Management of influenza in patients with asthma or chronic obstructive pulmonary disease

Efficacy of oseltamivir compared with zanamivir in COPD patients with seasonal influenza virus infection: a randomized controlled trial

Influenza viruses exacerbate chronic obstructive pulmonary disease (COPD) with considerable morbidity and mortality. Zanamivir and oseltamivir are effective in treating influenza. However, their efficacy in relieving influenza symptoms in COPD patients remains unknown, with the lack of controlled trials in this subject. Therefore, we conducted this randomized controlled trial to investigate the clinical efficacy of both interventions in this population. Patients were allocated to two groups (80 patients each): oseltamivir (OSELTA) and zanamivir (ZANA) groups. Oseltamivir (75 mg) was orally administered twice daily for 5 days, while zanamivir (10 mg) was inhaled twice daily for 5 days. Clinical parameters including body temperature, influenza symptoms (i.e., sore throat, cough, etc.), and serial blood tests were recorded on days 1, 3, and 7. We analyzed primary (changes in body temperature) and secondary outcomes (changes in non-specific symptoms) using the pre-protocol and intention-to-treat analyses. Differences between groups were assessed using t-test. Oseltamivir and zanamivir significantly reduced body temperature on the 3rd day after treatment; however, the number of patients who reported clinical improvement in influenza-like symptoms was significantly higher in the OSELTA group compared to the ZANA group on days 3 (85 vs 68.8%, P=0.015) and 7 (97.5 vs 83.8%, P=0.003). However, no significant changes in hematological (white blood cells and its subtypes) and inflammatory (C-reactive protein) parameters were noted (P>0.05). Our results suggested that oseltamivir and zanamivir are effective in reducing body temperature, while oseltamivir led to better clinical improvement regarding influenza-like symptoms in patients with COPD.

Antivirals for Virus Induced Exacerbations of Asthma and COPD Treatment

Viral respiratory infections in patients with asthma or chronic obstructive pulmonary disease (COPD) can cause severe exacerbations, increasing the risk of secondary bacterial infections and having a significant impact on disease-related morbidity and mortality. Several antivirals such as oseltamivir and zanamivir evaluated in influenza and other virus-induced respiratory infections are discussed in this review as a starting point of their potential use in improving the outcome of asthma and COPD exacerbations. However, the efficacy of antiviral therapy for asthma/COPD exacerbations needs a further evaluation.

Influenza burden, prevention, and treatment in asthma-A scoping review by the EAACI Influenza in asthma task force

To address uncertainties in the prevention and management of influenza in people with asthma, we performed a scoping review of the published literature on influenza burden; current vaccine recommendations; vaccination coverage; immunogenicity, efficacy, effectiveness, and safety of influenza vaccines; and the benefits of antiviral drugs in people with asthma. We found significant variation in the reported rates of influenza detection in individuals with acute asthma exacerbations making it unclear to what degree influenza causes exacerbations of underlying asthma. The strongest evidence of an association was seen in studies of children. Countries in the European Union currently recommend influenza vaccination of adults with asthma; however, coverage varied between regions. Coverage was lower among children with asthma. Limited data suggest that good seroprotection and seroconversion can be achieved in both children and adults with asthma and that vaccination confers a degree of protection against influenza illness and asthma-related morbidity to children with asthma. There were insufficient data to determine efficacy in adults. Overall, influenza vaccines appeared to be safe for people with asthma. We identify knowledge gaps and make recommendations on future research needs in relation to influenza in patients with asthma.

Review on the impact of pregnancy and obesity on influenza virus infection

A myriad of risk factors have been linked to an increase in the severity of the pandemic H1N1 2009 influenza A virus [A(H1N1)pdm09] including pregnancy and obesity where death rates can be elevated as compared to the general population. The goal of this review is to provide an overview of the influence of pregnancy and obesity on the reported cases of A(H1N1)pdm09 virus infection and of how the concurrent presence of these factors may have an exacerbating effect on infection outcome. Also, the hypothesized immunologic mechanisms that contribute to A(H1N1)pdm09 virus severity during pregnant or obese states are outlined. Identifying the mechanisms underlying the increased disease severity in these populations may result in improved therapeutic approaches and future pandemic preparedness.

Using Medicaid claims to identify children with asthma

OBJECTIVE

To assess the accuracy of using administrative data from state-managed programs to identify children with asthma in a statewide immunization information system. We wished to understand the degree to which alternative asthma case definitions applied to administrative data influence the accuracy of cases identified in an immunization information system.

DESIGN & SETTING

Children aged 2 to 18 years were sequentially classified into 3-case definition groups on the basis of Michigan Department of Community Health administrative data (2005-2006): (1) children with a Children's Special Health Care Services (CSHCS) Program qualifying diagnosis of asthma (CSHCS cases); (2) those having 1 or more asthma medication claims (Rx cases); or (3) those without asthma medications having 1 or more health services claim reporting an asthma diagnosis code (Dx cases).

PARTICIPANTS

Children were randomly selected from each asthma case definition group; parents were invited to participate in a telephone interview to document physician diagnosis of asthma, symptoms, activity limitations, medications, and asthma health services use.

MAIN OUTCOME MEASURES

The positive predictive value of parent report of a physician diagnosis of asthma; asthma severity, based on National Asthma Education and Prevention Program criteria.

RESULTS

: Of 440 completed interviews, 89% of parents confirmed the child's high-risk status, reporting physician diagnosis of asthma (83%), wheezy-cough (5%), or reactive airway disease (1%). The positive predictive value varied for CSHCS cases (100%), Rx cases (91%) and Dx cases (73%, P < .0001). Although reported asthma severity levels were similar among CSHCS and Rx cases (P = .9100), asthma severity was lower among Dx cases (P = .0218).

CONCLUSIONS

Medicaid administrative data can be used to accurately identify children with asthma and represents a feasible approach for Medicaid programs and health plans to identify priority groups for targeted influenza vaccination reminders.

Les inhibiteurs de neuraminidase face au risque de grippe aviaire

Oseltamivir and zanamivir are highly potent inhibitors of influenza A and B neuraminidase and operate by inhibiting viral replication, and more specifically, the release and the movement of the virus through mucus. Neuraminidase inhibitors reduce the severity and duration of symptoms, and prevent clinical influenza as post-exposure and seasonal prophylaxis. Both have similar efficacy; oseltamivir has a more convenient route of administration, and zanamivir a more favourable resistance profile. Pending availability of effective vaccines, neuraminidase inhibitors are the only specific antiviral drugs which might be opposed to a possible pandemic that could emerge from the current highly pathogenic H5N1 virus. Although the effectiveness of oseltamivir and zanamivir for the therapy of clinical H5N1 influenza is questionable, simulation models suggest that a combination of targeted antiviral prophylaxis and quarantine might be able to contain an emerging influenza strain at the source. As a consequence, after an initial lack of commercial success probably related to the mild intensity of seasonal influenza during the last winters, neuraminidase inhibitors are now stockpiled by many countries to prepare for an outbreak.

Occasional review: influenza in COPD: pathogenesis, prevention, and treatment

Influenza viruses cause respiratory tract infections that in patients with underlying lung diseases such as chronic obstructive pulmonary disease (COPD) are associated with exacerbations and excess morbidity and mortality. Typically, influenza B is associated with relatively mild, local outbreaks, whereas influenza A is the cause of world-wide pandemics. Upon infection, two antigens present on the viral surface, hemagglutinin and neuraminidase result in human immunity, but since many subtypes of these antigens exist that vary over time, immunity in the population is blunted. Vaccination is advocated in high-risk groups including patients with underlying (lung) diseases and in the elderly, and needs to be repeated annually with vaccines expected to cover the expected change in viral antigenicity. When started early, antiviral drugs, especially neuraminidase-inhibitors can be prescribed in adjunct to nonspecific interventions in an attempt to shorten disease duration and to prevent complications in case of an influenza infection. Currently, the effectiveness of antiviral drugs specifically in patients with COPD has not been proven.

Asthma exacerbations. 2: aetiology

The natural history of asthma involves relatively stable periods that are often punctuated by significant exacerbations of symptoms. There are many aetiologies that may lead to an increase in asthma severity including respiratory infection (bacterial/viral), allergens, irritants, and occupational exposures. Each trigger probably acts through different mechanisms, but a final common pathway of multicellular inflammation, enhanced bronchial responsiveness, and airflow obstruction is a likely consequence. This review discusses the most common causes of asthma exacerbations with a focus on their microbiology and immunopathogenesis. Through an understanding of underlying causes of asthma exacerbations, treatments with increased effectiveness may be developed, and it is these future developments that may directly influence the morbidity and mortality of the disease.

Immune response to influenza vaccination in children and adults with asthma: effect of corticosteroid therapy

BACKGROUND

Annual influenza vaccination is currently recommended as a preventative measure for all patients with asthma. However, the effect of maintenance corticosteroid therapy on the immune response to influenza vaccine has received limited evaluation.

OBJECTIVE

In this study, we evaluated the effect of corticosteroid therapy on the immune response to influenza vaccine in children and adults with asthma.

METHODS

This was a substudy of a larger multicenter, randomized, double-masked, placebo-controlled, crossover study investigating the safety of trivalent influenza vaccine in patients with asthma. At baseline, 294 subjects were randomized to receive either placebo first (n=139) or inactivated trivalent split-virus influenza vaccine first (n=155). Study subjects were categorized into 2 groups: subjects in group 1 (n=148) were receiving medium-dose or high-dose inhaled corticosteroids (ICSs) or oral corticosteroids, whereas subjects in group 2 (n=146) were not receiving corticosteroids or were receiving low-dose ICSs. Serum hemagglutination inhibition antibody titers for the vaccine antigens were measured before and 4 weeks after the administration of placebo or vaccine.

RESULTS

Serologic responses to each influenza vaccine antigen were significantly higher in vaccine than in placebo recipients and were similar among influenza vaccine recipients in groups 1 and 2 for the following endpoints: rise in antibody titer, percent of participants who developed a serological response, and percent of subjects who developed a serum hemagglutination inhibition antibody titer > or =1:32. Post hoc subgroup analyses demonstrated an attenuated response to influenza B antigen in subjects receiving high-dose ICS compared with subjects who were steroid-naïve (P<.05).

CONCLUSION

The immune response to the A antigens of the inactivated influenza vaccine in subjects with asthma is not adversely affected by ICS therapy. High-dose ICS therapy may diminish the response to the B antigen of the vaccine, an observation that needs further investigation.

National availability of influenza vaccine among medical subspecialty practices

BACKGROUND

Influenza vaccination rates fall short of national goals, particularly among individuals whose chronic conditions predispose them to complications of influenza. Availability of influenza vaccine in medical subspecialists' practices may affect vaccination rates among adults with chronic illness.

METHODS

The practice sites of a national random sample of medical cardiology, endocrinology, and pulmonology physicians were contacted by telephone in February 2003 to March 2003 to determine which of them had influenza vaccine available to their patients during the 2002-2003 influenza season. The number of physicians in the practice and geographic location were also obtained.

RESULTS

Office staff at the practices of 1683 of 2013 eligible physicians were successfully contacted, and 1473 provided information about vaccine availability. Overall, 1094 (74%) of practices had influenza vaccine available during the 2002-2003 season. Availability differed significantly by subspecialty: 54% cardiology, 78% endocrinology, and 90% pulmonology (p<0.001). Influenza vaccine was more often available at subspecialists' practices in the Northeast (80%) than in the South (74%), Midwest (71%), and West (70%; p<0.005). In multivariate analyses, pulmonology practices in all census regions and sizes were significantly more likely to have influenza vaccine available than was the reference cardiology practice. Several endocrinology practice types also had significantly higher influenza vaccine availability than those in cardiology practice, particularly in multi-physician practices.

CONCLUSIONS

Influenza vaccine availability varies widely across practices in the three medical subspecialties that provide care to the largest numbers of individuals with an indication for the vaccine in the United States. These findings have implications for the accessibility of influenza vaccine to individuals at high risk for morbidity and mortality associated with influenza.

Therapy for chronic obstructive pulmonary disease in the 21st century

Chronic obstructive pulmonary disease (COPD) is a common, smoking-related, severe respiratory condition characterised by progressive, irreversible airflow limitation. Current treatment of COPD is symptomatic, with no drugs capable of halting the relentless progression of airflow obstruction. Better understanding of the airway inflammation, oxidative stress and alveolar destruction that characterise COPD has delineated new disease targets, with consequent identification of novel compounds with therapeutic potential. These new drugs include aids to smoking cessation (e.g. bupropion) and improvements to existing therapies, for example long-acting rather than short-acting bronchodilators, as well as combination therapy. New antiproteases include acyl-enzyme and transition state inhibitors of neutrophil elastase (e.g. sivelestat and ONO-6818), matrix metalloprotease inhibitors (e.g. batimastat), cathepsin inhibitors and peptide protease inhibitors (e.g. DX-890 [EPI-HNE-4] and trappin-2). New antioxidants include superoxide dismutase mimetics (e.g. AEOL-10113) and spin trap compounds (e.g. N-tert-butyl-alpha-phenylnitrone). New anti-inflammatory interventions include phosphodiesterase-4 inhibitors (e.g. cilomilast), inhibitors of tumour necrosis factor-alpha (e.g. humanised monoclonal antibodies), adenosine A(2a) receptor agonists (e.g. CGS-21680), adhesion molecule inhibitors (e.g. bimosiamose [TBC1269]), inhibitors of nuclear factor-kappaB (e.g. the naturally occurring compounds hypoestoxide and (-)-epigallocatechin-3-gallate) and activators of histone deacetylase (e.g. theophylline). There are also selective inhibitors of specific extracellular mediators such as chemokines (e.g. CXCR2 and CCR2 antagonists) and leukotriene B(4) (e.g. SB201146), and of intracellular signal transduction molecules such as p38 mitogen activated protein kinase (e.g. RWJ67657) and phosphoinositide 3-kinase. Retinoids may be one of the few potential treatments capable of reversing alveolar destruction in COPD, and a number of compounds are in clinical trial (e.g. all-trans-retinoic acid). Talniflumate (MSI-1995), an inhibitor of human calcium-activated chloride channels, has been developed to treat mucous hypersecretion. In addition, the purinoceptor P2Y(2) receptor agonist diquafosol (INS365) is undergoing clinical trials to increase mucus clearance. The challenge to transferral of these new compounds from preclinical research to disease management is the design of effective clinical trials. The current scarcity of well characterised surrogate markers predicts that long-term studies in large numbers of patients will be needed to monitor changes in disease progression.