Experience with treatment of pulmonary alveolar proteinosis from a tertiary care centre in north India.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a disorder characterised by accumulation of lipids and proteins in the alveoli, with the resultant symptoms ranging from indolent subclinical disease to progressive respiratory failure. METHODS: We retrospectively studied five patients with PAP managed at our center between January 2007 and April 2010, with whole lung lavage (WLL) and/or subcutaneous granulocyte macrophage-colony stimulating factor (GM-CSF) therapy. Patients undergoing WLL under general anaesthesia were supplemented with three months of GM-CSF therapy. Pre- and post-lavage symptom assessment was performed with a 10-point, symptom-based visual analogue scale. RESULTS: Their mean age was 37.6-7.0 years; there were four males. Diagnosis of PAP [idiopathic (n=3); secondary to Nocardia (n=1)] was established by surgical lung biopsy in four patients who presented with respiratory failure. Three patients with idiopathic PAP (n=3) were treated with a combination of GM-CSF and WLL; one patient with secondary PAP was treated with antibiotics alone. In another patient transbronchial lung biopsy was used to diagnose PAP and GM-CSF alone was administered. All patients were followed up for a median period of two years (range 0.5-3 years). Significant improvement was achieved in all the patients with therapeutic WLL and/or GM-CSF. CONCLUSIONS: Whole lung lavage appeared to be an effective and safe therapy in patients with PAP. Efficacy of simultaneous administration of GM-CSF and WLL in the treatment of PAP merits further study.

Diagnostic accuracy of TB-LAMP assay in patients with pulmonary tuberculosis...a case-control study in northern India.

SETTING: A tertiary care hospital in North India. OBJECTIVE: Tuberculosis (TB) remains a major public health problem in developing countries. The diagnosis of tuberculosis is still challenging in primary care settings in endemic countries like India. WHO has endorsed loop mediated isothermal amplification assay (LAMP) for TB as a replacement for smear microscopy for peripheral settings, however, more data is required to establish the specificity of this modality for the diagnosis of TB. In this study we aim to determine the diagnostic accuracy of the TB-LAMP assay in pulmonary tuberculosis. DESIGN: A total of 236 patients (117 cases suspected of TB and 119 patients with non-TB pulmonary disease) were enrolled between February to July, 2018. Microbiological workups consisting of mycobacterial smear microscopy, culture, Xpert MTB/Rif and TB-LAMP were performed. RESULTS: From 236 samples, 18 (7.6%) were excluded from the study. TB-LAMP and Xpert MTB/RIF were positive in 46 (21.1%) and 49 (22.5%) of the samples, respectively. The sensitivity of Xpert MTB/RIF and TB-LAMP, when culture was taken as a reference standard, was 90% (95%CI: 78.2-96.7) and 82% (95%CI: 68.6...91.4), respectively. The specificity, positive predictive value (PPV), and negative predictive value (NPV) of TB-LAMP assay were 96.8% (95%CI: 92.8...98.9), 89.1% (95%CI: 77.4...95.2), and 94.4% (95%CI: 90.4...96.5), respectively. CONCLUSION: The TB-LAMP assay showed a good specificity and sensitivity for detection ofM. tuberculosis in adults, however, for programmatic implementation, more studies are required to be conducted at peripheral level healthcare settings.

Interferon gamma release assay (QuantiFERON-TB Gold In Tube) in patients of sarcoidosis from a population with high prevalence of tuberculosis infection.

BACKGROUND AND OBJECTIVE: Detecting latent tubercular infection (LTBI) in sarcoidosis has important treatment implications. Traditionally tuberculin skin test (TST) is relied upon for this purpose. However, sarcoidosis is known to produce tuberculin anergy, which is not affected by high prevalence of tuberculosis (TB) infection. Interferon gamma release assays (IGRAs) have a higher sensitivity and specificity for detecting Mycobacterium tuberculosis (MTB) infection than the conventional TST as they utilize antigens specific for MTB complex. However, there is limited data regarding the performance of these tests in sarcoidosis, particularly in a setting of high population prevalence of LTBI. Herein, we studied the utility of IGRAs in the diagnostic work up of patients with sarcoidosis. PATIENTS AND METHODS: Prospectively enrolled, biopsy-confirmed, glucocorticoid naive cases of pulmonary sarcoidosis; pulmonary and extrapulmonary TB; and, healthy controls underwent TST using 0.1 mL (1 tuberculin unit) of purified protein derivative RT23, and IGRA using QuantiFERON-TB-Gold In Tube assay (QFT) in blood. For TST an induration > or =10 mm was taken as positive. QFT was performed and interpreted as per the manufacturer's instructions. RESULTS: We studied 38 patients with sarcoidosis (22 men, 16 women; mean age 42.5 years), 30 patients of TB (18 pulmonary, 12 extrapulmonary) and 30 healthy controls. Patients with sarcoidosis were more likely to have a negative TST compared to healthy controls (89.5% vs. 60%, p = 0.004) or TB (89.5% vs. 23.3%, p < 0.001). However, QFT positivity was not significantly different in sarcoidosis compared to controls (34.2% vs. 50%, p = 0.19), but was higher in TB patients as compared to sarcoidosis (60% vs. 34.2%, p = 0.03). CONCLUSIONS: There is anergy to tuberculin in sarcoidosis. However, the results of QFT are not similarly affected. QFT continues to remain positive in many patients with sarcoidosis, and thus may be more accurate to detect LTBI in these patients.

Immune responses to mycobacterial antigens in sarcoidosis: a systematic review.

From the time sarcoidosis has been described, there has always been a viewpoint that the disease is in some way related to tuberculosis (TB). Sarcoidosis is a granulomatous disease, which is likely a result of continued presentation of a poorly degradable antigen. Mycobacterium tuberculosis has been a very strong contender for this antigen. Besides the molecular studies demonstrating mycobacterial deoxyribonucleic acid (DNA) in the sarcoid tissue, assessment of immune responses against mycobacterial antigens provides a useful tool to study the role of mycobacteria in the pathogenesis of sarcoidosis. We reviewed the studies focussing on T-cell and B-cell responses to tubercular antigens in patients with sarcoidosis. Pooled data from various studies does provide a suggestive, though not unequivocal evidence in favour of mycobacteria as a cause of sarcoidosis. These findings not only reinforce the possible pathogenic role of mycobacterial antigens in sarcoidosis, but at the same time also limit the clinical utility of molecular and serological studies based on mycobacterial antigens in the differential diagnosis of TB from sarcoidosis, particularly in a country with high endemicity for TB.

Medical thoracoscopy for undiagnosed pleural effusions: experience from a tertiary care hospital in north India.

BACKGROUND AND AIMS: Medical thoracoscopy, also called pleuroscopy, has received renewed interest in the recent past for diagnostic as well as therapeutic uses. In this study, we describe our experience with thoracoscopy for undiagnosed pleural effusions. METHODS: In a retrospective analysis of thoracoscopic procedures we performed between January 2007 and December 2008, yield of thoracoscopic pleural biopsy for achieving a diagnosis in undiagnosed pleural effusions, defined as pleural effusions with adenosine deaminase (ADA) levels less than 70 IU/L and negative pleural fluid cytology for malignancy on three occasions was evaluated. Complications of thoracoscopy were also analysed. RESULTS: Overall diagnostic yield of thoracoscopic pleural biopsy was 74.3% in patients with undiagnosed pleural effusions. Pleural malignancy was diagnosed in 48.6% of patients. There was only one case of mesothelioma and the rest were due to pleural metastasis. Lung cancer and breast cancer were the most common sites of primary malignancy. Tuberculosis was diagnosed with pleural biopsy in 22.8% of patients. We had low complication rate after thoracoscopy. Only two cases of empyema were observed. CONCLUSION: Medical thoracoscopy is a safe procedure and has good diagnostic yield in patients with undiagnosed pleural effusions.

Initial experience of endobronchial silicon stents from a tertiary care centre in North India.

BACKGROUND: Central airway obstruction (CAO) is defined as obstruction of trachea and principal bronchi. Therapeutic rigid bronchoscopy with tracheobronchial stenting using silicon stents is a well established procedure in the management of such conditions. However, there is limited experience with this technique in India. METHODS: Between January 2010 and April 2010, Dumon stents were placed in four patients with CAO. Three patients had symptomatic tracheal stenosis while one patient had malignant obstruction at the carina. Rigid bronchoscopy under general anaesthesia was performed to relieve the CAO followed by placement of silicon stents. Pre- and post-stent placement symptom assessment was performed with a symptom-based visual analogue scale. RESULTS: Four patients underwent silicon stent placement in the tracheobronchial tree. Three patients had benign post-intubation tracheal stenosis and one had malignant tracheal obstruction at carina due to endobronchial growth. Significant improvement was achieved in all patients. There were no significant complications. CONCLUSIONS: Rigid bronchoscopy with silicon stent placement is an effective and suitable method of relieving the distressing symptoms due to benign or malignant airway obstruction.

Is tobacco smoking protective for sarcoidosis? A case-control study from North India.

BACKGROUND: While tobacco smoking is commonly believed to be negatively associated with the occurrence of sarcoidosis, the relationship of environmental tobacco smoke (ETS) exposure with sarcoidosis is largely un-explored. We studied the impact of active smoking and ETS exposure on disease severity in newly diagnosed cases of sarcoidosis from India. METHODS: Data on demographic variables, smoking habits and exposure to environmental tobacco smoke (ETS) among non-smoker sarcoidosis patients was collected prospectively. Presence of smoking and ETS exposure were compared among cases and controls. Among the sarcoidosis patients, clinical manifestations, radiology, spirometry and histopathological grading of lung biopsy were compared between the smokers vs. non-smokers and ETS exposed vs. not-exposed. RESULTS: We studied 98 newly diagnosed cases of sarcoidosis and 196 age, sex and religion- matched healthy volunteers. The study group comprised of 62 (63%) men and 36 (37%) women. The prevalence of smoking was similar in cases and controls (12.2% vs. 15.3%, p = 0.48). Among the never smoker patients with sarcoidosis, 20 (23%) reported ETS exposure vis-a-vis 57 (34%) in the matched controls. A conditional logistic regression analyses showed insignificant negative association with active smoking (OR 0.75; 95% CI, 0.35-1.56) or ETS exposure (OR 0.58; 95% CI, 0.32-1.06) after adjusting for age, gender, religion, and education. There were no differences in the clinical manifestations, radiological staging, spirometry and histopathological grading of lung biopsy in any of the group comparisons studied. CONCLUSION: Smoking or ETS exposure may not have significant negative association with sarcoidosis. Also, tobacco smoke might not have any effect on the clinical behavior or disease severity in sarcoidosis. The belief that smoking is protective for sarcoidosis is not substantiated in this study and appears to be misfounded.

COPD exacerbation rates are higher in non-smoker patients in India.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is common among non-smokers exposed to solid fuel combustion at home. Different clinical characteristics in these patients may have significant therapeutic and prognostic implications.METHODS: We used medical record review and a questionnaire among COPD patients at 15 centres across India to capture data on demographic details, different types of exposures and clinical characteristics. Chest radiography and pulmonary function testing were performed in all 1984 cases; C-reactive protein and exhaled breath nitric oxide were measured wherever available.RESULTS: There were 1388 current or ex-smokers and 596 (30.0%) non-smokers who included 259 (43.5%) male and 337 (56.5%) female patients. Sputum production was significantly more common in smokers with COPD (P < 0.05). The frequency of acute symptomatic worsening, emergency visits and hospitalisation were significantly higher (P < 0.05) in non-smokers with COPD; however, intensive care unit admissions were similar in the two groups. There was no significant difference with respect to the use of bronchodilators, inhalational steroids or home nebulisation among smoker and non-smoker patients. The mean predicted forced expiratory volume in 1 sec in smokers (43.1%) was significantly lower than in non-smokers (46.5%).CONCLUSION: Non-smoker COPD, more commonly observed in women exposed to biomass fuels, was characterised by higher rate of exacerbations and higher healthcare resource utilisation.

Aspergillus hypersensitivity and allergic bronchopulmonary aspergillosis in patients with bronchial asthma: systematic review and meta-analysis.

BACKGROUND: The prevalence of Aspergillus hypersensitivity (AH) and allergic bronchopulmonary aspergillosis (ABPA) in bronchial asthma is reported differently in various studies. OBJECTIVE: To determine the prevalence of AH and ABPA in asthma using a systematic review. METHODS: We searched the MEDLINE and EMBASE databases for studies published from 1965 to 2008 and included studies that report the prevalence of AH/ABPA in asthma. We calculated the proportions with 95% confidence interval (CI) to assess the prevalence of AH/ABPA in the individual studies and pooled the results using a random effects model. RESULTS: Our search yielded 21 eligible studies. The prevalence of AH in bronchial asthma was 28% (95%CI 24-34), and was higher with an intradermal test vs. a prick test (28.7% vs. 24.8%, P = 0.002), but did not vary with the type of antigen used (indigenous or commercial). The prevalence of ABPA in bronchial asthma and Aspergillus-hypersensitive bronchial asthma was respectively 12.9% (95%CI 7.9-18.9) and 40% (95%CI 27-53). There was a wide variation in the criteria used for the diagnosis of ABPA. There was significant statistical heterogeneity assessed by the I(2) test and Cochran Q statistic in all the outcomes. CONCLUSIONS: There is a high prevalence of AH and ABPA in patients with bronchial asthma. Careful screening should therefore be performed in all patients with bronchial asthma. Intradermal tests are more sensitive than prick tests for the diagnosis of AH. Finally, there is a need to adopt a uniform methodology and criteria for the diagnosis of AH/ABPA.

Is the SMART approach better than other treatment approaches for prevention of asthma exacerbations? A meta-analysis.

BACKGROUND AND AIMS: The combination of inhaled corticosteroids (ICS) and long-acting beta2 agonists (LABA) has been used as a single inhaler both for maintenance and reliever therapy in asthma, the SMART approach. The administration of additional CS with each reliever inhalation in response to symptoms is expected to provide better control of airway inflammation. The aim of this meta-analysis was to evaluate the efficacy and safety of the SMART approach versus other approaches in the management of asthma in preventing asthma exacerbations. METHODS: We searched the MEDLINE and EMBASE databases for studies that have reported exacerbations in the SMART group versus the control group. We calculated the odds ratio (OR) and 95% confidence intervals (CI) to assess the exacerbations in the two groups and pooled the results using a random-effects model. RESULTS: Our search yielded eight studies. The use of SMART approach compared to fixed-dose ICS-LABA combination significantly decreased the odds of a severe exacerbation (OR 0.65; 95% CI, 0.53-0.80) and severe exacerbation requiring hospitalization/ER treatment (OR 0.69; 95% CI, 058-0.83). The use of SMART approach compared to fixed-dose ICS also significantly decreased the odds of a severe exacerbation (OR 0.52; 95% CI, 0.45-0.61) and severe exacerbation requiring medical intervention (OR 0.52; 95% CI, 0.42-0.65). The occurrence of adverse events was similar in the two groups. There was some evidence of statistical heterogeneity. CONCLUSIONS: The SMART approach using formoterol-budesonide is superior in preventing exacerbations when compared to traditional therapy with fixed dose ICS or ICS-LABA combination without any increase in adverse events.

Tubercular osteomyelitis of the clavicle: a report of four cases.

We report the clinicoradiological features of tuberculosis in the clavicle in 4 patients. The patients' ages ranged from 9 months to 29 years. All patients were managed with antitubercular drug therapy for one year and one underwent surgical debridement and curettage as well. Clinicians should be aware of the varied presentation (pain, non-healing ulcer, abscess, multifocal osteoarticular tuberculosis) of this condition. With the worldwide resurgence of tuberculosis, clinicians should maintain a high index of suspicion. The diagnosis of osteoarticular tuberculosis is usually made on clinico-radiological features.

Monitoring treatment response in chronic pulmonary aspergillosis: role of clinical, spirometric and immunological markers.

OBJECTIVES: The treatment response in chronic pulmonary aspergillosis (CPA) is usually assessed based on the improvement in clinical and imaging findings. Herein, we evaluate serum Aspergillus fumigatus-specific IgG, serum galactomannan, weight change, and lung function for assessing treatment response in subjects with CPA. METHODS: We categorized treatment response as favourable (improved or stable clinical response with radiologically improved or stable disease) or unfavourable (worsening of symptoms or radiological progression) after 6 months of treatment with antifungal azoles. We measured A. fumigatus-specific IgG, serum galactomannan, weight, and lung function at baseline, 3 months, and 6 months in those with favourable and unfavourable treatment response. RESULTS: One hundred and twenty-six consecutive treatment-naïve subjects (53.2% (67/126) males; mean ± SD age, 42.3 ± 14.7 years) with CPA were included. One hundred and six and 20 were classified as having favourable and unfavourable response, respectively. After 6 months of treatment, the decline in serum A. fumigatus-specific IgG (n = 119) was similar in those with favourable or unfavourable response (mean ± SD, -26.3 ± 45.5 mgA/L vs. -3.4 ± 65.6 mgA/L; p 0.20). There was no significant change in the serum galactomannan (favourable vs. unfavourable: mean ± SD, -0.11 ± 2.8 vs. -0.62 ± 2; p 0.92) or FEV1 (favourable vs. unfavourable: mean ± SD, 24 ± 250 mL vs. -62 ± 154 mL; p 0.19) after 6 months of treatment. There was significant loss of weight (mean ± SD, -2.5 ± 4.5 kg) in subjects with unfavourable response. CONCLUSION: Serum A. fumigatus-specific IgG and serum galactomannan inconsistently decrease following treatment and may not be useful indicators for monitoring treatment response in CPA. Similarly, there is little change in pulmonary function following treatment. A gain in body weight is seen in those with favourable response.

Sub-national TB prevalence surveys in India, 2006-2012: Results of uniformly conducted data analysis.

SETTING: Community based tuberculosis (TB) prevalence surveys in ten sites across India during 2006-2012. OBJECTIVE: To re-analyze data of recent sub-national surveys using uniform statistical methods and obtain a pooled national level estimate of prevalence of TB. METHODS: Individuals ≥15 years old were screened by interview for symptoms suggestive of Pulmonary TB (PTB) and history of anti-TB treatment; additional screening by chest radiography was undertaken in five sites. Two sputum specimens were examined by smear and culture among Screen-positives. Prevalence in each site was estimated after imputing missing values to correct for bias introduced by incompleteness of data. In five sites, prevalence was corrected for non-screening by radiography. Pooled prevalence of bacteriologically positive PTB was estimated using Random Effects Model after excluding data from one site. Overall prevalence of TB (all ages, all types) was estimated by adjusting for extra-pulmonary TB and Pediatric TB. RESULTS: Of 769290 individuals registered, 715989 were screened by interview and 294532 also by radiography. Sputum specimen were examined from 50 852 individuals. Estimated prevalence of smear positive, culture positive and bacteriologically positive PTB varied between 108.4-428.1, 147.9-429.8 and 170.8-528.4 per 100000 populations in different sites. Pooled estimate of prevalence of bacteriologically positive PTB was 350.0 (260.7, 439.0). Overall prevalence of TB was estimated at 300.7 (223.7-377.5) in 2009, the mid-year of surveys. Prevalence was significantly higher in rural compared to urban areas. CONCLUSION: TB burden continues to be high in India suggesting further strengthening of TB control activities.

An unusual association between Mycobacterium tuberculosis and Aspergillus fumigatus.

Allergic bronchopulmonary aspergillosis (ABPA) is rarely described outside the setting of asthma or cystic fibrosis. The occurrence of ABPA in other structural lung diseases included scars of old healed pulmonary tuberculosis (PTB) is also unknown. In this case, we report a 62-year old lady treated for PTB 40 years ago who presented with increasing dyspnea on exertion, cough with expectoration of blackish brown mucus plugs and wheezing. High-resolution computed tomographic scan of the thorax showed parenchymal fibrosis and volume loss in left upper lobe while central bronchiectasis, mosaic attenuation, centrilobular nodules with a tree-in-bud pattern were observed in the other lobes. Investigations revealed a diagnosis of ABPA. The patient was treated with prednisolone and showed a significant response. We review the current literature on this unusual association of previous and cured TB with ABPA, and also discuss the hypothesis of this possible relationship.

Clinical characteristics and outcomes of empyema thoracis in 117 patients: a comparative analysis of tuberculous vs. non-tuberculous aetiologies.

BACKGROUND: Empyema thoracis remains a major problem in developing countries. Clinical outcomes in tuberculous empyema are generally believed to be worse than in non-tuberculous aetiologies because of the presence of concomitant fibrocavitary parenchymal disease, frequent bronchopleural fistulae and poor general condition of patients. We performed a prospective study over a 2-year period with the objective of comparing the clinical characteristics and outcomes of patients with tuberculous vs. non-tuberculous empyema. METHODS: Prospective study of all cases of non-surgical thoracic empyema seen at a tertiary care centre in North India over a 2-year period. A comparative analysis of clinical characteristics, treatment modalities and outcomes of patients with tuberculous vs. non-tuberculous empyema was carried out. Factors associated with poor outcomes were analysed using multivariate logistic regression. RESULTS: One hundred and seventeen cases of empyema were seen in the study period of which 95 had non-tuberculous and 41 had tuberculous empyema. Malnutrition and bronchopleural fistulae (BPF) were more common and duration of symptoms longer in the tuberculous empyema group. Time to resolution of fever, duration of pleural drainage and pleural thickening >2 cm were significantly greater as well. Eight (10.5%) patients with non-tuberculous empyema and four (9.8%) with tuberculous empyema succumbed. Presence of a BPF was significantly associated with poor outcomes on multivariate logistic regression analysis. CONCLUSIONS: Tuberculous empyema remains a common cause of thoracic empyema in India though it ranked second amongst all causes of empyema after community acquired lung infections in this study. Tuberculous empyema is associated with longer duration of symptoms, greater duration of pleural drainage and more residual pleural fibrosis.

Is right heart thromboemboli another indication for thrombolysis?

Pulmonary embolism (PE) is a common and a potentially life-threatening disease. Diagnosis is challenging because the signs and symptoms are non-specific. Moreover treatment of PE is shrouded in controversy. Even at presentation the role of thrombolysis in managing patients with PE remains unclear. In those patients with right heart thromboemboli, thrombolysis is usually suggested, but the evidence remains unclear. We report a 34-year-old man who was diagnosed with right heart thromboemboli on echocardiography and was successfully managed with thrombolysis and anticoagulation. We also review the current published work on the management of patients with right heart thromboemboli.

Intrapleural fibrinolysis in clotted haemothorax.

The immediate treatment of haemothorax is thoracostomy tube insertion. One complication of haemothorax is retained blood and if improperly managed, this can lead to complications such as empyema and fibrothorax. The ideal management of clotted haemothorax is a matter of controversy. Video-assisted thoracoscopic surgery (VATS) is believed to be the best available modality for the management of clotted haemothorax. However, VATS is not routinely available in many centres. One easily available and effective alternative to VATS is the use of intrapleural fibrinolysis. We report the successful management of a post-traumatic clotted haemaothorax in a 34-year-old man, using intrapleural instillation of streptokinase, and review the literature on the management of clotted haemothorax.

Experience with paraquat poisoning in a respiratory intensive care unit in North India.

INTRODUCTION: Paraquat poisoning is an uncommon entity in India. We report our experience of managing five patients with paraquat poisoning using immunosuppressive therapy. METHODS: Retrospective analysis of 84 patients admitted with a diagnosis of poisoning over the last eight years was performed. The data were presented in a descriptive fashion. RESULTS: Five (5.9 percent) out of the 84 patients were admitted with a diagnosis of paraquat poisoning. All patients were mechanically ventilated. All patients had hepatic failure with median peak bilirubin being 22.1 +/- 15.1 mg/dL (range 8.4-45.5). Four of the five patients had renal failure (median peak creatinine 3.8 +/- 1.5 mg/dL; range 3.4-11.1) requiring renal replacement therapy. All patients were treated with intravenous methylprednisolone 15 mg/kg/day for three consecutive days and intravenous cyclophosphamide 10 mg/kg/ day for two consecutive days, followed by intravenous dexamethasone 4 mg thrice a day until recovery or death. Two out of the five patients survived. Three died because of severe acute respiratory distress syndrome and multiorgan dysfunction syndrome. CONCLUSION: Paraquat poisoning is an uncommon entity in India, and is associated with a high mortality rate. There is a potential role for immunosuppressive therapy in patients with moderate to severe poisoning.

Prevalence and risk factors for bronchial asthma in Indian adults: a multicentre study.

BACKGROUND: There is limited information on field epidemiology of bronchial asthma in Indian adults. OBJECTIVES: To estimate prevalence of bronchial asthma in different regions of India and to define risk factors influencing disease prevalence. METHODS: A field study was conducted at Chandigarh, Delhi, Kanpur and Bangalore through a two stage stratified (urban/ rural) sampling and uniform methodology using a previously validated questionnaire. Asthma was diagnosed if the respondent answered affirmatively both to (a) whistling sound from chest, or chest tightness, or breathlessness in morning, and (b) having suffered from asthma, or having an attack of asthma in the past 12 months, or using bronchodilators. Besides demographic data, information on smoking habits, domestic cooking fuel used, atopic symptoms, and family history suggestive of asthma was also collected. Univariate and multivariate logistic regression modelling was performed to calculate odds ratio of various potential risk factors. RESULTS: Data from 73605 respondents (37682 men, 35923 women) were analysed. One or more respiratory symptoms were present in 4.3-10.5% subjects. Asthma was diagnosed in 2.28%, 1.69%, 2.05 and 3.47% respondents respectively at Chandigarh, Delhi, Kanpur and Bangalore, with overall prevalence of 2.38%. Female sex, advancing age, usual residence in urban area, lower socio-economic status, history suggestive of atopy, history of asthma in a first degree relative, and all forms of tobacco smoking were associated with significantly higher odds of having asthma. CONCLUSION: Prevalence estimates of asthma in adults in this study, although lower than several previously reported figures, point to a high overall national burden of disease.

Household environmental tobacco smoke exposure, respiratory symptoms and asthma in non-smoker adults: a multicentric population study from India.

BACKGROUND: Exposure to environmental tobacco smoke (ETS) is a risk factor for childhood asthma. Its association with asthma in adults is less clear. METHODS: In a multicentric population study on asthma prevalence in adults, specific enquiries were made into childhood and adulthood exposure to household ETS, and its relationship with asthma diagnosis were analysed. RESULTS: From a total of 73605 respondents, 62109 were studied after excluding current or past smokers. Overall observed prevalence of asthma was 2.0% (men 1.5%,women 2.5%, p < 0.001). Of all asthma patients, history of ETS exposure was available in 48.6 percent. Prevalence of asthma in the ETS exposed subjects was higher compared to non-exposed individuals (2.2% vs 1.9%, p < 0.05). Multiple logistic regression analysis showed a higher risk of having asthma in persons who were exposed to ETS compared to those not exposed (odds ratio [OR] 1.22, 95% CI 1.08-1.38) after adjusting for age, gender, usual residence, exposure to biomass fuels and atopy. Stratification of ETS exposure revealed that exposure during childhood and both during childhood and adulthood were significantly associated with asthma prevalence. Exposure only in adulthood was not a significant risk factor (OR 1.13, 95% CI 0.95-1.33). Persons reporting combined environmental tobacco smoke exposure from parents during childhood and spouse during adulthood had highest risk of having asthma (OR 1.69, 95% CI 1.38-2.07). Environmental tobacco smoke exposure was also significantly associated with prevalence of respiratory symptoms such as wheezing, cough and breathlessness. CONCLUSIONS: Environmental tobacco smoke exposure during childhood is an important risk factor for asthma and respiratory symptoms in non-smoking adults.