Reproducible Spirometry Research Articles

Thinness negatively affects lung function among Sri Lankan children.

BackgroundThere have been conflicting findings on the effect of body mass index (BMI) on lung functions in children. Therefore, we studied the relationship between spirometry parameters and BMI among healthy Sri Lankan school children aged 5–7 years.MethodsA cross-sectional study was conducted among 296 school children (5–7-year-old) without apparent lung disease. Recruitment was done with stratified random sampling. Spirometry parameters, FEV1, FVC, PEFR, and FEV1/FVC ratio were determined. The acceptable and reproducible spirometry recordings were included in the analysis. Simple and multivariate linear regression analysis examined possible associations of lung function parameters with BMI, socio‐demographic variables and indoor risk factors. Also, the mediator effect of gender on lung function through BMI was explored.ResultsThe participants’ mean age (SD) was 6.4 (0.65) years. One-third were thin/severely thin (37%). A statistically significant difference in FVC (p = 0.001) and FEV1 (p = 0.001) was observed between BMI groups (obesity/overweight, normal, and thinness). Yet, PEFR or FEV1/FVC did not significantly differ among BMI groups (p = 0.23 and p = 0.84). Multivariate regression analysis showed that FEV1 and FVC were significantly associated with BMI, child’s age, gender, family income, father’s education, having a pet, and exposure to mosquito coil smoke. Interaction between gender and BMI for lung functions was not significant. The thin children had significantly lower FVC (OR: -0.04, 95%CI: -0.077, -0.012, p = 0.008) and FEV1 (OR: -0.04, 95%CI: -0.075, -0.014, p = 0.004) than normal/overweight/obese children. Family income demonstrated the greatest effect on lung functions; FVC and FEV1 were 0.25L and 0.23L smaller in low-income than the high-income families.ConclusionLower lung function parameters (FVC and FEV1) are associated with thinness than normal/overweight/obese dimensions among children without apparent lung disease. It informs that appropriate nutritional intervention may play a role in improving respiratory health.

P101 Provision of home spirometry in a physiologist-led service: experiences from a large adult cystic fibrosis centre

Objectives: Spirometry is an important marker of lung health in people with cystic fibrosis (pwCF). During the SARS-CoV-2 pandemic, the aerosol-generating nature of spirometry coupled with service user shielding disrupted its routine monitoring. To maintain continuity, we implemented a home spirometry service to complement our telemedicine clinic. Methods: We provided NuvoAir Air Next© home spirometers in clinic or by courier to those of our adult CF cohort with good service engagement and spirometry technique. Training and instruction was given by ARTP-registered physiologists, who are also available at telemedicine clinics to grade spirometry and offer support to service users. Results are uploaded by pwCF via a connected phone. We report our experiences, and the quality of independently-performed home spirometry as graded against ATS/ERS guidelines. Results: Over 4 months, we provided 302 of the 354 pwCF attending our centre with spirometers ([mean ± SD] age 32 ± 11 years (range 17–76), BMI 23.4 ± 4 kgm–2, % predicted FEV1 76.5 ± 23.6. Of the 300, 2 did not tolerate home spirometry, one due to an incompatible phone, and one due to poor compliance. 20 (6.8%) pwCF have yet to use their spirometer. 278 (93%) have performed a total of 5,344 manoeuvres across 1,636 sessions (mean sessions 5.8, mean interval 14.9 days, see Table). We report no adverse events. Quality of spirometry below grade D was often repeated after physiologist feedback. Grade E spirometry was often recorded when only a single acceptable spirometry was performed (20%) or when end-of-test criteria had not been met (46.4%). [Table Presented] Conclusion: Home spirometry can be implemented in a large cohort in a short time frame. Engagement and quality of independently performed spirometry in this group of expert performers was high, but falls below that of hospital quality spirometry. The availability of physiologists to support this service in real-time is an important factor in this and in the reinforcement of reproducible spirometry.

A Novel Case-Finding Instrument for Chronic Obstructive Pulmonary Disease in Low- and Middle-Income Country Settings.

BackgroundLow- and middle-income countries (LMICs) account for >90% of deaths and illness episodes related to COPD; however, this condition is commonly underdiagnosed in these settings. Case-finding instruments for COPD may improve diagnosis and identify individuals that need treatment, but few have been validated in resource-limited settings.MethodsWe conducted a population-based cross-sectional study in Uganda to assess the diagnostic accuracy of a respiratory symptom, exposure and functional questionnaire in combination with peak expiratory flow for COPD diagnosis using post-bronchodilator FEV1/FVC z-score below the 5th percentile as the gold standard. We included locally relevant exposure questions and statistical learning techniques to identify the most important risk factors for COPD. We used 80% of the data to develop the case-finding instrument and validated it in the remaining 20%. We evaluated for calibration and discrimination using standard approaches. The final score, COLA (COPD in LMICs Assessment), included seven questions, age and pre-bronchodilator peak expiratory flow.ResultsWe analyzed data from 1,173 participants (average age 47 years, 46.9% male, 4.5% with COPD) with acceptable and reproducible spirometry. The seven questions yielded a cross-validated area-under-the-curve [AUC] of 0.68 (95% CI 0.61–0.75) with higher scores conferring greater odds of COPD. The inclusion of peak expiratory flow and age improved prediction in a validation sample (AUC=0.83, 95% CI 0.78–0.88) with a positive predictive value of 50% and a negative predictive value of 96%. The final instrument (COLA) included seven questions, age and pre-bronchodilator peak expiratory flow.ConclusionCOLA predicted COPD in urban and rural settings in Uganda has high calibration and discrimination, and could serve as a simple, low-cost screening tool in resource-limited settings.

Two vs four puffs of albuterol: does dose change bronchodilator response?

BackgroundReversible obstruction on spirometry may be used to diagnose asthma. As per 2005 American Thoracic Society (ATS) guidelines, our pulmonary center began using 360 µg (four puffs) of albuterol rather than 180 µg (two puffs) to determine reversibility on spirometry starting in 2009.HypothesisWe hypothesized that fewer patients would respond to two puffs of albuterol than four puffs during spirometric testing.MethodsWe retrospectively reviewed records from new asthmatics seen in Pediatric Pulmonary Clinic from March 2002 to April 2014 who performed reproducible spirometry. Patients were divided into two groups based on whether they had received two or four puffs of albuterol for bronchodilator assessment. A positive bronchodilator response was defined as an increase of ≥12% in forced expiratory volume in one second (FEV1) or ≥25% in forced expiratory flow (FEF25–75%). Data were expressed as percentages and mean ± standard error of the mean values. Chi-squared test and Student’s t-test were utilized.ResultsData were collected for 240 patients; 115 patients received two puffs of albuterol and 125 patients received four puffs. There were no significant differences in baseline characteristics between the two groups. There were no differences following two puffs or four puffs in changes in FEV1 (10.0±1.1% vs 10.5±1.1% predicted) or FEF25–75% (30.2±2.9% vs 33.5±2.9% predicted). Moreover, there was no difference in ATS-defined bronchodilator response between the two groups.ConclusionBased on the mean change in FEV1 and overall bronchodilator responsiveness, two puffs of albuterol were not inferior to four puffs in the determination of bronchodilator responsiveness in our pediatric asthmatic patients.

Underestimation of spirometry if recommended testing guidance is not followed.

Lung function measured at work is used to make important employment decisions. Improving its quality will reduce misclassification and allow more accurate longitudinal interpretation over time. To assess the amount by which lung function (forced expiratory volume in 1 second [FEV1] and forced vital capacity [FVC]) values will be underestimated if recommended spirometry testing guidance is not followed. Lung function was measured in a population of workers. Knowledge of the final reproducible FEV1 and FVC for each worker allowed estimation of the underestimates that would have occurred if less forced manoeuvres than recommended had been performed. A total of 667 workers (661 males, mean age 43 years, range 18-66) participated. Among them, 560 (84%) achieved reproducible results for both FEV1 and FVC; 470 (84%) of these did so after three technically acceptable forced expiratory manoeuvres, a cumulative total of 533 after four, 548 after five, 557 after six, 559 after seven and 560 after eight blows. If only one (or first two) technically acceptable blow(s) had been performed, mean underestimates were calculated for FEV1 of 115.1 ml (35.4 ml) and for FVC of 143.4 ml (42.3 ml). In this study, reproducible spirometry was achievable in most workers. Not adhering to standards underestimates lung function by clinically significant amounts.

Lower lung function associates with cessation of menstruation: UK Biobank data.

Little is known about the effect of cessation of menstruation on lung function. The aims of the study were to examine the association of lung function with natural and surgical cessation of menstruation, and assess whether lower lung function is associated with earlier age at cessation of menstruation.The study was performed in 141 076 women from the UK Biobank, who had provided acceptable and reproducible spirometry measurements and information on menstrual status. The associations of lung function (forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), spirometric restriction (FVC < lower limit of normal (LLN)), airflow obstruction (FEV1/FVC <LLN)) with cessation of menstruation and age at cessation of menstruation were assessed using regression analysis.Women who had natural cessation of menstruation showed a lower FVC (-42 mL; 95% CI -53- -30) and FEV1 (-34 mL; 95% CI -43- -24) and higher risk of spirometric restriction (adjusted odds ratio 1.27; 95% CI 1.18-1.37) than women still menstruating. These associations were stronger in women who had had a hysterectomy and/or oophorectomy. The earlier the natural cessation of menstruation, the lower the lung function. There was no clear association of lung function with age at hysterectomy and/or oophorectomy. Airflow obstruction was not associated with cessation of menstruation.Lower lung function associates with cessation of menstruation, especially if it occurs early in life.

Feasibility of spirometry testing in preschool children.

The primary purpose of this study was to evaluate the feasibility of obtaining acceptable and reproducible spirometry data in preschool aged children (3-5 years) by technicians without prior experience with spirometry. Two technicians were trained to perform spirometry testing (ndd Easy on-PC) and to administer standardized questionnaires. Preschool aged children were enrolled from two Head Start centers and a local primary care clinic. Subjects were trained in proper spirometry technique and tested until at least two acceptable efforts were obtained or the subject no longer produced acceptable efforts. 200 subjects were enrolled: mean age 4.0 years (± 0.7 SD); age distribution: 51 (25.5%) 3 years old, 103 (51.5%) 4 years old, and 46 (23%) 5 years old. Fifty-six percent male and 75% Hispanic. One hundred thirty (65%) subjects produced at least one acceptable effort on their first visit: 23 (45%) for 3 years old, 67 (65%) for 4 years old, and 40 (87%) for 5 years old. The number of acceptable efforts correlated with age (r = 0.29, P < 0.001) but not gender. The mean number of acceptable efforts on the first visit was 2.66 (± 2.54 SD; range 0-10). One hundred twenty subjects (60%) had two acceptable efforts; 102 had FEV0.5 within 10% or 0.1 L and 104 had FVC within 10% or 0.1 L of best effort. The Asthma Health Screening Survey (AHSS) was 78% sensitive when compared to a specialist exam and 86% compared to a self-reported prior diagnosis of asthma. Technicians without prior experience were able to obtain acceptable and reproducible spirometry results from the preschool aged children; the number of acceptable efforts correlated significantly with age.

Physiologic findings in children previously ventilator dependent at home due to bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is the primary respiratory complication of premature birth. Some preterm newborns develop chronic respiratory failure, requiring home ventilator support. While physiologic measures have been described for prematurely born children, little is known about spirometric indices in patients with severe BPD who were previously ventilator dependent at home. We retrospectively reviewed medical charts of patients with severe BPD who were ventilator dependent at home. We excluded patients with other comorbidities that could contribute to the severity of BPD. Spirometry was performed when the patient was able to follow commands. Between 1984 and 2012, within our severe BPD cohort who previously required home ventilator support, 19 patients were able to perform reproducible spirometry meeting ATS/ERS acceptability criteria. Ten (52.6%) were females, 13 (68.4%) were Caucasians. Mean age at liberation from ventilation was 2.4 years (C.I. 2.0, 2.9) and at decannulation was 3.5 years (C.I. 2.9, 4.0); median age at first reproducible spirometry measurement was 6.6 years (IQR: 4.9, 8.3). Spirometry results revealed significant airway obstruction, as demonstrated by Z-scores values of -1.5 (C.I. -2.5, -0.4) for FVC, -2.7 (C.I. -3.3, -1.9) for FEV1 , and -3.6 (C.I. -4.3, -2.9) for FEF25-75 . More so, serial spirometric measurements' slopes revealed that the airway obstruction remained static over time (FEV1 slope: -0.07, P-value: 0.2624; FVC slope: -0.01, P-value: 0.9064; and FEF25-75 : 0.0, P-value: 0.8532). Extreme prematurity associated with severe BPD requiring home ventilator support carries significant risks of morbidity. These patients had substantially diminished respiratory function reflecting airflow abnormalities that remained static over time.

125 Feasibility of carrying out spirometry in 3 and 4 year old children in a standard clinic setting

Objectives: We used to introduce spirometry to 5 year old (yo) children with the aim of having reliable results by the age of 6. In 2009 we attempted this with 4yos. In 2011 a 2.5yo girl was keen to copy her 4yo sibling so was allowed to try spirometry simply to avoid conflict. Since she made a reproducible effort we decided to attempt this in all 3yos. Methods: Spirometry was carried out in clinic by the physiotherapist who knew which blowing techniques the children had learned during airway clearance, such as bubble PEP. A CareFusion MicroLab spirometer was used with the child incentive. Children aged 3 with good comprehension attempted the test. The parents understood the potential unreliability of the test. The children were asked to perform one long blow similar to blowing out birthday candles. The reaction of the incentive cartoon was explained. The flow-volume loop was checked between blows and further explanation given if necessary. The best of 3 attempts was recorded. Results: Some children took a second breath and others did not complete the blow, particularly after the incentive was met. During successive visits this usually improved. Overall 9 of 10 3−4yos produced reproducible results, 5 of whom had useful results at age 3. Several children have had these repeated on multiple clinic visits showing good lung growth with age. Conclusion:We have demonstrated that it is feasible during normal appointments to undertake reproducible spirometry in a significant proportion of children as young as 3. With the new global lung initiative normal ranges extending to younger age groups we will be able to make an earlier start in following individual trends in lung function.

126 What factors determine lung function decline in Polish CF children?

Objectives: We used to introduce spirometry to 5 year old (yo) children with the aim of having reliable results by the age of 6. In 2009 we attempted this with 4yos. In 2011 a 2.5yo girl was keen to copy her 4yo sibling so was allowed to try spirometry simply to avoid conflict. Since she made a reproducible effort we decided to attempt this in all 3yos. Methods: Spirometry was carried out in clinic by the physiotherapist who knew which blowing techniques the children had learned during airway clearance, such as bubble PEP. A CareFusion MicroLab spirometer was used with the child incentive. Children aged 3 with good comprehension attempted the test. The parents understood the potential unreliability of the test. The children were asked to perform one long blow similar to blowing out birthday candles. The reaction of the incentive cartoon was explained. The flow-volume loop was checked between blows and further explanation given if necessary. The best of 3 attempts was recorded. Results: Some children took a second breath and others did not complete the blow, particularly after the incentive was met. During successive visits this usually improved. Overall 9 of 10 3−4yos produced reproducible results, 5 of whom had useful results at age 3. Several children have had these repeated on multiple clinic visits showing good lung growth with age. Conclusion:We have demonstrated that it is feasible during normal appointments to undertake reproducible spirometry in a significant proportion of children as young as 3. With the new global lung initiative normal ranges extending to younger age groups we will be able to make an earlier start in following individual trends in lung function.

Pharmacist-managed chronic obstructive pulmonary disease screening in a community setting

To implement a spirometry-based chronic obstructive pulmonary disease (COPD) screening in a community pharmacy chain, determine whether pharmacists can accurately perform spirometry screenings and interpret results, and determine whether performing screenings improved enrollment in smoking cessation programs. Prospective study. Kroger pharmacies in the Cincinnati-Dayton Kroger Marketing Area and off-site screening events in Cincinnati, OH, from March to December 2010. Consenting individuals older than 35 years who met inclusion and exclusion criteria. Specially trained community pharmacists administered a validated COPD screening questionnaire and performed spirometry. The results were interpreted, given to the patient, and faxed to the primary care physician. Any patient who was currently smoking was offered smoking cessation counseling. Spirometry technical quality and interpretation accuracy, screening questionnaire scores in relationship to spirometry results, number of patients enrolled in smoking cessation programs. Of the 185 patients, 10 were excluded due to inability to perform spirometry. After review, 174 (99%) of the spirometries were judged acceptable and 157 (90%) demonstrated reproducible results. The mean (+/-SD) score on the COPD Population Screener questionnaire was 2.3 ± 1.6 (range 0-8). Airflow limitation (defined as forced expiratory volume in 1 second/forced vital capacity < lower limit of normal) was detected in 16 (9%) of the patients. Although 12 (75%) of these patients were former or current smokers, only 3 (19%) were at increased risk for COPD based on their screening questionnaire scores. Of the nine current smokers who participated in a follow-up interview, two had successfully abstained from smoking for 6 months after the screening and five others had made an attempt to quit. This study demonstrated that pharmacists are able to perform accurate and reproducible spirometry in a community pharmacy setting.

Feasibility of laparoscopic Nissen fundoplication after pediatric lung or heart–lung transplantation: should this be the standard?

Five-year graft survival in the pediatric lung transplant (LTxp) population is less than 50%, with obliterative bronchiolitis (OB) the leading cause of death at 1, 3, and 5 years post-transplant. Bronchiolitis obliterans syndrome (BOS), defined using spirometry values, is the clinical surrogate for the histological diagnosis of obliterative bronchiolitis. Surgical correction of documented gastroesophageal reflux disease (GERD) has been proposed as a means to potentially delay the onset of BOS and prolong allograft survival in adults before or after lung transplantation but only one such study exists in children. We have examined the safety and possible benefits of laparoscopic antireflux surgery in pediatric patients following lung (LTxp) and heart-lung transplantation (HLTxp). An Institutional Review Board (IRB)-approved retrospective chart review was performed to evaluate the outcomes and complications of laparoscopic antireflux surgery in pediatric lung and heart-lung transplant patients. Spirometry data were collected for BOS staging using BOS criteria for children. Twenty-five lung and heart-lung transplants were performed between January 2003 and July 2009. Eleven transplant recipients, including six double-lung and five heart-lung (HLTxp), with a median age of 11.7 years (range 5.1-18.4 years), underwent a total of 12 laparoscopic Nissen fundoplications at a median of 427 days after transplant (range 51-2310 days). GERD was determined based upon clinical impression, pH probe study, gastric emptying study, and/or esophagram in all patients. Three patients already had a gastrostomy tube in place and two had one placed at the time of fundoplication. There were no conversions to open surgery, 30-day readmissions, or 30-day mortalities. Complications included one exploratory laparoscopy for free air 6 days after laparoscopic Nissen fundoplication for a gastric perforation that had spontaneously sealed. Another patient required a revision laparoscopic Nissen 822 days following the initial fundoplication for a paraesophageal hernia and recurrent GERD. The average length of hospital stay was 4.4 ± 1.7 days. Nine of the 12 fundoplications were performed in patients with baseline spirometry values prior to fundoplication and who could also complete spirometry reliably. One of these nine operations was associated with improvement in BOS stage 6 months after fundoplication; seven were associated with no change in BOS stage; and one was associated with a decline in BOS stage. It is feasible to perform laparoscopic Nissen fundoplication in pediatric lung and heart-lung transplant recipients without mortality or significant morbidity for the treatment of GERD. The real effect on pulmonary function cannot be assessed due to our small sample size and lack of reproducible spirometry in our younger patients. Additional studies are needed to elucidate the relationship between antireflux surgery and the potential for improving pulmonary allograft function and survival in children which has been previously observed in adult patients.

Quality of Spirometry in Primary Care for Case Finding of Airway Obstruction in Smokers

Background: Diagnosis of chronic obstructive pulmonary disease (COPD) and its severity determination is based on spirometry. The quality of spirometry is crucial. Objectives: Our aim was to assess the quality of spirometry performed using a spirometer with automated feedback and quality control in a general practice setting in Switzerland and to determine the prevalence of airflow limitation in smokers aged ≧40 years. Method: Current smokers ≧40 years of age were consecutively recruited for spirometry testing by general practitioners. General practitioners received spirometry training and were provided with an EasyOne™ spirometer. Spirometry tests were assigned a quality grade from A to D and F, based on the criteria of the National Lung Health Education Program. Only spirometry tests graded A–C (reproducible measurements) were included in the analysis of airflow limitation. Results: A total of 29,817 spirometries were analyzed. Quality grades A–D and F were assigned to 33.9, 7.1, 19.4, 27.8 and 11.8% of spirometries, respectively. 95% required ≤5 trials to achieve spirometries assigned grade A. The prevalence of mild, moderate, severe and very severe airway obstruction in individuals with spirometries graded A–C was 6, 15, 5 and 1%, respectively. Conclusion: Spirometries in general practice are of acceptable quality with reproducible spirometry in 60% of measurements. Airway obstruction was found in 27% of current smokers aged ≧40 years. Office spirometry provides a simple and quick means of detecting airflow limitation, allowing earlier diagnosis and intervention in many patients with early COPD.

Sex differences in the clinical presentation and management of airflow obstruction

The aim of the present study was to explore differences in the clinical expression, clinical diagnoses and management of airway diseases in a primary-care setting. Patients aged >or=35 yrs who had ever smoked were enrolled when they presented for any reason to one of eight rural primary-care practices. Respiratory symptom questionnaires and spirometry were administered. In total, 1,034 patients had acceptable and reproducible spirometry, of whom 550 (53%) were males and 484 (47%) were females. Males smoked more than females (41.2 versus 29.2 pack-yrs) respectively, and were more likely to have a pre-bronchodilator forced expiratory volume in one second/forced vital capacity <0.70 at 22.4 versus 11.8%, respectively. However, more females than males reported breathlessness (51.0 versus 42.8%, respectively), a prior diagnosis compatible with airflow obstruction and taking respiratory medications (23.4 versus 14.9%, respectively). In conclusion, the current results suggest that females are more likely than males to report breathlessness and be prescribed respiratory medications independent of differences in the severity of airflow obstruction.

Ozone and PM 2.5 Exposure and Acute Pulmonary Health Effects: A Study of Hikers in theGreat Smoky Mountains National Park

To address the lack of research on the pulmonary health effects of ozone and fine particulate matter (≤ 2.5 μm in aerodynamic diameter; PM2.5) on individuals who recreate in the Great Smoky Mountains National Park (USA) and to replicate a study performed at Mt. Washington, New Hampshire (USA), we conducted an observational study of adult (18–82 years of age) day hikers of the Charlies Bunion trail during 71 days of fall 2002 and summer 2003. Volunteer hikers performed pre- and posthike pulmonary function tests (spirometry), and we continuously monitored ambient O3, PM2.5, temperature, and relative humidity at the trailhead. Of the 817 hikers who participated, 354 (43%) met inclusion criteria (nonsmokers and no use of bronchodilators within 48 hr) and gave acceptable and reproducible spirometry. For these 354 hikers, we calculated the posthike percentage change in forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), FVC/FEV1, peak expiratory flow, and mean flow rate between 25 and 75% of the FVC and regressed each separately against pollutant (O3 or PM2.5) concentration, adjusting for age, sex, hours hiked, smoking status (former vs. never), history of asthma or wheeze symptoms, hike load, reaching the summit, and mean daily temperature. O3 and PM2.5 concentrations measured during the study were below the current federal standards, and we found no significant associations of acute changes in pulmonary function with either pollutant. These findings are contrasted with those in the Mt. Washington study to examine the hypothesis that pulmonary health effects are associated with exposure to O3 and PM2.5 in healthy adults engaged in moderate exercise.

Relationship of pulmonary function among women and children to indoor air pollution from biomass use in rural Ecuador

Approximately half the world uses biomass fuel for domestic energy, resulting in widespread exposure to indoor air pollution (IAP) from biomass smoke. IAP has been associated with many respiratory diseases, though it is not clear what relationship exists between biomass use and pulmonary function. Four groups containing 20 households each were selected in Santa Ana, Ecuador based on the relative amount of liquid petroleum gas and biomass fuel that they used for cooking. Pulmonary function tests were conducted on each available member of the households 7 years of age. The pulmonary functions of both children (7-15 years) and women (16 years) were then compared between cooking fuel categories using multivariate linear regression, controlling for the effects of age, gender, height, and exposure to tobacco smoke. Among the 80 households, 77 children and 91 women performed acceptable and reproducible spirometry. In multivariate analysis, children living in homes that use biomass fuel and children exposed to environmental tobacco smoke had lower forced vital capacity and lower forced expiratory volume in 1s (P<0.05). However, no significant difference in pulmonary function was observed among women in different cooking categories. Results of this study demonstrate the harmful effects of IAP from biomass smoke on the lung function of children and emphasize the need for public health efforts to decrease exposure to biomass smoke.

The prevalence of airflow obstruction in rural primary care

Spirometry has been reported to be under-utilized, and airflow obstruction may be under-diagnosed, in primary care practice. The objective of this study was to determine the prevalence and severity of airflow obstruction in rural primary care settings and the degree to which it can be predicted by clinical characteristics. Spirometry was performed in patients 35 years and older who had smoked, presenting for any reason to one of eight rural primary care practices. Obstruction was defined as an FEV(1)/FVC<0.70. A total of 1046 subjects were recruited of whom 1034 had acceptable and reproducible spirometry. Airflow obstruction was detected in 17.4% (180 patients). Of those with obstruction, 77.2% (se 3.1%) had at least one respiratory symptom versus 62.4% (se 1.6%) without obstruction (P=0.0002). Only 44.9% (se 3.7%) of those with airflow obstruction had been previously diagnosed with obstructive lung disease. Of those with an FEV(1)<50% of predicted, 85% (se 5.6%) were breathless on exertion; however, only 63% (se 7.6%) were being treated with respiratory medications. We conclude that airflow obstruction is common in rural primary care practice and cannot be accurately predicted by symptoms. It is undiagnosed half of the time, and often not treated even when symptomatic.

Spirometric Pulmonary Function in Healthy Preschool Children.

The purpose of this study was to evaluate spirometric lung function in normal children ages 3 to 6 yr. Spirometric measurements were obtained at nursery and daycare centers by experienced pediatric pulmonary function technicians. Of 307 children recruited, 259 fulfilled our criteria as normal. Of these, 82.6% (214) were able to perform technically acceptable and reproducible maneuvers during a testing session limited to 15 min. The regression model with log-transformed parameters of pulmonary function and height had the best correlations. After accounting for height in the model, other physical traits and health questionnaire items did not contribute significantly. PEFR, FVC, FEV1, and FEF25-75 all increased with increasing height; correlation coefficients were 0.73, 0.93, 0.92, and 0.67, respectively. The group mean coefficients of variation for replicate measurements of PEFR, FVC, FEV1, and FEF25-75 were 7.8%, 2.5%, 2.7%, and 8.3%, respectively. There was a significant decrease in the ratio FEV1/FVC with increasing height; the mean predicted FEV1/FVC was 0.97 at 90 cm height and 0.89 at 125 cm height. In conclusion, reproducible spirometry can be obtained in the majority of preschool children and has the potential to improve our assessment and management of pulmonary disease.

Reproducibilidad de espirometrías en trabajadores mexicanos y valores de referencia internacionales

To describe spirometric function and adjustment to foreign prediction equations in Mexican workers claiming work related disability. We reviewed 5771 spirometries done at the Mexican National Institute of Respiratory Diseases performed with equipment and methods proposed by the American Thoracic Society. With the spirometries we generated multiple regression equations separated for men and women based on age and height, compared to other in common use reported by Knudson and Hankinson in North America and by Quanjer in europeans. 80% of the tests were reproducible for FVC and FEV1 according to ATS, whereas 10% were reproducible for neither. Mean FVC in men was 12% above values reported by Quanjer, 22% above Knudson, 3% above Hankinson and 6% above Rodriguez-Reynaga, whereas similar values for women were 18%, 10%, 0% and 1%. Excluding obese and those who had less than 2 acceptable maneuvers, the numbers increase by 1-2%. FEV1 was also above predicted. Most workers requesting disability are able to generate a reproducible spirometry. However for the same gender, age and height, workers had a FEV1 and a FVC above normal values reported by Knudson and Quanjer and are more similar to those reported by Hankinson in Mexican-Americans. While a set of appropriate reference values are obtained, regression equations obtained from the studied group will generate less error in the evaluation of disability in mexican workers. The English version of this paper is available at: http://www.insp.mx/salud/index.html.

Spirometric pulmonary function in healthy preschool children.

The purpose of this study was to evaluate spirometric lung function in normal children ages 3 to 6 yr. Spirometric measurements were obtained at nursery and daycare centers by experienced pediatric pulmonary function technicians. Of 307 children recruited, 259 fulfilled our criteria as normal. Of these, 82.6% (214) were able to perform technically acceptable and reproducible maneuvers during a testing session limited to 15 min. The regression model with log-transformed parameters of pulmonary function and height had the best correlations. After accounting for height in the model, other physical traits and health questionnaire items did not contribute significantly. PEFR, FVC, FEV1, and FEF25-75 all increased with increasing height; correlation coefficients were 0.73, 0.93, 0.92, and 0.67, respectively. The group mean coefficients of variation for replicate measurements of PEFR, FVC, FEV1, and FEF25-75 were 7.8%, 2.5%, 2.7%, and 8.3%, respectively. There was a significant decrease in the ratio FEV1/FVC with increasing height; the mean predicted FEV1/FVC was 0.97 at 90 cm height and 0.89 at 125 cm height. In conclusion, reproducible spirometry can be obtained in the majority of preschool children and has the potential to improve our assessment and management of pulmonary disease.