Late onset asthma: epidemiology, diagnosis and treatment

Differentiating asthma and tracheal stenosis: why confirmation of the diagnosis of asthma should precede treatment

INTRODUCTION

Asthma is a common respiratory condition; however, its symptoms often overlap with other diseases, posing diagnostic challenges. Tracheal stenosis, often seen in patients with a history of intubation, can mimic asthma symptoms, leading to misdiagnosis.

CASE STUDY

This case study discusses a 58-year-old female with hypertension, type 2 diabetes, and obesity. She was initially treated for presumed asthma for over a year without confirming the diagnosis with pulmonary function tests (PFTs). Despite multiple steroid treatments for exacerbations, her condition deteriorated, leading to hospitalization. During hospitalization, her symptoms were minimally improved with steroid and nebulizer treatments. Examination revealed inspiratory stridor, and a subsequent CT scan identified subglottic tracheal stenosis. Flexible bronchoscopy confirmed the stenosis, successfully treated with balloon dilation. Post-procedure, her PFTs showed mild obstruction without bronchodilator response, her shortness of breath resolved, and her exercise tolerance improved markedly without ongoing asthma treatment.

DISCUSSION

Asthma symptoms, including dyspnea, wheezing, cough, and chest tightness, frequently overlap with tracheal stenosis. Early differentiation is crucial to avoid misdiagnosis, reduce unnecessary treatments, and prevent complications. Recognizing risk factors, such as obesity, diabetes, female gender, and prior intubation, and employing diagnostic tools, such as PFTs and CT scan of the neck help diagnose tracheal stenosis. Prompt bronchoscopy and appropriate intervention can dramatically improve patient outcomes.

CONCLUSION

This case underscores the importance of heightened clinical suspicion and comprehensive diagnostic evaluation in patients with persistent treatment-resistant asthma-like symptoms, particularly those with a history of intubation, for timely diagnosis of tracheal stenosis.

Asthma prevalence based on the Baidu index and China's Health Statistical Yearbook from 2011 to 2020 in China

Background

Due to environmental pollution, changes in lifestyle, and advancements in diagnostic technology, the prevalence of asthma has been increasing over the years. Although China has made early efforts in asthma epidemiology and prevention, there is still a lack of unified and comprehensive epidemiological research within the country. The objective of the study is to determine the nationwide prevalence distribution of asthma using the Baidu Index and China's Health Statistical Yearbook.

Methods

Based on China's Health Statistical Yearbook, we analyzed the gender and age distribution of asthma in China from 2011 to 2020, as well as the length of hospitalization and associated costs. By utilizing the Baidu Index and setting the covering all 31 provinces and autonomous regions in China, we obtained the Baidu Index for the keyword 'asthma'. Heatmaps and growth ratios described the prevalence and growth of asthma in mainland China.

Results

The average expenditure for discharged asthma (standard deviation) patients was ¥5,870 (808). The average length of stay (standard deviation) was 7.9 (0.38) days. During the period of 2011 to 2020, hospitalization expenses for asthma increased while the length of hospital stay decreased. The proportion of discharged patients who were children under the age of 5 were 25.3% (2011), 19.4% (2012), 16% (2013), 17.9% (2014), 13.9% (2015), 11.3% (2016), 10.2% (2017), 9.4% (2018), 8.1% (2019), and 7.2% (2020), respectively. The prevalence of asthma among boys was higher than girls before the age of 14. In contrast, the proportion of women with asthma was larger than men after the age of 14. During the period from 2011 to 2020, the median [The first quartile (Q1)-the third quartile (Q3)] daily asthma Baidu index in Guangdong, Beijing, Jiangsu, Sichuan, and Zhejiang were 419 (279-476), 328 (258-376), 315 (227-365), 272 (166-313), and 312 (233-362) respectively. Coastal regions showed higher levels of attention toward asthma, indicating a higher incidence rate. Since 2014, there has been a rapid increase in the level of attention toward asthma, with the provinces of Qinghai, Sichuan, and Guangdong experiencing the fastest growth.

Conclusion

There are regional variations in the prevalence of asthma among different provinces in China, and the overall prevalence of asthma is increasing.

Association of weight-adjusted-waist index with asthma prevalence and the age of first asthma onset in United States adults

Objective

The objective of this study was to assess whether the weight-adjusted-waist index(WWI) is associated with the prevalence of asthma and age when first asthma onset appears in US adults.

Methods

For analysis we selected participants from the National Health and Nutrition Examination Survey(NHANES)database between 2001 and 2018. A dose-response curve was calculated using logistic regression,subgroup analysis,and a dose-response curve.

Results

The study included 44480 people over the age of 20,including 6061 reported with asthma, and the increase in asthma prevalence was 15% associated with each unit increase in the WWI, after adjusting for all confounders(odds ratio(OR)=1.15,95% CI:1.11,1.20). The sensitivity analysis was performed by trichotomizing the WWI, and compared to the lowest tertile, the highest tertile WWI group displayed a 29% increase in asthma prevalence(OR=1.29,95% CI:1.19,1.40). A nonlinear correlation was found between the WWI index and the risk of asthma onset, with a threshold saturation effect indicating an inflection point of 10.53 (log-likelihood ratio test, P<0.05), as well as a positive linear correlation with age at first asthma onset.

Conclusions

A higher WWI index was associated with an increased prevalence of asthma and an older age of first asthma onset.

Expert consensus recommendations for the management of asthma in older adults

Asthma is a public health problem in patients of any age, although there is still a tendency to erroneously assume that it is almost always confined to children and young people. Epidemiological studies indicate that, from the sixth decade of life, the prevalence of this disease in countries such as Spain reaches 6-10%, with a higher prevalence among women aged 64 to 75 years. In addition, two-thirds of asthma deaths occur at this stage of life, resulting in a substantial number of hospital admissions, longer hospital stays and, from a finance point of view, significant direct economic costs. Asthma in older adults (65 years or older) is now a matter of great concern, the reality of which is underestimated and undertreated. It is therefore essential to establish appropriate recommendations for the diagnosis and treatment of asthma in the aging population. This consensus, which brings together the latest evidence available, was conceived with this objective. The proposed recommendations/conclusions are the result of a nominal consensus developed throughout 2019 and validated by panellists in successive rounds of voting.

The Role of Atopy in COPD and Asthma

Common to several allergic diseases is the generation of immunoglobulin E (IgE) by plasma cells, when exposed to an innocuous antigen. Asthma and chronic obstructive pulmonary disease (COPD) are two prevalent chronic airway inflammatory diseases. Asthma is mediated in some patients through eosinophilic inflammatory mechanisms that include allergic sensitization and Th2-mediated immune airway response. COPD, on the other hand is mainly considered a Th1-mediated inflammatory process with neutrophilic predominance or a non-Th2 inflammation, occasionally associated with the presence of airway bacteria or viruses. IgE production appears to play an important role in the development of both COPD and asthma, as it has been associated to respiratory symptoms, lung function, bacterial and viral infections, airway remodeling and bronchial hyperreactivity in both diseases. The aim of this review is to summarize all current data concerning the role of specific and total IgE in COPD and asthma and to highlight similarities and differences in view of possible therapeutic interventions.

Long-term exposure to fine particulate matter and incident asthma among elderly adults

RATIONALE

Although an association of fine particulate matter (PM_2.5) with asthma incidence has been assumed, there is insufficient evidence regarding the effect of long-term exposure to PM_2.5 on incident asthma among elderly adults.

OBJECTIVES

This study aimed to investigate an association between long-term exposure to PM_2.5 and incident asthma among elderly adults in South Korea.

METHODS

Adults ≥65 years of age (n = 1,220,645) who did not visit hospitals for asthma during a washout period (between 2008 and 2010) were followed up until 2016 using data from the National Health Insurance System in South Korea. Incident asthma was defined as the number of patients with a primary diagnostic code of asthma who visited hospitals more than twice. We linked the health data with district-level PM_2.5 concentrations and estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for incident asthma after adjusting for potential confounders in time-varying Cox proportional hazard models.

MEASUREMENTS AND MAIN RESULTS

Over 5,942,256 person-years, 54,522 patients developed asthma, with an incidence of 9.2 cases/1000 person-years. A 10 μg/m³ increase in the 36-month mean PM_2.5 concentration was significantly associated with a 9% increase in incident asthma (HR = 1.09, 95% CI: 1.04-1.14). This association was found to be robust for different definitions of incident asthma and washout periods.

CONCLUSION

Long-term exposure to PM_2.5 was associated with the incidence of asthma in elderly adults. This finding provides evidence of an association between PM_2.5 and adult-onset asthma.

Geographic and demographic variations of inhalant allergen sensitization in Koreans and non-Koreans

BACKGROUND

To diagnose and treat respiratory allergic diseases, it is important to identify the specific allergens involved. Many differences exist between common inhalant allergens depending on the residential environment and demographic factors. This study aimed to compare common inhalant allergens between Koreans and non-Koreans according to their residential region, age, and sex.

METHODS

This study evaluated 15,334 individuals who underwent serum tests for multiple allergen-specific immunoglobulin E at a tertiary academic medical center between January 2010 and December 2016. The individuals included 14,786 Koreans and 548 non-Koreans. The AdvanSure™ Allostation assay (LG Life Science, Korea) was used to test for 33 inhalant allergens.

RESULTS

The house dust mite (HDM) was the most common allergen in both Koreans and non-Koreans, although the proportion of individuals with HDM sensitization was greater among Koreans. High sensitization rates for various pollen types were detected among Koreans in Gangwon region, whereas Japanese cedar pollen was unique among Koreans in Jeju region. Grass pollen and animal dander were relatively common among individuals from the Americas, whereas weed and grass pollen accounted for the 10 most common allergens for individuals from Central Asia. The total sensitization rate, sensitization to HDM, and sensitization to animal dander peaked among adolescents and young adults, then subsequently decreased with age.

CONCLUSIONS

This large-scale study demonstrates that various regional and age-related differences exist in the allergen sensitization rates of Koreans and non-Koreans. These data could be useful for development of avoidance measures, immunotherapy for causative allergens, and policymaking regarding allergic diseases.

Major depressive disorder is associated with subsequent adult-onset asthma: a population-based cohort study

AIM

To examine the incidence of asthma in adult patients with major depressive disorder (MDD).

METHODS

From the National Health Insurance database of Taiwan, we identified 30 169 adult patients who were newly diagnosed with MDD between 2000 and 2010. Individuals without depression were randomly selected four times and frequency matched for sex, age and year of diagnosis. Both cohorts were followed-up for the occurrence of asthma up to the end of 2011. Adjusted hazard ratios (aHRs) of asthma were estimated using the Cox proportional hazards method.

RESULTS

The overall incidence of asthma was 1.91-fold higher in the MDD cohort than in the non-depression cohort (7.55 v. 3.96 per 1000 person-years), with an aHR of 1.66 (95% confidence interval (CI) 1.55-1.78). In both cohorts, the incidence of asthma was higher in patients and controls who were female, aged, with comorbidities and users of aspirin or beta-adrenergic receptor blockers. No significant difference was observed in the occurrence of asthma between patients with MDD treated with selective serotonin reuptake inhibitors (SSRIs) and those treated with non-SSRIs (SSRIs to non-SSRIs aHR = 1.03, 95% CI 0.91-1.17).

CONCLUSION

Adult patients with MDD are at a higher risk of asthma than those without depression are.

New concepts in asthma: clinical phenotypes and pathophysiological mechanisms

Asthma is among the most common chronic inflammatory diseases worldwide. Recent evidence indicates that the pathogenesis shows a high degree of heterogeneity. Patient subsets have been identified that exhibit different cellular and molecular patterns of dysregulation. A prominent example is eosinophilic Th2-driven asthma. These unique and molecular patterns are termed endotypes. Characterization of endotypes has broad implications for therapeutic interventions. Although ∼80% of asthmatic patients respond well to standard anti-inflammatory therapies, the remaining subset particularly consisting of severe patients requires a more specialized endotype-specific approach. This interrelationship between clinical phenotypes, molecular endotypes and endotype-specific therapies is the focus of this review.

Old dilemma: asthma with irreversible airway obstruction or COPD

Older asthmatic patients may develop fixed airway obstruction and clinical signs of chronic obstructive pulmonary disease (COPD). We investigated the added value of pathological evaluation of bronchial biopsies to help differentiate asthma from COPD, taking into account smoking, age, and inhaled corticosteroid (ICS) use. Asthma and COPD patients (24 of each category) were matched for ICS use, age, FEV₁, and smoking habits. Five pulmonary and five general pathologists examined bronchial biopsies using an interactive website, without knowing patient information. They were asked to diagnose asthma or COPD on biopsy findings in both a pairwise and randomly mixed order of cases during four different phases, with intervals of 4–6 weeks, covering a maximal period of 36 weeks. Clinically concordant diagnoses of asthma or COPD varied between 63 %-73 %, without important differences between pairwise vs randomly mixed examination or between general vs pulmonary pathologists. The highest percentage of concordant diagnoses was in young asthmatic patients without ICS use and in COPD patients with ICS use. In non ICS users with fixed airway obstruction, a COPD diagnosis was favored if abnormal presence of glands, squamous metaplasia, and submucosal infiltrate was present and an asthma diagnosis in case of abnormal presence of goblet cells. In ICS users with fixed airway obstruction, abnormal presence of submucosal infiltrates, basement membrane thickening, eosinophils, and glands was associated with asthma. Histological characteristics in bronchial biopsies are reproducibly recognized by pathologists, yet the differentiation by histopathology between asthma and COPD is difficult without information about ICS use.

Management of allergic disease in the elderly: key considerations, recommendations and emerging therapies

The number of people over 65 is increasing around the world. At present, between 5 and 10% of allergic diseases affect the elderly. In particular, rhinitis is increasing worldwide; the presence of high comorbidity makes the therapy of asthma even more complicated. With reference to dermatological allergies, the dryness of the skin favors the onset of allergic contact and atopic dermatitis, while the senescence of mucous membranes and the impaired secretion of polymeric IgA could be linked to food allergy. Overcoming the problem of adverse drug reaction is limited by the diagnostic difficulty in patients taking multiple drugs. In addition, some drugs, such as β-blockers, angiotensin-converting enzyme (ACE)-inhibitors and NSAIDs, are relevant factors of urticaria and anaphylaxis. The aim of this review is to provide updated diagnostic and therapeutic guidelines through a better understanding of the pathophysiologic mechanisms, preventive measures and adherence to therapy.

Biomarkers of progression of chronic obstructive pulmonary disease (COPD)

Disease progression of chronic obstructive pulmonary disease (COPD) is variable, with some patients having a relatively stable course, while others suffer relentless progression leading to severe breathlessness, frequent acute exacerbations of COPD (AECOPD), respiratory failure and death. Radiological markers such as CT emphysema index, bronchiectasis and coronary artery calcification (CAC) have been linked with increased mortality in COPD patients. Molecular changes in lung tissue reflect alterations in lung pathology that occur with disease progression; however, lung tissue is not routinely accessible. Cell counts (including neutrophils) and mediators in induced sputum have been associated with lung function and risk of exacerbations. Examples of peripheral blood biological markers (biomarkers) include those associated with lung function (reduced CC-16), emphysema severity (increased adiponectin, reduced sRAGE), exacerbations and mortality [increased CRP, fibrinogen, leukocyte count, IL-6, IL-8, and tumor necrosis factor α (TNF-α)] including increased YKL-40 with mortality. Emerging approaches to discovering markers of gene-environment interaction include exhaled breath analysis [volatile organic compounds (VOCs), exhaled breath condensate], cellular and systemic responses to exposure to air pollution, alterations in the lung microbiome, and biomarkers of lung ageing such as telomere length shortening and reduced levels of sirtuins. Overcoming methodological challenges in sampling and quality control will enable more robust yet easily accessible biomarkers to be developed and qualified, in order to optimise personalised medicine in patients with COPD.

Diagnosis and management of asthma in the elderly

Bronchial asthma is one of the most common chronic diseases worldwide, and by definition not expected to recover with aging. However, the concept that asthma can affect older individuals has been largely denied in the past. In clinical practice, asthma that occurs in the most advanced ages is often diagnosed as COPD, thus leading to undertreatment or improper treatment. The heterogeneity of clinical and functional presentation of geriatric asthma, including the partial loss of reversibility and of the allergic component, contributes to this misconception. A large body of evidence has accumulated demonstrating that the prevalence of asthma in the most advanced ages is similar to that in younger ages. The frequent coexistence of comorbid conditions in older patients compared to younger asthmatics, together with age-associated changes of the human lung, may render the management of asthma a complicated task. The article addresses the main issues related to the diagnosis and treatment of asthma in the geriatric age.

Older adults with asthma: does age of asthma onset make a difference?

OBJECTIVE

Older adults with asthma can develop symptoms early in life or during adulthood. Differences between these groups may have diagnostic and therapeutic implications. Our goal was to identify differences in demographics, control, quality of life and healthcare utilization between those with long-standing asthma (LSA) and late-onset asthma (LOA).

METHODS

Data from a cross-sectional study of asthma patients over age 65 were analyzed. LSA or LOA was based on age of diagnosis (before or after age 40). Demographic and asthma specific information were analyzed, and allergy prick tests and lung function testing (spirometry and FENO) were performed.

RESULTS

After regression analysis, LSA subjects were more likely to demonstrate positive prick tests (92 versus 71%, p = 0.04), with both groups demonstrating higher levels of atopy than previously reported. LSA subjects were also more likely to have received a peak flow meter (p = 0.07). LOA subjects were more likely to have moderate or severe asthma (OR = 3.1, p = 0.05), and had higher FENO readings (p = 0.02). They also had more hospitalizations (p = 0.04), though significance was lost after regression analysis. No differences were noted in demographic information, medical comorbidities, spirometry, compliance, asthma control, or asthma quality of life between LSA and LOA subjects.

CONCLUSION

LSA subjects are more atopic and more likely to be given a peak flow meter, while LOA subjects have higher FENO levels and more severe asthma. Defining age of asthma onset may help improve treatment recommendations and outcomes for older adults.

Interaction of occupational and personal risk factors in workforce health and safety

Most diseases, injuries, and other health conditions experienced by working people are multifactorial, especially as the workforce ages. Evidence supporting the role of work and personal risk factors in the health of working people is frequently underused in developing interventions. Achieving a longer, healthy working life requires a comprehensive preventive approach. To help develop such an approach, we evaluated the influence of both occupational and personal risk factors on workforce health. We present 32 examples illustrating 4 combinatorial models of occupational hazards and personal risk factors (genetics, age, gender, chronic disease, obesity, smoking, alcohol use, prescription drug use). Models that address occupational and personal risk factors and their interactions can improve our understanding of health hazards and guide research and interventions.

Should atopy be assessed in elderly patients with respiratory symptoms suggestive of asthma?

Aging is associated with modifications of the immune system and this could contribute to a reduced prevalence of allergic disease in the elderly. Atopy has rarely been considered in the clinical assessment of the geriatric respiratory patient. This article is a review of the available literature assessing the impact of age on atopy in the asthmatic patient. In the majority of papers, we found a lower prevalence of atopy in the most advanced ages, both in healthy subjects and in individuals affected by allergic respiratory diseases. No large, longitudinal studies performed in the general population have been conducted to confirm this observation. Although available data seem to favor the decline of allergen sensitization with age, the prevalence of allergic sensitizations in the elderly population with respiratory symptoms is substantial enough to warrant evaluation of the atopic condition. For this reason, the evaluation of the atopic condition in the geriatric patient is recommended. The role of atopy as regards diagnosis, therapy and prognosis of asthma in the elderly is addressed.

Asthma in the elderly

Bronchial asthma is a common problem with enormous medical and economics impacts. It is an inflammatory disease of the airways associated with intermittent episodes of bronchospasm. Asthma is not uncommon in the elderly patients. Prevalence of asthma is similar in older and younger adults. Asthma in the elderly patient is underdiagnosed because of false perceptions by both patient and physician. The high incidence of comorbid conditions in the elderly patient makes the diagnosis and management more difficult. Correct diagnosis is demonstrated with spirometry. The goals of asthma treatment are to achieve and maintain control of symptoms and to prevent development of irreversible airflow limitation. Asthma drugs are preferably inhaled because this route minimizes systemic absorption and, thus, improves the ratio of the therapeutic benefit to the potential side-effects in elderly patients.

Complexities of diagnosis and treatment of allergic respiratory disease in the elderly

Atopic diseases such as rhinitis and asthma are relatively common in children and young adults. However, many patients aged >65 years are also affected by these disorders. Indeed, the literature suggests that between 3-12% and 4-13% of individuals in this age range have allergic rhinitis and asthma, respectively. However, these numbers are most likely underestimates because atopic diseases are frequently not considered in older patients. The diagnosis of both allergic rhinitis and asthma in older patients is more difficult than in younger patients because of a wide differential diagnosis of other diseases that can produce similar symptoms and must be excluded. Furthermore, treatment of these disorders is complicated by the potential for drug interactions, concern about the adverse effects of medications, in particular corticosteroids, and the lack of drug trials specifically targeting treatment of older patients with allergic rhinitis and asthma.

Cardiovascular disease risk associated with asthma and respiratory morbidity might be mediated by short-acting beta2-agonists

BACKGROUND

Studies examining the asthma-related risks of cardiovascular disease (CVD) events have generally used selected samples or did not control for the effects of beta(2)-agonist use, itself associated with CVD events.

OBJECTIVES

We assessed the relationship between incident CVD/stroke and asthma and the effect of atopy while controlling for beta(2)-agonist use in a representative adult population cohort free of CVD at baseline.

METHODS

The North West Adelaide Health Study (stage 1, n = 3812; stage 2, n = 3113) assessed spirometry, anthropometry, atopy, blood pressure, and lipid levels. Questionnaires assessed doctor-diagnosed asthma and CVD (myocardial infarction and angina)/stroke, smoking status, and demographics. Asthma was defined by self-report or FEV(1) reversibility. Current short- and long-acting beta(2)-agonist use was identified at follow-up.

RESULTS

Results are expressed as odds ratios (ORs) and 95% CIs. By using multivariable logistic regression, after adjustment for risk factors, in female subjects incident CVD/stroke events were associated with asthma (OR, 3.24; 95% CI, 1.55-6.78), with no effect modification by atopy (P for interaction = .61), and with as-required short-acting beta(2)-agonist use (OR, 2.66; 95% CI, 1.06-6.61). In male subjects events were associated with daily cough/sputum (OR, 1.92; 95% CI, 1.05-3.50) and FEV(1) of less than 80% of predicted value but an FEV(1)/forced vital capacity ratio of greater than 0.70 (OR, 2.15; 95% CI, 0.91-5.09; P = .08). Although few CVD/stroke events occurred in male subjects with asthma, a significant interaction with atopic status was found (P = .05).

CONCLUSIONS

Studies are required to elucidate how asthma exposes older women to excess macrovascular risk and prospectively determine the short-acting beta(2)-agonist-related risk in persons without existing CVD. CVD risk in relation to atopic status of asthma also requires further investigation.

The relationship between psychogenic cough and the diagnosis and misdiagnosis of asthma: a review

The differential diagnoses of persistent nonproductive cough include numerous pulmonary and nonpulmonary organic disorders as well as functional illnesses. Many diseases can cause cough, and several studies have shown asthma among the most common etiologies associated with chronic cough in adult nonsmokers, as well as children. Psychogenic cough and its relationship to asthma and other asthma-like illnesses is complex since distinct maladies with similar features may coexist individually or in combination in any given patient. While chronic cough may occur as a sole presenting manifestation of bronchial asthma in all age groups, recent findings suggest that most children with persistent cough without other respiratory symptoms do not have asthma. Since several organic, as well as functional diseases, may present with persistent cough as their sole manifestation in either adults or children, cough should not be used as a single or major determinant to diagnose and treat asthma, especially when empirically focused therapy trials fail. Given the range of illnesses causing cough, no single management guideline can be expected to be universally effective.

Optimal management of asthma in elderly patients: strategies to improve adherence to recommended interventions

Adherence to asthma medications presents a problem in all age groups, and older people with chronic illnesses such as asthma also have multiple co-morbidities and consequently complex healthcare needs. It has been suggested that older people are also less likely to adhere to medication and treatment than younger people. Although the prevalence of asthma in older people is similar to that of the general population, over two-thirds of those who die from asthma are >50 years of age and there is strong evidence for under-diagnosis. Clinicians therefore face specific challenges in providing healthcare with respect to both asthma diagnosis and treatment in older age groups. Non-adherence to medication can be defined as either 'intentional' or 'unintentional'. Unintentional non-adherence is more likely to be associated with sociodemographic or physical barriers to the use of medication. Intentional non-adherence results from the balance of individual reasoning of risks versus the benefits of taking medication and acceptance of asthma diagnosis. Intentional non-adherence can be addressed through strategies that influence health beliefs and concerns about the adverse effects of medicine. Unintentional adherence can be addressed by assessing and educating the patient in relation to device use and providing education and clear written instructions about medication requirements. However, some barriers to medication use, such as financial ones, may be systematic. Most studies of medication use, efficacy, adverse effects and adherence in patients with asthma primarily involve younger people. Studies of strategies to improve asthma adherence outcomes specifically in older people are urgently needed.

Epigallocatechin-3-gallate reduces allergen-induced asthma-like reaction in sensitized guinea pigs

In this study, we have evaluated the effects of the polyphenol epigallocatechin-3-gallate (EGCG), an antioxidant molecule that also enhances constitutive nitric-oxide synthase (NOS) activity, on antigen-induced asthma-like reaction in sensitized guinea pigs. For comparison, we used epicatechin, which shares antioxidant but not NOS-modulating properties with EGCG. Ovalbumin-sensitized guinea pigs placed in a respiratory chamber were challenged with ovalbumin. EGCG (25 mg/kg b.wt.) or epicatechin (25 mg/kg b.wt.) was given i.p. 20 min before ovalbumin challenge. We analyzed latency time for the onset of respiratory abnormalities, cough severity, duration of dyspnea, lung tissue histopathology, mast cell activation (by granule release), leukocyte/eosinophilic infiltration (by major basic protein and myeloperoxidase), oxygen free radical-mediated injury (by nitrotyrosine and 8-hydroxy-2-deoxyguanosine and superoxide dismutase), NOS activity, and bronchial inflammatory response [by tumor necrosis factor-alpha in bronchoalveolar lavage (BAL)]. In the sensitized animals, severe respiratory abnormalities appeared soon after the antigen challenge, accompanied by bronchoconstriction, alveolar inflation, and a marked increase in the assayed parameters of inflammatory cell recruitment, free radical lung injury, and release of proinflammatory molecules in BAL fluid. This was associated with marked depression of constitutive NOS activity. Pretreatment with EGCG, but not epicatechin, significantly reduced all the above parameters and sustained endothelial-type NOS activity. These findings provide evidence that EGCG, probably by modulating NOS activity, can counteract allergic asthma-like reaction in sensitized guinea pigs and suggest its possible future use for the treatment of asthma.

How is the diagnosis of asthma in older people established in clinical practice?

WHAT WE NEED TO KNOW: How is breathlessness perceived and defined in older people? What impact does breathlessness have on quality of life? Can history taking and physical examination be tailored to efficiently cover all the organ systems associated with breathlessness? Can a self- or carer-rated questionnaire be used to identify asthma in patients with breathlessness? WHAT WE NEED TO DO: Develop self- and carer-rated questionnaires that measure change in function and quality of life before and after treatment. Validate objective measures of physical function and airflow that are sufficiently sensitive to measure change with treatment. Develop a diagnostic guideline in general practice that includes measures of mood and cognitive function and involves carers where necessary. Provide rehabilitation and restorative care services.

Undiagnosed asthma in older people: an underestimated problem

WHAT WE NEED TO KNOW: Are older people with respiratory symptoms aware this could be asthma? Which explanations for undiagnosed asthma apply most commonly in older Australians with asthma? Can we improve awareness of asthma in older people with undiagnosed asthma? Is the possibility of asthma in older people firmly established on the general practitioners' radar screen? What reasons most often determine whether GPs perform spirometry in their practice? WHAT WE NEED TO DO: Conduct a representative population study to assess whether older Australians recognise respiratory symptoms as being asthma and are reporting these symptoms. Conduct and evaluate a pilot asthma health promotion program for older people. Conduct a controlled therapeutic trial of people with undiagnosed asthma to assess treatment benefits and produce treatment recommendations. Identify whether the prominence of asthma in older people can be brought to the attention of GPs. Analyse more carefully the issues associated with innovation of office spirometry.

Shock, inflammation and PARP

The activation of poly(ADP-ribose) polymerase (PARP) is well considered to play an important role in various patho-physiological conditions like inflammation and shock. A vast amount of circumstantial evidence implicates oxygen-derived free radicals (especially, superoxide and hydroxyl radical) and high-energy oxidants (such as peroxynitrite) as mediators of inflammation and shock. ROS (e.g., superoxide, peroxynitrite, hydroxyl radical and hydrogen peroxide) are all potential reactants capable of initiating DNA single strand breakage, with subsequent activation of the nuclear enzyme poly(ADP-ribose) synthetase (PARS), leading to eventual severe energy depletion of the cells, and necrotic-type cell death. During the last years, numerous experimental studies have clearly demonstrated the beneficial effects of PARP inhibition in cell cultures through rodent models and more recently in pre-clinical large animal models of acute and chronic inflammation. The aim of this review is to describe recent experimental evidence implicating PARP as a pathophysiological modulator of acute and chronic inflammation.

Age of onset and the characteristics of asthma

OBJECTIVE

The aim of this study was to evaluate the characteristics of asthma in patients with different ages of disease onset.

METHODOLOGY

Five hundred and four asthmatic patients (303 males and 201 females) were divided into five groups based on age of onset (group I, age of onset < 15 years old; group II, 15-24 years old; group III, 25-44 years old; group IV, 45-64 years old; and group V, > 64 years old). The relationship between age of onset and the characteristics of asthma, including lung function, reversibility, atopic status and the incidence of coexistent allergic rhinitis was assessed. Multivariate analysis, adjusted for the duration of disease, gender, educational level, smoking status, and degree of previous inhaled corticosteroid treatment, was performed.

RESULTS

Thirty per cent of the patients developed asthma before they were 14 years old (group I), and the percentages of those developing asthma at other ages of onset were: group II, 12%; group III, 29%; group IV, 21% and group V, 8%. In all, 57.6% of the asthmatic patients had coexistent allergic rhinitis; younger patients tended to have this comorbidity. The pulmonary function of older onset asthma patients was worse than that of early onset patients. The multivariate analysis showed that there was a positive correlation between the reduction of pulmonary function and duration of the disease (P < 0.001), but there was no relationship between pulmonary function and gender (P = 0.502), educational level (P = 0.734), smoking pack-years (P = 0.902), or degree of use of inhaled corticosteroid treatment (P = 0.586).

CONCLUSION

Asthma is a heterogeneous disease with a wide variety of presentations. This study provides information about the disease characteristics and their relationship with age of onset. Further study is necessary to determine why these differences exist.

Inhibition of poly(ADP-ribose) polymerase prevents allergen-induced asthma-like reaction in sensitized Guinea pigs

Poly(ADP-ribose) polymerase (PARP) plays an important role in tissue injury in conditions associated with oxidative stress and inflammation. Because asthma is a chronic inflammatory disorder of the airways, we designed the present experimental study to evaluate the effects of PARP inhibition on allergen-induced asthma-like reaction in ovalbumin-sensitized guinea pigs. Cough and dyspnea in response to ovalbumin aerosol were absent in naive guinea pigs, whereas they became severe in the sensitized animals. In the latter ones, ovalbumin aerosol also induced a rapid increase in PARP activity, bronchiolar constriction, pulmonary air space inflation, mast cell degranulation, poly(ADP-ribose) and nitrotyrosine immunostaining, myeloperoxidase activity, and malondialdehyde in lung tissue, as well as a rise in the amounts of nitrites and tumor necrosis factor-alpha in bronchoalveolar lavage fluid. Pretreatment with the PARP inhibitors 3-aminobenzamide (10 mg/kg b.wt.) or 5-aminoisoquinolinone (0.5 mg/kg b.wt.) given i.p. 3 h before ovalbumin challenge significantly reduced the severity of cough and the occurrence of dyspnea and delayed the onset of respiratory abnormalities. Both PARP inhibitors were also able to prevent the above morphological and biochemical changes of lung tissue or bronchoalveolar lavage fluid induced by ovalbumin challenge. Conversely, p-aminobenzoic acid, the inactive analog of 3-aminobenzamide, had no effects.

Asthma phenotypes in Niue Islanders

OBJECTIVE

The aim of this study was to identify asthma phenotypes in patients of Niue Island ancestry that might be suitable for susceptibility gene mapping studies.

METHODOLOGY

Two hundred and sixteen Niue Islanders with physician-diagnosed asthma that was not secondary to other medical conditions were recruited through community organisations. Fifty-one of the subjects with asthma were resident on Niue Island and 165 in New Zealand. Each subject was interviewed and tested for atopy, serum [IgE] (5% quantile, median, 95% quantile) and lung function.

RESULTS

There were two groups of subjects defined by an age of onset of asthma less than 12 years of age (childhood-onset, boys:girls 64:65) and greater than 12 years of age (adult-onset, men:women 11:76). A positive response (wheal > 3 mm) to at least one aeroallergen was seen in 181 patients, with 168/181 (92.8%) responding to house dust mite. Twenty-eight subjects with asthma were non-atopic (no detectable wheal) and the atopy status of seven subjects with asthma could not be determined (wheal < 3 mm). In childhood-onset asthma, serum IgE levels were higher (P < 0.0001) in subjects with atopic than in subjects with non-atopic asthma. In adult-onset asthma, serum IgE levels were higher (P < 0.0001) in subjects with atopic asthma than in either subjects with non-atopic asthma or matched non-atopic subjects without asthma. The asthma phenotypes in Niue Island and New Zealand residents were similar.

CONCLUSIONS

Both atopic and non-atopic asthma phenotypes exist in Niue Islanders resident in Niue and New Zealand. The potential for mapping asthma susceptibility genes in this isolated population is discussed.

A right-sided aortic arch misdiagnosed as asthma since childhood

Congenital malformation of the aortic arch complex occurs in 3% of humans. These vascular aberrations result from embryonic structures that persist when there is incomplete atrophy or regression during normal development. Typically, anomalies of the aortic arch do not cause respiratory symptoms. However, in some individuals, the unusual position of the remnant vessels may compress the airway and cause airflow limitation. As might be expected, a symptomatic vascular anomaly is most often clinically apparent in childhood. We report an adult male with exertional dyspnea who had been diagnosed with asthma since childhood. After his symptoms proved refractory to newer asthmatic therapy, he was referred for further evaluation. Bronchial hyperactivity was not present with objective testing, and compression of his trachea by a right-sided aortic arch was confirmed with appropriate imaging studies. This report illustrates the need to confirm the diagnosis of asthma with objective measures of airflow and reminds the clinician that a congenital vascular aberrancy may initially elude diagnosis.

Non-Hodgkin's lymphoma among asthmatics exposed to pesticides

We conducted a pooled analysis of population-based case-control studies in Iowa, Minnesota and Nebraska to investigate whether asthma modifies risk of non-Hodgkin's lymphoma (NHL) associated with pesticide exposures. Cases (n = 872) diagnosed with NHL from 1980 to 1986 and frequency-matched controls (n = 2,381) randomly selected from the same geographic areas as the cases were included. Information on use of pesticides and history of asthma was based on interviews. Unconditional logistic regression was used to calculate ORs, adjusted for age, state and vital status. Of all subjects, 177 (45 cases, 132 controls) reported having been told by their doctor that they had asthma. Subjects with an asthma history had a nonsignificantly lower risk of NHL than nonasthmatics (OR = 0.6, 95% CI 0.3-1.4), and there was no main effect of pesticide exposure (OR = 1.0, 95% CI 0.8-1.2). However, asthmatics tended to have larger ORs associated with exposure to pesticides than nonasthmatics. The OR among asthmatics was 1.8 (95% CI 1.1-3.2) for ever-use of crop insecticides, 2.7 (95% CI 1.0-7.2) for chlordane, 2.4 (95% CI 1.0-5.7) for lindane and 3.7 (95% CI 1.3-10.9) for fonofos. Among nonasthmatics, ORs were 1.1 (0.9-1.3), 1.5 (1.1-2.2), 1.3 (0.97-1.8) and 1.6 (1.0-2.4), respectively. Although there is limited power for assessing interaction, our results suggest that the risk of NHL among asthmatics with pesticide exposure may be higher than among nonasthmatics with pesticide exposure.

The diagnosis and management of asthma is much tougher in older patients

Half the elderly individuals with asthma have not been diagnosed, yet their quality of life is substantially impaired. Primary care physicians should, therefore, be encouraged to ask about respiratory symptoms in elderly patients, and then perform office spirometry for those with symptoms. Airway obstruction increases the likelihood of asthma, but the lack of a 'significant' acute bronchodilator response is clinically meaningless. Methacholine challenge testing is safe and useful for detecting asthma in patients with normal baseline spirometry. Only one in five life-long smokers ever develops chronic obstructive pulmonary disease, so elderly smokers should also be evaluated for reversible airways obstruction. A normal diffusing capacity test will rule out emphysema in current and former smokers. Elderly individuals whose asthma has been diagnosed are often receiving sub-optimal treatment, resulting in poor asthma control and a high death rate. Co-morbidities (recognized or not) are the rule in elderly patients, and these conditions, or the drugs taken to treat them, may exacerbate asthma. Conversely, bronchodilators and corticosteroids used to treat asthma often worsen co-morbid conditions, such as osteoporosis, ocular disease, and cardiac arrhythmias. Therefore, extra caution is needed when treating elderly asthmatic patients, and objective monitoring of their response to each new asthma medication is important.