A cluster randomised controlled trial to reduce respiratory effects of cotton dust exposure among textile workers: the MultiTex RCT study.

BACKGROUND: We determined the effectiveness of an intervention to reduce cotton dust-related respiratory symptoms and improve lung function of textile workers. METHODS: We undertook a cluster randomised controlled trial at 38 textile mills in Karachi, Pakistan. The intervention comprised: training in occupational health for workers and managers, formation of workplace committees to promote a health and safety plan that included wet mopping and safe disposal of cotton dust, provision of simple face masks, and further publicity about the risks from cotton dust. Participating mills were randomised following baseline data collection. The impact of the intervention was measured through surveys at 3, 12 and 18 months using questionnaires, spirometry and dust measurements. The primary outcomes were 1) changes in prevalence of a composite respiratory symptom variable, 2) changes in post-bronchodilator percentage predicted forced expiratory volume in 1 s (FEV1) and 3) changes in cotton dust levels. These were assessed using two-level mixed effects linear and logistic regression. RESULTS: Of 2031 participants recruited at baseline, 807 (40%) were available at the third follow-up. At that point, workers in the intervention arm were more likely to report an improvement in respiratory symptoms (OR 1.58, 95% CI 1.06-2.36) and lung function (FEV1 % pred: ß 1.31%, 95% CI 0.04-2.57%). Personal dust levels decreased, more so in intervention mills, although we did not observe this in adjusted models due to the small number of samples. CONCLUSION: We found the intervention to be effective in improving the respiratory health of textile workers and recommend scaling-up of such simple and feasible interventions in low- and middle-income countries.

An assessment of public experiences and expectations with physicians: a cross sectional study from Karachi, Pakistan.

BACKGROUND: Although physicians are highly regarded members of society, patients are not always satisfied with their care, suggesting a mismatch between the public's expectations and reality. Thus, the aim of this study was to determine the public's expectations regarding roles and responsibilities of a physician, to assess patient experiences, and to evaluate factors associated with the two outcomes. METHODS: A cross-sectional study was conducted via face-to-face structured interviews from July 14th to August 2nd, 2023, in Karachi, Pakistan. The study sample comprised 424 consenting adults enrolled by visiting public spaces (malls, parks, hospitals, and residential areas). A modified version of 'Exceptionally Good Doctor Likert scale', and 'Patient Picker-15' (PPE-15) questionnaires was used. The Likert and PPE-15 sections were scored through pre-decided criteria for expectations and experience, respectively, and categorized using a median cut-off into high and low expectations and negative and positive experiences, respectively for simple and multivariable logistic regression. RESULTS: A median score of 30.5/ 34 (IQR = 3.3) was found for expectations and 4/ 14 (IQR = 4) for experiences. Significant factors associated with expectations were older age groups (OR = 4.54 [1.18-17.50]) and higher monthly household incomes (0.40 [0.20-0.79]), while the odds of negative experiences were lower after visits to emergency departments (0.38 [0.18-0.84]) and private health care centers (0.31 [0.13-0.70]). CONCLUSION: These results suggest that the public has high expectations from physicians, however their experiences are not always positive. Initiatives to develop a patient-centric ethos are needed for which we outline recommendations to both the public and physicians, respectively.

Chronic airflow obstruction attributable to poverty in the multinational Burden of Obstructive Lung Disease (BOLD) study.

Poverty is strongly associated with all-cause and chronic obstructive pulmonary disease (COPD) mortality. Less is known about the contribution of poverty to spirometrically defined chronic airflow obstruction (CAO)-a key characteristic of COPD. Using cross-sectional data from an asset-based questionnaire to define poverty in 21 sites of the Burden of Obstructive Lung Disease study, we estimated the risk of CAO attributable to poverty. Up to 6% of the population over 40 years had CAO attributable to poverty. Understanding the relationship between poverty and CAO might suggest ways to improve lung health, especially in low-income and middle-income countries.

The association of spirometric small airways obstruction with respiratory symptoms, cardiometabolic diseases, and quality of life: results from the Burden of Obstructive Lung Disease (BOLD) study.

BACKGROUND: Spirometric small airways obstruction (SAO) is common in the general population. Whether spirometric SAO is associated with respiratory symptoms, cardiometabolic diseases, and quality of life (QoL) is unknown. METHODS: Using data from the Burden of Obstructive Lung Disease study (N = 21,594), we defined spirometric SAO as the mean forced expiratory flow rate between 25 and 75% of the FVC (FEF25-75) less than the lower limit of normal (LLN) or the forced expiratory volume in 3 s to FVC ratio (FEV3/FVC) less than the LLN. We analysed data on respiratory symptoms, cardiometabolic diseases, and QoL collected using standardised questionnaires. We assessed the associations with spirometric SAO using multivariable regression models, and pooled site estimates using random effects meta-analysis. We conducted identical analyses for isolated spirometric SAO (i.e. with FEV1/FVC ≥ LLN). RESULTS: Almost a fifth of the participants had spirometric SAO (19% for FEF25-75; 17% for FEV3/FVC). Using FEF25-75, spirometric SAO was associated with dyspnoea (OR = 2.16, 95% CI 1.77-2.70), chronic cough (OR = 2.56, 95% CI 2.08-3.15), chronic phlegm (OR = 2.29, 95% CI 1.77-4.05), wheeze (OR = 2.87, 95% CI 2.50-3.40) and cardiovascular disease (OR = 1.30, 95% CI 1.11-1.52), but not hypertension or diabetes. Spirometric SAO was associated with worse physical and mental QoL. These associations were similar for FEV3/FVC. Isolated spirometric SAO (10% for FEF25-75; 6% for FEV3/FVC), was also associated with respiratory symptoms and cardiovascular disease. CONCLUSION: Spirometric SAO is associated with respiratory symptoms, cardiovascular disease, and QoL. Consideration should be given to the measurement of FEF25-75 and FEV3/FVC, in addition to traditional spirometry parameters.

Byssinosis and lung health among cotton textile workers: baseline findings of the MultiTex trial in Karachi, Pakistan.

OBJECTIVES: To assess the association of exposure in cotton mills in Karachi with different definitions of byssinosis and lung health. METHODS: This cross-sectional survey took place between June 2019 and October 2020 among 2031 workers across 38 spinning and weaving mills in Karachi. Data collection involved questionnaire-based interviews, spirometry and measurements of personal exposure to inhalable dust. Byssinosis was defined using both WHO symptoms-based (work-related chest tightness), and Schilling's criteria (symptoms with decreased forced expiratory volume in 1 s (FEV1). Values of FEV1/forced vital capacity ratio below the lower limit of normality on postbronchodilator test were considered as 'chronic airflow obstruction' (CAO). RESULTS: 56% of participants had at least one respiratory symptom, while 43% had shortness of breath (grade 1). Prevalence of byssinosis according to WHO criteria was 3%, it was 4% according to Schilling's criteria, and likewise for CAO. We found low inhalable dust exposures (geometric mean: 610 µg/m3). Cigarette smoking (≥3.5 pack-years), increasing duration of employment in the textile industry and work in the spinning section were important factors found to be associated with several respiratory outcomes. CONCLUSION: We found a high prevalence of respiratory symptoms but a low prevalence of byssinosis. Most respiratory outcomes were associated with duration of employment in textile industry. We have discussed the challenges faced in using current, standard guidelines for identifying byssinosis.

Impact of using different predictive equations on the prevalence of chronic byssinosis in textile workers in Pakistan.

OBJECTIVE: Byssinosis remains a significant problem among textile workers in low/middle-income countries. Here we share our experience of using different prediction equations for assessing 'chronic' byssinosis according to the standard WHO classification using measurements of forced expiratory volume in 1 s (FEV1). METHODS: We enrolled 1910 workers in a randomised controlled trial of an intervention to improve the health of textile workers in Pakistan. We included in analyses the 1724 (90%) men who performed pre-bronchodilator spirometry tests of acceptable quality. We compared four different equations for deriving lung function percentage predicted values among those with symptoms-based byssinosis: the third US National Health and Nutrition Examination Survey (NHANES-III, with 'North Indian and Pakistani' conversion factor); the Global Lung Function Initiative (GLI, 'other or mixed ethnicities'); a recent equation derived from survey of a western Indian population; and one based on an older and smaller survey of Karachi residents. RESULTS: 58 men (3.4%) had symptoms-based byssinosis according to WHO criteria. Of these, the proportions with a reduced FEV1 (<80% predicted) identified using NHANES and GLI; Indian and Pakistani reference equations were 40%, 41%, 14% and 12%, respectively. Much of this variation was eliminated when we substituted FEV1/forced vital capacity (FVC) ratio (

Prevalence and Population-Attributable Risk for Chronic Airflow Obstruction in a Large Multinational Study.

Rationale: The Global Burden of Disease program identified smoking and ambient and household air pollution as the main drivers of death and disability from chronic obstructive pulmonary disease (COPD). Objectives: To estimate the attributable risk of chronic airflow obstruction (CAO), a quantifiable characteristic of COPD, due to several risk factors. Methods: The Burden of Obstructive Lung Disease study is a cross-sectional study of adults, aged ≥40, in a globally distributed sample of 41 urban and rural sites. Based on data from 28,459 participants, we estimated the prevalence of CAO, defined as a postbronchodilator FEV1-to-FVC ratio less than the lower limit of normal, and the relative risks associated with different risk factors. Local relative risks were estimated using a Bayesian hierarchical model borrowing information from across sites. From these relative risks and the prevalence of risk factors, we estimated local population attributable risks. Measurements and Main Results: The mean prevalence of CAO was 11.2% in men and 8.6% in women. The mean population attributable risk for smoking was 5.1% in men and 2.2% in women. The next most influential risk factors were poor education levels, working in a dusty job for ≥10 years, low body mass index, and a history of tuberculosis. The risk of CAO attributable to the different risk factors varied across sites. Conclusions: Although smoking remains the most important risk factor for CAO, in some areas, poor education, low body mass index, and passive smoking are of greater importance. Dusty occupations and tuberculosis are important risk factors at some sites.

Chronic airflow obstruction and ambient particulate air pollution.

Smoking is the most well-established cause of chronic airflow obstruction (CAO) but particulate air pollution and poverty have also been implicated. We regressed sex-specific prevalence of CAO from 41 Burden of Obstructive Lung Disease study sites against smoking prevalence from the same study, the gross national income per capita and the local annual mean level of ambient particulate matter (PM2.5) using negative binomial regression. The prevalence of CAO was not independently associated with PM2.5 but was strongly associated with smoking and was also associated with poverty. Strengthening tobacco control and improved understanding of the link between CAO and poverty should be prioritised.

Recommendations: putting an end to child labour in Pakistan!

Child labour is rampant in Pakistan since ages. Laws, policies, programmes and strategies to eliminate child labour have been in place with little gain. Implementation of laws and sustainability of programmes offer barriers to eliminate the menace. We recommend a new approach of regulating child labour as a strategy to eliminate it in the longer run. Model districts with drop-in-centres offering free education to the working children should be constructed. The key stakeholders should unite on a common platform to formulate guidelines defining the nature and duration of work for children in various sectors such that they have sufficient time to visit the drop-incentres. Once a generation of children is educated, the cycle will start to break itself and gradually we will overcome child labour.

Determinants of occupational hazards knowledge and safety practices among textile workers in Karachi, Pakistan: a cross sectional study.

OBJECTIVE: To determine the factors associated with good knowledge and safe practices regarding occupational hazards among textile workers. METHODS: The cross-sectional study was conducted in Karachi from September 2015 to February 2016, and comprised male workers from seven textile mills. A 45-item structured questionnaire was developed and pretested in Urdu, the local language. One part of the questionnaire comprised 31 items related to good knowledge, and the other part comprised 14 items related to safe practices. Data was analysed using SPSS 19. RESULTS: Of the 300 subjects, 123(41%) were aged 18-27 years, 183(63%) were educated, 184(61.3%) worked more than eight hours daily, 170(57%) were employed in the weaving section and 164(55%) as machine operators. Besides, 231(77%) had good knowledge, and 62(21%) reported safe practices. Educated workers were more likely (p<0.05), and machine operators were less likely (p<0.05) to have good knowledge, while educated workers, those in the spinning section and those working less than 8-hours daily (p<0.05) were more likely to report safe practices. CONCLUSIONS: There was a high knowledge level, but a wide gap in adopting safety practices, which indicates need for focused interventions targeting high-risk workers and regulation of working hours.

Needs assessment regarding occupational health and safety interventions among textile workers: A qualitative case study in Karachi, Pakistan.

OBJECTIVE: To determine the perceived health and safety needs identified by textile workers, managers and experts as well as direct observation of the prevailing health and safety practices in the textile industry. METHODS: The qualitative study using the needs assessment conceptual framework was conducted in July-August 2015 in Karachi, and comprised focus group discussions with textile workers, in-depth interviews with factory managers and health and safety officers, and key informant interviews with relevant stakeholders and experts. A walk-through survey was also conducted in selected mills for which the Checklist of hazards in textiles was used. RESULTS: A total of 6focus group discussions, 6 in-depth interviews and 5 key informant interviews were conducted. Workers were found to have limited knowledge of occupational hazards, preventions and diseases. They identified lack of awareness and non-existent safety mechanisms as areas for improvement. Managers thought preventive practices and health services were not standardised while influence of buyers in the form of international business regulations and legislations were thought to be the enabling factors for enforcing health and safety standards. Poor governance, lack of knowledge regarding labour rights, low literacy level, poor compliance and low wages were the barriers for health promotion at workplace, as identified by the experts. Walk-through survey found mechanisms in place for fire safety, but the workers and managers were generally not using Personal Protective Equipment despite the presence of several hazards at workplace. CONCLUSIONS: There was found a need for context-specific occupational health and safety interventions at individual, organisational and policy levels.

Epidemiology of asthma and associated factors in an urban Pakistani population: adult asthma study-Karachi.

BACKGROUND: This study was conducted in order to determine the prevalence of asthma and associated risk factors in the adult population of Karachi, Pakistan. METHODS: This multi-stage, cross-sectional survey was conducted from May 2014-August 2015; comprising 1629 adults in 75 randomly selected clusters in Karachi, Pakistan. Definitions included: 'self-reported asthma', 'reversibility in FEV1' and 'respiratory symptoms and reversibility in FEV1'. RESULTS: Prevalence of asthma was 1.8% (self-reported) (95% CI: 1.0-2.6), 11.3% (reversibility in FEV1) (95% CI: 9.4-13.3) and 6.6% (symptoms and reversibility in FEV1) (95% CI: 5.1-8.1). Asthmatics were more likely to belong to the age group ≥38 years according to 'reversibility in FEV1' and 'respiratory symptoms and reversibility in FEV1' (AOR: 1.9, 95% CI: 1.2-3.3) and (AOR: 2.1, 95% CI: 1.1-4.2), respectively. Asthmatics were more likely to report history of allergies (AOR: 1.9, 95% CI: 1.2-2.9) and (AOR: 2.8, 95% CI: 1.7-4.8); and were exposed to environmental tobacco smoke (AOR: 1.6, 95% CI: 1.1-2.5) and (AOR: 1.9, 95% CI: 1.1-3.3) according to 'reversibility in FEV1' and 'respiratory symptoms and reversibility in FEV1', respectively. Asthmatics were more likely to report pack years of smoking ≥5 (AOR: 2.3, 95% CI: 1.1-4.7) according to 'respiratory symptoms and reversibility in FEV1'. CONCLUSION: This study reports a high prevalence of asthma among Pakistani adults and calls for developing appropriate public health policies for prevention and control of asthma in the country. Further studies should be conducted to determine the national prevalence as well as follow-up studies to identify preventable causes for adult asthma.

Application of the GPS technology to assess time-location pattern of undergraduate students at a private medical university in Karachi, Pakistan: A pilot study.

To compare time-location pattern of undergraduate university students through GPS and diary method, and with level of physical activity, a cross-sectional survey was conducted from September 2012 - May 2013 involving 50 undergraduate students from Aga Khan University. Data were recorded through GPS, diary method, International Physical Activity Questionnaire (IPAQ-L) and accelerometer (ActiGraph). Median self-reported time spent in the indoor-inside the campus, indoor-outside the campus and outdoor environment was 405 (IQR:300-540), 720 (IQR:465-840) and 300 minutes (IQR:180-495) respectively, while 52% of the students were in moderate, 40% vigorous and 8% in mild categories of physical activity. Mean differences in location (GPS versus diary method) were statistically insignificant; indoor residential, -30.2, indoor other, -26.2, outdoor at rest, 45.9 and outdoor travelling, 10.5 minutes. We conclude that students spent most of their time indoors-outside of campus and majority were physically active, while also demonstrating the applicability of GPS and ActiGraph for such studies.

Validation of respiratory questionnaire for lung function assessment among an occupational group of textile workers in Pakistan.

OBJECTIVE: To determine the association of spirometric lung pattern with respiratory symptoms and to validate the American Thoracic Society respiratory questionnaire for lung function assessment among textile workers. METHODS: This cross-sectional survey was conducted from August to December 2009 among adult textile workers of Karachi. Data was collected through the American Thoracic Society Division of Lung Disease respiratory questionnaire and the lung function was assessed by using a spirometer. Results of three acceptable readings of spirogram were recorded and the best of the three readings was used for analysis. SPSS 19 was used for data analysis. RESULTS: There were 372 participants in the study with an overall mean age of 27±8.5 years. In linear regression analysis, forced expiratory volume in one second for workers who had chronic cough was -829.1 (confidence interval: -1273.1, -385.2), chronic wheeze -168.8 (confidence interval: -319.3, -18.2) and shortness of breath grade 2 -215.6 (confidence interval: -387.8, -43.4). In logistic regression model, after adjusting for covariates, odds of reduced percentage predicted forced expiratory volume in one second for workers who had chronic cough was 3.09 (confidence interval: 1.26, 7.56), chronic wheeze 1.98 (confidence interval: 1.05, 3.71) and shortness of breath grade 2 2.07 (confidence interval: 1.05, 4.07), while odds of reduced percentage predicted forced vital capacity for shortness of breath grade 2 was 2.35 (confidence interval: 1.05, 5.21). In logistic regression model 2, for assessing the effect of different combinations of chronic respiratory symptoms, the odds of reduced percentage predicted forced expiratory volume in one second for the combination of cough and wheeze was 2.08 (confidence interval: 1.05, 4.10), cough and shortness of breath grade 2 2.47 (confidence interval: 1.18, 5.18), phlegm and shortness of breath grade 2 2.59 (confidence interval: 1.23, 5.43), cough, wheeze and shortness of breath grade 2 4.64 (confidence interval: 1.97, 10.93)and cough, phlegm, wheeze and shortness of breath grade 2 4.18 (confidence interval: 1.68, 10.37). CONCLUSIONS: A combination of chronic respiratory symptoms was best associated with decrements in lung function.

Low prevalence of asthma among textile workers in Karachi, Pakistan.

OBJECTIVE: To determine the prevalence of asthma in textile workers through post-bronchodilator spirometry and to compare the differences in prevalence based on different criteria used to assess asthma. METHODS: The cross-sectional study was conducted between July and December 2013 in Karachi, Pakistan, and comprised workers from15 textile mills in the city and its outskirts. Asthma and associated respiratory symptoms were assessed using the American Thoracic Society Division of Lung Diseases Questionnaire, and post-bronchodilator spirometry. SPSS 19 was used for statistical analysis. RESULTS: Among the 372 workers in the study, asthma was found in 19(5%) as diagnosed on post-bronchodilator spirometry. The prevalence of self-reported and physician-diagnosed asthma was 15(4%) and 8(2%) respectively. Work in the spinning section, age ≥38 years, duration of work ≥10 years in textile industry, history of smoking, and ≥10 pack years of smoking were found to be important predictors of asthma. CONCLUSIONS: Textile industry workers had low prevalence of asthma, assessed through post-bronchodilator spirometry, compared to estimates for the general population. This could possibly be due to some protective effect of endotoxin exposure although further evaluation with better exposure assessment is warranted.

Knowledge, attitude and practices regarding respiratory symptoms among textile workers of Karachi, Pakistan: a cross-sectional survey.

OBJECTIVES: To determine the prevalence and predictors of good knowledge, appropriate attitude and appropriate protective practices regarding respiratory symptoms among textile workers, and to determine the association of knowledge, attitude and practices with respiratory symptoms. METHODS: The cross-sectional study was conducted in 2009 and comprised male workers from 15 textile mills in and around Karachi. A structured and pre-tested questionnaire was used which included questions to explore the knowledge, attitude and practices regarding respiratory symptoms. SPSS 19 was used for statistical analysis. RESULTS: The study had a sample size of 372 and found prevalence of good knowledge to be in 182 (48.9%) workers and appropriate attitude in 302 (81%), while only 80 (21%) were practising these measures appropriately. Being educated and older than 38 years of age, belonging to Sindhi ethnicity, and working in the weaving section were significant (p<0.05) predictors of knowledge, attitude and practices. Generally, there was no significant association of knowledge, attitude and practices with respiratory symptoms (p>0.05). CONCLUSIONS: There was low prevalence of appropriate practices, high prevalence of good knowledge and attitude, indicating an interplay of several other social and environmental factors which need to be explored.

COMPARING LUNG FUNCTION OF TEXTILE WORKERS WITH THE HEALTHY PAKISTANI POPULATION.

BACKGROUND: The purpose of this study was to compare lung function of textile workers with healthy Pakistani population, compare predicted values based on the European Respiratory Society (ERS) equations with those based on the Pakistani equations, and to develop predictor equations for textile workers in Pakistan. METHODS: This was a secondary analysis of data from two previous surveys where lung function of textile workers was compared with healthy Pakistani men. Spirometry was performed according to the American Thoracic Society guidelines. Independent sample t-test was used to compare the lung function parameters and multivariate linear regression was used to develop predictor equations. RESULTS: There were significant differences in lung function of textile workers (FVC: 4.1 L, FEV1: 3.3 L and FEV1/FVC: 0.8) compared to healthy Pakistani men (FVC: 3.9 L, FEV1: 4.1 L and FEV1/FVC: 1.04). ERS reference equations tended to under-diagnose abnormal lung function, 16.9% versus 25.3% (p<0.01). Predictor equations for Pakistani textile workers were also developed. CONCLUSION: Lung function of textile workers was significantly reduced compared to healthy population. Use of ERS reference equations for Pakistani textile workers may not provide appropriate interpretation.

Burden of asthma among children in a developing megacity: childhood asthma study, Pakistan.

OBJECTIVES: Global burden of childhood asthma has increased in the past few decades, particularly in low-income countries. In Pakistan, there is a lack of community-based epidemiological studies estimating the burden of asthma among children. This study determined the prevalence and predictors of asthma among children 3-17 years of age in Karachi, Pakistan. METHODS: A two-stage community-based representative cross-sectional survey was conducted in Karachi from March 2012 to April 2013 comprising 1046 children aged 3-17 years. Of 7500 clusters, 80 were randomly selected, and of these, 15 children per cluster were enrolled randomly. A translated and pre-tested version of International Study of Asthma and Allergies in Children questionnaire was administered. RESULTS: The overall prevalence of asthma among study participants was 10.2% (95% CI: 8.4-12.0). Asthma was more likely to occur among boys (adj. OR: 2.5, 95% CI: 1.6-4.0), children in the younger age group (3-7 years) (adj. OR: 2.9, 95% CI: 1.7-4.8), those living in households with ill-ventilated kitchens (adj. OR: 1.8, 95% CI: 1.1-3.1), having family history of asthma (adj. OR: 2.3, 95% CI: 1.3-3.9) and those of the Sindhi ethnicity (adj. OR: 2.2, 95% CI: 1.1-4.4). CONCLUSION: This study is the first robust evidence regarding asthma among children in Pakistan, reporting a high burden in this group. Family history, male gender, Sindhi ethnicity and ill-ventilated kitchen were identified as important predictors of asthma. Targeted preventive measures and intervention studies are required to better understand and reduce the burden of asthma among children in Pakistan.

Assessing the Feasibility of a Multifaceted Intervention Package for Improving Respiratory Health of Textile Workers: Findings From the MultiTex Pilot Study in Karachi, Pakistan.

We piloted the development and implementation of a multifaceted intervention package for improving respiratory health among textile workers using a pre-post design at six mills in Karachi. The intervention, implemented following a baseline survey (n = 498), included health and safety training of workers and managers, promotion of cotton dust control measures, and the provision of facemasks. Follow-up surveys were conducted at 1, 6, and 12 months post-intervention. Knowledge, attitude, and practice (KAP) scores and respiratory symptoms were assessed through a questionnaire and spirometry was conducted. The intervention was provided to 230 workers and led to an improvement in KAP scores that was more likely among workers with a higher educational status, spinners, smokers, those with a permanent employment status, working in morning shifts, and with ⩾5 years of textile experience. We found the intervention acceptable and feasible in these textile mills henceforth, trials are required to determine its effectiveness.

Pattern and predictors for respiratory illnesses and symptoms and lung function among textile workers in Karachi, Pakistan.

OBJECTIVES: To determine pattern and predictors for respiratory illnesses and symptoms and lung function among textile workers in Karachi, Pakistan. METHODS: This was a cross-sectional survey of 372 adult male textile workers from the spinning and weaving sections of 15 textile mills from Karachi. Data were collected from November to December 2009 through a structured, pretested questionnaire and spirometry. RESULTS: Prevalence of byssinosis was 10.5%, chronic cough 7.5%, chronic phlegm 12.9%, wheeze with shortness of breath 22.3%, shortness of breath (grade 2) 21%, chest tightness ever 33.3%; whereas, a low prevalence of asthma (4%) was identified in this population. Eight per cent had obstructive, 8% restrictive and 2% mixed pattern of lung function abnormality. After controlling for potential confounders, work in the spinning section predicts frequent wheeze (AOR=2.0; 95% CI 1.1 to 3.5), wheeze with shortness of breath (AOR=1.8; 95% CI 1.0 to 3.4), and obstructive pattern on spirometry (AOR=2.5; 95% CI 1.0 to 6.2). Prolonged duration of work predicts breathlessness grade 1 (AOR=1.8; 95% CI 1.0 to 3.1) and grade 2 (AOR=2.7; 95% CI 1.3 to 5.4), as well as decrements in Forced Expiratory Volume in the first second (FEV(1)) and FEV(1)/Forced Vital Capacity ratio. Lack of education predicts frequent wheeze (AOR=2.0; 95% CI 1.2 to 3.3), and Sindhi ethnicity predicts chest tightness apart from during cold (AOR=2.7; 95% CI 1.1 to 6.6). CONCLUSIONS: This study highlights the burden of respiratory illnesses and symptoms, and a low prevalence of asthma among textile workers in Karachi. Work in the spinning section, lack of education, prolonged duration of work and Sindhi ethnicity, were identified as important risk factors.