Variation In Peak Expiratory Flow Rate Research Articles

Восстановительная терапия больных бронхиальной астмой: в фокусе дыхательная гимнастика с экспираторным сопротивлением

Aim: to evaluate the effectiveness of high-resistance breathing exercises using flutter as a method of rehabilitation therapy for asthma. Patients and Methods: the patients with asthma were divided into two groups. Group 1 (n=40) received breathing exercises as part of their treatment, which consisted of quiet inhalation through the nose and exhalation into the flutter for 3–5 minutes daily, for a total of 14 procedures per course, in addition to their baseline therapy. In group 2 (n=40), patients received similar drug therapy without performing breathing exercises. The control group (n=40) consisted of healthy volunteers who performed breathing exercises as in group 1. We analyzed changes in clinical and functional parameters over time after a single application of the rehabilitation technique, as well as at baseline and after completing treatment (after 14 days). Results: showed a significant increase (p<0.05) in external respiration indices, specifically forced expiratory volume in the 1st second, forced vital capacity (FVC), and expiratory reserve volume in groups 1 and 2. Furthermore, group 1 reported a significant increase (p<0.05) in the time to hold breath, as well as an increase in peak expiratory flow, peak expiratory flow rate (PEFR), and a decrease in the daily variation of PEFR and minute ventilation. After two weeks of treatment, group 1 showed significant improvement. The study showed a decrease in choking incidents, reduced need for bronchodilators, and improvement in symptoms such as cough, dyspnea, expectoration of sputum, its character, and wheezing. Additionally, there was an improvement in disease control and exercise tolerance as demonstrated by the results of the 6-minute walk test. Group 2 showed a stable disease course during the follow-up, but no significant changes in clinical manifestations or pharmacological therapy were reported. In this study, it was found that flutter therapy had a significant and moderate favorable effect on 80% and 20% of patients with asthma, respectively. However, this effect was only maintained in patients who regularly practiced high-resistance breathing exercises. No adverse events were reported. Conclusion: high-resistance breathing exercises can reduce hyperventilation and improve bronchial patency in patients with asthma. Additionally, flutter therapy can decrease the doses of bronchodilators, improve FVC, and positively impact the disease course. KEYWORDS: asthma, breathing exercises, expiratory resistance, flutter therapy. FOR CITATION: Alekseenko S.N., Churyukina E.V., Ukhanova O.P., Kas'yanova T.R., Kotieva I.M., Kokova L.N., Dodokhova M.A., AndreevaV.O., Puzikova O.Z., Popova V.A., Sozaeva D.I. Rehabilitation therapy in asthma: focus on high-resistance breathing exercises. Russian Medical Inquiry. 2024;8(3):143–149 (in Russ.). DOI: 10.32364/2587-6821-2024-8-3-4.

Diurnal variation of peak expiratory flow rate in adolescents

Lung functions exhibit a circadian rhythm. Peak Expiratory Flow Rate (PEFR) is an easily measured and reproducible parameter for measuring lung functions. Limited information is available on the circadian variations in lung functions in south Indian adolescents. Hence, this study was undertakento evaluate the diurnal variation of PEFR in adolescents.This longitudinal study was conducted among 30 adolescent girls in the age group of 18-19 years recruited from a hostel in Chirala, Andhra Pradesh. Smokers, pregnant women and subjects with history of tuberculosis were excluded from the study. PEFR was measured using the Mini — Wright s, peak flow meter, four times a day (5.30 – 6.00 am, 12.00-1.00 pm, 5.00-6.00 pm, 9-10.00pm) and the diurnal variation of lung function was calculated. The PEFR values at different time points were analyzed using analysis of variance. Statistical significance was taken at 5% level of significance. Amplitude % Mean and Standard deviation % Mean were used to estimate diurnal variation of PEFR. The mean PEFR recorded at 5.30 am, 12.00 noon, 5.00 pm and 9.00 pm were 340, 347, 349 and 348 respectively. The mean of amplitude % mean and standard deviation % mean obtained in this study were 8.42 ± 3.65and 3.87±1 respectively.C The results of this study indicate that PEFR in adolescents exhibits a definite circadian rhythm, it being lowest early in the morning, progressively rises till late afternoon following which there is a slight fall in the night.

ASTHMA EXACERBATION DUE TO ORAL CONTRACEPTIVE PILLS

ASTHMA EXACERBATION DUE TO ORAL CONTRACEPTIVE PILLS

Regression Equations for Spirometry in Children Aged 6 to 17 Years in Delhi Region

Most of the studies carried out in India to develop regression equations for spirometry in children are now several years-to-decades old and had used equipment and measurement protocols that have since changed. Prediction equations using the current standardisation protocols for spirometry are not available. The lung health of the population may have changed too. To develop regression equations for spirometry for children aged 6 to 17 years of north Indian origin in Delhi region. School children of north Indian origin, as determined by mother tongue and parentage, aged 6 to 17 years were screened by a health questionnaire and physical examination and those found "normal" underwent spirometry according to the standardised procedure recommended by the American Thoracic Society/European Respiratory Society (ATS/ERS) task force in 2005. Pearson's correlation analysis was carried out to identify the predictor variables for spirometric parameters. Prediction equations were developed using the multiple linear regression procedure. The independent variables were entered in sequence of height, age and weight. R2, adjusted R2 and R2 change, standard errors of the estimate (SEE), and estimates of regression coefficients were obtained and the goodness of fit was examined. Data was obtained in 365 boys and 305 girls. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1) peak expiratory flow rate (PEFR), forced expiratory flow rate at 50% and 75% exhalation of vial capacity (F50 and F75) and mean forced expiratory flow rate over the middle 50% of the vital capacity (F25-75) showed moderate to strong correlations with age, height and weight in both boys and girls. In both genders, the equations explained very high variability of FVC, FEV1 and PEFR as shown by the R2 values. The explained variability for flow rates was lesser, with that for F75 being the least. Regression equations for spirometry variables for children of north Indian origin in Delhi region have been developed. These represent the first such effort from India after the publication of the ATS/ERS task force 2005 guidelines on standardisation of spirometry.

Once-Daily vs. Twice-Daily Administration of Inhaled Budesonide for Mild and Moderate Well-Controlled Childhood Asthma: A Randomized, Controlled Trial.

To compare median change in morning peak expiratory flow rate (PEFR) and clinical asthma control in children receiving total daily dosage of inhaled budesonide administered either as once-daily or divided twice-daily dose. It was a randomized, parallel group, open label, noninferiority trial on 80 children aged 5-12 y with mild or moderate well-controlled asthma. Baseline parameters were recorded and subjects received inhaled budesonide either as once-daily or divided twice-daily dose. Primary outcome was median change in morning PEFR. Secondary outcomes included median change in evening and diurnal variation in PEFR, asthma symptom control as per Global Initiative for Asthma, 2017 and Asthma Control Questionnaire, and spirometric measurements taken at the clinic. The median [interquartile range (IQR)] increase in morning PEFR was more in children receiving once-daily as compared to those receiving twice-daily inhaled budesonide (by 6:00L/min; IQR: -44.00-63.00L/min vs. 4:00L/min; IQR: -67.50-67.50L/min, p 0.222; 95% CI: -1.37 to 19.08). Other spirometric variables and symptoms scores were also nonsignificant except median change in evening PEFR which was in favor of twice-daily regimen. Once-daily administration of inhaled budesonide is noninferior to twice-daily administration of equivalent daily dosage of inhaled budesonide.

Prediction Model for Peak Expiratory Flow Rate in Rural Indian Girls

Peak Expiratory flow rate (PEFR) is an easy method to evaluate the airway & lung function. The need for normative data for PEFR is expressed by many researchers. The American thoracic society (ATS) & European Respiratory Society (ERS) has recommended to establishing local reference values for PEFR & other lung function parameters. The research to establish reference data for PEFR in India is a relatively ignored aspect. The reference data is available for adult population. In a paediatric population, the data is available for South Indian, North Indian urban boys. The rural population is not studied well. The current study was designed to understand the relation of PEFR with age, height, weight, body mass index (BMI), body surface area (BSA) & to establish a reference prediction equation in rural girls living in Maharashtra. PEFR was taken in 6-15 years aged 262 school going normal healthy rural girls from Bansarola village, District Beed, Maharashtra. The height, weight, age, BMI & BSA was measured. The correlation was done by Pearson’s correlation coefficient & regression analysis was done for predicting the statistical models. Correlation was significant at the 0.01 level (2-tailed). Diagnostic F value of model was 75.892. PEFR was correlated with age, height, weight, BMI & BSA. The weight & BSA explained maximum variation in data whereas BMI explained the least variation. PEFR values in rural girls were lower than urban boys & girls.In conclusion there are variation in PEFR amongst urban & rural girls which highlights the need to establish local data & prediction equations for PEFR.

Immediate Effects of Sensorimotor Training in Airway Protection (smTAP) on Cough Outcomes in Progressive Supranuclear Palsy: A Feasibility Study.

Progressive supranuclear palsy (PSP) is a neurodegenerative disease characterized by a high prevalence of dysphagia, cough dysfunction, and resultant aspiration pneumonia. Sensorimotor cough function is important for airway clearance in people with dysphagia. Upregulation of cough has been demonstrated in healthy adults and Parkinson's disease; however, the feasibility of cough rehabilitation in PSP is unknown. We sought to assess feasibility by examining the immediate effects of a novel sensorimotor training in airway protection (smTAP) on upregulation of cough function in PSP. Fifteen individuals with PSP enrolled in this study. Baseline voluntary and reflex cough testing were completed. During smTAP, participants were presented with subthreshold capsaicin and instructed to cough with sufficient intensity to hit a target line (set 25% above baseline reflex peak cough flow) via cough airflow visual biofeedback. Twenty-five repetitions were targeted within a single session. Wilcoxon signed-rank tests compared cough airflow measures between baseline voluntary cough testing, the initial five trials of smTAP, and final five trials. Mean peak expiratory flow rate (PEFR) significantly increased from initial to final smTAP trials (p < 0.001). Fourteen participants increased PEFR, with gains of more than 10% in 11 participants. Variability of PEFR (p = 0.01) and cough expired volume (p = 0.01) significantly decreased across smTAP trials. This study is the first to demonstrate the ability of people with PSP to immediately upregulate cough function, providing preliminary support for the feasibility of cough rehabilitation in this population with this novel treatment approach. Future research examining the effects of multiple sessions of smTAP on cough outcomes is warranted.

Factors Affecting Peak Expiratory Flow Rates in Children of 9–12 Years of Age

Introduction: Documentation of peak expiratory flow rate (PEFR) variability may be used to support the diagnosis of asthma and other respiratory disorders. Methodology: This study was carried to measure PEFR of 510 children age group 9 to 12 years of both sexes using a Mini WrightTM Peak Flow Meter. Results were analyzed to find out the normal values of peak expiratory flow rate at each age and either sex. The results were also analyzed to find out what factors influence the peak expiratory flow rate. Effect of age, sex, height, weight, chest circumference, socioeconomic status, passive smoking, cooking fuel, history of contact with tuberculosis and bronchial asthma in family were analyzed separately. Results: The average peak expiratory flow rate in boys was 272±53.16 L/min and for girls was 252±45.09 L/min. For the given age boys have higher peak expiratory flow rate than girls. The peak expiratory flow rate shows very good correlation with height and weight in both sexes. A History of contact with tuberculosis is associated with lower peak expiratory flow rate. Children coming from homes with firewood being used as a fuel and passive smoking had lower peak expiratory flow-rate. No significant relation has been found between peak expiratory flow rate and socioeconomic status and family history of bronchial asthma. Conclusions:The peak expiratory flow rate values of children in study region were comparatively low to those of North Indian and Western children but more compared to urban south Indian children.

Fractional exhaled nitric oxide is a useful adjunctive modality for monitoring bronchial asthma.

Background and Objective:To evaluate the utility of fractional exhaled nitric oxide (FeNO) in monitoring asthma control.Materials and Methods:Steroid naïve nonsmoking asthmatics were recruited and followed for 6–8 weeks on standard treatment. Serial measurements of FeNO, peak expiratory flow rate (PEFR) variability, forced expiratory volume in 1 s (FEV1), bronchodilator reversibility (BDR), and asthma control test (ACT) score were measured at baseline and after 6–8 weeks of treatment.Results:One hundred and fifty-one patients were recruited over an 18-month period. These comprised 79 males (52.3%) with mean (standard deviation) age of 34.2 (11.6). Mean (SD) FeNO levels at baseline and after therapy were 45.4 (35.9) and 38.4 (23.7) ppb, respectively (P = 0.01). Baseline FeNO correlated strongly with FEV1 (r = −0.78, P < 0.001), ACT score (r = −0.76, P < 0.001), PEFR variability (r = −0.74, P < 0.001), and moderately with BDR (r = 0.50, P < 0.001). After treatment with inhaled steroids, the correlation remained strong with ACT score (r = −0.68, P < 0.001) but weakened with PEFR variability (r = −0.34, P = 0.01) and FEV1 (r = −0.36, P = 0.01).Conclusions:FeNO may be useful as an adjunctive noninvasive modality to assess asthma control in both steroid naïve asthmatics and asthmatics on treatment. However, the suboptimal sensitivity and specificity may limit its utility as a point-of-care single monitoring tool.

Diurnal variation of peak expiratory flow rate in healthy young adults: A gender-based study

Background: Peak expiratory flow rate (PEFR) variability follows a diurnal rhythmic pattern in healthy people as well as in asthmatics. A number of studies are there on diurnal variation of PEFR in asthmatics. However, there are fewer studies on diurnal variation in PEFR in young adult male and female in Indian population. Objective: To find out diurnal PEFR variability in young male and female separately in Indian population. Materials and Methods: Sixty-three male and 40 female medical students of age 18–24 years were recruited for this study as the participants. After proper training, PEFR recording of the participants was taken at 6–7 am, 9–10 am, 1–2 pm, 5–6 pm, and 10–11 pm by Mini-Wright peak flow meter. Recording was done by students themselves in guidance of principal investigator. Data analysis was done by unpaired t-test and one-way ANOVA. Diurnal variation of each participant was calculated by two indices, i.e., amplitude percent mean (A%M) and standard deviation percent mean (SD%M). Results: There was a significant difference in PEFR at different time periods in both male and female (P = 0.000) which shows lowest at morning followed by progressive rise in day, highest at evening, and again fall at bedtime. A%M between male and female was found significant (P = 0.019), but SD%M between male and female was not significant (P = 0.105). Conclusion: Our study provides the reference data of diurnal variation of PEFR in male and female which further will be helpful in diagnosis and monitoring of bronchial asthma patients.

Relation of peak expiratory flow rate to body mass index in young adults

Background: Peak expiratory flow rate (PEFR) is a measure of airflow in bronchial tree and it provides idea of bronchial tone. It is affected by age, sex, height, body weight, and other physical activity. There is evidence that obesity has a link to bronchial hyperresponsiveness. Thus, we proposed this study to find out the relation between PEFR and body mass index (BMI). Materials and Methods: In this study, 56 male and 49 female young subjects (total = 105) were recruited. As sex is a definite factor for variation in PEFR, subjects were classified into normal (BMI = 18–24.99 kg/m2), over weight (BMI = 25–29.99 kg/m2), and obese (BMI = 30–34.99 kg/m2) separately for both male and female. After written consent, PEFR of each subject was recorded between 7 and 8 am. Then, data analysis was done by one-way ANOVA, Pearson correlation, and regression analysis. Results: In male subjects, the mean difference of PEFR of normal, over weight, and obese subjects were 498 L/min, 488 L/min, and 391 L/min, respectively, which is statistically significant (P = 0.000). In female subjects, the mean difference of PEFR of normal, over weight, and obese subjects were 377 L/min, 348 L/min, and 325 L/min, respectively, which is statistically significant (P = 0.002). Pearson correlation showed negative correlation between BMI and PEFR both in male (r = −0.512) and in female (r = −0.539). Conclusion: This study concluded that PEFR declines with increase in BMI, and there is negative correlation between BMI and PEFR.

Low-dose sublingual immunotherapy compared to subcutaneous immunotherapy and conventional therapy in childhood asthma

Background Evidence begin to accumulate that high-dose sub-lingual immunotherapy (SLIT) is as effective as subcutaneousimmunotherapy (SIT) in the treatment of childhood asthma.Since the capacity of sublingual area is similar whether the doseis high or low, the efficacy of low dose may be important to bestudied.Objective To investigate the efficacy of low-dose sublingual im-munotherapy in the treatment of childhood asthma.Methods Parents signed informed consent prior to enrollment,after having received information about the study. Patients weremoderate asthma aged 6-14 years with disease onset of lessthan 2 years before the commencement of the study and peakexpiratory flow rate (PEFR) variability of more than 15%. Pa-tients were randomly allocated into group A, B, and C whoreceived subcutaneous immunotherapy, low-dose sublingualimmunotherapy, and conventional asthma therapy, respectively.Randomization was stratified into two strata according to agei.e., 6-11 years or 11-14 years. Patients of each stratum wererandomized in block of three for each group. At the end of threemonths, lung function tests were repeated. The primary outcomewas PEFR variability at the end of the study. The study wasapproved by the Ethics Committee of Soetomo HospitalSurabaya.Results Distribution of variants as represented by sex, age,eosinophil count, and total IgE concentration were normal inthe three groups. PEFR variability decreased significantly from16.97+0.81 to 8.50+5.08 and 17.0+0.87 to 8.40+4.72 in groupreceiving SIT and SLIT, respectively (p&lt;0.05), but decreasednot significantly from 17.00+0.83 to 10.82+0.5.41 in control group(p&gt;0.05).Conclusion Low-dose SLIT is as efficacious as SIT in the treat-ment of moderate asthma in children

Evaluation of diurnal variation in peak expiratory flow rates in healthy Indian adult male and female subjects

Background: Peak expiratory flow rate (PEFR) reflects the strength and condition of respiratory muscles and the degree of airflow limitation in large airways. PEFR shows hour-to-hour variation that follows a specific pattern, which has been identified in both asthmatics and healthy individuals. Adequate data were not available for the diurnal variation in normal individuals who are students in professional courses and lead a sedentary lifestyle. Hence, this study was undertaken to study the diurnal variation in PEFRs in healthy adult male and female subjects in South India. Materials and Methods: PEFR was recorded in 50 healthy adult male and 50 healthy adult female students aged 18-23 years who were enrolled in professional courses [e.g. Bachelor of Medicine (MBBS), Bachelor of Dental Surgery (BDS), Nursing, and Master of Science (M.Sc.)]. Mini-Wright peak flow meter was used to measure the PEFR. The PEFRs were recorded at 7-8 AM, 10-11 AM, 1-2 PM, 4-5 PM, and 7-8 PM for 2 consecutive days. Results: On analysis of the PEFR records of individual subjects, it was seen that there was an overall dip in the morning at 7-8 AM PEFR, which increased in the daytime, peaking in the afternoon at 4-5 PM and eventually decreased in the night. The subjects did not show the peak PEFR values at the same time point, 16% of the subjects had a rise in PEFR in the early morning, afternoon (1-2 PM) peak was observed in 22% of subjects, and evening (4-5 PM) peak was observed in 36% of subjects. Only 2% of subjects showed a peak in the night time (7-8 PM) PEFR values. Conclusion: This study provided the preliminary reference data of diurnal variation of PEFR in healthy adults. There is a variation in the PEFR recorded during different time points of the day; hence, in order to compare the PEFR between individuals it is advisable to record the PEFR at the same time point. The difference in diurnal variation may be due to the difference in the waking up time between the male and the female subjects as the peak PEFR is generally seen at the midtime of the entire duration when the subject is awake.

An Indian study of postural variation in peak expiratory flow rates in healthy, adult, male participants

Background Peak expiratory flow rate (PEFR) reflects the strength and condition of respiratory muscles and the degree of airflow limitation in large airways. PEFR showing postural variation that follows a specific pattern in asthmatics and healthy individuals has been identified. Adequate data are not available for postural variation in normal individuals who are students of professional courses with a sedentary lifestyle. Lung volumes in normal individuals were significantly higher in the standing position. Some studies have reported that in healthy participants spirometric indices were higher while standing in comparison with the sitting position, whereas other studies have reported no differences between spirometric values obtained in the lying, sitting and standing positions. Hence, this study was undertaken to study the postural variation in PEFRs in healthy, adult, male participants in south India. Materials and methods PEFR was recorded in 50 adult, healthy, male participants aged 18–23 years who were students of professional courses. Mini Wright’s peak flow meter was used to measure the PEFR. Three readings were taken in the standing and lying positions. The best of the three recordings was considered as the final value. Results PEFR was decreased while lying down compared with standing in the participants studied, and the quantum of difference was noted. Conclusion With postural changes, the PEFR significantly differs on the basis of whether the measurements are taken in the standing or in the lying posture in healthy participants. The effect of posture may be of importance in recording PEFR, and changing to a better posture may be especially useful for those with weak expiration.

A study of postural variation in peak expiratory flow rates in healthy adult female subjects in South India

Background: Peak expiratory flow rate (PEFR) reflects the strength and condition of respiratory muscles and the degree of airflow limitation in large airways. PEFR shows postural variation that follows a specific pattern in asthmatics and healthy individuals has been identified. Adequate data are not available for the postural variation in normal individuals, who are students in professional courses, and had a sedentary lifestyle. Lung volumes in normal subjects were significantly higher in a standing position. Others have reported that in healthy subjects spirometric indices were higher in the standing in comparison with the sitting position whereas other studies have reported no differences between spirometric values obtained in lying, sitting, and standing positions. Hence, this study is undertaken to study the postural variation in PEFR in healthy adult female subjects in South India. Methods: PEFR was recorded in 50 adult healthy female students aged 18-23 years and studying in professional courses (MBBS, BDS, Nursing, and MSc). Mini wright's peak flow meter was used to measure the PEFR. Three readings were taken PEFR in standing and lying posture. Best of three recordings is taken as the final value. Results: PEFR is decreased in lying posture compared to standing posture in subjects studied, and the quantum of difference was noted. Conclusion: In postural changes, PEFR measurements significantly differ based on whether the measurements are taken in the standing or in the lying posture in healthy participants. The effect of posture may be of importance in recording PEFR and changing to a better posture may be especially useful for those patients with weak expiration.

Study of diurnal variation in peak expiratory flow rates in healthy men in South India

Background Peak expiratory flow rate (PEFR) reflects the strength and condition of respiratory muscles and the degree of airflow limitation in large airways. PEFR shows hour-to-hour variation that follows a specific pattern in asthmatics and in healthy individuals. Adequate data are not available on the diurnal variation in normal individuals who are students in professional courses and living a sedentary lifestyle. Hence, this study was undertaken to study the diurnal variation in PEFRs in healthy men in South India. Participants and methods PEFR was recorded in 50 adult healthy male students who were nonsmokers, between 18 and 23 years of age and studying in professional courses (MBBS, BDS, Nursing and MSc). Mini Wright's peak flow meter was used to measure the PEFR. PEFRs were recorded at 7-8 a.m., 10-11 a.m., 1-2 p.m., 4-5 p.m. and 7-8 p.m. for 2 consecutive days. Results On analysis of PEFR records of each individual, it was seen that there was an overall dip in the morning at 7-8 h PEFR, which increased during the daytime, peaking in the afternoon at 4-5 p.m. and eventually decreased in the night. Participants did not show the peak PEFR values at the same time point: 16% of participants had a rise in PEFR in the early morning hours; afternoon (1-2 p.m.) peak was observed in 22% of participants; and evening (4-5 p.m.) peak was observed in 36% of participants. Only 2% of participants showed a peak in the night time (7-8 p.m.) PEFR values. Conclusion This study provided the preliminary reference data of diurnal variation of PEFR in healthy adults. As there is a variation in the PEFR recorded during different time points of the day, it is advisable to record the PEFR at the same time point to compare the PEFR between individuals.

Asthma-like peak flow variability in various lung diseases

Background and Objectives:Bronchodilator reversibility and diurnal peak flow variability are considered characteristic of asthma patients. Patients with chronic obstructive pulmonary disease (COPD) show poor reversibility. But reversibility and variability in other pulmonary diseases manifesting with airflow obstruction in not known. Therefore, we assessed reversibility and peak flow variability in patients with various lung diseases to recognize the pattern.Materials and Methods:Seventy consecutive patients with a diagnosis of lung diseases manifesting with airflow obstruction were recruited in the study. These included 23 patients with asthma, 11 patients with bronchiectasis, 16 patients with post-tubercular lung disease (PTLD), and 20 patients with COPD. Ten healthy matched control subjects were also selected to pair with asthmatic patients. Bronchodilator reversibility test was done initially and peak expiratory flow rate (PEFR) was measured for a duration of 1 week by patients themselves on a chart that was given to them. The mean amplitude percentage of these records were analyzed.Results:The mean values of peak flow variability were 14.73% ± 6.1% in asthmatic patients, 11.98% ± 7.5% in patients with bronchiectasis, and 10.54% ± 5.3% in PTLD. The difference in the mean values of peak flow variability between asthma and bronchiectasis, that is, 14.73 (6.1) vs 11.98 (7.5) was not statistically significant (P > 0.05). Forced expiratory volume one second (FEV1) reversibility values were 14.77% ± 26.93%, 11.24% ± 20.43%, 10.85% ± 13.02%, 16.83% ± 22.84%, and 5.47% ± 4.99% in asthma, COPD, PTLD, bronchiectasis, and healthy subjects, respectively.Conclusion:Both reversibility and diurnal peak flow variability were higher in patients with various lung diseases compared with normal healthy subjects. Although these are characteristic of asthma, some cases of bronchiectasis and PTLD patients may also manifest asthma-like PEFR variability and reversibility.

Comparison of Peak Expiratory Flow Rate Variability Between Asthmatics and Healthy Individuals of Chennai City, India

Comparison of Peak Expiratory Flow Rate Variability Between Asthmatics and Healthy Individuals of Chennai City, India

Leukotriene Receptor Antagonists: A Good Choice in the Treatment of Premenstrual Asthma?

The aim of this study was to investigate the effects of leukotriene receptor antagonists (LTRAs) on the premenstrual exacerbation of asthma (PMA). Twenty-four female patients with mild asthma were enrolled in the study. Patients were followed for three menstrual cycles and separated into two groups based on whether they exibit premenstrual worsening of asthma symptoms (n = 11) or not (n = 13). During the first month all were treated with only inhaled steroids (IS) (run-in period); during the second month they received IS plus placebo; and during the third month they were given IS plus montelukast. Furthermore, they were advised to use beta 2 -agonists as needed. Peak expiratory flow rate (PEFR) and symptom scores were recorded during the 3 months. Pulmonary function tests (PFT) and the levels of oestrogen, progesterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured a week before the begining of the menstrual period. At the end of the 3-month period, it was observed that following therapy with montelukast, the patients with PMA showed significant improvement in PEFR variability and symptom scores when compared with the placebo group. Baseline FSH levels were higher, but FSH and other hormone levels and PFTs did not change in these groups. However, in the group without PMA there was no difference between the montelukast or placebo groups in PEFR variability, symptom scores, PFTs, and hormone levels. Based on the data in hand, it could be stated that LTRAs have ensured the control of symptoms and improved PEFR variability in patients with PMA by supressing inflammation. We are of the view that LTRAs would be a right choice in the treatment of patients with PMA.

Circadian changes in granulocyte-macrophage colony-stimulating factor message in circulating eosinophils

Granulocyte-macrophage colony-stimulating factor (GM-CSF), which stimulates eosinophil recruitment, activation, and survival, is expressed by activated eosinophils. Although eosinophil recruitment and enhanced survival have been associated with nocturnal asthma (NA), the contribution of GM-CSF to NA is unknown. To determine whether circulating eosinophil GM-CSF expression correlates with the symptoms of NA. The GM-CSF messenger RNA (mRNA) expression at 4 PM and 4 AM was determined by reverse-transcriptase polymerase chain reaction with Southern blot analysis in subjects with and without NA and in controls. A total of 142 asthma subjects were screened for nocturnal asthma with 1-week home peak expiratory flow rate (PEFR) monitoring. Eleven subjects had NA (>20% diurnal variation in PEFR on 4 of 7 days), and 6 met the criteria for non-NA (<10% diurnal variation in PEFR on 7 of 7 days); 8 controls were studied. In subjects with NA, GM-CSF mRNA expression in circulating eosinophils increased 3-fold at 4 AM compared with 4 PM. Diurnal changes in GM-CSF mRNA expression were not detected in the non-NA and control groups. Day-night variation in eosinophil GM-CSF expression is associated with circadian variation in airway function in asthma, a key manifestation of asthma severity.