Cost-effectiveness of clean air administered to the breathing zone in allergic asthma.

INTRODUCTION: Airsonett Airshower (AA) is a novel non-pharmaceutical treatment for patients with perennial allergic asthma that uses a laminar airflow directed to the breathing zone of patients during sleep. It has been shown that AA treatment in addition to optimized standard therapy significantly increases asthma-related quality of life among adolescent asthmatics. However, the cost-effectiveness of AA treatment has not yet been assessed. As reimbursement decisions are increasingly guided by results from the cost-effectiveness analysis, such information is valuable for health-care policy-makers. OBJECTIVE: The objective of this study was to estimate the cost-effectiveness of adding AA treatment with allergen-free air during night sleep to optimized standard therapy for adolescents with perennial allergic asthma compared with placebo. MATERIALS AND METHODS: A probabilistic Markov model was developed to estimate costs and health outcomes over a 5-year period. Costs and effects are presented from a Swedish health-care perspective (QALYs). The main outcome of interest was cost per QALY gained. RESULTS: The Airshower strategy resulted in a mean gain of 0.25 QALYs per patient, thus yielding a cost per QALY gained of under euro35 000 as long as the cost of Airshower is below euro8200. CONCLUSIONS: Adding AA treatment to optimized standard therapy for adolescents with perennial allergic asthma compared with placebo is generating additional QALYs at a reasonable cost. However, further studies taking more detailed resource use and events such as exacerbations into account would be needed to fully evaluate the cost-effectiveness of AA treatment.

Validation of an algorithm for chronic periodontitis risk assessment and prognostication: analysis of an inflammatory reactivity test and selected risk predictors.

BACKGROUND: Patients with severe forms of chronic periodontitis present with varying degrees of decreased inflammatory reactivity. A previously reported algorithm for chronic periodontitis risk assessment and prognostication is based on the analysis of some 20 risk predictors. One of these predictors is a skin provocation test that assesses the individual patient's reactivity to a lipid A challenge. The aim of this report was to analyze results from validation data for the algorithm with respect to the contribution of results of the skin provocation test as a risk predictor for the progression of chronic periodontitis and to compare these results with the contribution from other predictors, namely smoking, angular bony destruction, furcation involvement, abutment teeth, and endodontic pathology. METHODS: Data from a previously reported clinical validation sample were used for the analysis, including the calculation of quality measures and explanatory values using different types of regression analysis and non-parametric testing. RESULTS: Smoking, endodontic pathology, abutment teeth, angular bony destruction, and furcation involvement presented with individual explanatory values for periodontitis progression between 4% and 13% and highly significant parameter estimates. Explanatory values for the results of the skin provocation test ranged between 2.6% and 5.1% depending on the disease severity group, with a positive predictive value of 82% for the identification of high-risk patients. CONCLUSION: The skin provocation test provided a clinically significant contribution to the quality of analysis with the periodontitis risk and prognostication algorithm, in particular in the selection of high-risk patients for in-depth individual tooth analysis.

Validation of an algorithm for chronic periodontitis risk assessment and prognostication: risk predictors, explanatory values, measures of quality, and clinical use.

BACKGROUND: The American Academy of Periodontology has recently stated that, "[risk assessment will become] increasingly important in periodontal treatment planning and should be part of every comprehensive dental and periodontal evaluation." (J Periodontol 2006;77:1608). Unaided risk assessment and prognostication show significant variability because chronic periodontitis is a multifactorial disease. This report summarizes the clinical validation of an algorithm for chronic periodontitis risk assessment and prognostication. The algorithm is a Web-based analytic tool that integrates some 20 risk predictors and calculates scores indicating levels of risk for chronic periodontitis for the dentition (Level I) and, if an elevated risk is found, prognosticates disease progression tooth by tooth (Level II). METHODS: An independent clinical validation sample was generated in an open, prospective clinical trial and analyzed in a predetermined validation plan. RESULTS: The analyses identified two threshold scores above which significant progression of periodontitis was found. Based on these scores, sufficiently high explanatory values with significant and increasing parameter estimates for increasing risk were established in Level I, justifying detailed analysis tooth by tooth in Level II. Subsequent prognostication of chronic periodontitis in Level II was found to be accompanied by clinically relevant measures of quality in relation to rates of disease progression. Three score intervals representing increasing levels of periodontitis progression were identified corresponding to increasing levels of significant annual marginal bone loss. CONCLUSIONS: The predictors included in the algorithm reflect a relevant selection for periodontitis risk assessment. Risk assessment and prognostication with the algorithm provides the clinician with a validated, reliable, consistent, and objective tool supporting treatment planning.

Why are some children with early onset of asthma getting better over the years?--diagnostic failure or salutogenetic factors.

Among children earlier having been identified with a hospital or primary care diagnosis of asthma at least once between 0-7 years of age, almost 40 % of their parents reported in the ISAAC-questionnaire as never having had asthma (NA). These are further analysed and compared with the persisting asthma cases (A) in this study. All these children's medical records were scrutinized concerning their asthma diagnose retrospectively.The aim of this study was to analyse possible factors related to the outcome in an Asthma diagnosis reassessment by parental questionnaire at the age of ten of the children earlier having been identified with a hospital or primary health care diagnosis of asthma at least once between 0-7 years of age in a total birth-year cohort in a defined Swedish geographical area.A multiple logistic analysis revealed four significant and independent factors associated to the improvement/non-report of asthma at the age of ten. These factors were; not having any past experiences of allergic symptoms (p<0.0001), only having one or two visits at the hospital for asthma diagnosis in the 0-7 interval (p=0.001), not living in a flat but a villa at the age of ten (p=0.029) and no previous perception of mist or mould damage in the house (p=0.052).In the early postnatal stage, obstructive and bronchospastic symptoms typical of asthma may be unspecific, and those cases not continuing to persisting disease tend to have identifiable salutogenetic factors of constitutional rather than environmental nature, namely, an overall reduced allergic predisposition.

Apoptotic eosinophils in sputum from asthmatic patients correlate negatively with levels of IL-5 and eotaxin.

BACKGROUND: Eosinophilic inflammation of the airways is a key characteristic of asthma. A defect in eosinophil apoptosis might contribute to the chronic tissue eosinophilia associated with asthma. OBJECTIVE: Our purpose was to examine whether the occurrence of apoptotic eosinophils in induced sputum from asthmatic patients correlate with interleukin (IL)-5 and eotaxin. METHODS: Thirty stable and 30 exacerbated asthmatic patients were recruited. Twenty healthy subjects were enrolled as a control group. Induced sputum was obtained from asthmatic patients and from control subjects. The number of apoptotic eosinophils in sputum was assessed by flow cytometry. In sputum supernatant, eosinophil cationic protein (ECP) was measured by sensitive radioimmunoassay, and IL-5 and eotaxin by sandwich enzyme linked immunosorbant assay. RESULTS: Levels of eosinophils, apoptotic eosinophils, IL-5, ECP and eotaxin from asthmatic patients were higher than those from healthy subjects. Thirty exacerbated asthmatics showed higher proportions of eosinophils (median 29.3%, range 13.4%-40.9%), more detectable levels of IL-5 (50.44, 32.99-67.01 pg/ml) and eotaxin (644.6, 197.4-937.7 pg/ml) in their sputum than the patients with stable asthma (P<0.05). There were significant inverse correlations between the levels of sputum IL-5 and the proportion of sputum eosinophil apoptosis in patients with exacerbated and stable asthma (r=-0.85 and -0.79, P<0.01 and P<0.05, respectively). Also inverse correlations were found between the levels of eotaxin and the proportion of sputum eosinophil apoptosis in exacerbated (r=-0.85, P<0.01), or stable asthma (r=-0.69, P<0.05). Additional positive correlations between the levels of sputum IL-5 and eotaxin in either exacerbatated (r=0.93, P<0.01) or stable asthma (r=0.82, P<0.05) were observed. CONCLUSIONS: Apoptosis of eosinophils might be suppressed by proinflammatory cytokines and chemokines such as IL-5 and eotaxin leading to their accumulation in the lung. Stimulation of eosinophils in airway with IL-5 and eotaxin may play a crucial role in allergic inflammation.

The impact of repeated spirometry and smoking cessation advice on smokers with mild COPD.

BACKGROUND: Smoking cessation is the most important therapeutic intervention in patients with chronic obstructive pulmonary diseases (COPD) and the health benefits are immediate and substantial. Major efforts have been made to develop methods with high smoking cessation rates. OBJECTIVES: To study whether a combination of spirometry and brief smoking cessation advice to smokers with COPD, annually for three years, increased their smoking cessation rate in comparison with groups of smokers with normal lung function. METHOD: Prospective, randomized study in primary care. Smoking cessation rates were compared between smokers with COPD followed-up yearly over a period of three years and smokers with normal lung function followed-up yearly for three years or followed-up only once after three years. RESULTS: The point-prevalence abstinence rate and prolonged abstinence rate at 6 and 12 months increased yearly and in smokers with COPD at year 3 was 29%, 28%, and 25%, respectively. The abstinence rates were significantly higher in smokers with COPD than in smokers with normal lung function. Smoking cessation rates among smokers with normal lung function did not increase with increasing number of follow-ups. CONCLUSION: Smokers diagnosed with COPD stopped smoking significantly more often than those with normal lung function.

Bronchial hyper-responsiveness predicts the development of mild clinical asthma within 2 yr in school children with hay-fever.

In children with mild asthma, symptoms are not always apparent. Therefore, results of tests play an important role for the diagnosis. First, to investigate whether children with bronchial hyper-responsiveness (BHR) but no symptoms of asthma in 1992 had developed clinical asthma at follow up in 1994. The second aim was to find out the diagnostic properties of tests for asthma/allergic inflammation, using either doctor diagnosed asthma (DDA), self-assessed symptoms of asthma or iso-capnic hyperventilation of cold air (IHCA), as the standard, to diagnose asthma in a group of children with hay fever. Twenty-eight children with pollinosis, 12 of them with a history of asthma for the first time during the season 1992, were studied during the birch pollen season and in the autumn of 1994. During both periods, the bronchial hyper-reactivity was estimated by methacholine bronchial provocation tests (MBPT), bronchial variability by peak expiratory flow rate variability, subjective symptoms of asthma by visual analogue scale (VAS) and bronchial inflammation by serum and urine levels of inflammatory mediators. In 1994 IHCA was added during both seasons. Eight of 16 children with BHR but without clinical asthma in 1992 had developed asthma in 1994, 14 of 16 reacted to IHCA and 13 to MBPT. All 12 children with DDA in 1992 had still asthma in 1994 and 14 children with BHR in 1992 had persistent BHR in 1994. Of 23 children with BHR in 1992, 17 had DDA in 1994 and all maintained their BHR. Furthermore, 20 of them reacted to IHCA in 1994. In 1994, 24 of 28 hay-fever children had a positive IHCA tests and 24 had positive MBPT. In relation to VAS, the sensitivity of IHCA and MBPT to predict present asthma was high, but the specificity low, whereas the specificity of most other tests was high, but based on few individuals. In relation to DDA both the IHCA test (65-80%) and the MBPT test (79-85%) had a high sensitivity and it was three to six times more likely to find a positive test among asthmatics than in non-asthmatics. Children with hay fever without clinical asthma have a high risk of developing asthma within 2 yr. In relation to DDA, inhalation of cold air and the MBPT showed a high sensitivity.

Clinically diagnosed childhood asthma and follow-up of symptoms in a Swedish case control study.

BACKGROUND: Childhood asthma has risen dramatically not only in the western societies and now forms a major and still increasing public health problem. The aims of this study were to follow up at the age of ten the patterns of asthma symptoms and associations among children with a clinically diagnosed asthma in a sizeable urban-rural community and to in compare them with demographic controls using a standardised questionnaire. METHODS: In a defined region in Sweden with a population of about 150,000 inhabitants, all children (n = 2,104) born in 1990 were recorded. At the age of seven all primary care and hospital records of the 1,752 children still living in the community were examined, and a group of children (n = 191) was defined with a well-documented and medically confirmed asthma diagnosis. At the age of ten, 86 % of these cases (n = 158) and controls (n = 171) completed an ISAAC questionnaire concerning asthma history, symptoms and related conditions. RESULTS: Different types of asthma symptoms were highly and significantly over-represented in the cases. Reported asthma heredity was significantly higher among the cases. No significant difference in reported allergic rhinitis or eczema as a child was found between cases and controls. No significant difference concerning social factors or environmental exposure was found between case and controls. Among the control group 4.7 % of the parents reported that their child actually had asthma. These are likely to be new asthma cases between the age of seven and ten and give an estimated asthma prevalence rate at the age of ten of 15.1 % in the studied cohort. CONCLUSION: A combination of medical verified asthma diagnosis through medical records and the use of self-reported symptom through the ISAAC questionnaire seem to be valid and reliable measures to follow-up childhood asthma in the local community. The asthma prevalence at the age of ten in the studied birth cohort is considerably higher than previous reports for Sweden. Both the high prevalence figure and allowing the three-year lag phase for further settling of events in the community point at the complementary roles of both hospital and primary care in the comprehensive coverage and control of childhood asthma in the community.

Prevalence and incidence of asthma related to waist circumference and BMI in a Swedish community sample.

Both asthma and obesity have become more common in affluent societies during the recent decades and several studies have shown a correlation between the presence of asthma and obesity. In order to further study this association we have investigated a population from a community in southern Sweden, where almost all inhabitants had their body indices measured as part of a study on diabetes at a primary care centre. An asthma unit working with a structured care programme for asthma was available. This organisation enabled us to study whether body mass index and waist circumference was associated with having or developing asthma. There was a significant association between both overweight, increased waist circumference and asthma, P < 0.01. The risk for developing asthma was associated with increased body weight and abdominal circumference, P < 0.05. The increase in asthma morbidity in the overweight subjects was found almost exclusively in the non-atopic asthma patients. This study confirms earlier findings of an increased prevalence of asthma in obese and overweight patients. Increased obesity and especially abdominal obesity is thus a risk factor for asthma, which probably contributes to the high prevalence of asthma in affluent societies.

Voice problems as side effects of inhaled corticosteroids in asthma patients--a prevalence study.

Voice disturbances in asthma patients may be caused by inhaled corticosteroids. In order to study the prevalence of such voice disturbances, a questionnaire was delivered to asthma patients at three asthma and allergy departments in Stockholm. The questionnaire consisted of 25 questions concerning the asthma disease symptoms, medication, voice function, and voice disturbances. A total of 350 questionnaires were delivered. Response frequency was 80%. There was a significant positive correlation between inhalation of cortison and voice disturbances. Most of the patients complained about hoarseness, followed by throat clearing, a lump in the throat, loss of voice, and less frequently, throat pain. There were no significantly differences between men and women. Elderly had more voice problems than young persons. Patients with voice-demanding professions had more problems than patients who used their voice to a lesser extent during the working day. There was a significant positive correlation between high cortison doses and voice problems as well as between voice problems and acid regurgitation.

Early detection of COPD in primary care: screening by invitation of smokers aged 40 to 55 years.

BACKGROUND: The incidence of chronic obstructive pulmonary disease (COPD) is increasing in developed countries, as is the mortality rate. The main cause of COPD is smoking, and COPD is usually diagnosed at a late stage. AIM: To evaluate a method to detect COPD at an early stage in smokers in a young age group (40-55 years). DESIGN OF STUDY: Prospective descriptive study. SETTING: The city of Motala (45,000 inhabitants) and its surrounding rural areas (43,000 inhabitants) in south-east Sweden. Nineteen thousand, seven hundred and fifty subjects were between 40 and 55 years of age. According to Swedish statistics, approximately 27% of this population are smokers. METHOD: Smokers aged between 40 and 55 years were invited to have free spirometry testing in primary healthcare centres. Placards were placed in pharmacies and health centres and advertising was carried out locally twice a year. RESULTS: A total of 512 smokers responded. The prevalence of COPD was 27% (n = 141). The COPD was classified as mild obstruction in 85% (n = 120), moderate in 13% (n = 18) and severe in 2% (n = 3) according to the European Respiratory Society classification. Knowledge of the disease COPD was acknowledged by 39% of the responders to the questionnaire. Logistic regression analysis showed that age, male sex, number of pack years, dyspnoea and symptoms of chronic bronchitis significantly increased the odds of having COPD. The adjusted odds ratio was significant for having > 30 pack years. CONCLUSIONS: This method of inviting relatively young smokers selected a population of smokers with a high incidence of COPD, and may be one way of identifying smokers with COPD in the early stages.