Herman Mitchell

University of North Carolina at Chapel Hill, North Carolina, United States

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Publications (88)721.9 Total impact

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    ABSTRACT: Background Allergic sensitization is an important risk factor for the development of atopic disease. The National Health and Nutrition Examination Survey (NHANES) 2005-2006 provides the most comprehensive information on IgE-mediated sensitization in the general US population. Objective We investigated clustering, sociodemographic, and regional patterns of allergic sensitization and examined risk factors associated with IgE-mediated sensitization. Methods Data for this cross-sectional analysis were obtained from NHANES 2005-2006. Participants aged 1 year or older (n = 9440) were tested for serum specific IgEs (sIgEs) to inhalant and food allergens; participants 6 years or older were tested for 19 sIgEs, and children aged 1 to 5 years were tested for 9 sIgEs. Serum samples were analyzed by using the ImmunoCAP System. Information on demographics and participants' characteristics was collected by means of questionnaire. Results Of the study population aged 6 years and older, 44.6% had detectable sIgEs, whereas 36.2% of children aged 1 to 5 years were sensitized to 1 or more allergens. Allergen-specific IgEs clustered into 7 groups that might have largely reflected biological cross-reactivity. Although sensitization to individual allergens and allergen types showed regional variation, the overall prevalence of sensitization did not differ across census regions, except in early childhood. In multivariate modeling young age, male sex, non-Hispanic black race/ethnicity, geographic location (census region), and reported pet avoidance measures were most consistently associated with IgE-mediated sensitization. Conclusions The overall prevalence of allergic sensitization does not vary across US census regions, except in early life, although allergen-specific sensitization differs based on sociodemographic and regional factors. Biological cross-reactivity might be an important but not the sole contributor to the clustering of allergen-specific IgEs.
    The Journal of allergy and clinical immunology 08/2014; · 12.05 Impact Factor
  • S J Arbes, A Calatroni, H E Mitchell, P J Gergen
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    ABSTRACT: Atopy is an established risk factor for asthma, and an elevated eosinophil level is a hallmark of atopic and non-atopic asthma. Whether atopy and eosinophils act independently or interact to influence asthma has clinical and public health implications. To investigate the relationship between atopy and eosinophils in asthma. Data on current asthma, atopy (IgE positive to ≥ 1 allergen), and blood eosinophil percent (dichotomized at the median) were obtained for persons aged ≥ 6 years from the National Health and Nutrition Examination Survey 2005-2006. Interaction on an additive scale was evaluated by estimating the prevalences of asthma for combinations of atopy (yes or no) and eosinophil percent (high or low) and calculating the excess prevalence due to interaction. For all ages combined, the adjusted prevalences of asthma were 4.6%, 7.6%, 6.9% and 17.2% for persons with neither factor, atopy alone, a high eosinophil percent alone and both factors respectively. The excess prevalence of asthma due to interaction was 7.2%, indicating synergism. The excess prevalence was greatest in children aged 6-17 years (15.3%), and it decreased with each older age category until it was absent in adults aged ≥ 55 years (-0.2%). In children, 94% of asthma cases attributable to the 2 factors were attributable to the interaction, whereas in the oldest adults, no cases were attributable to the interaction. Interaction between atopy and an elevated eosinophil level in asthma cases was very strong in children but absent in the oldest adults, which suggests different mechanistic pathways for these factors by age and supports the notion that asthma is a heterogeneous disease. In addition, the age-dependent interaction between the factors has potential implications for the selection of asthma patients for treatments that would target either IgE or a high eosinophil level.
    Clinical & Experimental Allergy 05/2013; 43(5):544-51. · 4.32 Impact Factor
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    ABSTRACT: BACKGROUND: Decreased 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with an increased prevalence and severity of asthma and a lower response to inhaled corticosteroids. OBJECTIVE: The objective was to determine the association between serum 25(OH)D concentrations and asthma prevalence, severity, and response to asthma treatment. DESIGN: Secondary analyses were conducted in 2 samples of adolescents 12-20 y of age: 1) NHANES 2001-2006 (n = 6487), a cross-sectional nationally representative sample of the US population, and 2) a cohort of inner-city adolescents with asthma managed prospectively for 46 wk with guidelines-based therapy in the Asthma Control Evaluation (ACE; n = 226) trial. RESULTS: Mean (±SD) serum 25(OH)D concentrations in the NHANES and ACE samples were lower in African Americans than in non-African Americans (NHANES: 14.9 ± 6.5 compared with 23.0 ± 8.4 ng/mL, P < 0.0001; ACE: 11.2 ± 6.9 compared with 15.8 ± 7.1 ng/mL, P < 0.0001). In the NHANES sample, mean concentrations did not differ between participants without and with asthma (African Americans: 14.9 ± 6.4 compared with 15.0 ± 6.6 ng/mL, respectively, P = 0.87; non-African Americans: 23.0 ± 8.5 compared with 23.6 ± 8.2 ng/mL, respectively, P = 0.16). In the ACE models that used either a predefined cutoff (<20 ng/mL) or linear regression, 25(OH)D concentrations showed either no relation or minor contradictory correlations with indicators of asthma severity, treatment requirements, spirometry, or atopy/inflammation. CONCLUSION: In 2 samples of adolescents, overall serum 25(OH)D concentrations were low and were not consistently associated with the presence of asthma, multiple asthma characteristics, asthma morbidity, or response to treatment. The ACE trial was registered at clinicaltrials.gov as NCT0011441.
    American Journal of Clinical Nutrition 04/2013; · 6.50 Impact Factor
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    ABSTRACT: Treatment regimens for omalizumab are guided by a dosing table that is based on total serum IgE and body weight. Limited data exist about onset and offset of omalizumab efficacy in children and adolescents or subgroups that most benefit from treatment. Post hoc analyses were conducted to (1) examine patient characteristics of those eligible and ineligible for omalizumab, (2) describe onset of effect after initiation of omalizumab and offset of treatment effect after stopping therapy, and (3) determine whether the efficacy differs by age, asthma severity, dosing regimen, and prespecified biomarkers. Inner-city children and adolescents with persistent allergic asthma were enrolled in the Inner-City Anti-IgE Therapy for Asthma trial that compared omalizumab with placebo added to guidelines-based therapy for 60 weeks. Two hundred ninety-three of 889 participants (33%) clinically suitable for omalizumab were ineligible for dosing according to a modified dosing table specifying IgE level and body weight criteria. Baseline symptoms were comparable among those eligible and ineligible to receive omalizumab, but other characteristics (rate of health care utilization and skin test results) differed. The time of onset of omalizumab effect was <30 days and time of offset was between 30 and 120 days. No difference in efficacy was noted by age or asthma severity, but high exhaled nitric oxide, blood eosinophils, and body mass index predicted efficacy. A significant portion of children and adolescents particularly suited for omalizumab because of asthma severity status may be ineligible due to IgE >1300 IU/mL. Omalizumab reduced asthma symptoms and exacerbations rapidly; features associated with efficacy can be identified to guide patient selection.
    The journal of allergy and clinical immunology. In practice. 03/2013; 1(2):163-71.
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    ABSTRACT: BACKGROUND: Consistent performance of allergen assays is essential to ensure reproducibility of exposure assessments for investigations of asthma and occupational allergic disease. This study evaluated intra- and inter-laboratory reproducibility of a fluorescent multiplex array, which simultaneously measures eight indoor allergens in a single reaction well. METHODS: A multi-center study was performed in nine laboratories in the US and Europe to determine the inter-laboratory variability of an 8-plex array for dust mite, cat, dog, rat, mouse and cockroach allergens. Aliquots of 151 dust extract samples were sent to participating centers and analyzed by each laboratory on three separate occasions. Agreement within and between laboratories was calculated by the concordance correlation coefficient (CCC). RESULTS: Results were obtained for over 32,000 individual allergen measurements. Levels covered a wide range for all allergens from below the lower limit of detection (LLOD=0.1 - 9.8ng/ml) to higher than 6800ng/ml for all allergens except Mus m 1, which was up to 1700ng/ml. Results were reproducible within as well as between laboratories. Within laboratories, 94% of CCC were ≥0.90, and 80% of intra-laboratory results fell within a 10% coefficient of variance (CV%). Results between laboratories also showed highly significant positive correlations for all allergens (~0.95, p<0.001). Overall means of results were comparable, and inter-laboratory CV% for all allergens except Rat n 1 ranged between 17.6% and 26.6%. CONCLUSION: The data indicate that performance criteria for fluorescent multiplex array technology are reproducible within and between laboratories. Multiplex technology provides standardized and consistent allergen measurements that will streamline environmental exposure assessments in allergic disease.
    Journal of immunological methods 10/2012; · 2.35 Impact Factor
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    ABSTRACT: Standardized studies examining environmental microbial exposure in populations at risk for asthma are necessary to improve our understanding of the role this factor plays in disease development. Here we describe studies aimed at developing guidelines for high-resolution culture-independent microbiome profiling, using a phylogenetic microarray (PhyloChip), of house dust samples in a cohort collected as part of the NIH-funded Inner City Asthma Consortium (ICAC). We demonstrate that though extracted DNA concentrations varied across dust samples, the majority produced sufficient 16S rRNA to be profiled by the array. Comparison of array and 454-pyrosequencing performed in parallel on a subset of samples, illustrated that increasingly deeper sequencing efforts validated greater numbers of array-detected taxa. Community composition agreement across samples exhibited a hierarchy in concordance, with the highest level of agreement in replicate array profiles followed by samples collected from adjacent 1×1m(2) sites in the same room, adjacent sites with different sized sampling quadrants (1×1 and 2×2m(2)), different sites within homes (living and bedroom) to lowest in living room samples collected from different homes. The guidelines for sample collection and processing in this pilot study extend beyond PhyloChip based studies of house-associated microbiota, and bear relevance for other microbiome profiling approaches such as next-generation sequencing.
    Journal of microbiological methods 09/2012; 91(2):231-9. · 2.43 Impact Factor
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    ABSTRACT: BACKGROUND: Childhood asthma morbidity and mortality in New Orleans is among the highest in the nation. In August 2005, Hurricane Katrina created an environmental disaster that led to high levels of mold and other allergens and disrupted healthcare for children with asthma. OBJECTIVES: We implemented a unique hybrid asthma counselor and environmental intervention based upon successful NIH asthma interventions from the National Cooperative Inner City Asthma (NCICAS) and Inner-City Asthma (ICAS) Studies with the goal of reducing asthma symptoms in New Orleans children following Hurricane Katrina. METHODS: Children (4-12 years old) with moderate-to-severe asthma (N=182) received asthma counseling and environmental intervention for approximately 1 year. HEAL was evaluated employing several analytical approaches including: a pre-post evaluation of symptom changes over the entire year, an analysis of symptoms according to the timing of asthma counselor contact, and a comparison to previous evidence-based interventions.. RESULTS: Asthma symptoms during the previous 2 weeks decreased from 6.5 days at enrollment to 3.6 days at the 12-month symptom assessment (a 45% reduction, p<0.001), consistent with changes observed after NCICAS and ICAS interventions (35% and 62% reductions in symptom days, respectively). Children whose families had contact with a HEAL asthma counselor by 6 months showed a 4.09-day decrease (95% CI: 3.25 to 4.94-day decrease) in symptom days, compared to a 1.79-day decrease (95% CI: 0.90, 2.67) among those who had not yet seen an asthma counselor (p<0.001). CONCLUSIONS: The novel combination of evidence-based asthma interventions was associated with improved asthma symptoms among children in post-Katrina New Orleans. Post-intervention changes in symptoms were consistent with previous randomized trials of NCICAS and ICAS interventions.
    Environmental Health Perspectives 08/2012; · 7.26 Impact Factor
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    ABSTRACT: BACKGROUND: Rain and flooding from Hurricane Katrina resulted in widespread growth of mold and bacteria and production of allergens in New Orleans, which may have led to increased exposures and morbidity in children with asthma. OBJECTIVES: To characterize post-Katrina exposures to mold and allergens in children with asthma in the Head-off Environmental Asthma in Louisiana (HEAL) study. METHODS: The homes of 182 children with asthma in New Orleans and surrounding parishes were evaluated by visual inspection, temperature and moisture measurements, and air and dust sampling. Air was collected using vacuum-pump spore traps and analyzed for over 30 mold taxa using bright field microscopy. Dust was collected from the children's beds and bedroom floors and analyzed for mouse (Mus m 1), dust mite (Der p 1), cockroach (Bla g 1), and mold (Alternaria mix) allergens using ELISA. RESULTS: Over half (62%) of the children were living in homes that had been water damaged by rain, flooding, or both. Geometric mean indoor and outdoor airborne mold levels were 501 and 3,958 spores/m3, respectively. Alternaria antigen was detected in dust from 98% of homes, with 58% having concentrations >10 µg/g. Mus m 1, Der p 1, and Bla g 1 were detected in 60%, 35%, and 20% of homes, respectively, at low mean concentrations. CONCLUSIONS: Except for Alternaria antigen in dust, concentrations of airborne mold (ratio of indoor to outdoor mold) and dust allergens in the homes of HEAL children were lower than measurements found in other studies, possibly because of extensive post-Katrina mold remediation and renovations, or because children moved into cleaner homes upon returning to New Orleans.
    Environmental Health Perspectives 08/2012; · 7.26 Impact Factor
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    ABSTRACT: BACKGROUND: In the city of New Orleans and surrounding parishes (NO), children with asthma were perilously impacted by Hurricane Katrina from disrupted healthcare, high home mold and allergen levels, and high stress. OBJECTIVES: The Head-off Environmental Asthma in Louisiana (HEAL) study was conducted to examine relationships between the post-Katrina environment and childhood asthma in NO and assess a novel asthma counselor intervention that provided case management and guidance for reducing home mold and allergen levels. METHODS: Children (4-12 years old) with moderate-to-severe asthma were recruited from NO schools. Over 1 year, they received 2 clinical evaluations, 3 home environmental evaluations, and the asthma intervention. Quarterly endpoints included symptom days, medication use, and unscheduled ED or clinic visits. A community advisory group was assembled and informed HEAL at all phases. RESULTS: Children (N=182) were enrolled in HEAL; 67% were African American, and 25% came from households with annual incomes <$15,000. HEAL children were symptomatic, averaging 6.6 symptom days in the 2 weeks before baseline, and had frequent unscheduled visits to clinics or emergency departments (76% had at least 1 unscheduled visit in the preceding 3 months). In this report, we describe study design and baseline characteristics of HEAL children. CONCLUSIONS: Despite numerous challenges faced by investigators, study staff, and participants, including destroyed infrastructure, disrupted lives, and lost jobs, HEAL was successful in terms of recruitment and retention, the high quality of data collected that will provide insight into asthma-allergen relationships, and the asthma intervention. This success was due to using an adaptive approach and refining processes as needed.
    Environmental Health Perspectives 08/2012; · 7.26 Impact Factor
  • American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California; 05/2012
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    ABSTRACT: Respiratory symptoms are commonly used to assess the impact of patient-centered interventions. At the request of National Institutes of Health (NIH) institutes and other federal agencies, an expert group was convened to propose which measurements of asthma symptoms should be used as a standardized measure in future clinical research studies. Asthma symptom instruments were classified as daily diaries (prospectively recording symptoms between research visits) or retrospective questionnaires (completed at research visits). We conducted a systematic search in PubMed and a search for articles that cited key studies describing development of instruments. We classified outcome instruments as either core (required in future studies), supplemental (used according to study aims and standardized), or emerging (requiring validation and standardization). This work was discussed at an NIH-organized workshop in March 2010 and finalized in September 2011. Four instruments (3 daily diaries, 1 for adults and 2 for children; and 1 retrospective questionnaire for adults) were identified. Minimal clinically important differences have not been established for these instruments, and validation studies were only conducted in a limited number of patient populations. Validity of existing instruments may not be generalizable across racial-ethnic or other subgroups. An evaluation of symptoms should be a core asthma outcome measure in clinical research. However, available instruments have limitations that preclude selection of a core instrument. The working group participants propose validation studies in diverse populations, comparisons of diaries versus retrospective questionnaires, and evaluations of symptom assessment alone versus composite scores of asthma control.
    The Journal of allergy and clinical immunology 03/2012; 129(3 Suppl):S124-35. · 12.05 Impact Factor
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    ABSTRACT: Asthma severity is reflected in many aspects of the disease, including impairment and future risks, particularly for exacerbations. According to the Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma, however, to assess more comprehensively the severity of asthma the level of current treatment needed to maintain a level of control should be included. Development and validation of a new instrument, the Composite Asthma Severity Index (CASI), which can quantify disease severity by taking into account impairment, risk, and the amount of medication needed to maintain control. At present, there is no instrument available to measure and assess the multidimensional nature of asthma. Twenty-six established asthma investigators, who are part of the National Institutes of Health-supported Inner City Asthma Consortium, participated in a modified Delphi consensus process to identify and weight the dimensions of asthma. Factor analysis was performed to identify independent domains of asthma by using the Asthma Control Evaluation trial. CASI was validated by using the Inner City Anti-IgE Therapy for Asthma trial. CASI scores include 5 domains: day symptoms and albuterol use, night symptoms and albuterol use, controller treatment, lung function measures, and exacerbations. At Asthma Control Evaluation trial enrollment, CASI ranged from 0 to 17, with a mean of 6.2. CASI was stable, with minimal change in variance after 1 year of treatment. In external validation, CASI detected a 32% larger improvement than did symptoms alone. CASI retained its discriminatory ability even with low levels of symptoms reported after months of guidelines-directed care. Thus, CASI has the ability to determine the level of asthma severity and provide a composite clinical characterization of asthma.
    The Journal of allergy and clinical immunology 03/2012; 129(3):694-701. · 12.05 Impact Factor
  • Journal of Allergy and Clinical Immunology 02/2012; 129(2):AB153. · 11.25 Impact Factor
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    ABSTRACT: Mold and other allergen exposures exacerbate asthma symptoms in sensitized individuals. We evaluated allergen concentrations, skin test sensitivities, and asthma morbidity for 182 children, aged 4-12 years, with moderate to severe asthma, enrolled 18 months after Katrina, from the city of New Orleans and the surrounding parishes that were impacted by the storm, into the Head-off Environmental Asthma in Louisiana (HEAL) observational study. Dust (indoor) and air (indoor and outdoor) samples were collected at baseline of 6 and 12 months. Dust samples were evaluated for dust mite, cockroach, mouse, and Alternaria by immunoassay. Air samples were evaluated for airborne mold spore concentrations. Overall, 89% of the children tested positive to ≥1 indoor allergen, with allergen-specific sensitivities ranging from 18% to 67%. Allergen concentration was associated with skin sensitivity for 1 of 10 environmental triggers analyzed (cat). Asthma symptom days did not differ with skin test sensitivity, and surprisingly, increased symptoms were observed in children whose baseline indoor airborne mold concentrations were below median levels. This association was not observed in follow-up assessments. The lack of relationship among allergen levels (including mold), sensitivities, and asthma symptoms points to the complexity of attempting to assess these associations during rapidly changing social and environmental conditions.
    International Journal of Pediatrics 01/2012; 2012:427358.
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    ABSTRACT: Research has underscored the effects of exposure and sensitization to allergens on the severity of asthma in inner-city children. It has also revealed the limitations of environmental remediation and guidelines-based therapy in achieving greater disease control. We enrolled inner-city children, adolescents, and young adults with persistent asthma in a randomized, double-blind, placebo-controlled, parallel-group trial at multiple centers to assess the effectiveness of omalizumab, as compared with placebo, when added to guidelines-based therapy. The trial was conducted for 60 weeks, and the primary outcome was symptoms of asthma. Among 419 participants who underwent randomization (at which point 73% had moderate or severe disease), omalizumab as compared with placebo significantly reduced the number of days with asthma symptoms, from 1.96 to 1.48 days per 2-week interval, a 24.5% decrease (P<0.001). Similarly, omalizumab significantly reduced the proportion of participants who had one or more exacerbations from 48.8 to 30.3% (P<0.001). Improvements occurred with omalizumab despite reductions in the use of inhaled glucocorticoids and long-acting beta-agonists. When added to a regimen of guidelines-based therapy for inner-city children, adolescents, and young adults, omalizumab further improved asthma control, nearly eliminated seasonal peaks in exacerbations, and reduced the need for other medications to control asthma. (Funded by the National Institute of Allergy and Infectious Diseases and Novartis; ClinicalTrials.gov number, NCT00377572.).
    New England Journal of Medicine 03/2011; 364(11):1005-15. · 54.42 Impact Factor
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    ABSTRACT: Asthma was the most common comorbidity of patients hospitalized with 2009 H1N1 influenza. We sought to assess the immunogenicity and safety of an unadjuvanted, inactivated 2009 H1N1 vaccine in patients with severe versus mild-to-moderate asthma. We conducted an open-label study involving 390 participants (age, 12-79 years) enrolled in October-November 2009. Severe asthma was defined as need for 880 μg/d or more of inhaled fluticasone equivalent, systemic corticosteroids, or both. Within each severity group, participants were randomized to receive intramuscularly 15 or 30 μg of 2009 H1N1 vaccine twice 21 days apart. Immunogenicity end points were seroprotection (hemagglutination inhibition assay titer ≥40) and seroconversion (4-fold or greater titer increase). Safety was assessed through local and systemic reactogenicity, asthma exacerbations, and pulmonary function. In patients with mild-to-moderate asthma (n = 217), the 2009 H1N1 vaccine provided equal seroprotection 21 days after the first immunization at the 15-μg (90.6%; 95% CI, 83.5% to 95.4%) and 30-μg (95.3%; 95% CI, 89.4% to 98.5%) doses. In patients with severe asthma (n = 173), seroprotection 21 days after the first immunization was 77.9% (95% CI, 67.7% to 86.1%) and 94.1% (95% CI, 86.8% to 98.1%) at the 15- and 30-μg doses, respectively (P = .004). The second vaccination did not provide further increases in seroprotection. Participants with severe asthma who are older than 60 years showed the lowest seroprotection (44.4% at day 21) with the 15-μg dose but had adequate seroprotection with 30 μg. The 2 dose groups did not differ in seroconversion rates. There were no safety concerns. Monovalent inactivated 2009 H1N1 pandemic influenza vaccine was safe and provided overall seroprotection as a surrogate of efficacy. In patients older than 60 years with severe asthma, a 30-μg dose might be more appropriate.
    The Journal of allergy and clinical immunology 01/2011; 127(1):130-7, 137.e1-3. · 12.05 Impact Factor
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    ABSTRACT: For children living in inner cities, asthma tends to be more frequent and severe. To characterize, understand, and treat children with asthma living in the inner city more effectively, the National Institute of Allergy and Infectious Diseases established an Inner-City Asthma Program in 1991. In addition, the revised National Asthma Education and Prevention Program Expert Panel 3 report was introduced with new concepts for asthma management that are now centered on asthma control. The purpose of this review is to highlight features of the National Institute of Allergy and Infectious Diseases Inner-City Asthma Consortium Asthma Control Evaluation study that enhance our knowledge regarding the application of the asthma guidelines and to provide a summary of lessons learned from that important study. We recognized that asthma symptoms and exacerbations are theoretically linked to underlying inflammation of airways but are not direct indicators of inflammation. Based on the observations from the Asthma Control Evaluation study, we were impressed that a systematic guidelines-based approach improved asthma control significantly over the course of the 1-year treatment period.
    The Journal of allergy and clinical immunology 03/2010; 125(3):521-6; quiz 527-8. · 12.05 Impact Factor
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    ABSTRACT: Although sensitization to fungal allergens is prevalent in inner-city children with asthma, the relationship between fungal exposure and morbidity is poorly understood. We examined relationships between fungal sensitization, exposure, and asthma morbidity in inner-city children. Participants were 5 to 11 years old and enrolled in the Inner-City Asthma Study. This report includes the subset of children with at least 1 positive skin test (PST) response to a fungal allergen extract; for these children, indoor and outdoor airborne culturable fungi levels were measured at baseline and throughout the 2-year study. Asthma morbidity measures were collected prospectively. The primary outcome was symptom days per 2 weeks. At baseline, children with a PST response to a fungal allergen extract had significantly more symptom days compared with those without a PST response to any fungal allergen extract (6.3 vs 5.7 days per 2 weeks, P = .04). During the study, increases in total fungal exposure and indoor Penicillium species exposure were associated with increases in symptom days and asthma-related unscheduled visits. Indoor exposures to total fungi and to Penicillium species were associated with significant increases in unscheduled visits, even after controlling for outdoor fungal levels. Adverse effects associated with exposure to a specific fungus were stronger among children with PST responses to that fungal allergen extract compared with those seen in children with negative skin test responses. Outdoor fungal exposure is primarily associated with increased asthma symptoms and increased risk of exacerbations in this population.
    The Journal of allergy and clinical immunology 03/2010; 125(3):593-9. · 12.05 Impact Factor
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    ABSTRACT: There is an association between adiposity and asthma prevalence, but the relationship to asthma control is unclear. We sought to understand the relationships among adiposity, sex, and asthma control in inner-city adolescents with asthma. We prospectively followed 368 adolescents with moderate-to-severe asthma (ages 12-20 years) living in 10 urban areas for 1 year. Asthma symptoms and exacerbations were recorded, and pulmonary function and exhaled nitric oxide levels were measured every 6 weeks. Adiposity measures (body mass index [BMI] and dual-energy X-ray absorptiometric scans) were made, and blood was collected for measurement of allergy markers, adiponectin, leptin, TNF-alpha, IL-6, and C-reactive protein levels. More than 60% of female subjects and 50% of male subjects were above the 85th percentile of BMI for age. Higher BMI was associated with more symptom days (R = 0.18, P = .02) and exacerbations (R = 0.18, P = .06) among female subjects only. Adiponectin was inversely related to asthma symptoms (R = -0.18, P < .05) and exacerbations (R = -0.20, P < .05) and positively with FEV(1)/forced vital capacity ratio (R = 0.15, P < .05) in male subjects only independent of body size. There was no relationship between adiposity or adipokines and total IgE levels, blood eosinophil counts, and exhaled nitric oxide levels. Dual-energy X-ray absorptiometry provided little additional value in relating adiposity to asthma outcome in this population of adolescents. Adiposity is associated with poorer asthma control in female subjects. Adiponectin is associated with improved asthma control in male subjects.
    The Journal of allergy and clinical immunology 03/2010; 125(3):584-92. · 12.05 Impact Factor
  • Journal of Allergy and Clinical Immunology 02/2010; 125(2). · 11.25 Impact Factor

Publication Stats

4k Citations
721.90 Total Impact Points


  • 2002–2012
    • University of North Carolina at Chapel Hill
      North Carolina, United States
  • 2010
    • Northwestern University
      Evanston, Illinois, United States
  • 2009
    • National Institute of Allergy and Infectious Diseases
      Maryland, United States
  • 2008
    • Children's Memorial Hospital
      Chicago, Illinois, United States
  • 2007
    • University of Wisconsin, Madison
      • Department of Medicine
      Mississippi, United States
  • 2005–2007
    • Mount Sinai School of Medicine
      • Department of Pediatrics
      Manhattan, NY, United States
    • University of Texas Southwestern Medical Center
      Dallas, Texas, United States
  • 2003–2007
    • National Institutes of Health
      • Division of Intramural Research (Dental Research)
      Bethesda, MD, United States
  • 2006
    • University of Washington Seattle
      • Department of Pediatrics
      Seattle, WA, United States
  • 2004
    • The University of Arizona
      • Respiratory Center
      Tucson, AZ, United States
  • 2001–2004
    • National Institute of Environmental Health Sciences
      Durham, North Carolina, United States
  • 1999
    • Case Western Reserve University School of Medicine
      • Department of Pediatrics
      Cleveland, OH, United States
  • 1997–1999
    • New England Research Institutes
      Watertown, Massachusetts, United States