in crude, adjusted, and sensitivity analyses. These findings may caution the use of erythromycin as empirical therapy in these patients.

Trial registration

The original trial was retrospectively registered under ClinicalTrials.gov Identifier NCT01660204 on August 8th, 2012.

Clinical and Economic Outcomes of Ranolazine Versus Conventional Antianginals Users Among Veterans With Chronic Stable Angina Pectoris

Real-world outcomes in patients with chronic stable angina treated with ranolazine and other antianginal medications as second- or third-line therapy are limited. In a historical cohort study of veterans with chronic stable angina, we compared time with coronary revascularization procedures, hospitalizations, and 1-year healthcare costs between new-users of ranolazine versus conventional antianginals (i.e., calcium channel blockers, β blockers, or long-acting nitrates) as second- or third-line. Weighted regression models calculated adjusted hazard ratios (HR) at up to 8-year follow-up, and adjusted incremental costs in the first year. Weighted groups comprised 4,699 ranolazine users and 31,815 conventional antianginal users. Percutaneous coronary intervention (PCI) occurred more often in ranolazine users compared with conventional antianginal users (HR 1.16; 95% confidence intervals [CI] 1.08 to 1.25, p <0.001), and coronary artery bypass grafting occurred less often (HR 0.82; 95% CI 0.68 to 1.00, p <0.046). All-cause and atrial fibrillation (AF) hospitalizations were less common with ranolazine users compared with conventional users (all-cause: HR 0.94; 95% CI 0.90 to 0.99, p <0.010; AF:HR 0.74; 95% CI 0.67 to 0.82, p <0.001), and acute coronary syndrome was more common (HR 1.13; 95% CI 1.00 to 1.27, p <0.042). Adjusted 1-year costs were $24,517 in ranolazine users and $24,798 in conventional users (difference, $-280; 95% CI $-1,742 to $1,181, p = 0.71). In conclusion, ranolazine users had lower rates of coronary artery bypass grafting and all-cause and AF hospitalizations, but higher rates of percutaneous coronary intervention and hospitalizations due to acute coronary syndrome compared with conventional antianginal users. Healthcare costs were similar between ranolazine and conventional antianginal users.

Electrocardiographic Effects of a Supratherapeutic Dose of WCK 2349, a Benzoquinolizine Fluoroquinolone

The purpose of this study was to measure the electrocardiographic (ECG) effects of WCK 2349 (the L‐alanine ester prodrug of levonadifloxacin) at a supratherapeutic oral dose of 2,600 mg. A total of 48 healthy volunteers were randomized to treatment with placebo, WCK 2349, or oral moxifloxacin, 400 mg, in a crossover‐designed thorough QT study. A supratherapeutic mean maximum levonadifloxacin concentration (C_max) of 43.3 μg/mL was achieved at 3.1 hours. A therapeutic dose of 1,000 mg b.i.d. in a previous study in patients resulted in a C_max of 17.8 μg/mL. WCK 2349 exerted no significant effect on baseline‐ and placebo‐corrected QTcF (QT interval corrected for heart rate (HR) by the Fridericia formula), QRS, or PR interval. HR was transiently accelerated by a maximum of 14.4 (95% confidence interval, 11.80–16.92) beats per minute (bpm) at 3 hours. Concentration–effect modeling predicted a mean increase of 8.0 bpm at C_max at the standard therapeutic dose. A therapeutic dose of 1,000 mg b.i.d. of WCK 2349 is not expected to cause clinically significant ECG effects, except for a possible transient increase in HR, which seems to be clinically insignificant.