Temporal trends of aeroallergen sensitization over twenty-five years

BACKGROUND: Little is known about time trends of allergic respiratory disease in adults, in particular in older adults. Furthermore, few trend studies have used objective measurements of IgE sensitization against inhalant allergens. OBJECTIVES: To investigate time trends of aeroallergen sensitization in adults over a 25-year period. METHODS: The study includes a total of 7820 persons, aged 30, 40, 50, and 60 years, who participated in three repeated cross-sectional studies of the general population of Copenhagen, Denmark, in 1976-1977, 1982-1984, and 1999-2001, respectively. Respiratory allergy was assessed by determination of specific IgE aeroallergen sensitization in stored serum samples. RESULTS: Over this 25-year period, a marked and statistically significant increase in the prevalence of aeroallergen sensitization had occurred. This increase was seen in all age-groups challenging the notion that the allergy epidemic only affects generations born 1960 onwards. For example, in 40-year-olds the prevalence (with 95% confidence intervals) of aeroallergen sensitization was 14.9% (12.7-17.1), 19.7% (17.1-22.3), and 27.6% (25.1-30.1) in 1976-1977, 1982-1984, and 1999-2001, respectively. CONCLUSIONS: Our results support that the allergy epidemic has spread to older adults resulting in a continuing increase in the overall prevalence of aeroallergen sensitization and an increase in the mean age of allergic patients.     

Association between alcohol consumption and aeroallergen sensitization in Danish adults

BACKGROUND: It has been proposed that alcohol consumption may be one of the lifestyle factors associated with a westernized, urban, and affluent lifestyle contributing to the rise in atopic disease. OBJECTIVE: The aim was to investigate the association between alcohol consumption and atopy (aeroallergen sensitization). METHODS: In 1982, a population-based cross-sectional study of 3608 Danes (79% of the invited), aged 30, 40, 50, and 60 years, was carried out. Information on alcohol consumption was obtained by a questionnaire. Aeroallergen sensitization was defined as a positive test for the detection of specific IgE against a panel of 19 common inhalant allergens in stored serum samples. A total of 3317 subjects with complete information on all variables were included in the analyses. RESULTS: We found a statistically significant association between alcohol consumption and aeroallergen sensitization (independent of the type of alcoholic drink consumed). This association appeared to relate only to those who consumed more than 8 drinks/week. After adjustment for confounders this association was only statistically significant for those who consumed 15-21 drinks/week (adjusted odds ratio 1.8, 95% confidence interval 1.2-2.8). CONCLUSION: In this adult general population, self-reported alcohol consumption was positively associated with aeroallergen sensitization.     

Repeated latex aeroallergen challenges employing a hooded exposure chamber: safety and reproducibility

BACKGROUND: Bronchial, nasal, and conjunctival challenges are useful for clarifying discordant clinical history (Hx) and skin and/or serologic tests and in assessing semiquantitative changes in biologic sensitivity over time. The objective of this study was to determine the safety and reproducibility of repeated latex-allergen challenges with a hooded exposure chamber (HEC). METHODS: The HEC system comprises a powered forced-air respirator with a fitted face shield and hood that uses glove-derived latex-allergen associated cornstarch particles (LAC) to expose simultaneously the conjunctiva, nose, and lungs. Serial control and incremental LAC challenges are conducted until an endpoint based on upper and/or lower respiratory tract symptoms and peak expiratory flow rates is reached. Six latex-allergic (Hx and puncture skin test [PST]- and 5/6 radioallergosorbent test [RAST]-positive) subjects were challenged on three separate occasions at least 2 weeks apart. Serial latex PST midpoints and serum anti-latex IgE by RAST were monitored at each visit and at a fourth follow-up visit. RESULTS: All subjects responded to LAC, but not to air or control cornstarch administered as controls. All responses were confined to mild symptoms of allergic rhinoconjunctivitis and/or asthma that either resolved spontaneously or were reversed with inhaled albuterol. No subject experienced a systemic or delayed reaction. There were no significant changes in the endpoint LAC doses over the three challenge visits (P>0.2). The mean coefficient of variation for log2 endpoints within-subjects was 17.3+/-17.2% (SD). The serum latex-specific IgE was not significantly boosted by the three challenges (P>0.2). The concentration of latex extract necessary to produce an 8-mm wheal by PST was not significantly changed during the study (P>0.1), indicating that latex sensitivity was not affected by the repeated LAC exposures. CONCLUSIONS: The results of this study indicate that repeated HEC latex-allergen challenges are both reproducible and safe, and do not increase latex sensitivity.     

Association between obesity and asthma in a twin cohort

BACKGROUND: Obesity is linked to asthma in a yet poorly understood manner. We examined the relationship between obesity and asthma in a population-based sample of twins. METHODS: From the cohorts born between 1953 and 1982, who were enrolled in The Danish Twin Registry, a total of 29 183 twin individuals participated in a nationwide questionnaire study, where data on height, weight and asthma were collected. Latent factor models of genetic and environmental effects were fitted using maximum likelihood methods. RESULTS: The age-adjusted risk of asthma was increased both in obese females, OR = 1.96 (1.45-2.64), P < or = 0.001 and in obese males, OR = 1.59 (1.08-2.33), P = 0.02. According to best-fitting models, the heritability for obesity was 81% in males and 92% in females, whereas the heritability for asthma was 78% and 68% in males and females respectively. The age-adjusted genetic liabilities to obesity and asthma were significantly correlated only in females, r = 0.28 (0.16-0.38). CONCLUSIONs: Obese subjects have an increased risk for asthma, which in females seems partly because of common genes.     

The impact of obesity and insulin resistance on the outcome of IVF or ICSI in women with polycystic ovarian syndrome

The impact of insulin resistance on the outcome of IVF or intracytoplasmic sperm injection (ICSI) in women with polycystic ovarian syndrome (PCOS) was examined. Insulin sensitivity was measured by the continuous infusion of glucose with model assessment (CIGMA) test. Insulin-resistant (n = 26) and non-insulin-resistant women (n = 30) with PCOS underwent a total of 100 cycles of long-term down-regulation with buserelin acetate, stimulation with human recombinant FSH, and IVF or ICSI. Blood samples were taken throughout ovarian stimulation for hormone assays. Insulin-resistant and non-insulin-resistant women had similar concentrations of FSH, LH, testosterone and androstenedione throughout stimulation, but insulin-resistant women had hyperinsulinaemia and lower sex hormone binding globulin concentrations. Insulin-resistant women also had lower oestradiol concentrations during stimulation and required higher FSH doses, but these differences disappeared after controlling for the higher body weight in the group of insulin-resistant women. Groups had similar number of oocytes collected, similar implantation and pregnancy rates, and the incidence of ovarian hyperstimulation syndrome was also similar. Obesity, independent of hyperinsulinaemia, was related to a lower oocyte count and increased FSH requirement. It is concluded that in PCOS women receiving long-term down-regulation and stimulation with recombinant FSH, insulin resistance is neither related to hormone levels nor to IVF outcome. Obesity, independent of insulin resistance, is associated with relative gonadotrophin resistance.     

Epicutaneous aeroallergen sensitization in atopic dermatitis infants - determining the role of epidermal barrier impairment

Background:  Sensitization to atopens is an early phenomenon that overlaps with the onset of atopic dermatitis (AD) in infancy. Early epidermal barrier impairment may facilitate the epicutaneous penetration of atopens.
Objective:  To correlate transepidermal water loss (TEWL) and aeroallergen sensitization in infants with AD.
Methods:  In this cross-sectional study we enrolled 59 AD children and 30 controls aged 3–12 months. Transepidermal water loss in uninvolved skin, specific immunoglobulin E, atopy patch test (APT) and skin prick tests were performed with respect to seven aeroallergens, i.e., Dermatophagoides pteronyssinus , D. farinae , cat, dog, birch pollen, ambrosia, and cockroach. Environmental conditions were assessed by a questionnaire, and the house dust mite (HDM) concentration was determined in dust samples.
Results:  Eighty-nine percent of AD infants had a positive APT vs one out of eleven controls. AD infants had a significantly higher mean TEWL than controls (27.4 vs 11.1 g/m²/h, P  < 0001). Children with two or more positive APT had higher TEWL than the others (31.1 vs 19.0 g/m²/h, P  < 0.025). No correlation was found between indoor APT results and exposure to HDM, cats, and dogs at home.
Conclusions:  This study confirms the high prevalence of delayed sensitization to indoor and outdoor aeroallergens in AD infants, and shows that the higher the TEWL, the higher the prevalence of sensitization to aeroallergens. These data are in favor of a major role of a constitutive epidermal barrier impairment in determining early atopen sensitization in infants with AD.     

Anaphylaxis to subcutaneous neutral protamine Hagedorn insulin with simultaneous sensitization to protamine and insulin

We report an insulin-treated diabetic patient who suffered, in a 2-month period, three severe anaphylactic reactions immediately after self-administered subcutaneous injections of neutral protamine Hagedorn (NPH) human recombinant-DNA insulin. These reactions consisted of local and systemic symptoms, including dyspnea and hypotension. A simultaneous sensitization to human insulin and to protamine was demonstrated, both by skin tests and by the determination of serum specific IgE. Suspecting protamine allergy, we performed a test dose to human lente insulin with perfect tolerance. After a 1-year follow-up with lente-insulin treatment, no reactions have occurred, despite treatment interruptions. Therefore, protamine IgE-mediated allergy probably caused our patient's reactions. In conclusion, protamine sensitization should be ruled out in any patient with a history of reactions to subcutaneous protamine-containing insulins, even if insulin sensitization is present.     

Comparison of skin prick tests with specific serum immunoglobulin E in the diagnosis of fungal sensitization in patients with severe asthma

Background It has been shown that patients with allergic bronchopulmonary aspergillosis (ABPA) and patients with severe asthma with fungal sensitization (SAFS) can benefit from antifungal therapy. It is not known whether allergy skin prick tests (SPT) or specific IgE tests are more sensitive in the identification of patients who are sensitized to fungi and who are therefore candidates for antifungal therapy.
Objectives To compare SPT and specific serum IgE tests for fungal sensitization in patients with severe asthma.
Methods We have undertaken SPT and specific serum IgE tests to six fungi ( Aspergillus fumigatus, Candida albicans, Penicillium notatum, Cladosporium herbarum, Alternaria alternata and Botrytis cineria ) and specific serum IgE test for Trichophyton in 121 patients with severe asthma (British Thoracic Society/SIGN steps 4 and 5).
Results Sixty-six percent of patients were sensitized to one or more fungi based on SPT and/or specific serum IgE results. Positivity to SPT and/or specific serum IgE was as follows: A. fumigatus 45%, C. albicans 36%, P. notatum 29%, C. herbarum 24%, A. alternata 22%, B. cineria 18%, Trichophyton 17% (specific serum IgE only). Concordance between the tests was 77% overall but only 14–56% for individual fungi. Twenty-nine (24%) patients were sensitized to a single fungus and seven (6%) were sensitized to all seven fungal species. Fifty percent of patients were sensitized to fungal and non-fungal extracts, 21% were sensitized only to non-fungal extracts, 16% were sensitized only to fungal extracts and 13% had no positive tests.
Conclusion This study is consistent with previous reports that fungal sensitization is common in patients with severe asthma. At present, it remains necessary to undertake both SPT and specific serum IgE testing to identify all cases of fungal sensitization. This may be important in the identification of patients with ABPA and SAFS who may benefit from antifungal therapy.     

Acoustic perception of high-pitch tones by patients with bronchial asthma

A regular and marked increase of hearing acuity at frequencies of 12, 16, and 20 kHz, by both air and bone conduction, is found in patients with bronchial asthma.Laboratory of Pathophysiology and Acoustics, Moscow Research Institute of the Ear, Throat, and Nose, Ministry of Health of the RSFSR. Department of Pulmonology, S. P. Botkin Hospital, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 9, pp. 1050–1051, September, 1976.     

脂肪组织巨噬细胞与胰岛素抵抗关系的研究进展

脂肪组织除了能够储存能量,还能过度分泌各种细胞因子,促使巨噬细胞大量募集,而募集的巨噬细胞进一步分泌各种炎性因子作用于脂肪细胞,二者互相作用导致慢性炎症发生。肥胖相关的脂肪细胞肥大、慢性炎性状态以及脂肪组织异常分化是导致胰岛素抵抗的重要原因。巨噬细胞大量浸润脂肪组织是脂肪组织慢性炎性反应的重要标志。     

Interactive effects of adiposity and insulin resistance on the impaired lung function in asthmatic adults: cross-sectional analysis of NHANES data

Background: Obesity is considered a risk factor for both asthma and insulin resistance in adults. Insulin resistance (IR) also influences pulmonary function in the non-obese population.

Aim: To investigate the modifying effect of insulin resistance on the predictive role of anthropometric measures in the estimation of impaired lung function among asthmatic adults.

Subjects and methods: A cross-sectional study of 1276 adults extracted from the NHANES 2009–2012 database was performed. Adjusted multiple linear regression was conducted to analyse the contributory role of obesity and IR in predicting lung function among asthmatic adults.

Results: BMI, waist circumference (WC) and waist-to-height ratio (WHtR) showed significantly negative correlations with FVC (r=–0.24, –0.18, –0.39, respectively; p?<?0.001), FEV1(r=–0.24, –0.21, –0.40, respectively; p?<?0.001) and FEF 25–75% (r=–0.15, –0.18, –0.27, respectively; p?<?0.001). Even after adjustment for the covariates (age, gender, smoking history and standing height), BMI and HOMA-IR had significant relationships with FVC (β=??10.3; p?<?0.01 and β=??16.0; p?<?0.05) and FEV1 (β=??8.7; p?<?0.01 and β=??11.7; p?<?0.05). BMI could significantly predict the decreased FVC (β=??13.7; p?<?0.01) and FEV1 (β=??10.7; p?<?0.01) only in the insulin resistant asthmatics.

Conclusion: WHtR and IR predict impaired lung function in overweight/obese asthmatic adults independently. IR also modifies the association between excessive adiposity and respiratory function in asthmatic adults.     

Insulin resistance as a predictor of incident asthma‐like symptoms in adults

Background There is accumulating evidence that obesity is associated with an increased risk of asthma. It has been hypothesized that insulin resistance may be involved in obesity‐induced asthma, but till date there is no prospective data on this issue. Objective To investigate the association of obesity and insulin resistance with the incidence of asthma‐like symptoms in adults. Methods Out of a random sample of 12 934 persons from a general population, 6784 (52.5%) were included and participated in a health examination in 1999–2001. After 5 years they were re‐invited and 4516 (66.6%) participated at follow‐up. At baseline three obesity measures were considered: body mass index, waist circumference, and waist‐to‐hip ratio. In addition, fasting glucose and insulin were measured for determination of insulin resistance. Information on asthma‐like symptoms at baseline and follow‐up were obtained by questionnaires. A total of 3441 participants defined as non‐asthmatic at baseline and with complete information on all the considered variables were included in the analyses. Data were controlled for confounding by sex, age, social status, and smoking. Results All obesity measures were associated with incident wheezing and asthma‐like symptoms. In addition, insulin resistance was associated with incident wheezing [odds ratio (OR) 1.87, 95% confidence interval (CI) 1.38–2.54] and asthma‐like symptoms (OR 1.61, 95% CI 1.23–2.10). The effect of insulin resistance was stronger than that of obesity and was independent of sex. Conclusion We found that insulin resistance was associated with an increased risk of developing asthma‐like symptoms. This finding supports the hypothesis that obesity and asthma may be linked through inflammatory pathways also involved in insulin resistance.     

Association of prostaglandin-endoperoxide synthase 2 gene polymorphisms with asthma and atopy in Chinese children

BACKGROUND: Cyclooxygenase-2 (COX-2) plays essential roles in inflammation. Previous studies have suggested associations between prostaglandin-endoperoxide synthase 2 (PTGS2) polymorphisms and prostaglandins production in asthma. OBJECTIVE: We have investigated the effects of Chinese tagging single nucleotide polymorphisms (SNPs) of PTGS2 on asthma traits in 299 Chinese asthmatic children and 175 controls. METHODS: Plasma total and allergen-specific IgE were measured by enzyme immunoassay. PTGS2.8473T-->C in the 3'-untranslated region of exon 10 and three tag SNPs covering most of the variations in PTGS2 haplotypes in Chinese were genotyped by restriction fragment length polymorphism. RESULTS: Among the four SNPs, only PTGS2.8473 showed significant association with asthma (P = 0.034) and atopy (P = 0.005 when compared with non-atopic controls; P = 0.023 with all controls). Carriers of the C allele had a 1.5-fold (95% confidence interval: 1.01-2.30) risk of developing asthma than those homozygous for the T allele. Multivariate regression revealed significant correlations between PTGS2.8473 and forced expiratory volume in 1 s (FEV(1); P = 0.002) and peak expiratory flow rate (PEFR; P = 0.001) with age and gender adjusted. Patients with the C allele of PTGS2.8473 had significantly lower FEV(1) (median: 90.0%vs 98.0%; P = 0.0047) and PEFR (70.0%vs 73.5%; P = 0.0065) than those homozygous for the T allele. No significant association between plasma total and allergen-specific IgE and these SNPs or with their haplotypes was found. CONCLUSIONS: PTGS2.8473 polymorphism is associated with asthma, atopy and lung function but not plasma IgE in Chinese children. This may help to explore the pharmacogenetics of COX-2 inhibitors.