Acute exacerbations of chronic bronchitis in elderly patients: pathogenesis, diagnosis and management

Intranasal coinfection model allows for assessment of protein vaccines against nontypeable Haemophilus influenzae in mice

PURPOSE

Nontypeable Haemophilus influenzae (NTHi) is a commensal in the human nasopharynx and the cause of pneumonia, meningitis, sinusitis, acute exacerbations of chronic obstructive pulmonary disease and acute otitis media (AOM). AOM is the most common ailment for which antibiotics are prescribed in the United States. With the emergence of new strains of antibiotic-resistant bacteria, finding an effective and broad coverage vaccine to protect against AOM-causing pathogens has become a priority. Mouse models are a cost-effective and efficient way to help determine vaccine efficacy. Here, we describe an NTHi AOM model in C57BL/6J mice, which also utilizes a mouse-adapted H1N1 influenza virus to mimic human coinfection.

METHODOLOGY

We tested our coinfection model using a protein vaccine formulation containing protein D, a well-studied NTHi vaccine candidate that can be found in the 10-valent Streptococcus pneumoniae conjugate vaccine. We verified the usefulness of our mouse model by comparing bacterial loads in the nose and ear between protein D-vaccinated and control mice.

RESULTS

While there was no measurable difference in nasal bacterial loads, we did detect significant differences in the bacterial loads of ear washes and ear bullae between vaccinated and control mice.

CONCLUSION

The results from this study suggest that our NTHi AOM coinfection model is useful for assessing protein vaccines.

Cefditoren versus levofloxacin in patients with exacerbations of chronic bronchitis: serum inflammatory biomarkers, clinical efficacy, and microbiological eradication

Background

The aim of this open-label, randomized, parallel-group pilot study was to evaluate the efficacy of cefditoren pivoxil and levofloxacin in terms of speed of reduction in inflammatory parameters, clinical recovery, and microbiological eradication.

Methods

Forty eligible patients with acute exacerbation of chronic bronchitis (AECB) were randomized to receive cefditoren 200 mg twice a day for 5 days (n = 20) or levofloxacin 500 mg once daily for 7 days (n = 20).

Results

The inflammatory parameters which were significantly reduced at test-of-cure with respect to visit 1 were Krebs von den Lundgen-6 (KL-6) and interleukin-6. KL-6 decreased both in the overall study population (from 19 ± 11 UI/mL to 6 ± 8 UI/mL, P = 0.000) and in the cefditoren (from 19 ± 13 UI/mL to 8 ± 10 UI/mL, P = 0.006) and levofloxacin (from 19 ± 10 UI/mL to 5 ± 5 UI/mL, P = 0.000) arms. Similarly, interleukin-6 decreased both in the overall study population (from 13.35 ± 16.41 pg/mL to 3 ± 4.7 pg/mL, P = 0.000) and in the cefditoren (from 15.90 ± 19.54 pg/mL to 4.13 ± 6.42 pg/mL, P = 0.015) and levofloxacin (from 10.80 ± 12.55 pg/mL to 1.87 ± 1.16 pg/mL, P = 0.003) arms. At the end of treatment (test-of-cure, 6–9 days after drug initiation), the clinical success rate in the overall study population was 78%; the clinical cure rate was 80% in the cefditoren arm and 75% in the levofloxacin arm. Globally, bacteriological eradication at test-of-cure was obtained in 85% of the overall study population. Both treatments were well tolerated.

Conclusion

Cefditoren represents a valid option in the treatment of mild to moderately severe cases of AECB in the outpatient care setting. Moreover, the use of this cephalosporin is associated with a significant reduction of interleukin-6 and KL-6, two key mediators of lung inflammation and epithelial damage.

Utility of NT-proBNP for identifying LV failure in patients with acute exacerbation of chronic bronchitis

BACKGROUND

NT-proBNP has been widely regarded as a useful tool for diagnosis or exclusion of heart failure (HF) in many settings. However, in patients with acute exacerbation of chronic bronchitis (AECB), its roles have not been well described. The objective of this study was to evaluate the diagnostic performance of NT-proBNP for identifying left ventricular (LV) failure in such patients.

METHODS AND RESULTS

311 AECB patients and 102 stable chronic bronchitis patients with no history of HF were enrolled. Plasma NT-proBNP concentrations were measured using Roche Elecsys. The European Society of Cardiology (ESC) diagnostic principles were adopted to identify HF and the diagnostic performance of NT-proBNP was evaluated by ROC. Our results showed, the median NT-proBNP level in patients with LV failure [4828.4 (2044.4-9203.6) ng/L] was significantly higher than that in those without LV failure [519.2 (179.1-1409.8) ng/L, p<0.001] and stable controls [207.5 (186.5-318.2) ng/L, p<0.001]. LV failure, renal function, atrial fibrillation and systolic pulmonary artery pressure were independent predictors of NT-proBNP levels (all p<0.05). The area under ROC curve (AUC) of NT-proBNP for identifying LV failure was 0.884, significantly superior to clinical judgment alone (AUC 0.835, p = 0.0294). At the optimal cutoff value of 935.0 ng/L, NT-proBNP yielded sensitivity 94.4%, specificity 68.2%, accuracy 74.3% and negative predictive value 97.6%. Adding the results of NT-proBNP to those of clinical judgment improved the diagnostic accuracy for LV failure.

CONCLUSION

As a tool for diagnosis or exclusion of HF, NT-proBNP can help physicians identify LV failure in patients with AECB.

Antibiotic therapy in elderly patients with acute exacerbation of chronic bronchitis

Chronic bronchitis (CB) is a critical component of chronic obstructive pulmonary disease (COPD). Emphysema, reversible airway disease and bronchiectasis also contribute to COPD. Elderly patients are at increased risk for COPD and its components - emphysema, CB and bronchiectasis. In addition, older patients are at increased risk for resistant organisms during episodes of acute exacerbation of CB (AECB). These organisms include the more common bacteria implicated in AECB, such as Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae, and less common nonenteric, Gram-negative organisms such as Pseudomonas aeruginosa. Risk-stratified antibiotic treatment guidelines for AECB appear to be useful, although they have not been prospectively validated for the general CB population, and especially not in the elderly CB population. Many of the AECB treatment guidelines that are stratified based on risk factors have recommended that the oral respiratory fluoroquinolone antibiotics (gemifloxacin, levofloxacin and moxifloxacin) play a second-line but pivotal role, particularly in patients who have failed initial antibiotic treatment for simple CB or as initial treatment for complicated CB.

Low concentrations of serum 25-hydroxyvitamin D associated with increased risk for chronic bronchitis among US adults

Increasing evidence suggests that vitamin D benefits both innate and adaptive immunity, thereby eliciting an anti-inflammatory effect and reducing the risk of infectious disease. The present study examined the association between serum 25-hydroxyvitamin D (25(OH)D) levels and the risk of chronic bronchitis among US adults. We analysed data from 6872 US adults aged ≥ 20 years who participated in the 2003-6 National Health and Nutrition Examination Survey. Prevalence and OR with 95 % CI of having self-reported chronic bronchitis were estimated by quintiles of 25(OH)D or vitamin D-deficiency status after adjustment for potential confounders. The results showed that the adjusted prevalence of chronic bronchitis ranged from 2.4 (95 % CI 1.4, 3.3) % among adults in the highest quintile of 25(OH)D ( ≥ 30 ng/ml) to 4.1 (95 % CI 2.5, 5.6) % among adults in the lowest quintile ( < 15 ng/ml; P for trend < 0.01). The adjusted OR for chronic bronchitis was 1.85 (95 % CI 1.06, 3.24) in adults with < 15 ng/ml 25(OH)D and 1.77 (95 % CI 1.19, 2.65) in those with 15 to < 20 ng/ml 25(OH)D compared with adults with ≥ 30 ng/ml 25(OH)D. Additionally, the adjusted OR for chronic bronchitis was 1.52 (95 % CI 1.03, 2.26) among adults with vitamin D deficiency ( < 20 ng/ml 25(OH)D) compared with those with ≥ 20 ng/ml 25(OH)D. For every 1 ng/ml increase in 25(OH)D, the likelihood of having chronic bronchitis fell by 2.6 % (P = 0.016). In conclusion, low serum 25(OH)D levels are associated with the increased risk of chronic bronchitis among US adults. The present results provide support for continuing research on the role of vitamin D in lung diseases.

Adherence to controller therapy for chronic obstructive pulmonary disease: a review

OBJECTIVE

While several studies have examined adherence to controller medications for the treatment of COPD, few systematic reviews have taken the translational step to identifying important and necessary areas for further research. The objective of this study was to review data on the outcomes of adherence to various controller therapies in patients with COPD in an effort to help prescribers understand adherence properties for each therapy.

RESEARCH DESIGN AND METHODS

This is a systematic review of studies investigating adherence to an array of controller pharmaceutical regimens. The studies were obtained from PubMed during 2008 and 2009 using the following key words: chronic obstructive pulmonary disease, COPD, adherence, controller medication, and persistence. Only articles encompassing adherence or persistence data to controller medications and published after 1990 were utilized.

RESULTS

After the search results were filtered for only the articles that pertained to adherence or persistence measurements in COPD, 35 articles remained; and finally, discounting those articles not published in English, articles which did not compare treatments for COPD, as well as those which were review articles, ten applicable articles remained. Each of these found low levels of medication adherence and/or persistence among patients receiving medications for COPD. Patients receiving fluticasone/salmeterol (FSC) and tiotropium (TIO) for treatment showed the highest adherence among all controller medications. Patients who were married, older, and white were more likely to adhere to their medications.

CONCLUSION

Characteristics of the medication used (i.e. dosing schedule, formulation, etc.) as well as patient characteristics affect the adherence/persistence to medications for the treatment of COPD. Further patient education is necessary in order to effectively improve disease management and patient outcomes in COPD. There is a need for future research and educational efforts to improve adherence in COPD and more clearly identify specific behavioral and treatment characteristics associated with specific COPD medications that can facilitate adherence.

Effect of steady-state enoxacin on single-dose pharmacokinetics of roflumilast and roflumilast N-oxide

Roflumilast is an oral phosphodiesterase 4 (PDE4) inhibitor for the treatment of chronic obstructive pulmonary disease (COPD). It is metabolized by CYP1A2 and CYP3A4 to its primary metabolite, roflumilast N-oxide, through which >90% total PDE4 inhibitory activity (tPDE4i) is mediated. Fluoroquinolones, of which enoxacin is the most potent CYP1A2 inhibitor, are used to treat COPD exacerbations. This phase I, open, nonrandomized, fixed-sequence, 2-period study evaluated the effects of steady-state enoxacin on the single-dose pharmacokinetics of roflumilast and roflumilast N-oxide. Twenty healthy participants received roflumilast, 500 µg once daily, on days 1 and 12, and enoxacin, 400 mg twice daily, on days 7 to 18. Pharmacokinetic profiles were obtained for days 1 to 6 and 12 to 19. The safety and tolerability of all treatments were also assessed. In 19 evaluable participants, coadministration led to 56% higher mean systemic exposure, 20% higher mean peak concentrations, and 36% lower mean apparent oral clearance compared with roflumilast alone. For roflumilast N-oxide, 23% higher mean systemic exposure and 14% lower mean peak concentrations were seen after coadministration. Roflumilast was well tolerated both alone and in combination with enoxacin. A weak interaction was shown between roflumilast and enoxacin, as mean tPDE4i increased by 25%, but is unlikely to have clinical relevance.

The diagnosis and treatment of elderly patients with acute exacerbation of chronic obstructive pulmonary disease and chronic bronchitis

The syndrome of chronic obstructive pulmonary disease (COPD) consists of chronic bronchitis (CB), bronchiectasis, emphysema, and reversible airway disease that combine uniquely in an individual patient. Older patients are at risk for COPD and its components—emphysema, CB, and bronchiectasis. Bacterial and viral infections play a role in acute exacerbations of COPD (AECOPD) and in acute exacerbations of CB (AECB) without features of COPD. Older patients are at risk for resistant bacterial organisms during their episodes of AECOPD and AECB. Organisms include the more‐common bacteria implicated in AECOPD/AECB such as Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. Less‐common nonenteric, gram‐negative organisms including Pseudomonas aeruginosa, gram‐positive organisms including Staphylococcus aureus, and strains of nontuberculosis Mycobacteria are more often seen in AECOPD/AECB episodes involving elderly patients with frequent episodes of CB or those with bronchiectasis. Risk‐stratified antibiotic treatment guidelines appear useful for purulent episodes of AECOPD and episodes of AECB. These guidelines have not been prospectively validated for the general population and especially not for the elderly population. Using a risk‐stratification approach for elderly patients, first‐line antibiotics (e.g., amoxicillin, ampicillin, pivampicillin, trimethoprim/sulfamethoxazole, and doxycycline), with a more‐limited spectrum of antibacterial coverage, are used in patients who are likely to have a low probability of resistant organisms during AECOPD/AECB. Second‐line antibiotics (e.g., amoxicillin/clavulanic acid, second‐ or third‐generation cephalosporins, and respiratory fluoroquinolones) with a broader spectrum of coverage are reserved for patients with significant risk factors for resistant organisms and those who have failed initial antibiotic treatment.

Experimental pulmonary infection and colonization of Haemophilus influenzae in emphysematous hamsters

BACKGROUND

Bacterial infection has been considered the main cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). However, experimental model of COPD exacerbation induced by Haemophilus influenzae infection was not available up to now. Furthermore, only a few studies on evaluation of antibiotics using an H. influenzae infection model in mice have been reported. The aim of this work was to evaluate the activity of moxifloxacin on experimental pulmonary infection and colonization of H. influenzae in emphysematous hamsters.

METHODS

Pulmonary emphysema was developed by intratracheal instillation of porcine pancreatic elastase in golden hamsters, which were infected by agar-beads enclosing H. influenzae to establish animal models of AECOPD. Alterations of lung histopathology, inflammatory factor levels in plasma and bronchoalveolar lavage fluids (BALFs), viable cell counting of lung tissue were determined on different days after challenge and moxifloxacin administration.

RESULTS

Lung bacterial counts of BALFs and homogenates were significantly higher in emphysematous hamsters than those in normal non-emphysematous animals from 1 to 3 weeks after intratracheal inoculation of bacterial agar-beads suspensions. Moreover, H. influenzae colonized and survived for a longer period of time in emphysematous lungs than in normal non-emphysematous lungs after challenge. Efficacy of 3-day intragastric administration of moxifloxacin was proved by reduction in pulmonary H. influenzae burden and alleviation of inflammatory responses on days 4, 8 and 21 post-inoculation. No planktonic bacteria were isolated from BALFs in the first week after moxifloxacin treatment, and bacterial load in lung tissue homogenates declined significantly. Nevertheless, after 3 weeks, bacterial load in BALFs and homogenates of emphysematous lungs recovered to a large quantity. Inflammation in lung tissue, including lung consolidation, hemorrhage, and neutrophils infiltration, was conspicuously improved after administration of moxifloxacin. Levels of inflammatory factors in plasma were significantly decreased on days 8 and 21 after treatment compared with that without drug therapy. Inflammatory factors in BALF were also reduced, among which IL-8 dropped down markedly in early stage.

CONCLUSION

Our results suggest that chronic bacterial infection and colonization is highly correlated with lung emphysematous lesions, which would be one of the important mechanisms for repeated attacks of acute exacerbations of chronic pulmonary diseases and uncertain efficacies of antibiotics.

Healthcare use and costs in patients with chronic bronchitis initiating maintenance therapy with fluticasone/salmeterol vs other inhaled maintenance therapies

OBJECTIVE

To compare risk of hospitalization or emergency department (ED) visit and healthcare costs in patients with chronic bronchitis initiating inhaled maintenance therapy with fluticasone propionate/salmeterol 250/50 mcg combination (FSC) versus other inhaled maintenance therapies.

DESIGN AND METHODS

This retrospective cohort study assessed 9,217 patients from the PharMetrics administrative claims database enrolled from July 1997 to January 2005. Study subjects were persons with medical claims with diagnoses of chronic bronchitis (ICD-9-CM 491.xx) who also had pharmacy claims for FSC, salmeterol (SAL), inhaled corticosteroid (ICS), ipratropium (IPR), or ipratropium/albuterol combination (IAC). Persons with <12 months of continuous eligibility after the first prescription for initial maintenance therapy ("index date") were excluded as were those receiving fluticasone propionate/salmeterol 100/50 mcg or 500/50 mcg (not indicated for patients with chronic bronchitis). For remaining persons, time to first hospitalization or ED visit during follow-up was compared for those receiving FSC versus other therapies using Cox proportional hazards regression. Healthcare costs during the first 12 months of follow-up were analyzed using generalized linear model regression.

RESULTS

Receipt of FSC as initial inhaled maintenance therapy for chronic bronchitis (n = 1361) was associated with 41% lower risk of COPD-related hospitalization or ED visit compared with IPR (n < 1316) (p < 0.001). Adjusted costs of COPD-related hospitalization/ED visit were $507 (95% CI $218-$1083) less with FSC than IPR. However, patients receiving FSC had $261 (95% CI $205-$322) higher COPD-related pharmacy costs than those receiving IPR. Total COPD-related costs were $90 lower with FSC than IPR although this difference was not significant (95% CI $330-$443). Compliance, as measured by medication possession ratio, was 12% greater with FSC compared with IPR (p < 0.05). Comparisons of FSC with IAC yielded generally similar results. The limitations of the study are similar to those of other observational studies of secondary data regarding potential misclassification and omitted variable bias and residual confounding.

CONCLUSIONS

In persons with chronic bronchitis, initial maintenance therapy with FSC 250/50 mcg was associated with improved outcomes versus ipratropium-based therapy and although FSC was associated with greater pharmacy costs, it did not significantly increase total costs of COPD-related care.