Jun-Jun Yeh

Asthma increases pulmonary thromboembolism risk: a nationwide population cohort study.

Studies on the association between asthma and pulmonary thromboembolism are considerably limited. We investigated whether pulmonary embolism is associated with asthma using a nationwide cohort study. We identified 31 356 patients with newly diagnosed asthma in 2002–2008 and 125 157 individuals without asthma randomly selected from the general population, frequency matched by age, sex and index year using the National Health Insurance Research Database. Both cohorts were followed-up until the end of 2010 to measure the incidence of pulmonary embolism. Cox proportional hazards regression analysis was used to measure the hazard ratio of pulmonary embolism for the asthmatic cohort, compared with the nonasthmatic cohort. We followed 186 182 person-years for asthmatic patients and 743 374 person-years for nonasthmatic subjects. The hazard ratio of pulmonary embolism was 3.24 for the asthmatic cohort, compared with the nonasthmatic cohort after adjusting for sex, age, comorbidities and oestrogen supplementation. The risk of developing pulmonary embolism significantly increased with the increased frequency of asthma exacerbation and hospitalisation. This nationwide cohort study suggests that the risk of developing pulmonary embolism is significantly increased in asthmatic patients compared to the general population. Frequent asthma exacerbation and hospitalisation are significantly associated with pulmonary embolism risk. Risk of pulmonary embolism in an asthmatic cohort was 3.24-fold compared with a nonasthmatic cohort http://ow.ly/rHEsF

Predicting Chemotherapy Response to Paclitaxel-Based Therapy in Advanced Non-Small-Cell Lung Cancer with P-Glycoprotein Expression

Background: It was reported that multidrug resistance gene 1 (MDR1) encoding human P-glycoprotein (Pgp) may play an important role in multidrug resistance of lung cancer. Therefore, before initiating chemotherapy, it is important to accurately determine the presence of Pgp in lung cancer, to achieve a satisfactory chemotherapy response. Objectives: The aim of this study was to compare immunohistochemical analyses of Pgp expression and response to paclitaxel in non-small-cell lung cancer (NSCLC). Methods: Before chemotherapy with paclitaxel, 50 patients with stage IIIb or IV NSCLC were enrolled in this study. Immunohistochemical analyses were performed on multiple nonconsecutive sections of the biopsy specimens to determine Pgp expression. Chemotherapy response was evaluated in the 3rd month after completion of treatment by clinical and radiological methods. Results: All of the 28 (100%) cases with good response had negative Pgp expression and 15 of the 22 (68%) cases with poor response had positive Pgp expression (p < 0.05). No significant differences were found for other prognostic factors (age, sex, body weight loss, performance status, tumor cell type, and tumor stage) between good response and poor response groups. Conclusions: Although Pgp expression in NSCLC does not fully predict chemotherapy response to paclitaxel-based therapy, detection of Pgp expression will aid in planning paclitaxel-based therapy for patients with advanced NSCLC. Further studies with a larger number of patients and a longer time of follow-up are necessary to confirm our findings.

Comparison of chemotherapy response with P-glycoprotein, multidrug resistance-related protein-1, and lung resistance-related protein expression in untreated small cell lung cancer.

The aim of this study was to investigate the expression of P-glycoprotein (Pgp), multidrug resistance-related protein-1 (MRP1), and lung resistance-related protein (LRP) in response to chemotherapy in untreated small cell lung cancer (SCLC). Immunohistochemical analyses were performed on multiple nonconsecutive sections of biopsy specimens to detect Pgp, MRP1, and LRP expression in 40 patients with SCLC before chemotherapeutic induction. Response to chemotherapy was evaluated by clinical and radiological methods. The patients were divided into a good response group (n = 20) and a poor response group (n = 20). No significant differences in prognostic factors (Karnofsky performance status, tumor size, or tumor stage) were found between the two groups of patients. The difference in positive Pgp and MRP1 expressions between the good and poor response groups was significant. However, the difference in LRP expression was not significant. We conclude that chemotherapy response of patients with SCLC was related to either Pgp or MRP1 but not LPR expression.

Meta-analysis: Comparison of F-18 Fluorodeoxyglucose-Positron Emission Tomography and Bone Scintigraphy in the Detection of Bone Metastasis in Patients with Lung Cancer

RATIONALE AND OBJECTIVES The aim of this review was to evaluate the diagnostic properties of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) or PET/computed tomography (CT) and bone scintigraphy in the detection of osseous metastases in patients with lung cancer. MATERIALS AND METHODS MEDLINE was searched for relevant original articles published between January 1995 and August 2010. Inclusion criteria were as follows: FDG-PET or PET/CT and bone scintigraphy was carried out to detect bone metastases in patients with lung cancer, sufficient data were presented to construct a 2 × 2 contingency table, and histopathologic analysis and/or close clinical and imaging follow-up and/or radiographic confirmation by multiple imaging modalities was used as the reference standard. Two reviewers independently extracted data related to research design, sample size, imaging techniques, technical characteristics, reference standards, methods of imaging interpretation, and totals of true-positives, false-positives, true-negatives, and false-negatives. Stata was used to obtain per patient and per lesion pooled estimates of sensitivity, specificity, and positive and negative likelihood ratios, and areas under summary receiver-operating characteristic curves (AUCs) were calculated. RESULTS The pooled patient-based sensitivity of FDG-PET or PET/CT was 0.93 (95% confidence interval [CI], 0.88-0.96), specificity was 0.95 (95% CI, 0.91-0.98), and the AUC was 0.94. The pooled sensitivity of bone scans was 0.87 (95% CI, 0.79-0.93), specificity was 0.82 (95% CI, 0.62-0.92), and the AUC was 0.91. The pooled lesion-based sensitivity of FDG-PET or PET/CT was 0.93 (95% CI, 0.84-0.97), specificity was 0.91 (95% CI, 0.80-0.96), and the AUC was 0.97. The pooled sensitivity of bone scans was 0.92 (95% CI, 0.87-0.95), specificity was 0.57 (95% CI, 0.09-0.95), and the AUC was 0.92. CONCLUSIONS Although FDG-PET or PET/CT has higher sensitivity and specificity than bone scintigraphy, further research with a less biased design is needed to determine the most efficacious imaging modality for the detection of metastatic lung cancer.

The Association Between Malignancy and End-stage Renal Disease in Taiwan

OBJECTIVE Patients with end-stage renal disease are suggestive to have a higher risk for the development of some kinds of cancer. The aim of this study is to evaluate the possible association between malignancy and end-stage renal disease in Taiwan. METHODS We used the data of the National Health Insurance system of Taiwan to assess this issue. The end-stage renal disease cohort contained 21 817 patients, and each patient was randomly frequency-matched with two people from the general population without end-stage renal disease based on their age and sex. The Cox proportional hazard regression analysis was conducted to estimate the effects of end-stage renal disease on the cancer risk. RESULTS In patients with end-stage renal disease, the risk of developing overall cancer was significantly higher than the normal healthy subjects (adjusted hazard ratio = 1.64, 95% confidence interval = 1.54-1.74). This was also true when we analyzed males and females separately. For individual cancer, the risks for developing urinary tract cancers, liver cancer and breast cancer among patients with end-stage renal disease were significantly higher. On the contrary, lung, prostate and esophageal cancer risks were significantly lower when compared with the normal healthy subjects. CONCLUSIONS Our study found Taiwanese patients with end-stage renal disease to have a higher risk to develop urinary tract, liver and breast cancer. We unexpectedly discovered these patients to have a lower risk to get lung, prostate and esophageal cancer.

Tuberculosis increases the subsequent risk of acute coronary syndrome: a nationwide population-based cohort study.

OBJECTIVE To evaluate the effects of pulmonary tuberculosis (PTB) on the risk of subsequent acute coronary syndrome (ACS) development. METHODS The incidence and risk factors of ACS were investigated in 10 168 newly diagnosed tuberculosis (TB) patients from Taiwans National Health Insurance Research Database between 1997 and 2010, and 40 672 controls without TB from the general population. The follow-up period ran from the diagnosis of new TB to the date of the ACS event, censoring or 31 December 2010. RESULTS During the follow-up period, the overall incidence of ACS was higher in TB patients than in non-TB patients (2.10 vs. 1.51 per 1000 person-years). The incidence of ACS increased by 40% in TB patients after adjusting for age, sex and co-morbidities. Male sex, age, hypertension and diabetes were independent factors for the risk of ACS development. The probability of ACS increased in the years following the TB diagnosis. CONCLUSION This nationwide population-based cohort study provides compelling evidence that TB patients are at higher risk of developing ACS, and that the risk increases with age. Clinicians should be aware of this and strive to reduce ACS risk factors in TB patients.

Potential value of dual-time-point 18F-FDG PET compared with initial single-time-point imaging in differentiating malignant from benign pulmonary nodules: A systematic review and meta-analysis

We performed a meta-analysis to assess the potential value of dual-time-point (DTP) imaging as compared with initial single-time-point (STP) scanning with 18F-fluorodeoxyglucose (18F-FDG) PET in differentiating malignant from benign single pulmonary nodules. Data on the performance of DTP 18F-FDG PET imaging in assessing lung nodules were extracted from articles of prospective or retrospective original research published between January 2001 and April 2010. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool was used to assess the quality of study methodology. Heterogeneity in the results of the studies was assessed, and summary receiver operating characteristic (SROC) curves were constructed. Eleven studies comprising a total of 788 patients who underwent initial scanning, 778 of whom also underwent DTP imaging, were included in the final analysis. The quality of study methodology was judged to be moderate. Substantial heterogeneity in the results of the studies, with inconsistency (I2) index values above 85%, reflected important differences in study methods and populations, including varying lesion sizes, 18F-FDG avidity, uptake interval for delayed imaging, and threshold for positive result on DTP imaging. SROC curve analysis revealed a statistically nonsignificant trend toward higher sensitivity with DTP imaging, at moderate levels of specificity, when compared with initial STP scanning. The area under the curve (SE) values for DTP and initial STP imaging were 0.839 (0.079) and 0.757 (0.074), respectively. Although the results of our analysis do not support the routine use of DTP imaging with 18F-FDG PET in the differential diagnosis of pulmonary nodules, this technique may provide additional information in selected cases with equivocal results from initial scanning. Further prospective research is required to better define the potential benefits of DTP 18F-FDG PET imaging.

Meta-analysis study of lymph node staging by 18 F-FDG PET/CT scan in non-small cell lung cancer: Comparison of TB and non-TB endemic regions

UNLABELLED Lymph node staging in non-small cell lung cancer (NSCLC) is challenging and important for deciding treatment policy. The role of PET/CT scans in lymph node staging of NSCLC remains controversial when comparing TB and non-TB endemic regions. This study systematically reviews the literature regarding the diagnostic performance of PET/CT in lymph node staging of patients with NSCLC, and determines its pooled sensitivity and specificity. METHODS The databases of PubMed, Medline, and Cochrane library were searched for relevant studies. Two reviewers independently assessed the methodological quality of each study. A meta-analysis of the reported sensitivity and specificity of each study was performed. RESULTS Seven of 86 studies were included. These studies had moderate to good methodological quality. Pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio for patient-based analyses (five studies) were 66%, 92.7%, 5.86%, and 0.41%, respectively, and those for lesion-based analyses (six studies) were 59.4%, 96.5%, 9.37%, and 0.31%, respectively. Subanalysis of endemic regions of tuberculosis (TB) showed that these regions had lower sensitivity and similar specificity to non-TB endemic regions. CONCLUSION PET/CT showed high specificity in the lymph node staging of NSCLC and lower sensitivity in TB endemic regions.

Incident asthma and Mycoplasma pneumoniae: A nationwide cohort study.

BACKGROUND Previous studies investigating the relationship between Mycoplasma pneumoniae and incident asthma in the general population have been inconclusive. OBJECTIVE We conducted a nationwide cohort study to clarify this relationship. METHODS Using the National Health Insurance Research Database of Taiwan, we identified 1591 patients with M pneumoniae infection (International Classification of Diseases, Ninth Revision, Clinical Modification code 4830) given diagnoses between 2000 and 2008. We then frequency matched 6364 patients without M pneumoniae infection from the general population according to age, sex, and index year. Cox proportional hazards regression analysis was performed to determine the adjusted hazard ratio (aHR) of the occurrence of asthma in the M pneumoniae cohort compared with that in the non-M pneumoniae cohort. RESULTS Regardless of comorbidities and the use of antibiotic or steroid therapies, patients with M pneumonia infection had a higher risk of incident asthma than those without it. The aHR of asthma was 3.35 (95% CI, 2.71-4.15) for the M pneumoniae cohort, with a significantly higher risk when patients were stratified by age, sex, follow-up time, and comorbidities, including allergic rhinitis, atopic dermatitis, or allergic conjunctivitis. Patients with M pneumoniae infection had a higher risk of having early-onset (age, <12 years; aHR, 2.87) and late-onset (age, ≥12 years; aHR, 3.95) asthma. The aHR was also higher within the less than 2-year follow-up in the M pneumoniae cohort (aHR, 4.41; 95% CI, 3.40-5.74) than in the cohort without the infection. CONCLUSION This study found that incident cases of early-onset and late-onset asthma are closely related to M pneumoniae infection, even in nonatopic patients.

Identifying the most infectious lesions in pulmonary tuberculosis by high-resolution multi-detector computed tomography

Objective:This study aimed to determine whether characteristics detected by multi-detector computed tomography (MDCT) were predictive of highly infectious, smear-positive, active pulmonary tuberculosis (PTB).Methods:Among 124 patients with active PTB, 84 had positive (group 1) and 40 had negative (group 2) smear results for acid-fast bacilli. Multiplanar MDCT, axial conventional CT and chest X-ray images were analysed retrospectively for morphology, number, and segmental (lobe) distribution of lesions.Results:By multivariate analysis, consolidation over any segment of the upper, middle, or lingual lobes, cavitations, and clusters of nodules were associated with group 1, while centrilobular nodules were predictive of group 2. Using five independent variables associated with risk in group 1, a prediction model was created to distinguish between group 1 and group 2. ROC curve analysis showed an area under the curve of 0.951 ± 0.021 for this prediction model. With the ideal cutoff point score of 1, the sensitivity, specificity, and positive predictive values were 84.5%, 97.5%, and 98.0%, respectively.Conclusions:A model to predict smear-positive active PTB on the basis of findings from MDCT may be a useful tool for clinical decisions about isolating patients pending sputum smear results.