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Ulrich Wahn

Publications and source records attributed to Ulrich Wahn.

70 records · Page 4Linked to original sources

How should a birth cohort study be organised? Experience from the German MAS cohort study.

Birth cohort studies offer the opportunity to study average risks, rates and occurrence times of disease longitudinally from birth. The effect of genetic and environmental factors and their interactions can be studied. Furthermore, quantity and duration of exposure to environmental agents can be evaluated prospectively. However, prospective birth cohort studies are expensive, labour intensive and take many years to complete. Loss of subjects over time as well as recall bias complicate the interpretation of observations. This paper summarises the potential pitfalls of such studies and discusses the experience of the German Multicentre Allergy Study (MAS), which began in 1990 in five German cities and included 1314 newborns for the study of the natural course of atopic diseases.

Cohort Studies↗

Placebo-controlled study of the mite allergen-reducing effect of tannic acid plus benzyl benzoate on carpets in homes of children with house dust mite sensitization and asthma.

We studied the effect of a spray containing 1% benzyl benzoate, an acaricide, and 1% tannic acid ('Lowal'; a protein-denaturing substance), on concentrations of major allergens from house dust mite (HDM) species Dermatophagoides pteronyssinus and D. farinae (Der p 1 and Der f 1, respectively) in carpets. In a double-blind, placebo-controlled study with crossover design, 30 homes of children with HDM sensitization and asthma were included. All houses showed > or = 400 ng/g of Der p 1 + Der f 1 in carpet dust. The first treatment was performed on day 0 (group 1 active treatment, n = 15; group 2 placebo treatment, n = 15). After 2 and 8 weeks, dust samples were collected for quantification of mite allergens. After a 2-week washout period, the second treatment was performed (group 1 placebo treatment; group 2 active treatment). Again, carpet dust was collected after 2 and 8 weeks. Twenty-two of 30 families completed the trial: 14/15 in group 1 and eight of 15 in group 2. On day 0, there was no significant difference in mite allergen exposure between group 1 and group 2 (1,498 vs. 2,239 ng/g of Der p 1 + Der f 1, respectively). In group 1, the geometric mean for the difference of mite allergen concentration comparing day 0 and week 6 was 196 ng/g (95% CI: -7,161 and 8,401) for the first treatment (active) and 15 ng/g (95% CI: -1,079 and 1,292) for the second treatment (control). In group 2, the difference was 66 ng/g (95% CI: -398 and 1,515) for the first treatment (control) and 609 ng/g (95% CI: 186 and 9,264) for the second treatment (active). Comparing placebo and active treatment in total, there was a significant decrease following placebo treatment after 14 days (p = 0.026). After 8 weeks, active treatment was superior to placebo treatment (p = 0.049), but the allergen reduction achieved was < 20% (median 1,500 ng/g on day 0 vs. 1,250 ng/g after 8 weeks). We conclude that the slight mite allergen reduction on carpets achieved by the treatment with 'Lowal' is unlikely to achieve worthwhile clinical benefit either in the treatment of mite-sensitive patients or in primary or secondary prophylaxis.

Antigens, Dermatophagoides↗

Evaluation of a parental training program for the management of childhood atopic dermatitis.

Atopic dermatitis (AD) in childhood is a common disease with prevalence rates as high as 20%. Its early onset in infancy and its chronic relapsing course puts a special burden on families. Supporting parents in dealing with the management of AD presents a challenge for physicians. The objective of this study was to determine the effect of a structured parental training program on managing AD in children. Two-hundred and four families participated in a prospective, randomized controlled trial. Children (5 months to 12 years in age) had suffered from moderate-to-severe AD for at least 4 months. They were randomly assigned to either the intervention group or a waiting, control group who could participate in the training program 1 year later. The intervention was an inter-disciplinary, structured educational program which covered medical, nutritional, and psychological issues in six group sessions of 2 h each. The families were assessed at the beginning of the study and 1 year later. Main outcome measures were: severity of eczema (SCORAD); treatment habits; treatment costs; quality of life; and coping strategies. Significant effects were shown regarding treatment behavior, such as regular use of emollients, use of antiseptics and topical steroids in the event of exacerbation, and a reduction in the use of unconventional therapies. Satisfaction with medical treatment was improved, and rumination as an ineffective coping strategy was reduced. Finally, significant reduction of treatment costs was achieved. We conclude that structured training programs for parents of children with AD is a helpful adjunct to dermatological treatment.

Adaptation, Psychological↗

Is early BCG vaccination associated with less atopic disease? An epidemiological study in German preschool children with different ethnic backgrounds.

We investigated the association of bacille Calmette-Guérin (BCG) vaccination and atopic manifestations among children. Because many children in the study area were from minority ethnic groups, the effect of ethnicity on disease prevalence was also analyzed. A mandatory health survey included all preschool children from Berlin in 1994. Trained medical personnel asked parents whether their child had ever had a diagnosis of atopic dermatitis (AD), bronchial asthma (BA), and hay fever (HF) or symptoms suggestive of these conditions. BCG-vaccination status was recorded from official vaccination documents. Ethnicity of the child was defined by maternal citizenship. We included 38 808 children in our study (20 813 children from former west Berlin), on average aged 6 years. The proportion of children with a foreign family background was 2.1% in East Berlin and 27.5% in West Berlin. BCG vaccination was more common in East Berlin than in West Berlin (94.2% vs. 16.5%) and in West Berlin more common among children with a foreign family background compared with Germans (25.3% vs. 13.2%). The adjusted odds ratio (95% CI) for BA was 0.85 (0.71-1.00) for BCG-vaccinated individuals. BCG vaccination was not significantly associated with AD or HF. Among non-German children, the odds ratios were 0.35 (0.30-0.42) for AD, 0.58 (0.48-0.70) for BA, and 0.72 (0.54-0.92) for HF. The OR for AD among children living in eastern Berlin was 1.19 (1.04-1.36), no significant regional differences were found for BA or HF. This study demonstrated a weak protective effect of BCG vaccination against asthma but a much stronger protective effect of non-German ethnicity against atopic manifestations among preschool children from Germany.

Asthma↗

Pollen immunotherapy reduces the development of asthma in children with seasonal rhinoconjunctivitis (the PAT-study).

BACKGROUND: Children with allergic rhinitis are likely to develop asthma. OBJECTIVE: The purpose of this investigation was to determine whether specific immunotherapy can prevent the development of asthma and reduce bronchial hyperresponsiveness in children with seasonal allergic rhinoconjunctivitis. METHODS: From 6 pediatric allergy centers, 205 children aged 6 to 14 years (mean age, 10.7 years) with grass and/or birch pollen allergy but without any other clinically important allergy were randomized either to receive specific immunotherapy for 3 years or to an open control group. All subjects had moderate to severe hay fever symptoms, but at inclusion none reported asthma with need of daily treatment. Symptomatic treatment was limited to loratadine, levocabastine, sodium cromoglycate, and nasal budesonide. Asthma was evaluated clinically and by peak flow. Methacholine bronchial provocation tests were carried out during the season(s) and during the winter. RESULTS: Before the start of immunotherapy, 20% of the children had mild asthma symptoms during the pollen season(s). Among those without asthma, the actively treated children had significantly fewer asthma symptoms after 3 years as evaluated by clinical diagnosis (odds ratio, 2.52; P <.05). Methacholine bronchial provocation test results improved significant in the active group (P <.05). CONCLUSION: Immunotherapy can reduce the development of asthma in children with seasonal rhinoconjunctivitis.

Adolescent↗

Efficacy of combination treatment with anti-IgE plus specific immunotherapy in polysensitized children and adolescents with seasonal allergic rhinitis.

BACKGROUND: Specific immunotherapy (SIT) and treatment with monoclonal anti-IgE antibody have complementary modes of action. OBJECTIVE: The purpose of this study was to determine whether combined therapy could provide better efficacy than either treatment alone. METHODS: We conducted a randomized, double-blinded trial to assess the efficacy and safety of subcutaneously administered anti-IgE (omalizumab) or placebo in children and adolescents with seasonal allergic rhinitis in both a birch pollen season and a grass pollen season (sequential seasons together lasting an average of 84 days). There were 4 treatment arms. Each subject was started on SIT-birch or SIT-grass, and anti-IgE or placebo was started before and maintained during the anticipated pollen seasons (a total of 24 weeks). The primary efficacy variable was symptom load, the sum of daily symptom severity score plus rescue medication use. RESULTS: A total of 221 subjects (intent-to-treat population) aged 6 to 17 years were analyzed for efficacy. Combination therapy reduced symptom load over the 2 pollen seasons by 48% (P <.001) over SIT alone. When analyzed separately by season, the 2 groups receiving unrelated SIT were considered placebo controls. In the grass season, symptom loads were as follows: unrelated (birch) SIT + placebo, 0.89 (reference value); unrelated (birch) SIT + anti-IgE, 0.49 (-45%); SIT-grass + placebo, 0.61 (-32%); SIT-grass + anti-IgE, 0.26 (-71%). CONCLUSION: Anti-IgE therapy conferred a protective effect independent of the type of allergen. Additional clinical benefit was demonstrated in both pollen seasons, whether there was coverage by SIT or not. This combination might prove useful for the treatment of allergic rhinitis, particularly for polysensitized patients.

Adolescent↗

Switching from conventional to extrafine aerosol beclomethasone dipropionate therapy in children: a 6-month, open- label, randomized trial.

BACKGROUND: In adults with asthma, hydrofluoralkane-134a beclomethasone dipropionate (HFA-BDP) extrafine aerosol provides equivalent asthma control at half the daily dose of conventional chlorofluorocarbon (CFC)-BDP. OBJECTIVE: We sought to compare the efficacy and tolerability of switching from CFC-BDP to HFA-BDP at half the daily dose in children with stable asthma. METHODS: This 6-month, open-label, randomized, multicenter study enrolled 520 children aged 5 to 11 years with well-controlled asthma receiving inhaled CFC-BDP or budesonide 200 to 800 microg/d x. (Four hundred fifty-two patients were using doses within the recommended range of 200-400 microg and were analyzed separately.) During a 4-week run-in period, patients used CFC-BDP plus a spacer (CFC-BDP+S) at approximately the same dose as they were using before study entry. Patients were then randomized in a 1:3 ratio to continue on CFC-BDP+S or switch to HFA-BDP Autohaler at half the daily dose. RESULTS: The change from baseline in morning peak expiratory flow was significantly greater in patients receiving 100-200 microg of HFA-BDP compared with those receiving 200-400 microg of CFC-BDP+S at weeks 7 to 8 (8.5 and 0.4 L/min, respectively; P =.014), with continuing improvement in both groups over 6 months (12.2 and 12.4 L/min, respectively, at month 6). There were no significant differences between treatments in mean change from baseline in FEV(1), percentage of days or nights without asthma symptoms, and daily beta-agonist use over the 6-month treatment period. The proportion of patients who had one or more asthma exacerbations, the incidence of adverse events, and the percentage change from baseline in 24-hour urinary free cortisol levels were similar in the 2 treatment groups. CONCLUSIONS: This study confirms that asthma control can be well maintained in children when switching from CFC-BDP+S to an HFA-BDP Autohaler at doses as low as 100 to 200 microg/d.

Administration, Inhalation↗

Endotoxins prevent murine IgE production, T(H)2 immune responses, and development of airway eosinophilia but not airway hyperreactivity.

BACKGROUND: Contact with immunomodulatory factors, such as LPS, in early infancy is associated with decreased allergen sensitization. OBJECTIVE: We sought to study the effects of systemic or airway exposure with LPS on the development of allergen sensitization, eosinophilic airway inflammation, and increased in vivo airway reactivity (AR) in a mouse model. METHODS: BALB/c mice were systemically sensitized with ovalbumin (OVA) plus adjuvant on days 1 and 14 and challenged through the airways with allergen on days 34 to 36. We performed measurement of OVA-specific IgE serum levels, in vitro T(H)2 cytokine production, differential cell counts in bronchoalveolar lavage fluids, and assessment of in vivo AR to inhaled methacholine by means of barometric whole-body plethysmography. RESULTS: Systemic LPS administration before OVA sensitization reduced OVA-specific IgE serum levels (426 +/- 76 vs 880 +/- 104 U/mL, P <.01), T(H)2 cytokine production by splenic mononuclear cells (IL-4: 0.08 +/- 0.01 vs 0.17 +/- 0.01 ng/mL; IL-5: 1.98 +/- 0.52 vs 4.11 +/- 0.54 ng/mL; P <.01), and extent of airway eosinophilia (total cell counts: 93 vs 376 x 10(3)/mL; eosinophils: 23% vs 51%; P <.01) compared with that in OVA-sensitized mice. Local LPS administration to sensitized mice before airway allergen challenges particularly induced IFN-gamma production by peribronchial lymph node cells in vitro (1718 +/- 315 vs 483 +/- 103 ng/mL, P <.01) associated with reduced airway eosinophilia compared with that seen in OVA-sensitized mice. Development of increased AR was not affected by systemic or local LPS exposure. Inhibitory effects of LPS on allergen sensitization and eosinophilic airway inflammation were inhibited by administration of anti-IL-12 antibodies before LPS exposure. CONCLUSION: These data indicate that local and systemic application of LPS modulates systemic and local T(H)1/T(H)2 immune responses in a distinct but similarly IL-12-dependent mode.

Allergens↗

Effect of growth hormone on exercise tolerance in children with cystic fibrosis.

PURPOSE: The effect of growth hormone (GH) treatment on exercise tolerance in children with cystic fibrosis was investigated. METHODS: 10 prepubertal children (mean +/- SD; age: 12.1 +/- 1.7 yr; height: 137.4 +/- 9.2 cm; body mass: 27.8 +/- 4.2 kg; forced expiratory volume in 1 s (FEV1): 68 +/- 22% predicted) were randomly assigned to either control period (CON, standard therapy) or recombinant human growth hormone (GH) period (additional GH treatment, 0.11-0.14 IU.kg-1, daily, s.c.) for the first 6 months, and then assigned to the other period for the next 6 months. At study entry and after each period, anthropometric data, pulmonary function, and exercise capacity (peak exercise capacity, .VO(2peak), and isokinetic muscle strength) were measured. RESULTS: Changes in height (+4.3 +/- 1.0 cm), total body mass (+2.2 +/- 0.8 kg), and lean body mass (LBM, +2.9 +/- 0.7 kg) were significantly higher (P < 0.01) after GH treatment compared with CON. Pulmonary function did not significantly change in either of the periods. In contrast to CON, GH treatment improved absolute .VO(2peak) (+19%, P < 0.01), peak ventilation (+14%, P < 0.01), and peak oxygen pulse (+18%, P < 0.01). Analysis of variance revealed that most of the changes (71%) in .VO(2peak) could be explained by those in LBM and FEV1 (P = 0.001). CONCLUSION: GH treatment clearly improved exercise tolerance, presumably resulting from the combined effects of GH on the muscular, cardiovascular, and pulmonary capacity.

Adolescent↗

Immunotherapy in children.

PURPOSE OF REVIEW: Specific allergen immunotherapy although being performed for almost 100 years, is still being addressed in clinical trials. In children the sublingual allergen application has gained considerable interest. RECENT FINDINGS: Controlled long-term trials suggest that specific allergen immunotherapy has the capacity to modify the natural history of allergic airway disease by reducing the incidence of new sensitivities non-specifically, reducing allergic symptoms years after discontinuation and preventing the incidence of asthma. The current evidence on sublingual immunotherapy is not sufficient to recommend this mode of treatment in clinical practice yet. SUMMARY: Specific allergen immunotherapy should be considered in children in whom IgE-mediated allergic symptoms cannot be adequately controlled by symptomatic treatment.

Administration, Sublingual↗

Growth, systemic safety, and efficacy during 1 year of asthma treatment with different beclomethasone dipropionate formulations: an open-label, randomized comparison of extrafine and conventional aerosols in children.

OBJECTIVE: To assess the long-term safety of hydrofluoroalkane 134a (HFA)-beclomethasone dipropionate (BDP) extrafine aerosol administered by the Autohaler compared with chlorofluorocarbon (CFC)-BDP administered by a press-and-breathe metered-dose inhaler (pMDI) and spacer (+S) in the treatment of children with asthma. METHODS: This 12-month, open-label, randomized, multicenter study enrolled 300 children who were aged 5 to 11 years and had well-controlled asthma on inhaled CFC-BDP or budesonide; 256 patients were using doses within the recommended range (200-400 microg) and were analyzed separately. Patients were randomized in a 1:3 ratio to continue on CFC-BDP+S at approximately the same dose as they were using before study entry or switch to HFA-BDP at half the daily dose. RESULTS: Asthma control was well maintained in the HFA-BDP group as evidenced by lung function tests and asthma symptoms compared with CFC-BDP+S at approximately twice the dose. There were no significant differences between the HFA-BDP 100 to 200 microg and CFC-BDP+S 200 to 400 microg treatment groups in mean change from baseline in height (5.23 cm vs 5.66 cm at month 12, respectively) or mean growth velocity from day 1 to month 12 (5.27 cm/y vs 5.71 cm/y, respectively). There were no significant differences between groups in adrenal function tests or markers of bone metabolism. CONCLUSIONS: In this long-term study in children with asthma, extrafine HFA-BDP provided long-term maintenance of asthma control at approximately half the dose compared with CFC-BDP+S. There were no clinically meaningful differences between HFA-BDP extrafine aerosol and conventional CFC-BDP+S with regard to growth or other systemic effects.

Administration, Inhalation↗

Efficacy and safety of pimecrolimus cream in the long-term management of atopic dermatitis in children.

OBJECTIVE: Pimecrolimus cream (SDZ ASM 981), a nonsteroid inhibitor of inflammatory cytokines, is effective in atopic dermatitis (AD). We assessed whether early treatment of AD signs/symptoms with pimecrolimus could influence long-term outcome by preventing disease flares. METHODS: Early intervention with pimecrolimus was compared with a conventional AD treatment strategy (ie, emollients and topical corticosteroids). In this 1-year, controlled, double-blind study, 713 AD patients (2-17 years) were randomized 2:1 to a pimecrolimus-based or conventional regimen. Both groups used emollients for dry skin. Early AD signs/symptoms were treated with pimecrolimus cream or, in the conventional treatment group, vehicle to prevent progression to flares. If flares occurred, moderately potent topical corticosteroids were mandated. The primary efficacy endpoint was ranked flares at 6 months. Safety was monitored clinically, and a skin recall-antigen test was performed at study completion. RESULTS: BASELINE CHARACTERISTICS OF THE PATIENTS: The mean age for both groups was approximately 8 years, and the majority of patients had moderate disease at baseline. PATIENT FOLLOW-UP AND EXPOSURE TO STUDY MEDICATION: The mean duration of follow-up (+/-standard error) was 303.7 (+/-5.30) days in the pimecrolimus group and 235.2 (+/-9.40) days in the control group. The discontinuation rate was significantly higher in the control group than in the pimecrolimus group (51.5% vs 31.6% at 12 months), and proportionately more patients with severe or very severe disease discontinued in the control group. The main reason for the higher discontinuation rate in the control group was unsatisfactory therapeutic effect (30.4% vs 12.4%). This resulted in a substantially higher mean number of study medication treatment days in the pimecrolimus group compared with the control group: 211.9 (69.8% of study days) versus 156.0 (66.3% of study days). Of those patients who completed 12 months on study, 14.2% and 7.0% of patients in the pimecrolimus and vehicle groups, respectively, used study medication continuously. EFFICACY: Patients in the pimecrolimus group experienced significantly fewer AD flares than those in the control group, according to the primary efficacy analysis on ranked flares of AD (Van Elteren test). The proportion of patients who completed 6 or 12 months with no flares was approximately twice as high in the pimecrolimus group compared with control (61.0% vs 34.2% at 6 months; 50.8% vs 28.3% at 12 months). Fewer flares were observed in the pimecrolimus group regardless of baseline disease severity, so even severe patients derived benefit from the treatment. The analysis of time to first flare showed that treatment with pimecrolimus was associated with a significantly longer flare-free period (log- rank test). Covariate analysis indicated a statistically significant effect on time to first flare of baseline Eczema Area and Severity Index score, and whether patients had "severe" or "very severe" disease at baseline according to the Investigators' Global Assessment, although patients in all baseline disease severity subgroups benefited from treatment. Age had no significant effect. Fewer patients in the pimecrolimus group required topical corticosteroid therapy compared with control (35.0% vs 62.9% at 6 months; 42.6% vs 68.4% at 12 months), and patients in the pimecrolimus group spent fewer days on topical corticosteroid therapy (57.4% vs 31.6% [pimecrolimus vs control, respectively] spent 0 days on topical corticosteroid therapy, 17.1% vs 27.5% 1-14 days, and 25.5% vs 41.0% >14 days over the 12 months of the study). This steroid-sparing effect of pimecrolimus was evident despite pimecrolimus-treated patients being on study longer than patients in the control group. The average proportion of study days spent on second-line corticosteroids was 4.08% in the pimecrolimus group and 9.10% in the control group. Analysis of Eczema Area and Severity Index over time showed significantly lower median scores, thus indicating better disease control in the pimecrolimus group compared with the control group. Similar results were obtained from analysis of the Investigators' Global Assessment (not shown). The treatment groups were well balanced with respect to the number of patients using antihistamines during the study (57.2% vs 62.9%, pimecrolimus vs control, respectively). SAFETY: There were no appreciable differences between treatment groups in the overall incidence of adverse events. The most frequent adverse events were common childhood infections and ailments, including nasopharyngitis, headache, and cough. The incidence of suspected drug-related adverse events was not significantly different in the pimecrolimus group (24.7% vs 18.7%--pimecrolimus vs control), and the incidence of serious adverse events was low (8.3% vs 5.2%--pimecrolimus vs control). Life-table analysis of incidence of adverse events revealed no significant differences between the treatment groups, except for cough. Local tolerability was good in both treatment groups. The most common application site reaction reported was sensation of burning (10.5% vs 9.3%--pimecrolimus vs control). There were no major differences between treatment groups in the duration or severity of application site reactions, most of which were mild-to-moderate and transient, occurring within the first week of treatment. Skin infections were reported in both groups. There were no between-group differences in the life-table analysis of time to first occurrence of bacterial skin infections nor in the adjusted incidence of bacterial skin infections. Although there were no significant differences between treatment groups in the incidence of individual viral skin infections, the incidence of grouped viral skin infections (12.4% vs 6.3%--pimecrolimus vs control) showed a slightly higher incidence in the pimecrolimus group. Laboratory values and vital signs showed no significant between-group differences. There were no significant differences between treatment groups in response to recall antigens in those patients who remained on study for 12 months. CONCLUSIONS: Treatment of early AD signs/symptoms with pimecrolimus was effective in preventing progression to flares in more than half the patients, reducing or eliminating the need for topical corticosteroids. The benefits were consistently seen at 6 months across important disease severity subgroups and with respect to the various predefined efficacy endpoints. Furthermore, these benefits were sustained for 12 months, providing evidence that long-term treatment with pimecrolimus leads to better control of AD. Treatment with pimecrolimus was well tolerated and was not associated with clinically relevant adverse events compared with the conventional treatment group. The results reported here offer the prospect of effective long-term management of AD with reduced need for topical corticosteroids.

Adolescent↗

Interactions between genes and environmental factors in asthma and atopy: new developments.

Asthma and associated phenotypes are complex traits most probably caused by an interaction of multiple disease susceptibility genes and environmental factors. Major achievements have occurred in identifying chromosomal regions and polymorphisms in candidate genes linked to or associated with asthma, atopic dermatitis, IgE levels and response to asthma therapy. The aims of this review are to explain the methodology of genetic studies of multifactorial diseases, to summarize chromosomal regions and polymorphisms in candidate genes linked to or associated with asthma and associated traits, to list genetic alterations that may alter response to asthma therapy, and to outline genetic factors that may render individuals more susceptible to asthma and atopy due to environmental changes.

Animals↗

Messages from the German Multicentre Allergy Study.

Several birth cohort studies have been initiated during the past two decades to study environmental and genetic risk factors for atopic dermatitis, asthma and allergic rhinitis. This article summarizes results from the German Multicentre Allergy Study (MAS), which has followed children (initially 1,314) from birth (in 1990) to the present time. The effects of immunizations, allergen exposure, early sensitization patterns as well as upper airway infections on the subsequent development of asthma and atopy at school age are described. Furthermore, candidate gene studies of atopic dermatitis and increased total serum IgE levels on chromosomes 5q, 12q and 17q in MAS-children and their parents are outlined.

Child↗