[Trochlearis palsy due to chronic sinusitis]

Chronic rhinosinusitis and nasal polyposis are common rhinological diagnoses. Left untreated both diseases can result in visual dysfunctions because of their close proximity to orbita. We report a rare case of an isolated trochlear nerve palsy caused by chronic sinusitis and nasal polyposis. The patient was a healthy 54-year-old woman. She was successfully managed with sinus surgery and recovered fully. Despite the rare aetiology, diseases in the sinuses should be considered in the differential diagnosis of trochlear nerve palsy.

[Ectopic tooth as a rare cause of foreign body reaction of the nose]

This is a case report of a 71-year-old male with three months of gradually increasing irritation, secretion and right-sided nasal stenosis. The patient had not experienced any facial trauma nor had he had any previous surgical intervention to the nasal or oral cavity. An examination of the nasal cavity raised the suspicion of a foreign body in the right nasal floor. A computed tomography was performed and a high-density, foreign body was identified. The patient was referred to the local department of otorhinolaryngology, where an ectopic tooth was successfully removed in local anaesthesia.

[The sweet Christmas rash]

Christmas tree hypersensitivity is a rare condition, which has so far obtained scarce attention in the medical literature. We present two clinical cases of hypersensitivity associated with Christmas tree exposure, a 51-year-old woman with allergic contact dermatitis and a 41-year-old man with allergic rhinitis. The female patient had a positive patch test reaction to colophony, and the male patient had a positive skin prick test reaction to alternaria mould. Both were successfully advised to avoid prolonged exposure to Christmas trees and buy artificial trees for Christmas.

Local pulmonary administration of factor VIIa (rFVIIa) in diffuse alveolar hemorrhage (DAH) - a review of a new treatment paradigm

Background

Diffuse alveolar hemorrhage (DAH) is a clinical syndrome with typical symptoms dyspnea and hemoptysis. DAH is a complication of specific diseases, in some cases with acute catastrophic hemoptysis, while other patients present low grade alveolar bleeding with a need of chronic transfusion as in pulmonary hemosiderosis.

Methods

Current literature in the PubMed database and other sources was reviewed in order to evaluate the current treatment recommendations, efficacy of this treatment, and finally the risk of complications after off-label use of rFVIIa in respect to DAH.

Objectives

(i) To elucidate the clinical aspects of alveolar hemorrhage, (ii) to develop a simple diagnostic algorithm in order to separate DAH from other important pulmonary diseases with similar clinical picture and comparably high mortality. Such an algorithm has important therapeutic consequences because these diseases: acute lung injury (ALI), acute respiratory distress syndrome (ARDS) and bronchiolitis obliterans organizing pneumonia (BOOP) have different therapies, (iii) to evaluate and discuss whether local pulmonary administration may improve outcome and reduce mortality in DAH, and (iv) to suggest a treatment schedule.

Results

Hitherto the diagnosis and treatment of DAH has been based on anecdotal reports. The treatment has relied on different unspecific treatment modalities based on a mixture of treatment of the underlying disease and treatment without evidence targeted to stop the alveolar bleeding. However, recently a number of publications have advocated the use of intrapulmonary rFVIIa. Even in severe bleeding DAH has been shown to respond promptly without thromboembolic complication when FVIIa was administered locally via the air side, because the FVIIa does not penetrate the alveolo-capillary membrane to the blood-side. The incidence of DAH (in the US and Europe is 100,000–150,000, and 50,000 patients annually are at risk of developing DAH following hematopoietic stem cell transplant (HSCT) and autoimmune diseases. Finally 50,000–100,000 patients may be falsely categorized as having acute respiratory distress syndrome/acute lung injury (ARDS/ALI) because DAH and ARDS cannot be separated clinically. A new treatment paradigm of DAH is proposed as no other intervention has been able to ensure pulmonary hemostasis in DAH. The diagnosis of DAH is simple, a series of broncho-alveolar washes which become increasingly bloody. This test should be performed in all patients with pulmonary opacities in order to separate ARDS/ALI from DAH. FVIIa administrated via pulmonary route is “drug of choice”, because it stops bleeding in the life-threatening syndrome DAH. Hemostasis is obtained after only one to two small doses of FVIIa (50 μg/kg body weight per dose) and after hemostasis the oxygen transport quickly improves.

Conclusion

Intrapulmonary administration of rFVIIa is recommended as the treatment of choice for DAH and blast lung injury (BLI) because the treatment has been shown to be successful and uncomplicated in spite of the fact that only a small series of DAH has been documented.

Acute radiation syndrome (ARS) - treatment of the reduced host defense

Background

The current radiation threat from the Fukushima power plant accident has prompted rethinking of the contingency plan for prophylaxis and treatment of the acute radiation syndrome (ARS). The well-documented effect of the growth factors (granulocyte colony-stimulating factor [G-CSF] and granulocyte-macrophage colony-stimulating factor [GM-CSF]) in acute radiation injury has become standard treatment for ARS in the United States, based on the fact that growth factors increase number and functions of both macrophages and granulocytes.

Methods

Review of the current literature.

Results

The lungs have their own host defense system, based on alveolar macrophages. After radiation exposure to the lungs, resting macrophages can no longer be transformed, not even during systemic administration of growth factors because G-CSF/GM-CSF does not penetrate the alveoli. Under normal circumstances, locally-produced GM-CSF receptors transform resting macrophages into fully immunocompetent dendritic cells in the sealed-off pulmonary compartment. However, GM-CSF is not expressed in radiation injured tissue due to defervescence of the macrophages. In order to maintain the macrophage’s important role in host defense after radiation exposure, it is hypothesized that it is necessary to administer the drug exogenously in order to uphold the barrier against exogenous and endogenous infections and possibly prevent the potentially lethal systemic infection, which is the main cause of death in ARS.

Recommendation

Preemptive treatment should be initiated after suspected exposure of a radiation dose of at least <2 Gy by prompt dosing of 250–400 μg GM-CSF/m² or 5 μg/kg G-CSF administered systemically and concomitant inhalation of GM-CSF < 300 mcg per day for at least 14–21 days.

Conclusion

The present United States standard for prevention and treatment of ARS standard intervention should consequently be modified into the combined systemic administration of growth factors and inhaled GM-CSF to ensure the sustained systemic and pulmonary host defense and thus prevent pulmonary dysfunction.

The immunomodulatory effect of inhaled granulocyte-macrophage colony-stimulating factor in cystic fibrosis. A new treatment paradigm

BACKGROUND

Patients with cystic fibrosis (CF) experience recurrent infections and develop chronically infected lungs, which initiates an altered immunological alveolar environment. End-stage pulmonary dysfunction is a result of a long sequence of complex events in CF, progressing to alveolar macrophage dysfunction via a T-helper 2 (T(H)2) dominated alveolar inflammation with CD20 T-cell activation, induced by the chronic infection and showing a poor prognosis. There is great potential for treatment in transforming the T(H)2 into the more favorable T-helper 1 (T(H)1) response.

METHODS

Current literature in the PubMed database and other sources was reviewed in order to evaluate aspects of the innate alveolar host defense mechanisms and the potential impact on the immunoinflammatory response of inhalation of granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with CF.

RESULTS

It seems that the cellular host defense, (ie, the alveolar macrophage and neutrocyte function) and the inhaled GM-CSF interact in such a way that the so-called tolerant alveolar environment dominated by the T(H)2 response may be transformed into an active T(H)1 state with a normal pulmonary host defense. The shift of the T(H)2 to the T(H)1 subset dominated by specific and unspecific antibodies may be achieved after the inhalation of GM-CSF. A clinical report has shown promising results with inhalation of GM-CSF in a chronically-infected CF patient treated with several antibacterial and antifungal agents. Inhaled GM-CSF transformed the tolerance toward the Gram-negative infection reflected by the so-called T(H)2 subset into the more acute T(H)1 response characterized by recruitment of the T-cells CD8 and CD16, a condition related to better-preserved lung function. This indicated a transformation from a state of passive bacterial tolerance toward the Gram-negative infecting and colonizing bacteria. This GM-CSF effect cannot be achieved by administering the drug via the IV route because the drug is water-soluble and too large to penetrate the alveolocapillary membrane.

CONCLUSIONS

Inhalation of GM-CSF seems to be a novel way to positively modulate the alveolar environment toward an altered immunological state, reflected by a positive change in the pattern of surrogate markers, related to better preservation of pulmonary function and thus improved outcomes in CF patients. It is suggested that future studies examining standard endpoint variables such as number of infections and amount of antibiotics used should be supplemented by surrogate markers, to reveal any positive cellular and cytokine responses reflecting changes in the alveolar compartment after GM-CSF inhalation. The immunological alveolar environment should be monitored by a specific pattern of surrogate markers. Continued research is clearly indicated and the role of inhaled GM-CSF in modulating pulmonary host defense in CF patients should be investigated in a large study.

Season of birth and risk of atopic disease among children and adolescents

BACKGROUND

Season of birth (SOB) has been regarded as a risk factor for atopy. The aim of this study was to explore the relationship between season of birth (SOB) and later development of atopic disease in children and adolescents.

METHODS

A total of 1,007 randomly selected subjects, 7 to 17 years of age, who were living in urban Copenhagen, Denmark were studied. All participants were interviewed about respiratory symptoms and possible risk factors for atopic disease. Skin test reactivity, serum total immunoglobulin E (IgE), and airway responsiveness were measured using standard techniques.

RESULTS

The overall risk of atopy, as judged by skin test reactivity and serum total IgE, was the same regardless of SOB. On the contrary, asthma was more common in subjects born in the autumn compared with subjects born during the remaining part of the year (12.4% vs. 5.6%), OR = 2.40, 95% CI (1.56-3.94), p < 0.001. This was observed both for atopic asthma OR = 2.41, 95% CI (1.25-4.64), p = 0.007, non-atopic asthma, OR = 2.35, 95% CI (1.14-4.83), p = 0.02, and house dust mite (HDM) sensitive airway hyperresponsiveness, OR = 3.00, 95% CI (1.44-6.24), p = 0.002. Rhinitis and pollen allergy were not significantly related to SOB.

CONCLUSIONS

Atopy itself is independent of season of birth, whereas asthma is more prevalent among subjects born during the autumn. Regarding asthma, these results suggest that the first months of life enclose a period of particular vulnerability towards environmental risk factors, especially exposure to aeroallergens like HDM.

Quality of care in patients with asthma and rhinitis treated by respiratory specialists and primary care physicians: a 3-year randomized and prospective follow-up study

BACKGROUND

Previous studies evaluating asthma care provided by primary care providers and respiratory specialists (RSs) are limited by short observation periods and nonrandomized designs.

OBJECTIVE

To evaluate long-term outcomes in patients with asthma and rhinitis randomly selected to be cared for by RSs or primary care specialists.

METHODS

In a randomized, 3-year, longitudinal study, 472 patients with asthma and allergic rhinitis were cared for by RSs or primary care physicians. Outcome measures, including disease severity, lung function, medication use, compliance, and self-management knowledge, were compared between groups.

RESULTS

Compared with patients followed up by primary care providers, those in the RS group had reduced asthma severity (P = .046), significantly fewer days with asthma symptoms (P < .01), and improved asthma self-management knowledge (P < .01). At baseline, most patients were undertreated. This value was significantly reduced from 74% to 37% in the RS group and from 71% to 57% in the primary care physician group. We found odds ratios of 8.5 (95% confidence interval, 2-43; P < .01) for worsening of asthma and 0.3 (95% confidence interval, 0.1-0.9; P = .04) for asthma improvement when followed up by primary care physicians, which indicates that primary care follow-up increases the risk of worsening of asthma and decreases the chance of improving. Similar results were observed in patients with allergic rhinitis, although the findings were less pronounced.

CONCLUSION

Treatment and follow-up by an RS ensured better quality of care in patients with asthma and rhinitis.

Associations of a novel IL4RA polymorphism, Ala57Thr, in Greenlander Inuit

BACKGROUND

A novel IL4RA polymorphism, Ala57Thr, was identified in Greenlander Inuit.

OBJECTIVE

We sought to determine whether the novel Thr57 allele is population specific and to assess the associations of Ala57Thr and Ile50Val with atopy in 2 Inuit populations.

METHODS

Ala57Thr and Ile50Val were genotyped in 651 Inuit living in Denmark, 1295 Inuit living in Greenland, and 1329 individuals from 7 populations from widely differing global locations. In Inuit the polymorphisms were evaluated for associations with atopy, rhinitis, asthma, and pulmonary function.

RESULTS

Thr57 was in linkage disequilibrium with Ile50 (D' = 1, r(2) = 0.13) and was common (33%) in the Inuit but rare (<0.6%) in all other populations. In Inuit living in Denmark, the Thr57 allele (in a dose-dependent manner) and the Ile50/Thr57 haplotype were associated with lower risk of atopy (P(linear) = .003 and P = .034, respectively), with similar trends observed for atopic rhinitis and atopic asthma. In Inuit living in Greenland, Thr57 was not associated with atopy or atopic diseases, but Ile50 was weakly associated with lower risk of atopy.

CONCLUSION

The novel IL4RA Ala57Thr was common in and population specific to Greenlander Inuit, with Thr57 associated with a lower risk of atopy in those living in Denmark. Hence a full investigation of genotype-phenotype relationships in a given population can only be achieved if each gene is screened for novel polymorphisms in that population.

CLINICAL IMPLICATIONS

Clinical risk attributable to variations in a gene in an ethnic group requires that all variations of the gene are known for that group.

Risk factors for onset of asthma: a 12-year prospective follow-up study

BACKGROUND

Asthma development and prognosis have been studied extensively in at-risk populations, but knowledge of the natural history of asthma in the general population is limited.

OBJECTIVE

To describe the incidence and remission of asthma and its predictors, data from a 12-year follow-up study of a random population sample (n = 291; age range, 7 to 17 years) at enrollment, were analyzed.

METHODS

The sample was examined in 1986 and in 1998. A case history, including data on asthma, allergic diseases, and lifestyle factors, was obtained by questionnaire and interview. Airway hyperresponsiveness (AHR) to histamine, lung function, and skin-prick test reactivity to a standard panel of 10 aeroallergens were measured.

RESULTS

The point prevalence of asthma increased from 4.1% at the first survey to 11.7% at follow-up, at which point 19.6% of the sample had ever experienced asthma symptoms. Of the subjects with ever-asthma, 40% had remitted at follow-up. Asthma developed in 45 subjects (16.1%) during the follow-up period, which was predicted by the following factors: wheezing in childhood (odds ratio [OR], 3.61; 95% confidence interval [CI], 1.34 to 9.75), AHR (OR, 4.94; 95% CI, 2.42 to 10.08), allergic sensitization to house dust mites (OR, 3.23; 95% CI, 1.00 to 10.40), and dermatitis (OR, 2.94; 95% CI, 1.22 to 7.11). The simultaneous presence of more than one of these risk factors was associated with a high probability of developing asthma at follow-up (61.5%). In subjects without any risk factors, such as AHR, allergic sensitization, rhinitis, dermatitis or wheezing in childhood; paternal/maternal allergy, or asthma, asthma developed in only 4% during follow-up.

CONCLUSION

The presence of AHR and concomitant atopic manifestations in childhood increase the risk of developing asthma in adulthood, and should be recognized as markers of prognostic significance, whereas the absence of these manifestations predicts a very low risk of future asthma.

Unawareness and undertreatment of asthma and allergic rhinitis in a general population

The aim of this study was to determine the extent of unawareness and undertreatment of asthma and allergic rhinitis in an adolescent and adult population in Copenhagen, Denmark.

METHODS

Patients with asthma and rhinitis were recruited by a standardised asthma and rhinitis screening questionnaire. Out of a random sample of 10,877 subjects aged 14-44 years, 1149 subjects were treated or reported symptoms of asthma or rhinitis and agreed to participate. Those subjects were assessed on history, lung function tests, and skin prick tests. Disease severity and optimal treatment were decided according to the GINA and ARIA guidelines.

RESULTS

A total of 726 participants suffered from asthma and/or allergic rhinitis. Concomitant upper and lower airways disease was found in 47%. Seventy-five per cent were allergic and 44% with a known allergy had been tested previously. Asthma was undiagnosed and untreated in 50% of all the asthmatics. According to the guideline recommendation, 76% of asthmatics were undertreated. Rhinitis was undiagnosed in 32% of patients and 83% with moderate to severe rhinitis were undertreated. Patient knowledge about self-care and education was low.

CONCLUSIONS

In this population a large proportion of patients were unaware of having asthma or rhinitis. The pharmaceutical treatment and management practice were inadequate. Our study emphasises the need for additional intervention.

Chronic mucus hypersecretion: a marker of asthma in young adults?

OBJECTIVE

To investigate if chronic mucus hypersecretion (CMH) can be used as a marker of asthma in young adults.

STUDY DESIGN AND SETTING

Cross-sectional study of a population sample of young Danish adults (n=624, 279 males), aged 19-29 years. Case history, including tobacco exposure and respiratory symptoms, was obtained by questionnaire. Pulmonary function, histamine responsiveness, bronchodilator reversibility, skin test reactivity, and leukocyte count were measured using standard techniques.

RESULTS

The overall prevalence of CMH was 7.7%, 8.4% in females and 6.9% in males, respectively, of whom more than 70% were current smokers. The presence of CMH was significantly associated with self-reported asthma, dyspnea at exertion, number of pack-years, lower FEV1/FVC ratio, and lower BMI. However, no significant association was found between CMH and the following asthma-related factors: airway responsiveness to inhaled histamine, bronchodilator reversibility, self-reported rhinitis or eczema, atopy, FEV1 (%pred), and B-eosinophil count.

CONCLUSIONS

CMH is a common finding in young adults, primarily in smokers. CMH was related to respiratory symptoms suggesting asthma, but no significant association was observed between CMH and objective signs of asthmatic airway lability. The present findings therefore may suggest that CMH is likely to be an early marker of smoking-related lung disease in young adults, instead of a marker of reversible obstructive lung disease, which may have important implications for the approach to young people presenting with respiratory symptoms suggesting asthma.

Association between asthma-related phenotypes and the CC16 A38G polymorphism in an unselected population of young adult Danes

The gene for Clara cell 16-kDa (CC16) protein is a promising candidate for asthma susceptibility. The CC16 38A allele has been associated with decreased CC16 plasma levels and increased incidence of asthma in Australian children. To date these results have not been replicated in adults. Therefore, potential links between CC16 A38G, asthma and atopy were investigated in an unselected population of young adult Danes. Four hundred sixty-four Danes, aged 19-29 years, from Copenhagen participated in an asthma and allergy phenotype-genotype study. Genotyping was done by Sau96I restriction digestion of PCR products spanning the A38G polymorphism. Potential A38G genotype and asthma-related phenotype associations were investigated using regression analysis, adjusting for potential confounders where appropriate. Adults with the 38AA genotype had higher odds of current asthma (OR 3.2, P=0.013) and ever asthma (OR 2.2, P=0.045) compared with those with the 38GG genotype. Adjusting for atopy had minimal effect on this relationship. A positive linear trend was evident between the 38A allele and atopic dermatitis (OR 1.67, P=0.02). No associations were found between the A38G polymorphism and rhinitis, atopy, forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC), airway responsiveness (AR) to histamine or peripheral blood eosinophil level (PBEL). An atopy-independent association between CC16 38AA and asthma prevalence was identified, suggesting the CC16 38A allele predisposes to adult asthma independent of Th1/Th2 processes. This finding is consistent with previous studies in children, but is the first reported association between CC16 A38G and asthma in adults. CC16 38A also displayed a positive linear trend with atopic dermatitis.

Respiratory symptoms in greenlanders living in Greenland and Denmark: a population-based study

BACKGROUND

Knowledge of respiratory diseases in an arctic population with increasingly westernized lifestyles provides the opportunity to obtain new information in this field.

OBJECTIVE

To investigate the influence of environment and lifestyle on the presence of respiratory symptoms in a genetically homogenous population sample living under widely differing conditions.

METHODS

Greenland is a part of Denmark, but its climate is mainly arctic, as opposed to the temperate climate of southern Denmark. A random sample of Inuits who had immigrated to Denmark and Inuits from 3 towns and 4 remote settlements in Greenland were studied. Of the 6,695 invited Inuits, 4,162 (62%) completed a questionnaire concerning respiratory symptoms and risk factors.

RESULTS

Of the 4,162 Inuits, 847 (20%) had respiratory symptoms. Bronchitis was more frequent in the areas of Greenland than in Denmark (26% and 20% vs 13%; P < .001), whereas the pattern of asthma was contradictory (6% and 9% vs 10%; P = .057). Bronchitis was associated with living area (P = .01), tobacco consumption (P < .001), and asthma (P = .001), whereas asthma was related to living area (P = .03), hay fever (P < .001), low intake of whale (P = .04), years in Denmark (P = .09), and bronchitis (P < .001).

CONCLUSIONS

Inuits' prevalence of bronchitis and asthma differed, with a higher frequency of bronchitis and a lower frequency of asthma in Inuits living in Greenland compared with Denmark. Living conditions or areas, diet, tobacco use, climate, and atopy are important for the presence of symptoms.

In vitro diagnostic evaluation of patients with inhalant allergies: summary of probability outcomes comparing results of CLA- and CAP-specific immunoglobulin E test systems

For the diagnosis of allergy, presence of allergen-specific immunoglobulin E (IgE) usually is established either by allergen skin tests or by in vitro allergen-specific IgE measurements. However, in vitro assays of specific IgE often are modified as manufacturers improve allergens or change reagents to optimize test performance, affecting the diagnostic performance of in vitro allergen-specific IgE assays. This investigation compares the diagnostic outcomes of the Hitachi Chemical Diagnostics chemiluminescent assay (CLA) and Pharmacia, capsulated hydrophilic carrier polymer (CAP) in vitro allergen-specific IgE test methods in patients with inhalant allergy to a panel of selected allergens. Sera were obtained from 60 consecutive patients who had a clinical history suggesting inhalant allergy and were evaluated by allergen skin-prick test (SPT). Only patients with clinical findings of allergic asthma or rhinoconjunctivitis were included. Sera from patients with at least one positive SPT, which clinically correlated with the case history, were used for specific IgE measurements. Sensitivity and specificity were defined as conditional probabilities describing performances of the CAP system and the CLA system in reference to a standard composed of a combination of allergen-specific symptoms and a positive SPT. A test concordance of 79% was found between the CLA and CAP test results with a correlation coefficient of 0.8. Allergen-specific IgE assay sensitivity of the CLA and CAP systems was similar and allergen dependent, ranging from 67 to 100%. Assay specificity ranged from 39 to 86% for the CLA system and from 36 to 81% for the CAP system. When comparing the specific IgE results with allergen SPTs, 75% (+/- 3%) of CLApositive patients had a positive SPT, and 92% (+/- 4%) of CAPpositive patients had a positive SPT. Eighty-four percent (+/- 4%) of CLAnegative patients had a negative SPT, whereas 69% (+/- 5%) of CAPnegative patients had a negative SPT. The overall concordance between skin tests and in vitro tests was 76% for CLA and 67% for CAP. CLA and CAP score values showed good correlation and both tests may be useful when skin tests cannot be performed to identify subjects with IgE-mediated allergy. The CLA and CAP assays for allergen-specific IgE may be useful as part of an initial allergy evaluation because of the high negative predictive value of negative test results. For the majority of allergens the sensitivity was high. However, the specificity of both in vitro tests was low, indicating that positive in vitro test results should be evaluated carefully in conjunction with clinical symptoms and allergen-specific skin tests to determine the clinical relevance of the allergen sensitization.

Factors associated with asthma in young Danish adults

BACKGROUND

The prevalence of asthma appears to be increasing, but our knowledge about factors associated with asthma in young adults is limited. Factors associated with asthma were studied in 624 (66% of those invited) young Danish adults (aged 19 to 29 years).

OBJECTIVE

The purpose of this study was to investigate the prevalence and predictors of asthma in young Danish adults.

METHODS

Case history, including respiratory symptoms, smoking habits, education, and employment, was obtained by interview, and a questionnaire and was used to evaluate the presence or absence of asthma. Pulmonary function, beta2-reversibility, airway responsiveness to histamine, and blood eosinophil count were measured using standard techniques.

RESULTS

The lifetime prevalence of asthma in these young Danish adults was 17%, and the prevalence of current asthma was 9%. The proportion of current smokers was disturbingly high, 41%, and, further, the proportion of current smokers was significantly higher among those with asthma than among those without asthma (52% and 38%, respectively; P < 0.01). Asthma was significantly associated with current smoking, with lower than predicted forced expiratory volume in 1 second, with lower than predicted ratio of forced expiratory volume in 1 second/forced vital capacity, atopy, higher eosinophil count, and higher degree of airway responsiveness to histamine. The proportion of subjects with no education after junior high school was higher among those with asthma than among those without asthma (P < 0.05). Further, 16 of the 103 (16%) people with asthma had work-related worsening of their respiratory symptoms.

CONCLUSIONS

The presence of current asthma was predicted by current smoking, lower level of lung function, less education, higher blood eosinophil count, and more pronounced airway responsiveness. Further, the proportion of current smokers was higher among asthmatic subjects than among nonasthmatic subjects. Greater efforts must be made to encourage young people with asthma not to smoke.

Prevalence and predictors of atopy among young Danish adults

BACKGROUND

The prevalence of atopic diseases is increasing in western countries, and environmental exposures in childhood may influence development of atopic sensitization.

OBJECTIVE

To investigate the prevalence and predictors of atopy among young Danish adults.

METHODS

Of 940 invited subjects, aged 19-29 years, complete data were obtained from 525 (56%) subjects. All completed a questionnaire concerning asthma, rhinitis, preschool nursery care, smoking habits, family size, education and employment. A skin prick test was performed, and pulmonary function was measured using standard techniques. Atopy was defined as a positive skin prick test.

RESULTS

The frequency of atopy was 32% (males 43% vs. females 23%, P < 0.001). We found a positive association between atopy and atopic dermatitis (P < 0.05), rhinitis (P < 0.001), itching when eating nuts (P < 0.001) and current asthma (P < 0.001). There was an inverse relation between atopy and having furred pets in childhood (P < 0.05), passive smoking in childhood (P < 0.01) and current passive smoking (P < 0.05). An increasing number of siblings was inversely related to atopy to grass (P < 0.05); however, only an increasing number of older siblings seemed to protect from atopy to grass (P < 0.05). Subjects who had never attended a day-care centre had significantly more atopy to grass (P < 0.05). No significant association was found between atopy and airway infections requiring hospitalization before the age of 5 years, or between atopy and bedroom sharing in childhood.

CONCLUSION

Atopy is common among young Danish adults, especially in males. Participants were less likely to be atopic, especially to grass allergen, if they came from large families, had kept furred pets as children, and had been exposed to tobacco smoke.