Small Airway Dysfunction in Cough Variant Asthma: Prevalence, Clinical, and Pathophysiological Features

Introduction: Small airway dysfunction (SAD) commonly presents in patients with classic asthma, which is associated with airway inflammation, disease severity, and asthma control. However, the prevalence of SAD, its relationship with cough severity and airway inflammation, and its development after antiasthmatic treatment in patients with cough variant asthma (CVA) need to be clarified. This study aimed to investigate the prevalence of SAD and its relationship with clinical and pathophysiological characteristics in patients with CVA and the change in small airway function after antiasthmatic treatment.Methods: We retrospectively analyzed 120 corticosteroid-naïve patients with CVA who had finished a standard questionnaire and relevant tests in a specialist cough clinic, such as cough visual analog scale (VAS), differential cells in induced sputum, fractional exhaled nitric oxide (FeNO) measurement, spirometry, and airway hyper-responsiveness. Information of 1-year follow-up was recorded in a part of patients who received complete cough relief after 2 months of treatment. SAD was defined as any two parameters of maximal mid-expiratory flow (MMEF)% pred, forced expiratory flow at 50% of forced vital capacity (FEF50%) pred, and forced expiratory flow at 75% of forced vital capacity (FEF75%) pred measuring <65%.Results: SAD occurred in 73 (60.8%) patients with CVA before treatment. The patients with SAD showed a significantly longer cough duration (24.0 vs. 6.0, p = 0.031), a higher proportion of women (78.1 vs. 59.6%, p = 0.029), older mean age (41.9 vs. 35.4, p = 0.005), and significantly lower forced expiratory volume in 1 s (FEV1%) pred, FEV1/FVC, MMEF% pred, FEF50% pred, FEF75% pred, PEF% pred, and PD20 (all p < 0.01) as compared with patients without SAD. There were no significant differences in cough VAS, sputum eosinophils count, FeNO, and TIgE level between patients with SAD and those without SAD. Among 105 patients who completed 2 months of antiasthmatic treatment and repeatedly experienced spirometry measurement, 57 (54.3%) patients still had SAD, despite a significant improvement in cough VAS, sputum eosinophils, FeNO, FEF50% pred, and PEF% pred (all p < 0.01). As compared with patients without SAD, patients with SAD showed no significant differences in the relapse rate (50.0 vs. 41.9%, p = 0.483) and wheeze development rate (10.4 vs. 0%, p = 0.063) during the follow-up.Conclusions: Small airway dysfunction occurred in over half of patients with CVA and persisted after short-term antiasthmatic treatment, which showed distinctive clinical and pathophysiological features.

Predictors of Airway Hyperresponsiveness in Symptomatic Children with Normal Spirometry and Suspicious of Possible Asthma

<b><i>Background:</i></b> Asthma diagnosis may be challenging particularly in patients with mild symptoms without an obstructive pattern in spirometry. Detection of airway hyperresponsiveness (AHR) by a positive methacholine challenge (MCC) is still an important diagnostic tool to confirm the presence of asthma with reasonable certainty. However, it is time consuming and could be exhausting for patients. We aimed to identify the predictive factors for AHR in children with respiratory symptoms without obstructive pattern in spirometry. <b><i>Methods:</i></b> Data from children who had undergone MCC were analyzed retrospectively. The demographic features of patients along with laboratory results were collected. <b><i>Results:</i></b> A total of 123 children with a median age of 10.5 years were enrolled. AHR was detected in 81 children (65.8%). The age of the children with AHR was significantly younger. The prevalences of aeroallergen sensitization, nocturnal cough, wheezing, and a baseline forced expiratory flow at 75% of vital capacity (FEF₇₅) &#x3c;65% were significantly more frequent in children with AHR. Multivariate logistic regression analysis revealed age, ever wheezing, nocturnal cough, tree pollen allergy, and FEF₇₅ &#x3c;65% as independent predictors of AHR. A weighted clinical risk score was developed (range, 0–75 points). At a cutoff point of 35, the presence of AHR is predicted with a specificity of 90.5% and a positive predictive value of 91.5%. <b><i>Conclusion:</i></b> In children suspected of having asthma, but without an obstructive pattern in the spirometry, combining independent predictors, which can be easily obtained in clinical practice, might be used to identify children with AHR.

The Effect of an Olympic Distance Triathlon on Pulmonary Diffusing Capacity and its Recovery 24 Hours Later

The Olympic distance triathlon includes maximal exercise bouts with transitions between the activities. This study investigated the effect of an Olympic distance triathlon (1.5-km swim, 40-km bike, 10-km run) on pulmonary diffusion capacity (DLCO). In nine male triathletes (age: 24 ± 4.7 years), we measured DLCO and calculated the DLCO to alveolar volume ratio (DLCO/VA) and performed spirometry testing before a triathlon (pre-T), 2 hours after the race (post-T), and the day following the race (post-T-24 h). DLCO was measured using the 9-s breath-holding method. We found that (1) DLCO decreased significantly between pre- and post-T values (38.52 ± 5.44 vs. 35.92 ± 6.63 ml∙min-1∙mmHg-1) (p < 0.01) and returned to baseline at post-T-24 h (38.52 ± 5.44 vs. 37.24 ± 6.76 ml∙min-1∙mmHg-1, p > 0.05); (2) DLCO/VA was similar at the pre-, post- and post-T-24 h DLCO comparisons; and (3) forced expiratory volume in the first second (FEV1) and mean forced expiratory flow during the middle half of vital capacity (FEF25-75%) significantly decreased between pre- and post-T and between pre- and post-T-24-h (p < 0.02). In conclusion, a significant reduction in DLCO and DLCO/VA 2 hours after the triathlon suggests the presence of pulmonary interstitial oedema. Both values returned to baseline 24 hours after the race, which reflects possible mild and transient pulmonary oedema with minimal physiological significance.

Assessment of Metal Concentrations and Associations with Pulmonary Function among Children with Asthma in Chicago, Illinois

Individuals living in areas with the potential for elevated metal exposure from industrial sources may have reduced pulmonary function. We evaluated cross-sectional associations of toenail concentrations of 17 metals within a community area of residence and asthma control in 75 children, and pulmonary function measures [forced expiratory volume in one second (FEV1; liters), forced vital capacity (FVC; liters), FEV1 to FVC ratio (FEV1:FVC), and mid-exhalation forced expiratory flow rate (FEF 25–75%; liters/second)], in a subsample of 39 children with diagnosed asthma in Chicago, Illinois. Linear regression models were used to estimate adjusted regression coefficients and standard errors (SE) for the associations between ≥ median versus <median metal exposures and natural log-transformed (ln) pulmonary function test parameters. Toenail levels of cadmium, cobalt, iron, manganese, and vanadium were higher among children residing near an industrial corridor than those in a comparison community. Copper concentrations were inversely associated with lnFEV1 (β = −0.10, SE = 0.04, p = 0.01), lnFEV1:FVC (β = −0.07, SE = 0.03, p = 0.02) and lnFEF 25–75% (β = −0.25, SE = 0.09, p = 0.01); manganese concentrations were inversely associated with lnFEV1 (β = −0.11, SE = 0.04, p = 0.01), lnFEV1:FVC (β = −0.07, SE = 0.03, p = 0.02), and lnFEF 25–75% (β = −0.28, SE = 0.10, p = 0.004), and vanadium concentrations were inversely associated with lnFEV1 (β = −0.08, SE = 0.04, p = 0.05) and lnFVC (β = −0.07, SE = 0.03, p = 0.03). Nickel and copper were associated with uncontrolled asthma (OR = 6.8; 95% CI 2.0, 22.8 and OR = 4.6; 95% CI 1.0, 21.0, respectively). These data suggest that selected metal exposures may be associated with impaired pulmonary function parameters and reduced asthma control among children with preexisting asthma.

Comparative analysis of respiratory health profile among female beedi and non-beedi workers in a district of West Bengal

Background: Beedi workers are more prone to develop chronic respiratory diseases over time. Aims and Objectives: The present research aimed to investigate and compare the respiratory health profile and the factors associated among the beedi workers and non-beedi workers. Materials and Methods: An analytical, community based, cross sectional study was conducted among 60 female beedi and non-beedi workers. Multistage sampling was used to select three wards out of twenty wards under a municipality of the study district. After interview with a pre-designed structured questionnaire, the respondents were examined clinically and pulmonary function test was done using a portable spirometer. Results: All beedi workers were married and 23.3% were illiterate. Most of them had 1to 10 years exposure. Half of them initiated their work between 11 to 20 years. Rate of tobacco smoking, obesity, hypertension, asthma, diabetes was high among beedi workers. Forced Vital Capacity, Forced Expiratory Flow 25-75 and Peak Expiratory Flow Rate were significantly more among non-beedi workers. Forced Expiratory Volume in 1st second was more among non-beedi workers but FEV1/FVC ratio was same for both the group. Conclusion: Significantly better respiratory health profile of non-beedi workers have reflected beedi binding as a reason behind chronic respiratory disease. Therefore, awareness generation session regarding occupation based adverse effects and safety measures must be conducted at regular interval to make the working condition favorable.

Dose–Response Relationship between Environmental Exposure to Nickel and Pulmonary Function in the Korean General Population Aged 40 or Older

Nickel is a well-known skin allergen; however, few studies to date have investigated the association between nickel exposure and lung function impairment. The present study, therefore, evaluated the relationship between blood nickel concentrations and lung function profiles in the Korean general population (n = 1,098). Dose–response relationships between blood nickel quartiles and pulmonary function were assessed by sex in multivariate models, after adjustment for potentially confounding factors such as age, height, and smoking status. Quartiles of blood nickel concentrations were significantly associated with markers of pulmonary function in Korean men, such as forced expiratory volume in 1 second (FEV1) and forced expiratory flow 25–75% (FEF25–75%). Relative to the first quartile, the estimated coefficients (standard error (SE)) of blood nickel levels for FEV1 in the third and fourth quartiles of Korean men were −126.6 mL (59.1) and −138.5 mL (59.8), respectively (p < 0.05). Relative to the first quartile, the estimated coefficients (SE) of blood nickel levels for FEF25–75% in the second and fourth quartiles were −244.9 mL (109.5) and −266.8 mL (111.5), respectively (p < 0.05). Dose–response relationships were observed between quartiles of blood nickel concentrations and the pulmonary function markers FEV1 and FEF25–75% in Korean men aged 40 or older.

Effect of Glycated Hemoglobin (HbA1c) and Duration of Disease on Lung Functions in Type 2 Diabetic Patients

Diabetes mellitus is a highly challenging global health care problem. This study aimed to assess the effect of glycated hemoglobin (HbA1c) and duration of diabetes on lung function in type 2 diabetic patients and assess whether duration or high HbA1c is more noxious to damage the lung functions. A total of 202 participants, 101 patients with type 2 diabetes mellitus (T2DM), and 101 age-, gender-, height-, and weight-matched controlled subjects were recruited. The HbA1c was measured through a clover analyzer, and lung function test parameters were recorded by spirometry. The results revealed a significant inverse correlation between HbA1c and Vital Capacity (VC) (r = −0.221, p = 0.026), Forced Vital Capacity (FVC) (r = −0.261, p = 0.008), Forced Expiratory Volume in First Second (FEV1) (r = −0.272, p = 0.006), Forced Expiratory Flow 25% (FEF-25%) (r = −0.196, p = 0.050), Forced Expiratory Flow 50% (FEF-50%) (r = −0.223, p = 0.025), and Forced Expiratory Flow 75% (FEF-75%) (r = −0.169, p = 0.016). Moreover, FEV1 (p = 0.029), FEV1/FVC% (p = 0.006), FEF-50% (p = 0.001), and FEF-75% (p = 0.003) were significantly lower in the diabetic group with duration of disease 5–10 and >10 years compared to the control group. The overall results concluded that high HbA1c or uncontrolled diabetes mellitus has a more damaging effect on lung function impairment compared to the duration of diabetes mellitus. Physicians must regularly monitor the HbA1c level while treating diabetic patients, as good glycemic control is essential to minimize the complications of DM, including lung function impairment in patients with T2DM.

The effect of brace treatment on pulmonary functions in adolescent idiopathic scoliosis: An 8-month follow-up study

BACKGROUND: The instant effect of a brace on pulmonary functions of patients with adolescent idiopathic scoliosis (AIS) is known. However, the permanent effects of its regular use are still unclear. OBJECTIVE: This study aimed to determine whether a brace in patients with AIS had a permanent effect on respiratory functions. METHODS: Fifteen patients with a mean age of 13.2 ± 1.6 years, and a major Cobb angle of 25.8∘± 7.7∘ participated in this study. Lung volumes and respiratory muscle strength were measured with and without thoracolumbosacral brace, at the end of first month and follow-up period after the patients started using the brace for 23 hours daily. RESULTS: When the brace was on, the forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), ratio of FEV1/FVC, peak expiratory flow, and forced expiratory flow between 25% and 75% of vital capacity values were found to be lower at both first month and follow-up. After the follow-up, the measurement results did not differ from the results of the first month. CONCLUSIONS: The brace had a momentary restrictive effect on patients with AIS. However, it did not cause a permanent change in pulmonary functions after the 8-month follow-up.

Diffuse cystic lung disease in sickle cell anaemia: a series of 22 cases and a case–control study

Chronic interstitial lung abnormalities have been described in sickle cell disease (SCD) and attributed to repetitive episode of acute chest syndrome. We report a series of 22 cases of diffuse cystic lung disease in SCD with a case–control study to hunt for mechanism. On pathological analysis of a surgical lung biopsy of the index case, the bronchioles had the appearance of constrictive bronchiolitis. Pulmonary function test results revealed lower forced expiratory flow from 25% to 75% of vital capacity in cases versus controls. These findings suggest a bronchiolar mechanism that was not associated with more acute chest syndrome.

Pulmonary function before and after surgical correction of scoliosis

Background As one of the restrictive lung diseases, scoliosis can be treated by surgical intervention to enhance the pulmonary function of that group of patients. The purpose of the study was to determine the effects of scoliosis correction on pulmonary function after a 6-month duration. Around 30 patients with scoliosis were aged between 10 and 40 years old subjecting to posterior spinal fusion surgery who had been enrolled in the study; all of them were subjected to Cobb’s angle measuring and pulmonary function test before and 6 months after the operation. Results Cobb’s angle before the operation was 57.3 ± 13.6°, which significantly corrected and reached up to 21.2 ± 7.2° postoperatively with a mean difference of about 36.13°, P < 0.001. The correlation of Cobb’s angle, forced vital capacity (FVC%), and vital capacity (VC%) was significantly negative. Pulmonary function showed restrictive pattern; forced vital capacity “FVC”, forced expiratory volume 1 “FEV1”, vital capacity “VC”, and forced expiratory flow “FEF 25–75%” were 62.4± 18.06, 65.6±20, 60.7±17.8, and 79.6±28.5, respectively; after 6 months, the reading changed to 60.9± 17.9, 64.04±19.3, 59.16±17.5, and 80.26±28.02 respectively with an insignificant difference, P>0.05. Conclusion The pulmonary function showed insignificant changes after 6 months of operation, despite significant changes in Cobb’s angle while the preoperative FVC and VC were inversely correlated with it.