Richa Mittal

GOLD Classification of COPD: Discordance in Criteria for Symptoms and Exacerbation Risk Assessment

ABSTRACT The new A-B-C-D Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification of severity of chronic obstructive pulmonary disease (COPD) is based on combined symptoms and exacerbation risk assessment. The assumed equivalence between dyspnoea modified Medical Research Council (mMRC) grade ≥2 and COPD Assessment Test (CAT) score ≥ 10 to identify more symptoms has been questioned. Whether the exacerbation risk assessment criteria, old GOLD spirometry staging and frequency of exacerbations, are equivalent has not been examined. We evaluated the extent of agreement between these alternative criteria and whether it improved by redefining the equivalence between mMRC grade and CAT score. CAT scores, mMRC grades of dyspnoea, frequency of exacerbations and spirometry stages were computed in 400 patients with COPD. Receiver operating characteristic curve was analysed to determine the best CAT score to identify more symptoms. CAT scores across mMRC grades and the frequency of exacerbations across spirometry stages showed substantial overlaps. The symptoms criteria gave discordant classification in 88 (22%) patients (kappa 0.62) and the exacerbation risk assessment criteria in 181 (45%) patients (kappa 0.12). A CAT score of ≥10 had 82% sensitivity but 24% specificity to identify mMRC grade ≥ 2, while a score of 17 had 98% specificity but a low sensitivity of 52% and did not improve the agreement. We conclude that symptoms and exacerbation risk assessment criteria of the new GOLD classification yield discordant group categorisations. Lack of any satisfactory equivalence between CAT score and mMRC grades implies that the former cannot be used alone. Using the higher of mMRC ≥ 2 and CAT score ≥ 17 to identify more symptoms would avoid discordant categorisation.

Multivariate Rotation Design for Population Mean in Sampling on Successive Occasions

This article deals with the problem of estimation of the population mean in presence of multi-auxiliary information in two occasion rotation sampling. A multivariate exponential ratio type estimator has been proposed to estimate population mean at current (second) occasion using information on p-additional auxiliary variates which are positively correlated to study variates. The theoretical properties of the proposed estimator are investigated along with the discussion of optimum replacement strategies. The worthiness of proposed estimator has been justified by comparing it to well-known recent estimators that exist in the literature of rotation sampling. Theoretical results are justified through empirical investigations and a detailed study has been done by taking different choices of the correlation coefficients. A simulation study has been conducted to show the practicability of the proposed estimator.

A class of estimators for population median in two occasion rotation sampling

The present work deals with the problem of estimation of finite population median at current occasion, in two occasion successive (rotation) sampling. A class of estimators has been proposed for the estimation of population median at current occasion, which includes many existing estimators as a particular case. Asymptotic properties including the asymptotic convergence of proposed class of estimators are elaborated. Optimum replacement strategies are also discussed. The proposed class of estimators at optimum condition is compared with the sample median estimator when there is no matching from the previous occasion as well as with some other members of the class. Theoretical results have been justified through empirical interpretation with the help of some natural populations. 2000 AMS Classification: 62D05

Searching Effective Rotation Patterns for Population Median using Exponential Type Estimators in Two-Occasion Rotation Sampling

ABSTRACT The present article is an attempt to explore the rotation patterns using exponential ratio type estimators for the estimation of finite population median at current occasion in two occasion rotation sampling. Properties of the proposed estimators including the optimum replacement strategies have been elaborated. The proposed estimators have been compared with sample median estimator when there is no matching from previous occasion as well with the ratio type estimator proposed by Singh et al. (2007) for second quantile. The behaviors of the proposed estimators are justified by empirical interpretations and validated by means of simulation study with the help of some natural populations.

Calcified pulmonary consolidations in pulmonary alveolar microlithiasis: Uncommon computed tomographic appearance of a rare disease

Lung India • Volume 34 • Issue 3 • May June 2017 297 Mantoux test was negative. Pulmonary function test studies revealed severe restrictive lung disease with a forced vital capacity (FVC) of 1.4 L (43% predicted) and a forced expiratory volume in 1 s (FEV1) of 1.3 L (46% predicted). The FEV1/FVC ratio was 93%. The total lung capacity was 2.25 L (51% predicted). Diffusing capacity of the lung for carbon monoxide was 29%. The patient desaturated on a 6-minute walk test with the pulse oximetry showing a fall in arterial oxygen saturation from 94% at rest to 86% on walking. The 6-minute walk distance was 60 m. Serum Angiotensin-converting enzyme was elevated (99 U/ml). Fiberoptic bronchoscopic examination revealed a normal appearing tracheobronchial tree. Bronchoalveolar lavage (BAL) fluid was negative for acid-fast bacilli and other pathogens with an unremarkable cytology. A transbronchial lung biopsy from the right lower lobe was noncontributory due to inadequate tissue. Two-dimensional and color Doppler echocardiography showed normal wall motion, chamber sizes, and cardiac valves, a left ventricular ejection fraction of 61% and an estimated high mean pulmonary artery pressure of 39 mm Hg.

A fresh approach for intercession of nonresponse in multivariate longitudinal designs

ABSTRACT The occurrence of nonresponse is very much plebeian in surveys, which troubles the analysis, and hence, an inappropriate inference is left out. To counterbalance the sour effects of the incompleteness, fresh imputation techniques have been proposed with the aid of multi-auxiliary variates for the estimation of population mean on successive waves. Properties of the proposed estimators have been elaborated, and they have been compared with the work of Priyanka et al. (2015). Detailed simulation study is carried out to substantiate the empirical and theoretical results. Several possible cases have been addressed in which nonresponse can occur.

Sequential occurrence of combined pulmonary fibrosis and emphysema syndrome in a non-smoker female patient.

The combined pulmonary fibrosis and emphysema (CPFE) syndrome is a unique and an under‐recognized disorder characterized by emphysema in the upper lobes and interstitial fibrosis in the lower lobes of the lung. It occurs predominantly in males and almost exclusively in smokers. This rare combination of a restrictive and an obstructive mechanical defect carries a poorer prognosis than either of the two components. We present a case of CPFE syndrome in a non‐smoker female patient who developed lower lobe emphysema subsequent to development of interstitial fibrosis. The case was remarkable for the extreme rarity of several presenting features, namely, a lower lobe occurrence of emphysema subsequent to pre‐existent interstitial fibrosis, female gender and absence of a history of smoking.

Tropical pulmonary eosinophilia: effect of addition of corticosteroids after failure of diethylcarbamazine therapy

Successful response in diethylcarbamazine (DEC) therapy in tropical pulmonary eosinophilia (TPE) is not universal with a 20-40% failure rates in chronic cases. Corticosteroids have been used in such patients. However, their role in management remains ill-defined. A patient of TPE with incomplete clinical, haematological and physiological response to a standard 3 weeks DEC therapy received additional corticosteroids for the next two cycles, after which complete remission occurred. However, there was a relapse two months later with evidence of a chronic state requiring further treatment with corticosteroids with good response.

Occupational bronchiolitis induced by cotton dust exposure in a nonsmoker

The most well-known disease caused by cotton dust is byssinosis though it is also associated with chronic obstructive airways disease, and very rarely, interstitial lung disease. Obliterative bronchiolitis has never been reported in this setting. We report a 63-year-old, nonsmoker male, who presented with complaints of cough and exertional dyspnoea for 10 years. He had worked in textile industry for 35 years and symptoms had persisted even after quitting. Examination revealed prolonged expiration with expiratory wheeze, and pulmonary function tests revealed severe airflow limitation with air trapping and impaired diffusion capacity. Arterial blood gas analysis showed type I respiratory failure. A high resolution computed tomogram of the chest showed bilateral centrilobular nodules with tree-in-bud pattern and areas of air trapping. A diagnosis of obliterative bronchiolitis induced by cotton dust exposure was established on the basis of the occupational history and the characteristic radiological signs.