Peak Expiratory Flow Variability Research Articles

Effects of Ramadan Fasting on Spirometric Values and Clinical Symptoms in Asthmatic Patients

Introduction: Ramadan is the 9th Islamic lunar month during which Muslims avoid eating and drinking from sunrise to sunset. The effect of Ramadan intermittent fasting on asthma control is controversial. The aim of this study was to investigate the effects of Ramadan fasting on the spirometric variables and clinical symptoms on well-controlled asthmatic patients during Ramadan. Methods: a cohort study was conducted in Mashhad, Khorasan Razavi, Iran. Twenty-nine (19 females and 10 males) well-controlled asthmatic patients aged 47 (12) years completed the study. The average duration of fasting was 26.5 days. Assessment of spirometric variables (daily peak expiratory flow, peak expiratory flow variability, peak expiratory flow home monitoring ) as well as asthma clinical symptoms including dyspnea, cough, wheezing, and chest tightness were carried out. Results: No significant changes in clinical symptoms were reported in asthmatic patients at the end of Ramadan fasting. Among spirometric variables, only peak expiratory flow improved after Ramadan (p <0.05). There was a reduction in the mean peak expiratory flow variability from 13% at the first week of fasting to 10% at the fourth week (p <0.05). Conclusion: In well-controlled asthmatic patients, Ramadan fasting resulted in improvement in peak expiratory flow and peak expiratory flow variability.

Polymorphism of Beta2-Adrenoceptor and Regular Use of Formoterol in Asthma: Preliminary Results

Polymorphism at codon 16 of the beta2-adrenoceptor (beta2-AR) affects the responsiveness to salmeterol in asthmatics. Data concerning formoterol are more controversial in the literature. The aim of this study was to verify whether homozygous for arginine-16 (ArgArg16) and homozygous for glycine-16 (GlyGly16) genotypes differently influence the long-term responsiveness to formoterol. Twenty-nine patients with mild-to-moderate asthma, in stable clinical conditions, underwent genotyping at codon 16 of the beta2-AR by RFLP-PCR assay. The effects of a 4-week monotherapy with formoterol (12 μg BID) were tested on the peak expiratory flow (PEF) variability and the forced expiratory volume in 1 sec (FEV1) slope of the dose-response curve to salbutamol. Variability in PEF significantly increased during the 4-week treatment period in 14 patients with GlyGly16, but not in 15 patients with ArgArg16 and ArgGly16(P=0.032). The FEV1 slope of the dose-response curve to salbutamol decreased after the 4-week treatment period in GlyGly16, but not in pooled ArgArg16 and ArgGly16 patients. This study provides preliminary evidence that tolerance to formoterol develops more frequently in asthmatics with GlyGly16 genotype. If confirmed in a larger population, this finding might be useful in choosing the bronchodilator therapy on the basis of genetic polymorphism of the beta2-AR.

Stratifying a Risk for an Increased Variation of Airway Caliber among the Clinically Stable Asthma

Recently, correlations of peak expiratory flow (PEF) variation have been shown to facilitate the prediction of later asthma symptoms and exacerbations. However, it has not been fully examined whether or not any patient characteristics are associated with the residual airway lability in treated asthmatics. The objective of this study is to examine a predictive marker for increased variation of PEF in patients with clinically stable asthma. We studied 297 asthmatic patients who were monitored for PEF twice a day. Asthma Control Questionnaire (ACQ), spirometry, and exhaled nitric oxide fraction (FENO) were measured. After the assessment of baseline values, PEF measuring was continued and associations between these clinical markers and later variation of PEF over a week (Min%Max) were investigated. 17.5% of the subjects showed increased PEF variability (Min%Max < 80%). ACQ, forced expiratory volume in 1 s % of predicted (%FEV1), and FENO were identified as independent predictors of Min%Max < 80%. An ACQ ≥ 0.4 yielded 96% sensitivity and 59% specificity, a %FEV1 ≤ 85% yielded 62% sensitivity and 89% specificity, and a FENO ≥ 40 ppb yielded 75% sensitivity and 90% specificity for identifying the subjects with high variability in PEF. When we combine %FEV1 ≤ 85% and FENO ≥ 40 ppb, this index showed the highest specificity (98%) for increased PEF variability. These results indicate that ACQ, %FEV1 and FENO can stratify the risk for increased variation in airway caliber among patients with stable asthma. This may help identify subjects in whom further monitoring of lung function fluctuations is indicated.

Markers that can Reflect Asthmatic Activity before and after Reduction of Inhaled Corticosteroids: A Pilot Study

Evaluation of airway inflammation is important in achieving adequate dosing of inhaled corticosteroids (ICS) for treating bronchial asthma. However, there is no evaluation tool that can be used in clinical settings. We examined biomarkers that can precisely reflect airway inflammation when ICS are decreased in stable asthmatic patients. This was a 12-week, single-arm, open-label clinical study performed at a single university hospital. Twenty-five patients (6 male and 19 female) with stable asthma were included in this study. We investigated whether the levels of nitrite and nitrate in exhaled breath condensate (EBC) increase after ICS reduction. We also investigated whether blood eosinophils, serum immunoglobulin E (IgE), high-sensitivity C reactive protein (hs-CRP), interleukin (IL)-13, IL-17, and periostin are different before and after ICS reduction. Peak expiratory flow (PEF), pulmonary function tests, asthma control test (ACT), and asthma quality of life questionnaire (AQLQ) were also examined. We considered an unscheduled hospital visit due to asthmatic symptoms and decline in average PEF over one week by more than 10% to indicate disease instability, and compared patients with stable and unstable disease for analysis. Unstable status was detected in 5 patients. Age, sex, asthma duration, ACT and AQLQ scores, and the level of serum IgE did not differ between stable and unstable groups. In the unstable group, the total concentration of nitrite and nitrate at the last visit was 9.84 (6.65–11.24) μM. Surprisingly, this was similar to the concentration at the first visit (5.58 (2.94–17.29) μM). Serum periostin before ICS reduction (141.9 [107.7–147.7] pg/mL) was higher in the unstable group than in the stable group (91.5 [78.75–103.5] pg/mL). The unstable group had a higher peripheral blood eosinophil count and wider diurnal variation of PEF at the first visit compared to the stable group. Higher eosinophils in peripheral blood and wider diurnal variation of PEF were predictive markers for unstable disease after ICS reduction. Serum periostin is another candidate for the predictive marker.

Asthma Severity and Environmental Health Risk Factor among Asthmatic Primary School Children in the Selected Areas

Problem statement: The purpose of this study was to assess the severity of asthma and associated risk factors among asthmatic primary school children in the selected urban, industrial and rural areas of Selangor and Kuala Lumpur. Approach: A total of 207 respondents were involved in this study, in which 87 were children from the urban areas, 67 children were from the industrial areas and another 53 children were from rural areas. The selection of respondents was based on purposive sampling method, where only asthmatic children who had been diagnosed by physicians were involved. Health records of the children were obtained from the school administration office. Respondents were children from Standard 2 to Standard 5, with informed consent from their parents. A modified ISAAC Questionnaire translated into the Malay language was administered to the children and then completed by the parents. Peak Expiratory Flow (PEF) readings were measured using a peak flow meter Mini Weight Model AFS CE 0120 on Monday, Wednesday and Friday before and after the school hour. Continuous ambient air pollutants (PM10, CO, SO2 and NO2) levels were obtained from the Department of Environment. Results: Results showed significant influence of PEF reading before and days in the week, on the PEF reading after school among respondents. The severity of asthma among respondents was classified according to the PEF variability, day and night symptoms as well as the respiratory scores. Most of the children had mild and moderate asthma. Statistics showed that PM10 and allergy to pollen significantly influenced the asthma severity among respondents. Conclusion: The air pollutants in term of PM10 which may contain pollen were higher in the urban and industrial areas. This study provided a confirmatory evidence that the asthmatic children who live in urban and industrial areas have greater risk of developing severe asthma.

Determinants of asthma control and quality of life in stable asthma: evaluation of two new cough provocation tests

Asthma control and quality of life are poorly associated with traditional asthma biomarkers. In the present study, we evaluated two new cough provocation tests in this respect. Asthma Control Questionnaire and Leicester Cough Questionnaire were completed by 36 stable asthmatics. Cough provocation tests with hypertonic saline and isocapnic hyperpnoea of dry air were performed, as well as spirometry, ambulatory peak expiratory flow (PEF) monitoring and exhaled nitric oxide (eNO) measurement. Leicester Cough Questionnaire score correlated closely with cough responsiveness to hypertonic saline and isocapnic hyperpnoea (R = -0.66, P < 0.001 and R = -0.49, P = 0.002, respectively). Asthma Control Questionnaire score also correlated with the cough responsiveness to these tests (R = 0.52, P = 0.001 and R = 0.43, P = 0.008, respectively). Forced expiratory volume in 1 s (%predicted), diurnal PEF variation and eNO did not correlate with cough-related quality of life but showed some association with asthma control. There was a significant correlation between Leicester Cough Questionnaire and Asthma Control Questionnaire (R = -0.54, P = 0.001). Asthma control and cough-related quality of life are more closely associated with cough responsiveness to the investigated cough provocation tests than to eNO and traditional indices of bronchial obstruction. Cough is a major contributor to poor asthma control.

Effect of mindfulness training on asthma quality of life and lung function: a randomised controlled trial

BackgroundThis study evaluated the efficacy of a mindfulness training programme (mindfulness-based stress reduction (MBSR)) in improving asthma-related quality of life and lung function in patients with asthma.MethodsA randomised controlled trial...

Associated demographics of persistent exhaled nitric oxide elevation in treated asthmatics

The fraction of exhaled nitric oxide (FENO) is reduced by anti-inflammatory treatment in asthma. However, the FENO level is also regulated by individual demographics and there is considerable variation among clinically stable patients. We hypothesized that some demographics may be responsible for persistent FENO elevation despite inhaled corticosteroids (ICS) therapy in asthma. This was a prospective observational study. We initially screened 250 stable asthmatics and determined the FENO cut-off point for identifying poorly controlled asthma defined by one of the following criteria: Asthma control test <20, or forced expiratory volume in one-second % of predicted <80%, or peak expiratory flow variability <80% (Study 1). After 12-weeks, 229 patients who maintained high or low FENO were selected and the independent factors which might contribute to a high FENO were examined (Study 2). A FENO level >39.5 p.p.b. yielded 67% sensitivity and 76% specificity for identifying the patients with poorly controlled asthma. The persistent high FENO group (≥ 40 p.p.b.) was more likely to be ex-smokers, to show evidence of atopy (positive specific IgE, higher serum IgE and blood eosinophils), and to have allergic comorbidities. Especially, past smoking history, blood eosinophils, and chronic rhinosinusitis were identified to be independent predictors of high FENO. Neither the dose of ICS nor other medication use showed any difference between the groups. These results suggested that past smoking history, blood eosinophilia, and chronic rhinosinusitis are involved in the persistent airway inflammation detected by FENO. Although their relative contributions on FENO values should be further quantified, clarification of the features of the subjects with high FENO might provide clues for adjustment of the treatment approach in asthma.

Asthma Control Test (ACT): Comparison with Clinical, Functional, and Biological Markers of Asthma Control

Background. Asthma Control Test (ACT) is a simple tool for assessing the level of asthma control in clinical practice, and it has been validated in comparison with a general clinical assessment of asthma control, including forced expiratory volume in the first second (FEV1). Objective. To evaluate the relationship between ACT score and clinical and functional findings of asthma control and biomarkers of airway inflammation. Methods. A total of 68 asthmatic patients observed in our asthma clinic (33 regularly treated with inhaled corticosteroids (ICS) and 35 ICS-naïve) filled ACT questionnaire and underwent the following measurements: (a) FEV1 before and after salbutamol; (b) exhaled nitric oxide; (c) bronchial hyperresponsiveness to methacholine; (d) sputum eosinophil count; and (e) daytime and nighttime symptoms, rescue salbutamol, and twice-daily peak expiratory flow (PEF) recording on a 4-week diary card. Results. ACT score significantly correlated with symptom score, rescue medication use, and PEF variability, but not with FEV1, FEV1 reversibility, and markers of airway inflammation, which could not distinguish controlled from uncontrolled patients according to ACT, regardless of ICS treatment. Conclusion. ACT score is a valid tool to simply assess the current level of asthma control in terms of symptoms, rescue medication use, and PEF variability. Pulmonary function and biomarkers of airway inflammation are not related to the clinical asthma control as assessed by ACT and may represent additional measurements potentially useful in asthma management.

Airway obstruction lability helps distinguish levels of disease activity in asthma

Classifying disease activity in asthma relies on clinical and physiological variables, but these variables do not capture all aspects of asthma that distinguish levels of disease activity. We used data from two pivotal trials of montelukast in asthma to classify disease activity as "high" or "low". We performed a principal component analysis (PCA) of disease activity using 21 efficacy outcome variables, including several novel derived outcome variables reflecting clinical and airway obstruction lability. Then we performed discriminant analysis (DA) based on disease activity classification. PCA revealed 6 factors (daytime asthma control, nighttime-predominant asthma control, airway obstruction, exacerbations, clinical lability, airway obstruction lability) that explained 76% of the variance between outcome variables. Although airway obstruction lability (comprising both diurnal variability in peak expiratory flow and diurnal variability in β-agonist use) accounted for only 6% of the explained variance in PCA, in DA it was more accurate (canonical coefficient 0.75) than traditional measures of asthma severity such as obstruction (-0.54) and daytime control (-0.56) in distinguishing between high and low disease activity. We conclude that airway obstruction lability, a parameter not typically captured in clinical trials, may contribute to more complete assessment of asthma disease activity and may define an emerging clinical target of future therapy.

Effect of Exposure and Sensitization to Indoor Allergens on Asthma Control Level

Reducing risk factors, such as exposure to allergens, and stepwise pharmacotherapy to achieve and maintain control of asthma are the mainstay of asthma care. The purpose of this study was to clarify the effect of exposure and sensitization to indoor allergens, including house dust mites, cats, and dogs, on the asthma control level. Dust samples were collected from the mattresses of 101 adult asthma patient homes and the Dermatophagoides mite group 1 (Der 1), Fel d 1, and Can f 1 concentrations were measured using ELISA. Sensitization was determined by positive specific IgE antibodies. The Asthma Control Test (ACT), lowest peak expiratory flow (PEF) during 1 week expressed as a percentage of the highest PEF (Min%Max PEF), and spirometry were measured for the assessment of asthma control. Univariate and multivariate regression analyses were used to assess the relationships. Sixty-nine patients were exposed to high levels (>10μg/g dust for Der 1 and Can f 1 and >8μg/g dust for Fel d 1) of 1 or more allergens and 39 patients were sensitized to at least one allergen. Multivariate logistic regression analyses revealed that the FEV(1) (% of predicted value) was associated with low ACT scores (≤19) and that the number of highly exposed allergens and inhaled corticosteroid dose were associated with a low level of Min%Max PEF (<80%). The level of exposure to multiple indoor allergens, but not sensitization, is associated with the asthma control level determined by PEF variation.

Exhaled breath 8-isoprostane as a marker of asthma severity.

IntroductionOxidative stress is a non-specific feature of airway inflammation in asthmatics. 8-Isoprostane (8-IP), a prostaglandin-F2α isomer, is a relatively new marker of oxidative stress and may be measured in exhaled breath condensate (EBC) of patients with asthma. This research study aimed to evaluate the usefulness of EBC 8-IP as a marker of severity and control of severe adult asthma.Material and methodsTwenty-seven severe, never-smoking asthmatics were studied. According to positive or negative reversibility testing, this group was subdivided into reversible and irreversible asthma groups. All participants were observed for 8 weeks during which they completed daily diary observations including day and night symptoms, number of awakenings, peak expiratory flow (PEF) variability, daily rescue medication usage and oral steroids consumption. They attended the clinic 3 times and on these occasions spirometry assessments, EBC collection and asthma control tests (ACT) were done. Two control groups were included: 11 healthy never-smokers and 16 newly diagnosed and never-treated, non-smoking mild asthmatics.ResultsThere were no statistically significant differences between severe asthma and healthy control or never-treated asthma groups in concentrations of EBC 8-IP (median and interquartile range: 4.67; 2.50-27.92 vs. 6.93; 2.5-12.98 vs. 3.80; 2.50-10.73, respectively). No correlations were found between EBC 8-IP and asthma control parameters, such as ACT results, night and day symptoms, consumption of rescue medication, percentage of days free of oral steroids, PEF diurnal variation, lung function test results, forced expiratory volume in the 1 s reversibility, and markers of systemic inflammation.ConclusionsOur study results suggest that EBC 8-IP measurements are not useful for asthma monitoring.

Acupuncture in children and adolescents with bronchial asthma: A randomised controlled study

This randomised controlled trial evaluates the immediate effects of acupuncture as an add-on therapy in in-patient rehabilitation of children and adolescents with bronchial asthma. In a pre-post design, the severity of symptoms, lung function, illness-specific quality of life (Paediatric Asthma Quality of Life Questionnaire - PAQLQ) and general and asthma-specific level of anxiety (State-Trait Anxiety Inventory for Children - STAIC) were investigated in 46 acupuncture and 47 control patients. In addition to asthma sports, climate therapy and behavioural training, the intervention group received acupuncture treatment with a standardised needle pattern (12 × 30 min.). With acupuncture, the peak expiratory flow variability differs significantly (p<0.01) from that of the control patients' group. Moreover, the acupuncture group differs significantly in their rehabilitation response at the time of discharge concerning perceived anxiety (STAIC-S). The lung function tests do not present differences between groups. After additional acupuncture, amelioration of peak expiratory flow variability and anxiety can be shown, without any difference in objective lung function tests and quality of life between study groups. Further studies might evaluate the effects of acupuncture on childhood asthma in an outpatient setting.

Differentiating occupational asthmatics from non-occupational asthmatics and irritant-exposed workers

Serial peak expiratory flow (PEF) records have been recommended as a first-line investigation in workers suspected as having occupational asthma (OA). To determine which PEF variability index best differentiates workers with OA from non-occupational asthmatics and unaffected irritant-exposed workers. PEF was measured at least four times daily for at least 3 weeks in three groups of subjects: (i) forty healthy grain-exposed farmers and dockers, (ii) forty-two consecutive workers with independently confirmed OA and (iii) forty-eight non-occupational asthmatics. Indices of PEF variability were compared between groups. The difference in mean PEF between rest and work periods best separated the occupational asthmatic workers from the others. The upper 95% confidence limit of this index for grain-exposed workers was 2.8% of predicted PEF (16 l/min) and 3.3% (15 l/min) for non-occupational asthmatics. Sensitivity for diagnosing OA using this index was 70%. An increase in diurnal variation on workdays of >7% had a sensitivity of only 27% for the diagnosis of OA. The difference between maximum PEF on workdays and minimum PEF on rest days had a sensitivity of <10% against non-occupational asthmatic controls. Difference in mean PEF between workdays and rest days is the best simple index for differentiating subjects with OA from those with non-OA or irritant-exposed healthy subjects. Differences >16 l/min are unlikely to be due to significant irritant exposure in healthy workers.

Nocturnal asthma monitoring by chest wall electromyography

RationalePatients with suboptimal asthma control often have nocturnal symptoms which wake them, causing sleep fragmentation.ObjectivesIt was hypothesised that symptomatic patients were more accurately identified by measuring respiratory effort using chest...

Relationship Between “Morning Dipping” in Peak Expiratory Flow (PEF) or Peak Expiratory Flow Variability (PEFV) and Study Withdrawals: Post Hoc Analysis of a Randomized 12-Week Study in Patients with Moderate to Severe Asthma

RATIONALE: Early study discontinuations may indicate poor asthma control. We assessed the relationship between morning PEF dips or PEFV and study discontinuation due to an asthma event based on prespecified criteria (lung function, rescue medication use, awakenings, need for healthcare utilization).METHODS: This post hoc analysis of a randomized, double-blind 12-week study (NCT00652002 [Drugs. 2006;66:2235-54]) included moderate-severe persistent asthma patients receiving placebo and as-needed albuterol with ≥2 weeks of observation (first 2 weeks censored to wash out any inhaled corticosteroid run-in effects). Patients recorded morning and evening PEF daily via e-diary. Morning dipping was defined as percent decrease in morning versus evening PEF, averaged over the treatment period. PEFV was calculated as (maximal PEF-minimum PEF)/mean PEF over the treatment period. Associations between percent morning dipping or PEFV and study withdrawals were assessed.RESULTS: Of 125 placebo patients, 70 were included in this analysis, of whom 27% did not demonstrate morning dipping as defined; 64% and 9% had morning dipping <7.5% and ≥7.5%, respectively. Most patients (69%) had PEFV <7.5%. Compared with completers (n=47 [67% of patients]), patients with early withdrawal (n=23 [33% of patients]) had twice the mean percent morning dipping (3.9% vs 1.7%) and PEFV (10.4% vs 5.2%). The most commonly met discontinuation criterion was decreased forced expiratory volume in 1 second.CONCLUSIONS: Increased morning dipping and PEFV was associated with premature discontinuation from the placebo arm of a clinical trial due to predefined asthma event. These findings support the value of morning dipping and PEFV as relevant asthma control indicators. RATIONALE: Early study discontinuations may indicate poor asthma control. We assessed the relationship between morning PEF dips or PEFV and study discontinuation due to an asthma event based on prespecified criteria (lung function, rescue medication use, awakenings, need for healthcare utilization). METHODS: This post hoc analysis of a randomized, double-blind 12-week study (NCT00652002 [Drugs. 2006;66:2235-54]) included moderate-severe persistent asthma patients receiving placebo and as-needed albuterol with ≥2 weeks of observation (first 2 weeks censored to wash out any inhaled corticosteroid run-in effects). Patients recorded morning and evening PEF daily via e-diary. Morning dipping was defined as percent decrease in morning versus evening PEF, averaged over the treatment period. PEFV was calculated as (maximal PEF-minimum PEF)/mean PEF over the treatment period. Associations between percent morning dipping or PEFV and study withdrawals were assessed. RESULTS: Of 125 placebo patients, 70 were included in this analysis, of whom 27% did not demonstrate morning dipping as defined; 64% and 9% had morning dipping <7.5% and ≥7.5%, respectively. Most patients (69%) had PEFV <7.5%. Compared with completers (n=47 [67% of patients]), patients with early withdrawal (n=23 [33% of patients]) had twice the mean percent morning dipping (3.9% vs 1.7%) and PEFV (10.4% vs 5.2%). The most commonly met discontinuation criterion was decreased forced expiratory volume in 1 second. CONCLUSIONS: Increased morning dipping and PEFV was associated with premature discontinuation from the placebo arm of a clinical trial due to predefined asthma event. These findings support the value of morning dipping and PEFV as relevant asthma control indicators.

Relationship of endotoxin and tobacco smoke exposure to wheeze and diurnal peak expiratory flow variability in children and adolescents

The relationship between endotoxin exposure and asthma severity (wheeze and airways obstruction) is not well described. The effects of endotoxin and tobacco smoke exposure on self-reported wheeze and diurnal PEF variability (DV-PEF) were examined in children aged 6-18 years with asthma or wheeze. A cross-sectional study was performed in a rural area. From this study, children who reported wheeze in the previous 12 months or a physician diagnosis of asthma (n = 98) were selected for a case-control study. These subjects, who were the basis for the present analysis, completed: (i) a home environmental assessment, including dust collection to measure endotoxin levels: (ii) a clinic visit, including saliva collection to measure cotinine levels; and (iii) 2 week monitoring of twice daily symptom records, including wheeze, and PEF to calculate DV-PEF. Among these children, 22.4% reported wheeze during the monitoring period. Greater DV-PEF was associated with higher endotoxin loads in play areas (P < 0.05). The association between salivary cotinine levels and high DV-PEF was modified by gender. In females, higher cotinine levels were associated with an increased risk of high DV-PEF compared with lower cotinine levels (P < 0.05), but this was not observed among males. Higher endotoxin exposure was associated with greater DV-PEF among children with asthma or wheeze. While previous studies have suggested that endotoxin exposure protects against the development of asthma, individuals with the disease should avoid high exposure levels to limit exacerbations. The effect of tobacco smoke exposure on lung health may differ between male and female children.

Induced Sputum Substance P in Children with Difficult-to-Treat Bronchial Asthma and Gastroesophageal Reflux: Effect of Esomeprazole Therapy

Objectives. To assess the induced sputum substance P (ISSP) levels in children having difficult-to-treat asthma (DA) with and without gastroesophageal reflux (GER). We aimed also to evaluate the association of GER with childhood DA, relationship of GER severity with childhood asthma control test (C-ACT), FEV1, peak expiratory flow (PEF) variability, and ISSP. Finally, we tried to evaluate esomeprazole treatment effect on C-ACT and FEV1 in children with DA. Methods. Spirometry, C-ACT, upper gastrointestinal endoscopy, and ISSP measurement were done for children with DA compared to healthy controls. Results. ISSP was high in DA with higher levels in the group having associated GER. In the latter group, ISSP and C-ACT improved significantly after esomeprazole treatment while FEV1 and PEF variability did not improve. Reflux severity was positively correlated with ISSP and negatively correlated with FEV1. Conclusions. GER was found in 49% of our patients with childhood DA. Very high ISSP levels in children with DA may be used as a marker for presence of GERD. Esomeprazole therapy improved asthma symptoms but did not improve lung function.

Pulmonary manifestations of polyvinyl chloride exposure

There is currently no national data on the effects of polyvinyl chloride (PVC) exposure on pulmonary function. In this study we recruited workers and administrative staff from two PVC plants between July 2008 and July 2009. A questionnaire, pulmonary function tests, carbon monoxide diffusion capacity, and peak flows were recorded. Particulate matter analyses were performed by the Adana Central Laboratory of the Directorate of Occupational Health and Safety. Data were analyzed with SPSS 13.0 software. Nine of the 147 subjects were female. The incidence of a cough was more common in the administrative group. Of the study population, 59.1% were smokers. Tobacco addiction significantly increased cough and dyspnea [OR= 1.10 (1.00-1.20, 95% CI) p= 0.007 and OR= 1.08 (1.02-1.14, 95% CI), p= 0.008, respectively]. Dust exposure was correlated with the incidence of a cough [OR= 0.20 (0.04-0.80, 95% CI) p= 0.008]. The period of work correlated with sputum production [OR= 1.00 (1.00-1.02, 95% CI) p= 0.044]. The FVC% was significantly higher in the administrative group, and FEV1/FVC and DLCO were higher in the exposed group. Tobacco addiction increased the risk of airflow limitation, as evaluated by FEV1/FVC < 70% and FEF25-75 < 50% [OR= 1.15 (1.06-1.25, 95% CI) p= 0.001 and OR= 1.09 (1.02-1.17, 95% CI) p= 0.010, respectively]. Tobacco addiction and increasing duration of work had a negative influence on DLCO in the exposed group (r= -0.270, p= 0.025 and r= -0.210, p= 0.037). In the exposed group PEF variability was significantly greater on workdays, compared with rest days. This study shows that tobacco consumption has a greater affect on the airways than PVC dust exposure. A median of 36 months exposure to PVC dust had no significant impact on pulmonary function parameters, except for DLCO and PEF variability.

Relationship Between Comorbidity and Asthma Control

Introduction The coexistence of potentially aggravating processes is common in asthmatics, particularly in patients with difficult control. The primary aim of this study is to ascertain whether comorbidity is more common in uncontrolled patients. As a secondary aim, we propose to evaluate the correlation between the asthma control test (ACT) and the fraction of exhaled nitric oxide (FENO). Patient and methods A prospective, observational study comparing the function and clinical picture of two groups of asthmatics: controlled (ACT≥20) and uncontrolled (ACT<20). They were all assessed for, smoking, rhinosinusitis, obesity, anxiety, depression, vocal chord dysfunction, gastro-oesophageal reflux (GORD), allergic bronchopulmonary aspergillosis (ABPA), COPD and nasal polyps. Results A total of 50 patients with controlled asthma and 102 with sub-optimal control were included. The patients with an ACT≥20 had better lung function, less variation in PEF, less bronchial hyper-reactivity and lower FENO values. Comorbidities were found in 95% of the controlled asthmatics and in 97% of the uncontrolled. Only the presence of nasal polyps, GORD and ABPA was more frequent in the uncontrolled group. However, the simultaneous presence of 3 or more comorbidity factors was significantly more frequent in patients with sub-optimal control ( P=.01). There was no significant correlation between the FENO and the ACT values (rho=−0.08; P=.32). Conclusions Aggravating comorbidities are more common in patients with sub-optimal control. There was no correlation between the FENO and the ACT values.