Clinical outcomes of bronchiectasis in India: data from the EMBARC/Respiratory Research Network of India registry.

BACKGROUND: Identifying risk factors for poor outcomes can help with risk stratification and targeting of treatment. Risk factors for mortality and exacerbations have been identified in bronchiectasis but have been almost exclusively studied in European and North American populations. This study investigated the risk factors for poor outcome in a large population of bronchiectasis patients enrolled in India. METHODS: The European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) and Respiratory Research Network of India (EMBARC-India) registry is a prospective observational study of adults with computed tomography-confirmed bronchiectasis enrolled at 31 sites across India. Baseline characteristics of patients were used to investigate associations with key clinical outcomes: mortality, severe exacerbations requiring hospital admission, overall exacerbation frequency and decline in forced expiratory volume in 1 s. RESULTS: 1018 patients with at least 12-month follow-up data were enrolled in the follow-up study. Frequent exacerbations (≥3 per year) at baseline were associated with an increased risk of mortality (hazard ratio (HR) 3.23, 95% CI 1.39-7.50), severe exacerbations (HR 2.71, 95% CI 1.92-3.83), future exacerbations (incidence rate ratio (IRR) 3.08, 95% CI 2.36-4.01) and lung function decline. Coexisting COPD, dyspnoea and current cigarette smoking were similarly associated with a worse outcome across all end-points studied. Additional predictors of mortality and severe exacerbations were increasing age and cardiovascular comorbidity. Infection with Gram-negative pathogens (predominantly Klebsiella pneumoniae) was independently associated with increased mortality (HR 3.13, 95% CI 1.62-6.06), while Pseudomonas aeruginosa infection was associated with severe exacerbations (HR 1.41, 95% CI 1.01-1.97) and overall exacerbation rate (IRR 1.47, 95% CI 1.13-1.91). CONCLUSIONS: This study identifies risk factors for morbidity and mortality among bronchiectasis patients in India. Identification of these risk factors may support treatment approaches optimised to an Asian setting.

Linoleic acid metabolite leads to steroid resistant asthma features partially through NF-κB.

Studies have highlighted the role of nutritional and metabolic modulators in asthma pathobiology. Steroid resistance is an important clinical problem in asthma but lacks good experimental models. Linoleic acid, a polyunsaturated fatty acid, has been linked to asthma and glucocorticoid sensitivity. Its 12/15-lipoxygenase metabolite, 13-S-hydroxyoctadecadienoic acid (HODE) induces mitochondrial dysfunction, with severe airway obstruction and neutrophilic airway inflammation. Here we show that HODE administration leads to steroid unresponsiveness in an otherwise steroid responsive model of allergic airway inflammation (AAI). HODE treatment to allergic mice further increased airway hyperresponsiveness and goblet metaplasia. Treatment with dexamethasone was associated with increased neutrophilic inflammation in HODE treated allergic mice; unlike control allergic mice that showed resolution of inflammation. HODE induced loss of steroid sensitivity was associated with increased p-NFkB in mice and reduced GR-α transcript levels in cultured human bronchial epithelia. In summary, HODE modifies typical AAI to recapitulate many of the phenotypic features seen in severe steroid unresponsive asthma. We speculate that since HODE is a natural metabolite, it may be relevant to the increased asthma severity and steroid insensitivity in patients who are obese or consume high fat diets. Further characterization of HODE induced steroid insensitivity may clarify the mechanisms.

Variation in the prevalence of chronic bronchitis among smokers: a cross-sectional study.

OBJECTIVE: Given the wide variations in prevalence of chronic obstructive pulmonary disease observed between populations with similar levels of exposure to tobacco smoke, we aimed to investigate the possibility of variations in prevalence of chronic bronchitis (CB) between two geographically distinct smoking populations in rural Karnataka, India. DESIGN: The Burden of Obstructive Lung Disease (BOLD) questionnaire was administered to all men aged >30 years in a cross-sectional survey. The χ(2) and Fisher's exact tests were used to compare CB prevalence in the two populations. Logistic regression was used to analyse the impact of multiple variables on the occurrence of CB. RESULTS: Two samples of 2322 and 2182 subjects were included in the study. In non-smokers, CB prevalence did not differ between the populations. However, it was significantly different between smoking populations (44.79% vs. 2.13%, P < 0.0001). Logistic regression indicated that, in addition to smoking, region, age, occupational dust exposure and type of house were associated with higher likelihood of CB. An interaction between smoking and area of residence was found (P < 0.001) and appeared to explain the effect of region (without interaction). CONCLUSION: A significant difference in CB prevalence was observed between male populations from two areas of Karnataka state, including when stratified by smoking status. No significant difference was observed between non-smokers.

Identification of a threshold for biomass exposure index for chronic bronchitis in rural women of Mysore district, Karnataka, India.

BACKGROUND & OBJECTIVES: Exposure to air pollution due to combustion of biomass fuels remains one of the significant risk factors for chronic respiratory diseases such as chronic bronchitis. There is a need to identify the minimum threshold level of biomass index that is significantly associated with chronic bronchitis. This study was undertaken to identify a threshold for biomass exposure index in a rural women population in Mysore district, south India. METHODS: A cross-sectional survey was conducted in a representative population of Mysore and Nanjangud taluks. Eight villages each from Mysore and Nanjangud were randomly selected based on the list of villages from census 2001. A house-to-house survey was carried out by trained field workers using the Burden of Obstructive Diseases questionnaire, which evaluated the biomass smoke exposure and chronic bronchitis. All the women aged above 30 yr were included in the study. RESULTS: A total of 2011 women from Mysore and 1942 women from Nanjangud participated in the study. All women were non-smoking and used biomass fuels as the primary fuel for cooking. A threshold of biomass fuel exposure of 60 was identified on multivariate analysis in Mysore district after adjusting for age, passive smoking and working in a occupational exposure to dust, as the minimum required for a significant association with chronic bronchitis. One in every 20 women in Mysore district exposed to biomass fuel exposure index of 110 or more developed chronic bronchitis. INTERPRETATION & CONCLUSIONS: The minimum threshold of biomass exposure index of 60 is necessary to have a significant risk of developing chronic bronchitis in women. The number needed to harm to develop chronic bronchitis reduces with increasing biomass exposure index and women residing in rural Nanjangud have a higher risk for developing chronic bronchitis as compared to women in Mysore.

Factors affecting 30-month survival in lung cancer patients.

BACKGROUND & OBJECTIVES: Age adjusted incidence rate of lung cancer in India ranges from 7.4 to 13.1 per 100,000 among males and 3.9 to 5.8 per 100,000 among females. The factors affecting survival in lung cancer patients in India are not fully understood. The current study was undertaken to evaluate the factors affecting survival in patients diagnosed with lung cancer attending a tertiary care cancer institute in Bangalore, Karnataka, India. METHODS: Consecutive patients with primary lung cancer attending Bangalore Institute of Oncology, a tertiary care centre at Bangalore, between 2006 and 2009 were included. Demographic, clinical, radiological data were collected retrospectively from the medical records. RESULTS: A total of 170 consecutive subjects (128 males, 42 females) diagnosed to have lung cancer; 151 non-small cell lung cancer (NSCLC) and 19 small cell lung cancer (SCLC) were included. A higher proportion of never-smokers (54.1%) were observed, mostly presenting below the age of 60 yr. Most subjects were in stage IV and III at the time of diagnosis. More than 50 per cent of patients presented with late stage lung cancer even though the duration of symptoms is less than 2 months. The 30-month overall survival rates for smokers and never-smokers were 32 and 49 per cent, respectively. No significant differences were observed in 30 month survival based on age at presentation, gender and type of lung cancer. Cox proportional hazards model identified never-smokers and duration of symptoms less than 1 month as factors adversely affecting survival. INTERPRETATION & CONCLUSIONS: Our results showed that lung cancer in Indians involved younger subjects and associated with poorer survival as compared to other ethnic population. Studies on large sample need to be done to evaluate risk factors in lung cancer patients.

Prevalence of chronic cough, chronic phlegm & associated factors in Mysore, Karnataka, India.

BACKGROUND & OBJECTIVES: Chronic cough and chronic phlegm are important indicators of respiratory morbidity, accelerated lung function decline, increased hospitalization and mortality. This study was planned to estimate the prevalence of chronic cough and phlegm in the absence of dyspneoa and wheezing and to study its associated factors in a representative population of Mysore district. METHODS: A cross-sectional survey was planned in a representative population of Mysore taluk. Eight villages were randomly selected based on the list of villages from census 2001. Trained field workers using the Burden of Obstructive Diseases questionnaire carried out a house-to-house survey. RESULTS: A total of 4333 adult subjects were enrolled in the study with 2333 males and 2000 females. The prevalence of chronic cough in the community was 2.5 per cent and that of chronic phlegm was 1.2 per cent. A significant association was observed between chronic cough and age, gender, occupation and smoking and chronic phlegm with age, gender, occupation, indoor animals and smoking. A multivariate analysis confirmed independent association of age, occupation and smoking for chronic cough and age and smoking for chronic phlegm. On sub-group analysis of males, heavy smokers had higher prevalence of chronic cough and chronic phlegm as compared to light smokers and non smokers. INTERPRETATION & CONCLUSIONS: The prevalence of chronic cough was 2.5 per cent and chronic phlegm was 1.2 per cent in the general population in Mysore which is lower than that observed in other studies. Heavy smoking was an important preventable risk factor identified in this study and efforts towards smoking cessation are crucial to achieve good respiratory health in the community.

Validation of a structured questionnaire for COPD and prevalence of COPD in rural area of Mysore: A pilot study.

BACKGROUND: The prevalence of chronic obstructive pulmonary disease (COPD) is increasing in India and there is a need to study the prevalence of COPD, particularly in the rural areas, which may be most affected due to their lifestyle. MATERIALS AND METHODS: FIRST STAGE: Validation of the questionnaire-105 consecutive patients underwent administration of the structured questionnaire and spirometry was used as a gold standard for the diagnosis of COPD. Second stage: Adults above 40 years (n = 900) in two villages of Mysore district were administered with the validated questionnaire, Knowledge and Attitude questionnaire and Fagerstorm questionnaire, to assess nicotine dependency. RESULTS: The questionnaire was found to have a sensitivity of 62.5% and specificity of 87.6% to diagnose COPD. Of the total 900 adults surveyed (Males: 453, Females: 447), the total prevalence of COPD was 7.1%. Males had a higher prevalence (11.1%) compared to females (4.5%). The prevalence of smoking was very high among men at 71.9% and all the women were nonsmokers. The prevalence of COPD was 14.7% in smokers, 19.3% had mild to moderate nicotine dependency and 12.8% were highly dependent. Of the women exposed to regular biomass fuels, the prevalence of COPD was 3.9%, which increased to 4.8% on addition of regular passive smoking. In smoking, male gender and age were significantly associated with COPD (P < 0.05). CONCLUSION: The structured questionnaire is a useful tool for the screening of COPD in field studies. Smoking and biomass fuel exposure are important risk factors for COPD.

Ruptured hydatid cyst of lung.

We report a case of 26 year old woman who had ruptured hydatid cyst of the right lung. The chest radiograph and CT features were suggestive of a ruptured hydatid cyst with detached and collapsed endocyst within the exocyst. Intraoperatively communication between cyst and bronchus could be demonstrated. Interesting CT appearance and demonstrable communication of cyst with bronchus is the reason for this case report.