Sravanya Gavini

Idiopathic pulmonary fibrosis is associated with increased impedance measures of reflux compared to non‐fibrotic disease among pre‐lung transplant patients

Gastroesophageal reflux (GER) has been associated with idiopathic pulmonary fibrosis (IPF), although the mechanism remains unclear. Gastroesophageal reflux/microaspiration may lead to lung fibrosis, while increased pulmonary workload may also worsen GER. Comparing the GER profile of IPF patients to chronic obstructive pulmonary disease (COPD) patients with similar lung function may help delineate the role of GER in IPF pathogenesis.

Caesarean section to prevent transmission of hepatitis B: A meta-analysis

BACKGROUND Vertical transmission of hepatitis B virus (HBV) occurs in up to 10% to 20% of births. OBJECTIVE To assess whether Caesarean section, compared with vaginal delivery, prevents HBV transmission. METHODS A systematic review and meta-analysis was conducted. Two investigators independently searched PubMed, EMBASE and other databases for relevant studies published between 1988 and 2013. A manual search of relevant topics and major conferences for abstracts was also conducted. Randomized trials, cohort and case-control studies assessing the effect of delivery mode on vertical transmission of HBV were included. Studies assessing antiviral therapy and patients with coinfection were excluded. The primary outcome was HBV transmission rates according to delivery method. RESULTS Of the 430 studies identified, 10 were included. Caesarean section decreased the odds of HBV transmission by 38% compared with vaginal delivery (OR 0.62 [95% CI 0.40 to 0.98]; P=0.04) based on a random-effects model. Significant heterogeneity among studies was found (I²=63%; P=0.003), which was largely explained by variation in hepatitis B immune globulin (HBIG) administration. Meta-regression showed a significant linear association between the percentage of infants receiving HBIG per study and the log OR (P=0.005), with the least benefit observed in studies with 100% HBIG administration. Subgroup analysis of hepatitis B e-antigen-positive women who underwent Caesarean section did not show a significant reduction in vertical transmission. DISCUSSION Caesarean section may protect against HBV transmission; however, convincing benefit could not be demonstrated due to significant study heterogeneity from variable HBIG administration, highlighting the importance of HBIG in HBV prevention. CONCLUSION More high-quality studies are needed before any recommendations can be made.

Lung disease severity in idiopathic pulmonary fibrosis is more strongly associated with impedance measures of bolus reflux than pH parameters of acid reflux alone

Gastroesophageal reflux (GER) has been associated with idiopathic pulmonary fibrosis (IPF). Pathogenesis may be related to chronic micro‐aspiration. We aimed to assess objective measures of GER on multichannel intraluminal impedance and pH study (MII‐pH) and their relationship with pulmonary function testing (PFT) results, and to compare the performance of pH/acid reflux parameters vs corresponding MII/bolus parameters in predicting pulmonary dysfunction in IPF.

Abnormal Bolus Reflux Is Associated With Poor Pulmonary Outcome in Patients With Idiopathic Pulmonary Fibrosis

Background/Aims Gastroesophageal reflux (GER) is postulated to play a role in idiopathic pulmonary fibrosis (IPF). However, the value of objective GER measures in predicting IPF disease progression is unclear. We aim to evaluate the association between objective GER measures on multichannel intraluminal impedance and pH (MII-pH) testing and development of poor pulmonary outcomes within 1 year in pre-lung transplant IPF patients. Methods This was a retrospective cohort study of adults with IPF who underwent pre-lung transplant evaluation with MII-pH off proton pump inhibitors (PPI) at a tertiary care center from June 2008 to November 2015. Patients were followed for 1 year from time of MII-pH for poor pulmonary outcomes, defined by hospitalization for respiratory exacerbation or death. Univariate, multivariate and time-to-event analyses were performed to assess associations between baseline GER parameters on MII-pH and poor outcomes. Results Eighty-four subjects (mean age 61.1 years, 64.3% male) were included. Subjects with increased bolus exposure time (BET) had a higher incidence of 1-year poor pulmonary outcome vs normal BET (45.7% vs 15.2%, P = 0.006). Increased BET remained an independent predictor of poor outcome after controlling for age, gender, body mass index, smoking, lung disease severity, and PPI use (OR, 4.18; P = 0.030). Increased BET was also predictive of decreased time to poor pulmonary outcome (hazard ratio [HR], 4.88; P = 0.007). Subgroup analyses showed that increased BET remained independently associated with time to pulmonary hospitalization (HR, 4.00; P = 0.020), with a trend for 1-year mortality (HR, 2.19; P = 0.380). Conclusion Increased BET on MII-pH is an independent predictor of poor pulmonary outcome over 1 year in IPF patients.

241 Increased Reflux Severity on Impedance Predicts One-Year Pulmonary Function Decline in Pre-Lung Transplant Patients With Idiopathic Pulmonary Fibrosis

Background: Gastroesophageal reflux (GER) has been associated with pulmonary disease in pre-lung transplant patients, especially idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD). The mechanism of these associations remains controversial. Microaspiration of refluxate may lead to inflammatory changes and pulmonary fibrosis or airway disease. Worsening pulmonary function may also increase trans-diaphragmatic pressure gradient, magnifying GER. The association between GER and decline in lung function in these patients has not yet been demonstrated. Evaluating the relationship between objective reflux parameters and change in pulmonary function may help clarify pathophysiology and identify targets for treatment. Aim: To investigate the association between objective measures of reflux on multichannel intraluminal impedance and pH study (MII-pH) and change in pulmonary function testing (PFT) parameters over one year, in pre-lung transplant patients with IPF or COPD. Methods: This was a retrospective cohort study of adults with IPF or COPD who underwent pretransplant evaluation with MII-pH, off acid suppression, at a tertiary care center from 6/2010-14. Patients with fundoplication prior to MII-pH were excluded. PFT was performed within 1 month of MII-pH and at 12-month follow-up. Association between baseline reflux measures and change in PFT parameters over one year was evaluated using Students t-test for continuous variables and Fishers exact test for binary variables. Results: 57 subjects (mean age=60 yrs, 42% female, 37 IPF vs 20 COPD) met criteria for inclusion. Among IPF patients, abnormal bolus reflux on impedance was associated with a significant decline in forced expiratory volume in 1 second (FEV1) in 1 year (-0.048 L/sec vs +0.24 L/sec, p=0.041), as was increased acid exposure time (-0.195 L/sec vs +0.144 L/sec, p=0.05). Trends toward more severe decline in forced vital capacity (FVC) in 1year for both abnormal bolus reflux (-0.085 L/sec vs +0.25 L/sec, p=0.09) and increased acid exposure time (-0.28 L/sec vs +0.147 L/sec, p=0.10) were also observed. Among COPD patients, trends toward more severe decline in FEV1 in 1 year was noted for increased acid exposure time (-0.27 L/sec vs -0.035 L/sec, p=0.087). No other significant associations between change in PFT and abnormal MII-pH parameters were found (Table 1). Conclusion: Abnormal GER as measured on MII-pH predicts more severe decline in lung function in 1 year on PFT among pre-lung transplant patients with IPF. A similar association between GER and lung function decline was not found in COPD patients. GER may play a more significant role in the pathogenesis of IPF than COPD. Future long-term studies are needed to further characterize the effect of GER on severity and prognosis of pulmonary disorders. Association between measures of reflux severity and worse pulmonary function (FEV1) after 1 year in patients with IPF.