April 2012

Section Bulletin Online Now

The Spring edition of our Section Bulletin is ONLINE NOW, so click over to read a “Notes” column by Lisa Becker that introduces an article addressing the controversial issue of whether or not to wait a minute between MDI puffs. A representative of the European Respiratory Society closes out the issue with an overview of his organization and its Assembly 9 for allied respiratory professionals.

Lung Function Development With and Without BPD

Researchers publishing ahead of print in BMC Pediatrics on Mar. 23 find longitudinal lung function testing of preterm infants over time may help identify infants with bronchopulmonary dysplasia (BPD) who exhibit an incomplete recovery of respiratory function. They reached that conclusion after analyzing data on 29 very low birth weigh (VLBW) infants who developed BDP and 26 VLBW infants who did not. Mean gestational age for the two groups was 26 vs. 29 weeks, respectively; mean birth weight was 815 grams vs. 1125 grams; and mean need for mechanical ventilation for seven days or longer was 55% vs. 8%. Lung function tests were performed at 50, 70, and 100 weeks postmenstrual age. Respiratory rate, respiratory or airway resistance, FRC as determined by body plethysmography, maximal expiratory flow at the FRC, and blood gas levels were similar between the two groups. Tidal volume, minute ventilation, respiratory compliance, and FRC determined by SF6 multiple breath washout were lower in the BPD infants, although they lost statistical significance when the results were adjusted to take the infants’ overall lower body weights into account. READ ABSTRACT

Airway Hyperresponsiveness to Mannitol May Predict Response to Inhaled Corticosteroids in Mild to Moderate COPD

New research out of Switzerland finds airway hyperresponsiveness to mannitol may be useful in determining which patients with mild to moderate COPD will benefit from treatment with inhaled corticosteroids. The randomized, double-blind study was conducted among 68 patients, 38 of whom had airway hyperresponsiveness to mannitol. Those patients were then assigned to either budesonide or placebo, along with tiotropium, for three months. Among the patients with initial airway hyperresponsiveness to mannitol, treatment with budesonide resulted in improved quality of life when compared to placebo. A subsequent reduction in airway responsiveness to mannitol was seen with the active treatment as well. The authors conclude, “In subjects with mild to moderate COPD and airway hyperresponsiveness to mannitol, quality of life and airway responsiveness improved after treatment with inhaled corticosteroids added to long-acting bronchodilator therapy.” The study was published ahead of print in CHEST on Mar. 29. READ ABSTRACT

LLN FEV1/FVC vs. Fixed FEV1/FVC Cutpoints

Using the lower limit of normal (LLN) FEV1/FVC cutpoint to determine whether respiratory symptomatic subjects over the age of 40 are classified as obstructive or non-obstructive can predict which people will demonstrate a decline in FEV1. That’s the take home message from researchers who divided a cohort of 3324 patients into four categories based on the presence or absence of obstruction according to the fixed and LLN FEV1/FVE cutpoints. Overall, 918 subjects were determined to be obstructive according to the fixed FEV1/FVC cutpoint. But according to the LLN cutpoint, 389, or 42%, of those patients were non-obstructive. According to both cutpoints, postbronchodilator FEV1 decline was 21 ml/year in the non-obstructive patients who smoked. It was 21 ml/year in obstructive smokers according to the fixed but not according to the LLN cutpoint. It was 50 ml/year in the obstructive smokers according to both cutpoints. The authors write, “This study showed that respiratory symptomatic 40+ smokers and non-smokers who show FEV1/FVC values below the fixed 0.70 cutpoint but above their age/gender specific LLN value did not show accelerated FEV1 decline, in contrast with those showing FEV1/FVC values below their LLN cutpoint.” The study was published ahead of print by BMC Pulmonary Medicine on Mar. 22. READ ABSTRACT

Obesity, Not Air Flow Obstruction, May Cause Respiratory Problems in the Obese

University of California, San Francisco investigators recently looked at the relationship between obesity and airflow obstruction (AO) and respiratory symptoms in 371 adults without a previous diagnosis of COPD. Among the findings:

• 69 (19%) had AO.
• In multivariate analysis, smoking was positively associated with AO while obesity was negatively associated with AO.
• Obesity was associated with increased odds of reporting dyspnea on exertion, productive cough, and decrements in six minute walk test distance and Short Performance Physical Battery scores; none of these outcomes was associated with AO.

The authors conclude, “Although AO and obesity are both common among adults without an established COPD diagnosis, obesity (but not AO) is linked to a higher risk of reporting dyspnea on exertion, productive cough, and poorer functional capacity.” The study was published ahead of print by the Primary Care Respiratory Journal on Mar. 28. READ ABSTRACT