Prevalence and risk factors for asthma in Poland: results from the PMSEAD study

BACKGROUND

The prevalence of asthma depends on both hereditary and environmental factors. Knowledge of the effects of environmental and congenital factors on the frequency of occurrence of asthma may provide important clues to its pathogenesis and prevention.

OBJECTIVES

The Polish Multicentre Study of Epidemiology of Allergic Diseases was designed to obtain estimates representative of the entire Polish population to assess asthma prevalence and risk factors.

METHODS

Thirty-three areas were selected in 11 regions of Poland. Epidemiologic diagnoses of asthma were verified by a single recognized expert in each region on the basis of collected data as well as available medical documentation, in accordance with the 1997 guidelines of the Global Initiative for Asthma. Ambient air concentrations of sulfur dioxide and suspended particulates (black smoke) were measured directly or estimated by statistical modelling.

RESULTS

Results were obtained for asthma in 16 238 subjects, including 3268 children (aged 3 to 16 years) and 12 970 adults (17 to 80 years). The overall prevalence of asthma was 8.6% (95% confidence interval [CI], 7.7%-9.6%) among children and 5.4% (95% CI, 5.0%-5.8%) among adults. Several risk factors for asthma were identified: family history of asthma, black smoke, residential exposure to traffic-related air pollution in both children and adults, and damp or overcrowded housing in adults. No statistically significant association was observed for passive smoking in the home, use of gas stoves, pet ownership, or exposure to ambient air pollution with sulfur dioxide.

CONCLUSION

Our results show that the prevalence of asthma is associated with several host and environmental factors in the Polish population.

Allergen immunotherapy decreases specific allergen-induced expression of Fas and FasL on CD4+ and CD8+ cells

Apoptosis programmed cell death without induction of an inflammatory response. It is mediated by Fas--a cell surface protein which is expressed on activated lymphocytes. Interaction with its counterpart--the Fas ligand induces the apoptosis of Fas bearing cells. The mechanism underlying successful immunotherapy has not been identified. The aim of this study was to investigate whether specific immunotherapy (SIT) might affect Fas and FasL expression after stimulation with specific allergen. The study was conducted on 8 allergic subjects and 8 healthy volunteers as controls. The allergic patients were treated with conventional SIT (Pollinex). Blood samples were collected before the first day and 7 days after the last injection. Isolated CD4+ and CD8+ cells were incubated in various concentrations of specific allergen (1, 10, 100 ng/ml) or in medium alone. Indirect immunofluorescence test with rabbit IgG against human Fas and FasL was performed. The percentage of positive cells was determined under fluorescence microscope. The expression of Fas and FasL before SIT was significantly increased on CD4+ and CD8+ cells under the influence of specific allergen (10, 100 ng/ml). After SIT, significant decrease in the expression of both molecules was observed, although elimination of allergen-reactive cells was not complete and their number was still higher than in the controls.

CONCLUSION

The exposure of CD4+ and CD8+ cells on allergen may induce the Fas-FasL apoptotic pathway. Significant decrease in number of allergen-reactive CD4+, CD8+ cells after SIT suggests participation of the phenomenon in deletion of clones, which may be a part of the allergen tolerance mechanism achieved naturally or during SIT.

Skin reactivity to histamine and expression of histamine receptors mRNA in lymphocytes of healthy subjects and non-small-cell lung cancer patients before and after surgery

Histamine modulates an immunological response through stimulation of appropriate receptor--H1R proinflammatory or H2R suppressive. The participation of histamine in regulation of an immunological response in the course of neoplastic disease is determined by the expression of particular receptor. The aim of our work was the investigation of the expression of mRNA of two types of histamine receptors in peripheral blood lymphocytes and the evaluation of skin-prick test with histamine in lung cancer patients before and after surgery. The investigation was performed on 15 patients qualified to surgery before and 7-10 days after treatment and on 12 healthy subjects. Reverse transcriptase polymerase chain reaction (RT-PCR) with primers labeled with fluorescent dyes was performed. Intensity of fluorescence was expressed as relative fluorescence units (RFU). The data were analysed using ABI Prism 310 GeneScan collection software Version 3.1. Skin-prick test with histamine was evaluated after 10 min by measuring the diameter of the weal. The expression of H1R and H2R mRNA in healthy subjects was not significantly different in contrast to the lung cancer patients in which a significant prevalence of H2R mRNA expression was observed before surgery and only slightly decreased after (P < 0.001). Skin-prick test--negative in one patient before surgery, after treatment was positive in all patients and the diameter of histamine weal was significantly increased (P < 0.001). One may assume that the prevalence of the expression of H2R mRNA in patients reflects the status of immunosuppression caused by cancer. Since histamine exerts its suppressive activity trough H2R it seems reasonably to include the antagonists of this receptor to the cancer therapy which may restore a relative balance between accessibility of both types of histamine receptors.

Equivalent asthma control and systemic safety of inhaled budesonide delivered via HFA-134a or CFC propellant in a broad range of doses

The aim of the present study was to demonstrate an equivalent asthma control and safety of inhaled budesonide 200 microg unit-dose via a spacer device (Jet Spacer, Chiesi Farmaceutici S.p.A.) given with an HFA-134a or CFC propellant in stable patients treated with inhaled corticosteroids. A total number of 270 patients, 134 in the HFA-134a group and 136 in the CFC group, completed a 2-week run-in period and were then randomised to receive a daily dose of inhaled budesonide (low dose: 400 microg, medium dose: 800 microg, high dose: 1200 or 1600 microg), defined on the basis of the dose of previous inhaled steroids given twice daily for 12 weeks. Morning and evening PEFR, intake of rescue salbutamol, number of day-time and night-time asthma attacks, number of night-time awakenings due to asthma and clinical symptoms were recorded daily by patients on diary cards. Pulmonary function tests (FEV1, FVC, PEFR and MEF50) and vital signs were measured at the clinics at study entry, at the start of treatment and after 2, 4, 8 and 12 weeks thereafter. Morning serum cortisol (8.00-10.00 AM) was measured at baseline and in the final visit. Adverse events and vital signs were recorded throughout the total study period. Small increases vs. baseline for lung function (more markedly in the high-dose subsets) and significant decreases of symptoms and use of rescue salbutamol were similarly observed in both groups. Equivalence was demonstrated for the primary endpoint morning PEFR (difference between means = -1.51 l/min; 95% CI: -9.40-6.37 l/min; pre-defined limits: +/- 42.16 l/min, i.e. +/- 10% of the reference LSM) as well as for evening PEFR and FEV1, both in the ITT population or on a per-protocol basis. No statistically significant differences between groups were observed in any of the other efficacy variables. A similar proportion of drug-related adverse events was observed in the two groups, without drug-related serious events in either group. No evidence of adrenal depletion was also noted with both propellants. In conclusion, the budesonide HFA-134a formulation given with a spacer device provided an equivalent asthma control with that of a corresponding CFC product, when administered in stable patients treated with inhaled corticosteroids in a broad range of daily doses. The use of the new propellant did not modify the safety profile of inhaled budesonide.

Prevalence of asthma with aspirin hypersensitivity in the adult population of Poland

BACKGROUND

Acetylsalicylic acid (ASA) and other nonsteroid anti-inflammatory drugs (NSAIDs) are reported to account for 21-25% of all adverse drug reactions. Some asthmatics may react to ASA and other NSAIDs with acute bronchoconstriction, profuse rhinorrhea and skin flushing. This is a distinct clinical syndrome called aspirin-induced asthma (AIA). The prevalence of AIA among asthmatic patients in Poland has not been previously assessed.

METHODS

A questionnaire survey of 12,970 adults of both sexes, randomly selected from the population of Poland.

RESULTS

The prevalence of AIA in the general population of Poland was estimated as 0.6%. Thirty patients (4.3%; 95% CI: 2.8-5.8) of 703 asthmatics (5.4% of general population) reported symptoms attesting to hypersensitivity to aspirin. In 27% of them the reactions were precipitated by aspirin, whereas in the remaining subjects by other NSAIDs.

CONCLUSIONS

The prevalence of AIA in Poland is 4.3%, being somewhat lower than in Finland and Australia, where it was recently reported to account for 8.8 and 10.9% of the adult asthmatics, respectively. These figures indicate that aspirin hypersensitivity might be a significant community problem.

Formoterol in patients with chronic obstructive pulmonary disease: a randomized, controlled, 3-month trial

The aim of this study was to investigate formoterol, an inhaled long-acting beta2-agonist, in patients with chronic obstructive pulmonary disease (COPD). Six-hundred and ninety-two COPD patients, mean baseline forced expiratory volume in one second (FEV1) 54%, FEV1/forced vital capacity 75% of predicted, reversibility 6.4% pred, were treated with formoterol (4.5, 9 or 18 microg b.i.d.) or placebo via Turbuhaler for 12 weeks. Symptoms were recorded daily. Spirometry and the incremental shuttle walking test (SWT) were performed at clinic visits. Compared with placebo, 18 microg b.i.d. formoterol reduced the mean total symptom score by 13% and increased the percentage of nights without awakenings by 15%. Formoterol (9 and 18 microg b.i.d.) significantly reduced symptom scores for breathlessness (-7% and -9%, respectively) and chest tightness (-11% and -8%, respectively), reduced the need for rescue medication (-25% and -18%, respectively), and increased symptom-free days (71% and 86%, respectively). FEV1 improved significantly after all three doses of formoterol (versus placebo). No differences were found between groups in SWT walking distance. No unexpected adverse events were seen. In conclusion, 9 and 18 microg b.i.d. formoterol reduced symptoms and increased the number of symptom-free days in a dose-dependent manner in chronic obstructive pulmonary disease patients. Formoterol improved lung function at a dose of 4.5 microg b.i.d. and higher.

Safety of formoterol Turbuhaler at cumulative dose of 90 microg in patients with acute bronchial obstruction

This study compared the safety of formoterol (Oxis Turbuhaler; 90 microg delivered dose; 120 microg metered dose) with terbutaline (Bricanyl Turbuhaler; 10 mg), in patients with acute bronchoconstriction. Forty-eight patients (31 females) with a mean age of 45 yrs, were randomized into two parallel groups (double-blind design). Mean baseline forced expiratory volume in one second (FEV1) was 0.98 L (33% of predicted normal). Study drugs were administered on six occasions during 3 h (formoterol 4.5 microg or terbutaline 0.5 mg x inhalation(-1), 20 inhalations). Patients received intravenous prednisolone after 1.5 h and oxygen during the first 3 h. Pulse rate, serum potassium, 12-lead electrocardiogram (ECG), Holter ECG, arterial blood gases and FEV1 were assessed during 12 h after the first dose. Four patients (one formoterol, three terbutaline) discontinued. The 12-h mean values of serum potassium decreased from 4.02 to 3.89 mmol x L(-1) for formoterol and from 4.22 to 3.76 mmol x L(-1) for terbutaline. Mean 12-h pulse rate was significantly (p<0.01) higher in the terbutaline group (101.7 beats per minute (bpm)) than in the formoterol group (93.5 bpm). No individual patient value was considered clinically important or alarming. FEV1 improved in both groups but with no statistically significant difference between treatments. Oxis Turbuhaler (90 microg) was at least as safe and well tolerated as terbutaline (10 mg) [DOSAGE ERROR CORRECTED] in patients with acute bronchoconstriction.

Histamine regulates T-cell and antibody responses by differential expression of H1 and H2 receptors

Many pathological processes, including those causing allergies and autoimmune diseases, are associated with the presence of specialized subsets of T helper cells (TH1 and TH2) at the site of inflammation. The diversity of TH1 and TH2 function is not predetermined but depends on signals that drive the cells towards either subset. Histamine, released from effector cells (mast cells and basophils) during inflammatory reactions can influence immune response. Here we report that histamine enhances TH1-type responses by triggering the histamine receptor type 1 (H1R), whereas both TH1- and TH2-type responses are negatively regulated by H2R through the activation of different biochemical intracellular signals. In mice, deletion of H1R results in suppression of interferon (IFN)-gamma and dominant secretion of TH2 cytokines (interleukin (IL)-4 and IL-13). Mutant mice lacking H2R showed upregulation of both TH1 and TH2 cytokines. Relevant to T-cell cytokine profiles, mice lacking H1R displayed increased specific antibody response with increased immunoglobulin-epsilon (IgE) and IgG1, IgG2b and IgG3 compared with mice lacking H2R. These findings account for an important regulatory mechanism in the control of inflammatory functions through effector-cell-derived histamine.

Efficacy and safety of dofetilide in the prevention of symptomatic episodes of paroxysmal supraventricular tachycardia: a 6-month double-blind comparison with propafenone and placebo

BACKGROUND

Existing drug therapies for paroxysmal supraventricular tachycardia (PSVT) have potentially serious adverse effects. Dofetilide, a pure class III antiarrhythmic agent, may offer an effective and safe alternative for treating PSVT. This study compared the efficacy and safety of dofetilide with that of propafenone and placebo in the prevention of PSVT.

METHODS

This multicenter, randomized, placebo-controlled, parallel-group study compared the effectiveness of oral dofetilide 500 microg given twice daily with that of propafenone 150 mg given 3 times a day and placebo in preventing the recurrence of PSVT in 122 symptomatic patients. Episodes of PSVT were documented by symptom diaries and Hertcard (Hertford Medical, Hertfordshire, UK) event recorders.

RESULTS

After 6 months of treatment, patients taking dofetilide, propafenone, and placebo had a 50%, 54%, and 6% probability, respectively, of remaining free of episodes of PSVT (P <.001 for both dofetilide and propafenone vs placebo). Both dofetilide and propafenone also decreased the frequency of episodes of PSVT; the median numbers of episodes in the dofetilide- and propafenone-treated groups were 1 and 0.5, respectively, compared with 5 in the placebo-treated group. Dofetilide was well tolerated; no proarrhythmia occurred. Three patients taking propafenone had serious treatment-related adverse effects that required drug discontinuation.

CONCLUSIONS

Dofetilide and propafenone were equally effective in preventing the recurrence of or decreasing the frequency of PSVT.

Severe tracheobronchial stenosis in a patient with Crohn's disease

Tracheobronchial involvement in Crohn's disease is rare, usually associated with symptoms of tracheobronchitis, and typically responds well to steroids. The authors report a case of a 29-yr old patient with Crohn's disease, who presented with dyspnoea, fever, and a productive cough. Computed tomography of the chest revealed extensive nodular tracheobronchial stenosis, that was accompanied by severe mucosal inflammation at bronchoscopy. High-dose oral steroids diminished the mucosal inflammation, but had limited efficacy on the underlying tracheobronchial stenosis. It is speculated that this relative ineffectiveness of steroids may be due to the persistence of the untreated inflammatory process.

[Budesonide (Turbuhaler) at a dosage of 400 micrograms per day is at least as effective as a double dose of beclomethasone (MDI) in patients with mild to moderately severe bronchial asthma]

BACKGROUND

Recent investigations revealed that in patients with bronchial asthma the same anti-inflammatory effect is achieved by inhalation of half the dose of budesonide by a Turbuhaler (i.e. by using corticosteroid in powder form) as by a full dose of beclomethasone driven into the lungs by compressed chlorofluorocarbons (i.e. MDI = pressure dosage inhalator). The objective was to assess whether there is a difference between 12-week treatment with budesonide Turbuhaler in a smaller dose of 400 micrograms/day and treatment with beclomethasone dipropionate MDI 800 micrograms/day.

METHODS AND RESULTS

After an initial two-week period of the 227 patients with mild or medium severe asthma who had not taken corticosteroids for three months, into the budesonide Turbuhaler group 94 patients were included and into the beclomethasone MDI group 99 patients. Characteristics: group treated with budesonide (46 men, 48 women, mean age 38 years, FEV1 78% of appropriate values). Group treated with beclomethasone (51 men, 48 women, mean age 39 years, FEV1 81.5% of appropriate values). Morning and evening values of the peak expiration rate (PEF) increased significantly after budesonide treatment 2 x 200 micrograms/day) as compared with beclomethasone treatment (2 x 400 micrograms/day). Differences of morning PEF between budesonide and beclomethasone: 47:28 l/min, p < 0.05, differences of evening PEF: 32:10 l/min., p < 0.027. The number of dyspnoic attacks declined after both types of treatment, as well as the amount of inhaled bronchodilatating substances (terbutalin Turbuhaler). The differences between drugs were however not statistically significant.

CONCLUSIONS

Budesonide Turbuhaler, 400 micrograms/day when administered to patients with bronchial asthma was at least as effective as beclomethasone MDI, 800 micrograms/day. The increase of morning and evening PEF values was after budesonide significantly higher than after beclomethasone.

Modulation of adhesion and chemotaxis of human neutrophils by cortisol, transforming growth factor-beta and antiinflammatory drugs

Neutrophils are the first cells that accumulate in response to stimuli from the arising inflammation site. We have studied the influence of commonly used antiinflammatory (acetylsalicylic acid) and immunosuppressive (cyclosporin A, methotrexate) drugs and endogenous substances of antiinflammatory activity (cortisol, transforming growth factor-beta; TGF-beta) on the interdependent phenomena of cell motility and adhesion. Neutrophils from healthy subjects were preincubated with various concentrations of these substances and adhesion to plastic-bound monoclonal antibodies to CD11a/CD18, CD11c/ CD18 and CD44 was determined. We have found that the studied drugs significantly lowered adhesion (by 40%) of neutrophils to the ligands. Simultaneously, cell motility was investigated according to the Boyden method. We found a significant dose-dependent increase in the motility of this cells in a range comparable to conventional chemoattractants for neutrophils. These data indicate that simultaneous enhancement of motility and reduction of adhesion might be a common pathway for the mechanisms of action of the most common anti-inflammatory drugs.

Acetylator phenotype in patients with allergic diseases and its clinical significance

The genetic polymorphism of drug acetylation rate in man is an important determinant of the toxic and therapeutic response to certain drugs. This polymorphism can alter not only drug effects but may be a factor influencing the frequency of the occurrence of some disease states. The aim of our study was to establish whether there exists any correlation between the acetylator phenotype and the development of allergic diseases. In patients with allergic diseases and in healthy persons as a control group, the acetylation phenotype was determined by the sulfadimidinic method. In the group of patients with allergic diseases without infectional factor 76% slow and 24% rapid acetylators were found. This predominance of slow acetylators was statistically significant (by using chi 2 test) with comparison to the group of healthy persons, where 49% slow and 51% rapid acetylators were observed. Considerable predominance of slow acetylators in patients with allergic diseases suggest that phenotype of slow acetylation may be a factor playing some role in pathogenesis of allergic diseases and may be a factor predisposing to the development of these diseases.