Treatment failure rates and health care utilization and costs among patients with community-acquired pneumonia treated with levofloxacin or macrolides in an outpatient setting: A retrospective claims database analysis

Macrolide Treatment Failure due to Drug–Drug Interactions: Real-World Evidence to Evaluate a Pharmacological Hypothesis

Macrolide antibiotics have received criticism concerning their use and risk of treatment failure. Nevertheless, they are an important class of antibiotics and are frequently used in clinical practice for treating a variety of infections. This study sought to utilize pharmacoepidemiology methods and pharmacology principles to estimate the risk of macrolide treatment failure and quantify the influence of their pharmacokinetics on the risk of treatment failure, using clinically reported drug–drug interaction data. Using a large, commercial claims database (2006–2015), inclusion and exclusion criteria were applied to create a cohort of patients who received a macrolide for three common acute infections. Furthermore, an additional analysis examining only bacterial pneumonia events treated with macrolides was conducted. These criteria were formulated specifically to ensure treatment failure would not be expected nor influenced by intrinsic or extrinsic factors. Treatment failure rates were 6% within the common acute infections and 8% in the bacterial pneumonia populations. Regression results indicated that macrolide AUC changes greater than 50% had a significant effect on treatment failure risk, particularly for azithromycin. In fact, our results show that decreased or increased exposure change can influence failure risk, by 35% or 12%, respectively, for the acute infection scenarios. The bacterial pneumonia results were less significant with respect to the regression analyses. This integration of pharmacoepidemiology and clinical pharmacology provides a framework for utilizing real-world data to provide insight into pharmacokinetic mechanisms and support future study development related to antibiotic treatments.

Use of antibiotics and factors associated with treatment failure among 152,245 patients with pneumonia treated in the community - a retrospective cohort study

This study aims to evaluate risk factors associated with treatment failure and the antibiotics prescribed by primary care physicians in a large patient cohort treated for pneumonia in the community. A retrospective cohort study based on the databases of Maccabi Healthcare Services that provide healthcare to a quarter of the Israeli population. Included patients were > 12 years and diagnosed with pneumonia in the outpatient setting. Cohort 1 included patients with community-acquired pneumonia (CAP), whereas cohort 2 included patients with a documented pneumonia diagnosis following hospital discharge. Treatment failure (TF) was defined as either the use of a second line antibiotic OR hospital admission within 3-14 days OR death within 30 days of diagnosis. Risk factors for TF in the study cohorts were analyzed using multivariable logistic regression. During the study period, 148,376 patients were included in cohort 1 and 3,869 patients in cohort 2, with mean ages of 46.5 ± 20.3 and 63.8 ± 19.5 years, respectively. The most commonly used antibiotics were cephalosporins (36%) and macrolides (35.5%). TF occurred in 12% of cohort 1 and was associated with older age, comorbid conditions, use of non-respiratory fluoroquinolones, and penicillin. Atypical coverage (either macrolides or tetracyclines) was associated with a lower risk of failure. Among cohort 2, TF was higher (16.4%, p < 0.001) and was associated with older age, prior cancer, and congestive heart failure. Treatment failure was associated with comorbid conditions and increasing age. Among young patients with CAP and no comorbid conditions, macrolides or tetracyclines may suffice.

[Management of Adult Community-Acquired Pneumonia and Prevention - Update 2021 - Guideline of the German Respiratory Society (DGP), the Paul-Ehrlich-Society for Chemotherapy (PEG), the German Society for Infectious Diseases (DGI), the German Society of Medical Intensive Care and Emergency Medicine (DGIIN), the German Viological Society (DGV), the Competence Network CAPNETZ, the German College of General Practitioneers and Family Physicians (DEGAM), the German Society for Geriatric Medicine (DGG), the German Palliative Society (DGP), the Austrian Society of Pneumology Society (ÖGP), the Austrian Society for Infectious and Tropical Diseases (ÖGIT), the Swiss Respiratory Society (SGP) and the Swiss Society for Infectious Diseases Society (SSI)]

The present guideline provides a new and updated concept of the management of adult patients with community-acquired pneumonia. It replaces the previous guideline dating from 2016.The guideline was worked out and agreed on following the standards of methodology of a S3-guideline. This includes a systematic literature search and grading, a structured discussion of recommendations supported by the literature as well as the declaration and assessment of potential conflicts of interests.The guideline has a focus on specific clinical circumstances, an update on severity assessment, and includes recommendations for an individualized selection of antimicrobial treatment.The recommendations aim at the same time at a structured assessment of risk for adverse outcome as well as an early determination of treatment goals in order to reduce mortality in patients with curative treatment goal and to provide palliation for patients with treatment restrictions.

The Role of Delafloxacin in Patients with Community-Acquired Bacterial Pneumonia in the Outpatient Setting: A Budget Impact Model

Background and Objective

Community-acquired bacterial pneumonia (CABP) affects millions of people each year in the USA. The majority of patients with CABP are treated in the community setting with empirical antimicrobial therapy. Delafloxacin is an anionic fluoroquinolone approved for the treatment of adult patients with CABP. This de novo analysis sought to estimate the budget impact of delafloxacin in the treatment of adult patients with CABP in the outpatient setting from the payer’s perspective.

Methods

A budget impact model (BIM) was developed from the perspective of a US third-party payer to estimate the cost of introducing delafloxacin for the outpatient treatment of CABP over a 1-year time horizon. Population, clinical, and cost inputs were based on the available literature, clinical trial data, and real-world evidence studies. Scenario analyses were conducted to evaluate the potential budget impact among COPD/asthma patients based on the findings from the phase III trial of delafloxacin for CABP, which indicated that patients with COPD or asthma may experience improved effectiveness with delafloxacin compared to moxifloxacin.

Results

In the base-case analysis, with a hypothetical plan of 1,000,000 members, the model estimated that adding delafloxacin to the formulary resulted in a total budget impact of $58,987. This increase was mainly attributed to treatment acquisition costs. In the scenario analysis that was restricted to COPD/asthma patients, adding delafloxacin to the formulary was estimated to result in a total budget impact of $5,042.

Conclusion

The results of the budget impact analyses provide conservative estimates of the impact of adding delafloxacin to outpatient formularies in substitution of moxifloxacin.

Electronic supplementary material

The online version of this article (10.1007/s40261-020-00938-y) contains supplementary material, which is available to authorized users.

Antibiotic Treatment Failure and Associated Outcomes Among Adult Patients With Community-Acquired Pneumonia in the Outpatient Setting: A Real-world US Insurance Claims Database Study

Background

Antibiotic treatment failure is common among patients with community-acquired pneumonia (CAP) who are managed in the outpatient setting and is associated with higher mortality and increased health care costs. This study's objectives were to quantify the occurrence of antibiotic treatment failure (ATF) and to evaluate clinical and economic outcomes between CAP patients who experienced ATF relative to those who did not.

Methods

Retrospective analysis of the MarketScan Commercial & Medicare Supplemental Databases was performed, identifying patients ≥18 years old, with a pneumonia diagnosis in the outpatient setting, and who received a fluoroquinolone, macrolides, beta-lactam, or tetracycline. ATF was defined as any of the following events within 30 days of initial antibiotic: antibiotic refill, antibiotic switch, emergency room visit, or hospitalization. Outcomes included 30-day all-cause mortality and CAP-related health care costs.

Results

During the study period, 251 947 unique patients met inclusion criteria. The mean age was 52.2 years, and 47.7% were male. The majority of patients received a fluoroquinolone (44.4%) or macrolide (43.6%). Overall, 22.1% were classified as ATFs. Among 18-64-year-old patients, 21.2% experienced treatment failure, compared with 25.7% in those >65 years old. All-cause mortality was greater in the antibiotic failure group relative to the non-antibiotic failure group (18.1% vs 4.6%, respectively), and the differences in 30-day mortality between antibiotic failure groups increased as a function of age. Mean 30-day CAP-related health care costs were also higher in the patients who experienced treatment failure relative to those who did not ($2140 vs $54, respectively).

Conclusions

Treatment failure and poor outcomes from outpatient CAP are common with current guideline-concordant CAP therapies. Improvements in clinical management programs and therapeutic options are needed.

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

The burden of community-acquired bacterial pneumonia in the era of antibiotic resistance

INTRODUCTION

Community-acquired pneumonia (CAP) is a significant global health problem and leading cause of death and hospitalization in both the US and abroad. Increasing macrolide resistance among Streptococcus pneumoniae and other pathogens results in a greater disease burden, along with changing demographics and a higher preponderance of comorbid conditions. Areas covered: This review summarizes current data on the clinical and economic burden of CAP, with particular focus on community-acquired bacterial pneumonia (CABP). Incidence, morbidity and mortality, and healthcare costs for the US and other regions of the world are among the topics covered. Major factors that are believed to be contributing to the increased impact of CABP, including antimicrobial resistance, the aging population, and the incidence of comorbidities are discussed, as well as unmet needs in current CABP management. Expert commentary: The clinical and economic burden of CABP is staggering, far-reaching, and expected to increase in the future as new antibiotic resistance mechanisms emerge and the world's population ages. Important measures must be initiated to stabilize and potentially decrease this burden. Urgent needs in CABP management include the development of new antimicrobials, adjuvant therapies, and rapid diagnostics.

Comparative Outcome Analysis of Penicillin-Based Versus Fluoroquinolone-Based Antibiotic Therapy for Community-Acquired Pneumonia: A Nationwide Population-Based Cohort Study

Community-acquired pneumonia (CAP) is a common but potentially life-threatening condition, but limited information exists on the effectiveness of fluoroquinolones compared to β-lactams in outpatient settings. We aimed to compare the effectiveness and outcomes of penicillins versus respiratory fluoroquinolones for CAP at outpatient clinics.This was a claim-based retrospective cohort study. Patients aged 20 years or older with at least 1 new pneumonia treatment episode were included, and the index penicillin or respiratory fluoroquinolone therapies for a pneumonia episode were at least 5 days in duration. The 2 groups were matched by propensity scores. Cox proportional hazard models were used to compare the rates of hospitalizations/emergence service visits and 30-day mortality. A logistic model was used to compare the likelihood of treatment failure between the 2 groups.After propensity score matching, 2622 matched pairs were included in the final model. The likelihood of treatment failure of fluoroquinolone-based therapy was lower than that of penicillin-based therapy (adjusted odds ratio [AOR], 0.88; 95% confidence interval [95%CI], 0.77-0.99), but no differences were found in hospitalization/emergence service (ES) visits (adjusted hazard ratio [HR], 1.27; 95% CI, 0.92-1.74) and 30-day mortality (adjusted HR, 0.69; 95% CI, 0.30-1.62) between the 2 groups.The likelihood of treatment failure of fluoroquinolone-based therapy was lower than that of penicillin-based therapy for CAP on an outpatient clinic basis. However, this effect may be marginal. Further investigation into the comparative effectiveness of these 2 treatment options is warranted.

Comparative Treatment Failure Rates of Respiratory Fluoroquinolones or β-Lactam + Macrolide Versus β-Lactam Alone in the Treatment for Community-Acquired Pneumonia in Adult Outpatients: An Analysis of a Nationally Representative Claims Database

No comparative effectiveness study has been conducted for the following 3 antibiotics: respiratory fluoroquinolones, β-lactam, and β-lactam + advanced macrolide. To gain insights into the real-world clinical effectiveness of these antibiotics for community-acquired pneumonia in adult outpatients, our study investigated the treatment failure rates in 2 million representative participants from the National Health Informatics Project (NHIP) of Taiwan. A new-user cohort design was used to follow NHIP participants from January 2000 until December 2009. Treatment failure was defined by either one of the following events: a second antibiotic prescription, hospitalization due to CAP, an emergency department visit with a diagnosis of CAP, or 30-day nonaccident-related mortality. From 2006 to 2009, we identified 9256 newly diagnosed CAP outpatients, 1602 of whom were prescribed levofloxacin, 2100 were prescribed moxifloxacin, 5049 were prescribed β-lactam alone, and 505 were prescribed advanced macrolide + β-lactam. Compared with the β-lactam-based regimen, the propensity score-matched odds ratio for composite treatment failure was 0.81 (95% CI, 0.67-0.97) for moxifloxacin, 1.10 (95% CI, 0.90-1.35) for levofloxacin, and 0.95 (95% CI, 0.67-1.35) for macrolide +β-lactam. Moxifloxacin was associated with lower treatment failure rates compared with β-lactam alone, or levofloxacin in Taiwanese CAP outpatients. However, due to inherent limitations in our claims database, more randomized controlled trials are required before coming to a conclusion on which antibiotic is more effective for Taiwanese CAP outpatients. More population-based comparative effectiveness studies are also encouraged and should be considered as an integral piece of evidence in local CAP treatment guidelines.

What Is New in Antibiotic Therapy in Community-Acquired Pneumonia? An Evidence-Based Approach Focusing on Combined Therapy

Despite all published literature, controversies remain about the optimal antibiotic treatment in community-acquired pneumonia. The most debated issue is whether it is necessary to empirically start one or two antibiotics, i.e. whether or not to cover atypical agents. A review of the literature published from 2005 to present was completed, searching for new insights in antibiotic treatment in community-acquired pneumonia (CAP) focusing on monotherapy versus combined therapy. Forty-one articles were identified enrolling outpatients, and patients admitted to the ward and to the intensive care unit: 11 were meta-analyses, 8 clinical trials and 22 observational-prospective and retrospective-studies. Although controversies remain in the treatment of CAP, the use of combination therapy seems to be associated with a lower mortality in case of severe CAP that requires intensive care unit (ICU) admission, especially when a beta-lactam-macrolide association is delivered. Moreover, combination therapy is associated with better outcomes-although not always with a lower mortality-in cases of non-ICU patients with risk factors for a poor outcome, bacteraemic pneumococcal pneumonia and high suspicion of infection by atypical agents. In this setting, it appears that the best choice of treatment may be a beta-lactam-macrolide regimen.

Treatment of Community-Acquired Pneumonia in Adults: Analysis of the National Dispensing Database

Crude national ambulatory antibiotic dispensing data (2007-2011) of adult patients (aged between 20 and below 65 years) with CAP were obtained and expressed as DDD per 1000 inhabitants and per day (DID). European quality indicators of antibiotic prescribing were calculated and adherence rate to the national CAP guideline was assessed. Antibiotic use for CAP in adults ranged between 0.27 and 0.30 DID in various years. The most frequently used antibacterials were levofloxacin, co-amoxiclav and clarithromycin. Antibiotic use in CAP was compliant with the European recommendations in 6.4% in 2007, which decreased to 4.9% by 2011, in contrast to the optimal compliant range of 80-100%. The consumption of fluoroquinolones mounted up to ~40% in both genders, which exceeded the recommended range (0-5%) substantially. National guideline also favoured the use of macrolides in the empiric therapy of CAP in otherwise healthy adults; hence, guideline-concordant antibiotic use ranged between 24.0-32.3%. Agents that were contra-indicated in the empiric therapy of CAP were also used in 6.5-9.0% in various years. These data reflect some worrisome figures and trends in the outpatient antibiotic treatment of adults with CAP. Clarified and updated national guidelines focusing on outpatients and incentives/regulations to increase guideline concordance are warranted.

Association between antibiotic prescribing in pregnancy and cerebral palsy or epilepsy in children born at term: a cohort study using the health improvement network

BACKGROUND

Between 19%-44% pregnant women are prescribed antibiotics during pregnancy. A single, large randomised-controlled-trial (ORACLE Childhood Study II) found an increased risk of childhood cerebral palsy and possibly epilepsy following prophylactic antibiotic use in pregnant women with spontaneous preterm labour. We ascertained whether this outcome could be reproduced across the population of babies delivered at term and prospectively followed in primary-care using data from The Health Improvement Network.

METHODS

We determined the risk of cerebral palsy or epilepsy in children whose mothers were prescribed antibiotics during pregnancy using a cohort of 195,909 women linked to their live, term-born, singleton children. We compared the effect of antibiotic class, number of courses and timing of prescribing in pregnancy. Analyses were adjusted for maternal risk factors (e.g. recorded infection, age, chronic conditions, social deprivation, smoking status). Children were followed until age seven years or cessation of registration with the primary-care practitioner.

RESULTS

In total, 64,623 (33.0%) women were prescribed antibiotics in pregnancy and 1,170 (0.60%) children had records indicating cerebral palsy or epilepsy. Adjusted analyses showed no association between prescribing of any antibiotic and cerebral palsy or epilepsy (adj.HR 1.04, 95%CI 0.91-1.19). However, compared with penicillins, macrolides were associated with an increased risk of cerebral palsy or epilepsy (adj.HR 1.78, 95%CI 1.18-2.69; number needed to harm 153, 95%CI 71-671).

CONCLUSIONS

We found no overall association between antibiotic prescribing in pregnancy and cerebral palsy and/or epilepsy in childhood. However, our finding of an increased risk of cerebral palsy or epilepsy associated with macrolide prescribing in pregnancy adds to evidence that macrolide use is associated with serious harm.

The association of antibiotic treatment regimen and hospital mortality in patients hospitalized with Legionella pneumonia

BACKGROUND

Guidelines recommend azithromycin or a quinolone antibiotic for treatment of Legionella pneumonia. No clinical study has compared these strategies.

METHODS

We performed a retrospective cohort analysis of adults hospitalized in the United States with a diagnosis of Legionella pneumonia in the Premier Perspectives database (1 July 2008-30 June 2013). Our primary outcome was hospital mortality; we additionally evaluated hospital length of stay, development of Clostridium difficile colitis, and total hospital cost. We used propensity-based matching to compare patients treated with azithromycin vs a quinolone. All analyses were repeated on a subgroup of more severely ill patients, defined as requiring intensive care unit admission or mechanical ventilation or having a predicted probability of hospital mortality in the top quartile for all patients.

RESULTS

Legionella pneumonia was diagnosed in 3152 adults across 437 hospitals. Quinolones alone were used in 28.8%, azithromycin alone was used in 34.0%, and 1.8% received both. Crude hospital mortality was similar: 6.6% (95% confidence interval [CI], 5.0%-8.2%) for quinolones vs 6.4% (95% CI, 5.0%-7.9%) for azithromycin (P = .87); after propensity matching (n = 813 in each group), mortality remained similar (6.3% [95% CI, 4.6%-7.9%] vs 6.5% [95% CI, 4.8%-8.2%], P = .84 for the whole cohort, and 14.9% [95% CI, 10.0%-19.8%] vs 18.3% [95% CI, 13.0%-23.6%], P = .36 for the more severely ill). There was no difference in hospital length of stay, development of C. difficile, or total hospital cost.

CONCLUSIONS

Use of azithromycin alone or a quinolone alone for treatment of Legionella pneumonia was associated with similar hospital mortality. Few patients receive combination therapy.

What is the best approach to the nonresponding patient with community-acquired pneumonia?

Treatment failure in community-acquired pneumonia (CAP) is the failure to normalize the clinical features (eg, fever, cough, sputum production), or nonresolving image in chest radiograph, despite antimicrobial therapy. The incidence of treatment failure in CAP has not been clearly established; according to several studies it ranges between 6% and 15%. The rate of mortality increases significantly, especially in those patients with severe CAP. It is important to be able to identify what patients are at risk for progressive or treatment failure pneumonia that may make them candidates for a more careful monitoring.

[Multidisciplinary guidelines for the management of community-acquired pneumonia]

Community-acquired pneumonia (CAP) is an infectious respiratory disease with an incidence that ranges from 3 to 8 cases per 1,000 inhabitants per year. This incidence increases with age and comorbidities. Forty per cent of CAP patients require hospitalization and around 10% of these patients are admitted in an Intensive Care Unit (ICU). Several studies have suggested that the implementation of clinical guidelines has a positive impact in the outcome of patients including mortality and length of stay. The more recent and used guidelines are those from Infectious Diseases Society of America/American Thoracic Society, published in 2007, the 2009 from the British Thoracic Society, and that from the European Respiratory Society/European Society of Clinical Microbiology and Infectious Diseases, published in 2010. In Spain, the most recently released guideline is the Sociedad Española de Neumología y Cirugía Torácica-2011 guideline. The present guidelines GNAC are designed to be used by the majority of health-care professionals that can participate in the care of CAP patients including diagnosis, decision of hospital and ICU admission, treatment and prevention. The Centro Cochrane Iberoamericano (CCIB) has participated in summarizing the previous guidelines and in the bibliography search. For each one of the following sections the panel of experts has developed a table with recommendations classified according to its evidence, strength and practical applicability using the Grading of Recommendations of Assessment Development and Evaluations (GRADE) system: 1. Epidemiology, microbiological etiology and antibiotic resistances.2. Clinical and microbiological diagnosis.3. Prognostic scales and decision of hospital admission.4. ICU admission criteria. 5. Empirical and definitive antibiotic treatment.6. Treatment failure. 7. Prevention.

Population-based cohort study of outpatients with pneumonia: rationale, design and baseline characteristics

Background

The vast majority of research in the area of community-acquired pneumonia (CAP) has been based on patients admitted to hospital. And yet, the majority of patients with CAP are treated on an ambulatory basis as outpatients, either by primary care physicians or in Emergency Departments. Few studies have been conducted in outpatients with pneumonia, and there is a paucity of data on short and long term morbidity or mortality and associated clinical correlates in this group of patients.

Methods

From 2000–2002, all CAP patients presenting to 7 Emergency Departments in Edmonton, Alberta, Canada were prospectively enrolled in a population-based registry. Clinical data, including pneumonia severity index (PSI) were collected at time of presentation. Patients discharged to the community were then followed for up to 5 years through linkage to the provincial administrative databases. The current report provides the rationale and design for the cohort, as well as describes baseline characteristics and 30-day morbidity and mortality.

Results

The total sample included 3874 patients. After excluding patients who were hospitalized, died or returned to the Emergency Department the same day they were initially discharged (n = 451; 12 %), and patients who could not be linked to provincial administrative databases (n = 237; 6 %), the final cohort included 3186 patients treated according to a validated clinical management pathway and discharged back to the community. Mean age was 51 (SD = 20) years, 53 % male; 4 % resided in a nursing home, 95 % were independently mobile, and 88 % had mild (PSI class I-III) pneumonia. Within 30-days, return to Emergency Department was common (25 %) as was hospitalization (8 %) and 1 % of patients had died.

Conclusions

To our knowledge, this represents the largest clinically-detailed outpatient CAP cohort assembled to date and will add to our understanding of the determinants and outcomes in this under-researched patient population. The rich clinical data along with the long term health care utilization and mortality will allow for the identification of novel prognostic indicators. Given how under studied this population is, the findings should aid clinicians in the routine care of their outpatients with pneumonia and help define the next generation of research questions.

Macrolides vs. quinolones for community-acquired pneumonia: meta-analysis of randomized controlled trials

The relative efficacy, safety and ecological implications of macrolides vs. quinolones in the treatment of community-acquired pneumonia (CAP) are debatable. We performed a systematic review and meta-analysis of randomized controlled trials comparing any macrolide vs. any quinolone for the treatment of CAP among adult inpatients or outpatients, as monotherapy or both in combination with a beta-lactam. We did not limit inclusion by pneumonia severity, publication status, language or date of publication. The primary outcomes assessed were 30-day all-cause mortality and treatment failure. Two authors independently extracted the data. Fixed effect meta-analysis of risk ratios (RRs) with 95% confidence intervals was performed. Sixteen trials (4989 patients) fulfilling inclusion criteria were identified, mostly assessing outpatients with mild to moderate CAP. All-cause mortality was not significantly different for macrolides vs. quinolones, RR 1.03 (0.63-1.68, seven trials), with a low event rate (2%). Treatment failure was significantly lower with quinolones, RR 0.78 (0.67-0.91, 16 trials). The definition of failure used in the primary studies was not clearly representative of patients' benefit. Microbiological failure was lower with quinolones, RR 0.63 (0.49-0.81, 13 trials). All adverse events, adverse events requiring discontinuation and any premature antibiotic discontinuation were significantly more frequent with macrolides, mainly on account of gastrointestinal adverse events. Resistance development was not assessed in the trials. Randomized controlled trials show an advantage of quinolones in the treatment of CAP with regard to clinical cure without need for antibiotic modification at end of treatment and gastrointestinal adverse events. The clinical significance of this advantage is unclear.

Guideline adherence and macrolides reduced mortality in outpatients with pneumonia

BACKGROUND

For outpatients with pneumonia, guidelines recommend empiric antibiotics and some suggest macrolides are preferred agents. We hypothesized that both guideline-concordant antibiotics and macrolides would be associated with reduced mortality.

METHODS

All outpatients with pneumonia assessed at 7 Emergency Departments in Edmonton, Alberta, Canada were enrolled in a population-based registry that included clinical-radiographic data, Pneumonia Severity Index (PSI) and treatments. Guideline-concordant regimens included macrolides and respiratory fluoroquinolones; other regimens were "discordant". Main outcome was 30-day all-cause mortality.

RESULTS

The study included 2973 outpatients; mean age 51 years, 47% female, most had mild pneumonia (73% PSI Class I-II). Over 30-days, 38 (1%) patients died, 228 (8%) were hospitalized, and 253 (9%) reached the endpoint of death or hospitalization. Most (2845 [96%]) patients received guideline-concordant antibiotics. Compared to patients receiving discordant antibiotics, those receiving guideline-concordant antibiotics were less likely to die within 30-days (8 [6%] versus 30 [1%], adjusted OR 0.23, 95% CI 0.09-0.59, p = 0.002). Within the guideline-concordant subgroup, compared to the 947 (33%) patients treated with fluoroquinolones, those receiving macrolides [1847 (64%)] were less likely to die (25 [3%] versus 4 [0.2%], adjusted OR 0.28, 95% CI 0.09-0.86, p = 0.03).

CONCLUSIONS

In outpatients with pneumonia, treatment with guideline-concordant antibiotics and macrolides were both associated with mortality reduction.

Fluoroquinolones in the management of community-acquired pneumonia in primary care

A literature search was conducted to evaluate the pharmacokinetic and pharmacodynamic profile of the respiratory fluoroquinolones (gemifloxacin, levofloxacin and moxifloxacin) and their efficacy and safety in the management of community-acquired pneumonia (CAP). Data show that CAP is a common presentation in primary care practice, and is associated with high rates of morbidity and mortality, particularly in the elderly. Although the causative pathogens differ depending on treatment setting and patient factors, Streptococcus pneumoniae is the primary pathogen in all treatment settings. As a class, the respiratory fluoroquinolones have a very favorable pharmacokinetic and pharmacodynamic profile. Pharmacodynamic criteria suggest that moxifloxacin and gemifloxacin are more potent against S. pneumoniae, which may have the added benefit of reducing resistance selection and enhancing bacterial eradication. The respiratory fluoroquinolones are also generally well tolerated, and are first-line options for outpatient treatment of CAP in patients with comorbidities or previous antibiotic use.

Comparative antibiotic failure rates in the treatment of community-acquired pneumonia: Results from a claims analysis

INTRODUCTION

Antibiotic treatment failure contributes to the economic and humanistic burdens of community-acquired pneumonia (CAP) by increasing morbidity, mortality, and healthcare costs. This study compared treatment failure rates of levofloxacin with those of other antibiotics in a large US sample.

METHODS

Medical and pharmacy claims in the nationally representative SDI database were used to identify adults with a new outpatient diagnosis of CAP receiving a study antibiotic (levofloxacin, amoxicillin/clavulanate, azithromycin, moxifloxacin) between September 1, 2005 and March 31, 2008. Treatment failure was defined as ≥1 of the following events ≤30 days after index date: a refill for the index antibiotic after completed days of therapy, a different antibiotic dispensed >1 day after the index prescription, or hospitalization with a pneumonia diagnosis or emergency department visit >3 days postindex. Cohorts were propensity score matched for demographic and clinical characteristics. Treatment failure rates were compared between pairs of cohorts for the full sample and for high-risk patients (age ≥65 and/or on Medicaid).

RESULTS

Among the 3994 study patients, the numbers of dispensed index prescriptions were 268 for amoxicillin/clavulanate, 1609 for azithromycin, 1460 for levofloxacin, and 657 for moxifloxacin. Unadjusted treatment failure rates for the sample were 20.8% for levofloxacin, 23.9% for amoxicillin/clavulanate, 23.9% for azithromycin, and 19.9% for moxifloxacin. For high-risk patients, unadjusted treatment failure rates were 19.1% for levofloxacin, 26.1% for amoxicillin/clavulanate, 26.3% for azithromycin, and 24.3% for moxifloxacin. Propensity score-matched treatment failure rates were significantly lower with levofloxacin than azithromycin (19.8% vs. 24.5%, odds ratio [OR] comparator vs. levofloxacin 1.38; 95% CI: 1.14, 1.67), a difference amplified in high-risk patients (19.0% vs. 26.4%, OR 1.61; 95% CI: 1.22, 2.13). No significant differences were observed for other paired comparisons.

CONCLUSION

In a large US sample, treatment failure in CAP appeared to be less likely with quinolones (such as levofloxacin) than azithromycin, an effect particularly marked in high-risk patients (age ≥65 and/or on Medicaid).

Burden of community-acquired pneumonia in North American adults

To determine the burden of community-acquired pneumonia (CAP) affecting adults in North America, a comprehensive literature review was conducted to examine the incidence, morbidity and mortality, etiology, antibiotic resistance, and economic impact of CAP in this population. In the United States, there were approximately 4.2 million ambulatory care visits for pneumonia in 2006. Pneumonia and influenza continue to be a common cause of death in the United States (ranked eighth) and Canada (ranked seventh). In 2005, there were >60,000 deaths due to pneumonia in persons aged>or=15 years in the United States alone. The hospitalization rate for all infectious diseases increased from 1525 hospitalizations per 100 000 persons in 1998 to 1667 per 100 000 persons in 2005. Admission to an intensive care unit was required in 10% to 20% of patients hospitalized with pneumonia. The mean length of stay for pneumonia was >or=5 days and the 30-day rehospitalization rate was as high as 20%. Mortality was highest for CAP patients who were hospitalized; the 30-day mortality rate was as high as 23%. All-cause mortality for CAP patients was as high as 28% within 1 year. Streptococcus pneumoniae continues to be the most frequently identified pathogen associated with CAP, and pneumococcal resistance to antimicrobials may make treatment more difficult. The economic burden associated with CAP remains substantial at >$17 billion annually in the United States. Despite the availability and widespread adherence to recommended treatment guidelines, CAP continues to present a significant burden in adults. Furthermore, given the aging population in North America, clinicians can expect to encounter an increasing number of adult patients with CAP. Given the significance of the disease burden, the potential benefit of pneumococcal vaccination in adults is substantial.

Health economics of use fluoroquinolones to treat patients with community-acquired pneumonia

Respiratory diseases account for approximately 10% of all hospital admissions in the United States. Pneumonia constitutes 35% of these cases, with an average length of stay (LOS) of 5.1 days. It is estimated that $8.4 billion to $10 billion of all annual US hospital expenditures are attributable to community-acquired pneumonia (CAP). As such, medical decisions, including empiric antibiotic choice, potentially exert an impact on hospital LOS and associated costs. In this review, we focus on the empiric antibiotic choices and associated costs of treatment for hospitalized patients with CAP, focusing on the use of fluoroquinolone therapy as recommended by the CAP guidelines.

Hospital visits and costs following outpatient treatment of CAP with levofloxacin or moxifloxacin

BACKGROUND

Hospital admissions (inpatient and emergency room) are a major source of medical costs for community-acquired pneumonia (CAP) initially treated in the outpatient setting. Current CAP treatment guidelines do not differentiate between outpatient treatment with levofloxacin and moxifloxacin.

OBJECTIVE

Compare health care resource use and medical costs to payers for CAP outpatients initiating treatment with levofloxacin or moxifloxacin.

RESEARCH DESIGN AND METHODS

CAP episodes were identified in the PharMetrics database between 2Q04 and 2Q07 based on: pneumonia diagnosis, chest X-ray and treatment with levofloxacin or moxifloxacin. Subsequent 30-day risk of pneumonia-related hospital visits and 30-day health care costs to payers for levofloxacin vs. moxifloxacin treatment were estimated after adjusting for pre-treatment demographics, health care resource use and pneumonia-specific risk factors using propensity score and exact factor matching.

RESULTS

A total of 15,472 levofloxacin- and 6474 moxifloxacin-initiated CAP patients were identified. Among 6352 matched pairs, levofloxacin treatment was associated with a 35% reduction in the odds of pneumonia-related hospital visits (odds ratio = 0.65, P = 0.004), lower per-patient costs for pneumonia-related hospital visits (102 dollars vs. 210 dollars, P = 0.001), lower pneumonia-related total costs (medical services and prescription drugs, 363 dollars vs. 491 dollars, P < 0.001) and lower total costs (1308 dollars vs. 1446 dollars, P < 0.001) vs. moxifloxacin over the 30-day observation period.

LIMITATIONS

Although observational analyses of claims data provide large sample sizes and reflect routine care, they do have several inherent limitations. Since randomization of subjects is not possible, adequate statistical techniques must be used to ensure that patient characteristics are well-balanced between treatment groups. In addition, data may be missing or miscoded.

CONCLUSIONS

CAP outpatients initiated with levofloxacin generated substantially lower costs to payers compared to matched patients initiated with moxifloxacin. The cost savings for patients initiated with levofloxacin were largely attributable to reduced rates of pneumonia-related hospitalization or ER visits.

The importance of clinical variables in comparative analyses using propensity-score matching: the case of ESA costs for the treatment of chemotherapy-induced anaemia

BACKGROUND

The erythropoiesis-stimulating agents (ESAs) epoetin alfa (EA) and darbepoetin alfa (DA) have comparable efficacy in treating chemotherapy-induced anaemia (CIA). Therapy choice depends on many factors, including cost. Previous estimates of ESA cost differences have been derived from claims data. These data lack clinical variables, such as baseline haemoglobin (Hb) level, which are likely to influence choice of ESA, dosing and costs. We estimated cost differences between DA and EA in patients with cancer receiving chemotherapy, using a propensity-score matched analysis of baseline patient characteristics with and without Hb values to assess the effect of this clinical variable on ESA cost estimates.

METHODS

Data were extracted from electronic medical records in two US databases between January 2004 and December 2006. The study sample included 6743 patients receiving chemotherapy, with one or more visits during the study period, who received an ESA during a chemotherapy episode. Episodes of chemotherapy care were constructed using a 90-day gap in administration to identify the start and end. Patients receiving both DA and EA during their initial chemotherapy episode or with missing data were excluded, representing 42% of patients with CIA receiving an ESA. Drug costs were calculated from the cumulative dose multiplied by 106% of the average sales price (ASP) for DA or EA. Two propensity-score matches were conducted: first using variables available in administrative billing claims systems, then adding the baseline Hb test result. Regression-adjusted cost differences were estimated with and without baseline Hb, using generalized linear models.

RESULTS

Using baseline Hb levels resulted in a better match of the baseline characteristics for the EA and DA treatment groups than the original sample or the matched sample without Hb variables. Mean ESA costs (year 2007 values) for the original sample were $US4171 for EA and $US3811 for DA (mean difference $US360; p < 0.001, standard error [SE] $US99). With propensity-score matching without Hb variables, mean estimated costs were $US3836 for EA and $US3599 for DA (mean difference $US237; p = 0.053, SE $US123). With propensity-score match including Hb variables, mean costs were $US3965 for EA and $US3536 for DA (mean difference $US429; p = 0.001, SE $US125). Cost differences in sensitivity analyses ranged between $US102 (p = 0.201) and $US261 (p = 0.003).

CONCLUSIONS

Addition of baseline Hb level as a variable in propensity score and ESA cost models affects ESA treatment cost estimates in patients with cancer receiving chemotherapy. Cost comparisons based on observational data should use analytical methods that account for differences in clinical variables between treatment groups.