Bénédicte Leynaert

Rhinitis and onset of asthma: a longitudinal population-based study

BACKGROUND A close relation between asthma and allergic rhinitis has been reported by several epidemiological and clinical studies. However, the nature of this relation remains unclear. We used the follow-up data from the European Community Respiratory Health Survey to investigate the onset of asthma in patients with allergic and non-allergic rhinitis during an 8.8-year period. METHODS We did a longitudinal population-based study, which included 29 centres (14 countries) mostly in western Europe. Frequency of asthma was studied in 6461 participants, aged 20-44 years, without asthma at baseline. Incident asthma was defined as reporting ever having had asthma confirmed by a physician between the two surveys. Atopy was defined as a positive skin-prick test to mites, cat, Alternaria, Cladosporium, grass, birch, Parietaria, olive, or ragweed. Participants were classified into four groups at baseline: controls (no atopy, no rhinitis; n=3163), atopy only (atopy, no rhinitis; n=704), non-allergic rhinitis (rhinitis, no atopy; n=1377), and allergic rhinitis (atopy+rhinitis; n=1217). Cox proportional hazards models were used to study asthma onset in the four groups. FINDINGS The 8.8-year cumulative incidence of asthma was 2.2% (140 events), and was different in the four groups (1.1% (36), 1.9% (13), 3.1% (42), and 4.0% (49), respectively; p<0.0001). After controlling for country, sex, baseline age, body-mass index, forced expiratory volume in 1 s (FEV(1)), log total IgE, family history of asthma, and smoking, the adjusted relative risk for asthma was 1.63 (95% CI 0.82-3.24) for atopy only, 2.71 (1.64-4.46) for non-allergic rhinitis, and 3.53 (2.11-5.91) for allergic rhinitis. Only allergic rhinitis with sensitisation to mite was associated with increased risk of asthma independently of other allergens (2.79 [1.57-4.96]). INTERPRETATION Rhinitis, even in the absence of atopy, is a powerful predictor of adult-onset asthma.

Impact of gender on asthma in childhood and adolescence: a GA2LEN review.

A number of studies have shown gender differences in the prevalence of wheeze and asthma. The aim of this review was to examine published results on gender differences in childhood and adolescent asthma incidence and prevalence, define current concepts and to identify new research needs.

Exposure to substances in the workplace and new-onset asthma: an international prospective population-based study (ECRHS-II)

BACKGROUND The role of exposure to substances in the workplace in new-onset asthma is not well characterised in population-based studies. We therefore aimed to estimate the relative and attributable risks of new-onset asthma in relation to occupations, work-related exposures, and inhalation accidents. METHODS We studied prospectively 6837 participants from 13 countries who previously took part in the European Community Respiratory Health Survey (1990-95) and did not report respiratory symptoms or a history of asthma at the time of the first study. Asthma was assessed by methacholine challenge test and by questionnaire data on asthma symptoms. Exposures were defined by high-risk occupations, an asthma-specific job exposure matrix with additional expert judgment, and through self-report of acute inhalation events. Relative risks for new onset asthma were calculated with log-binomial models adjusted for age, sex, smoking, and study centre. FINDINGS A significant excess asthma risk was seen after exposure to substances known to cause occupational asthma (Relative risk=1.6, 95% CI 1.1-2.3, p=0.017). Risks were highest for asthma defined by bronchial hyper-reactivity in addition to symptoms (2.4, 1.3-4.6, p=0.008). Of common occupations, a significant excess risk of asthma was seen for nursing (2.2, 1.3-4.0, p=0.007). Asthma risk was also increased in participants who reported an acute symptomatic inhalation event such as fire, mixing cleaning products, or chemical spills (RR=3.3, 95% CI 1.0-11.1, p=0.051). The population-attributable risk for adult asthma due to occupational exposures ranged from 10% to 25%, equivalent to an incidence of new-onset occupational asthma of 250-300 cases per million people per year. INTERPRETATION Occupational exposures account for a substantial proportion of adult asthma incidence. The increased risk of asthma after inhalation accidents suggests that workers who have such accidents should be monitored closely.

Allergic rhinitis, rhinosinusitis, and asthma: one airway disease

Asthma and allergies, including rhinoconjunctivitis and atopic dermatitis, are common throughout the world, with a high burden of morbidity and cost. The nasal and bronchial mucosa present similarities, and most patients with asthma also have rhinitis, suggesting the concept of one airway, one disease. Not all patients with rhinitis present with asthma, however, and there are differences between rhinitis and asthma. For this article, the authors differentiate between chronic rhinosinusitis and nasal polyposis based on the presence of polyps in the nasal cavity or the sinuses during clinical examination or surgery. This approach neglects an ill-defined group of chronic hyperplastic sinusitis, which might represent a transition phase.

Smoking cessation, lung function, and weight gain : a follow-up study

BACKGROUND Only one population-based study in one country has reported effects of smoking cessation and weight change on lung function, and none has reported the net effect. We estimated the net benefit of smoking cessation, and the independent effects of smoking and weight change on change in ventilatory lung function in the international European Community Respiratory Health Survey. METHODS 6654 participants in 27 centres had lung function measured in 1991-93, when aged 20-44 years, and in 1998-2002. Smoking information was obtained from detailed questionnaires. Changes in lung function were analysed by change in smoking and weight, adjusted for age and height, in men and women separately and together with interaction terms. FINDINGS Compared with those who had never smoked, decline in FEV1 was lower in male sustained quitters (mean difference 5.4 mL per year, 95% CI 1.7 to 9.1) and those who quit between surveys (2.5 mL, -1.9 to 7.0), and greater in smokers (-4.8 mL, -7.9 to -1.6). In women, estimates were 1.3 mL per year (-1.5 to 4.1), 2.8 mL (-0.8 to 6.3) and -5.1 mL (-7.5 to -2.8), respectively. These sex differences were not significant. FEV1 changed by -11.5 mL (-13.3 to -9.6) per kg weight gained in men, and by -3.7 mL per kg (-5.0 to -2.5) in women, which diminished the benefit of quitting by 38% in men, and by 17% in women. INTERPRETATION Smoking cessation is beneficial for lung function, but maximum benefit needs control of weight gain, especially in men.

Association of bronchial hyperresponsiveness and lung function with C-reactive protein (CRP): a population based study.

Background: C-reactive protein (CRP), a marker of systemic inflammation, is a powerful predictor of adverse cardiovascular events. Respiratory impairment is also associated with cardiovascular risk. Although some studies have found an inverse relationship between lung function and markers of systemic inflammation, only one study has reported a relationship between lung function and CRP levels. In contrast, little is known about the relationship between bronchial hyperresponsiveness (BHR) and systemic inflammation. The association between lung function and CRP and between BHR and CRP has been investigated. Methods: As part of the European Community Respiratory Health Survey follow up study serum CRP levels, forced expiratory volume in 1 second (FEV1), and BHR to methacholine (⩾20% decrease in FEV1 to <4 mg methacholine) were measured in 259 adults aged 28–56 years free of cardiovascular disease or respiratory infection. Results: Mean (SD) FEV1 (adjusted for age, sex, height, and smoking status) was lower in subjects with a high CRP level (high tertile) (3.29 (0.44) l/s v 3.50 (0.44) l/s; p<0.001) and BHR was more frequent (41.9% v 24.9%; p = 0.005) than in subjects with lower CRP levels (low+middle tertiles). Similar results were obtained when the potential confounding factors were taken into account. Similar patterns of results were found in non-smokers and in non-asthmatic subjects. Conclusions: Increased CRP levels are strongly and independently associated with respiratory impairment and more frequent BHR. These results suggest that both respiratory impairment and BHR are associated with a systemic inflammatory process.

Important research questions in allergy and related diseases: nonallergic rhinitis: a GA2LEN paper

 Nonallergic rhinitis (NAR) can be defined as a chronic nasal inflammation which is not caused by systemic IgE‐dependent mechanisms. It is common and probably affects far more than 200 million people worldwide. Both children and adults are affected. However, its exact prevalence is unknown and its phenotypes need to be evaluated using appropriate methods to better understand its pathophysiology, diagnosis and management. It is important to differentiate between infectious rhinitis, allergic/NAR and chronic rhinosinusitis, as management differs for each of these cases. Characterization of the phenotype, mechanisms and management of NAR represents one of the major unmet needs in allergic and nonallergic diseases. Studies on children and adults are required in order to appreciate the prevalence, phenotype, severity and co‐morbidities of NAR. These studies should compare allergic and NAR and consider different age group populations including elderly subjects. Mechanistic studies should be carried out to better understand the disease(s) and risk factors and to guide towards an improved diagnosis and therapy. These studies need to take the heterogeneity of NAR into account. It is likely that neuronal mechanisms, T cells, innate immunity and possibly auto‐immune responses all play a role in NAR and may also contribute to the symptoms of allergic rhinitis.

Increase in diagnosed asthma but not in symptoms in the European Community Respiratory Health Survey

Background: Information on the epidemiology of asthma in relation to age is limited and hampered by reporting error. To determine the change in the prevalence of asthma with age in young adults we analysed longitudinal data from the European Community Respiratory Health Survey. Methods: A self-administered questionnaire was completed by 11 168 randomly selected subjects in 14 countries in 1991–3 when they were aged 20–44 years and 5–11 years later from 1998 to 2003. Generalised estimating equations were used to estimate net change in wheeze, nocturnal tightness in chest, shortness of breath, coughing, asthma attacks in the last 12 months, current medication, “diagnosed” asthma, and nasal allergies. Results: Expressed as change in status per 10 years of follow up, subjects reporting asthma attacks in the previous 12 months increased by 0.8% of the population (95% CI 0.2 to 1.4) and asthma medication by 2.1% (95% CI 1.6 to 2.6), while no statistically significant net change was found in reported symptoms. Reported nasal allergies increased, especially in the youngest age group. Conclusions: As this cohort of young adults has aged, there has been an increase in the proportion treated for asthma but not in the proportion of those reporting symptoms suggestive of asthma. Either increased use of effective treatments has led to decreased morbidity among asthmatic subjects or those with mild disease have become more likely to label themselves as asthmatic.

Risk factors for chronic obstructive pulmonary disease in a European cohort of young adults.

RATIONALE Few studies have investigated the factors associated with the early inception of chronic obstructive pulmonary disease (COPD). OBJECTIVES We investigated COPD risk factors in an international cohort of young adults using different spirometric definitions of the disease. METHODS We studied 4,636 subjects without asthma who had prebronchodilator FEV(1)/FVC measured in the European Community Respiratory Health Survey both in 1991 to 1993 (when they were 20-44 yr old) and in 1999 to 2002. COPD was defined according to the Global Initiative for Chronic Obstructive Lung Disease fixed cut-off criterion (FEV(1)/FVC < 0.70), and two criteria based on the Quanjer and LuftiBus reference equations (FEV(1)/FVC less than lower limit of normal). COPD determinants were studied using two-level Poisson regression models. MEASUREMENTS AND MAIN RESULTS COPD incidence ranged from 1.85 (lower limit of normal [Quanjer]) to 2.88 (Global Initiative for Chronic Obstructive Lung Disease) cases/1,000/yr. Although about half of the cases had smoked less than 20 pack-years, smoking was the main risk factor for COPD, and it accounted for 29 to 39% of the new cases during the follow-up. Airway hyperresponsiveness was the second strongest risk factor (15-17% of new cases). Other determinants were respiratory infections in childhood and a family history of asthma, whereas the role of sex, age, and of being underweight largely depended on the definition of COPD used. CONCLUSIONS COPD may start early in life. Smoking prevention should be given the highest priority to reduce COPD occurrence. Airway hyperresponsiveness, a family history of asthma, and respiratory infections in childhood are other important determinants of COPD. We suggest the need for a definition of COPD that is not exclusively based on spirometry.

Is age at menopause increasing across Europe? : results on age at menopause and determinants from two population-based studies

Objective: To investigate the variability and determinants of menopause age in two European cohort studies, the European Respiratory Health Survey and the Swiss Air Pollution and Lung Disease in Adults Cohort. Methods: Age at menopause was estimated in 5,288 women, aged 30 to 60 years, randomly selected in nine European countries between 1998 and 2002. Determinants of natural and surgically induced menopause were investigated by Cox regression and heterogeneity by meta-analysis. Follicle-stimulating hormone and luteinizing hormone levels were assessed in a subsample. Results: A quarter of the women were postmenopausal by age 50.8 years. Median age of natural menopause was 54 years. Hormone levels were within expected ranges for premenopausal and postmenopausal women. Surgically induced menopause was highly prevalent (22%-47%), associated with earlier timing of menopause. Determinants of earlier menopause were current smoking (hazard ratio [HR], 1.59; 95% CI, 1.27-1.98), body mass index greater than 30 kg/m2 (HR, 1.32; 95%, CI, 1.02-1.70), and low physical activity (HR, 1.37; 95%, CI, 1.12-1.67). The determinant for later menopause was multiparity (HR, 0.74; 95% CI, 0.62-0.89). Predictors were similar for naturally and surgically induced menopause. Oral contraceptive use yielded heterogeneous effects on timing of menopause. Later birth was associated with later menopause (HR, 0.934; 95% CI, 0.91-0.96). This evidence of a secular trend is heterogeneous across countries. Conclusions: Age at menopause varies across Europe, shifting toward higher ages. This secular trend seems paradoxical because several adult determinants, that is, overweight, smoking, sedentarity, and nulliparity, associated with early menopause are on the rise in Europe. The heterogeneity of the secular trend suggests additional country-specific factors not included in the study, such as improved childhood nutrition and health, that have an influence on reproductive aging.