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The safety of regular long-acting beta(2)-agonists in children with asthma: an overview of Cochrane reviews.

Paediatr Respir Rev. 2012 Nov 21;

Authors: Cates C

PMID: 23200881 [PubMed - as supplied by publisher]

Airway epithelium is a predominant source of endogenous airway GABA and contributes to relaxation of airway smooth muscle tone.

Am J Physiol Lung Cell Mol Physiol. 2012 Nov 30;

Authors: Gallos G, Townsend EA, Yim P, Virag L, Zhang Y, Xu D, Bacchetta M, Emala CW

Abstract
COPD and asthma are characterized by hyper-reactive airway responses that predispose patients to episodes of acute airway constriction. Recent studies suggest a complex paradigm of GABAergic signaling in airways that involves GABA-mediated relaxation of airway smooth muscle. However, the cellular source of airway GABA and mechanisms regulating its release remain unknown. We questioned whether epithelium is a major source of GABA in the airway and if the absence of epithelium-derived GABA contributes to greater airway smooth muscle force. Messenger RNA encoding glutamic acid decarboxylase (GAD) 65/67 was quantitatively measured in human airway epithelium and smooth muscle. High pressure liquid chromatography quantified GABA levels in guinea pig tracheal ring segments under basal or stimulated conditions with or without epithelium. The role of endogenous GABA in the maintenance of an acetylcholine contraction in human airway and guinea pig airway smooth muscle was assessed in organ baths. A 37.5-fold greater amount of mRNA encoding GAD 67 was detected in human epithelium versus airway smooth muscle cells. HPLC confirmed that guinea pig airways with intact epithelium have a higher constitutive elution of GABA under basal or KCl-depolarized conditions compared to epithelium-denuded airway rings. Inhibition of GABA transporters significantly suppressed KCl-mediated release of GABA from epithelium intact airways, but tetrodotoxin was without effect. The presence of intact epithelium had a significant GABAergic-mediated pro-relaxant effect on the maintenance of contractile tone. Airway epithelium is a predominant cellular source of endogenous GABA in the airway and contributes significant pro-relaxant GABA effects on airway smooth muscle force.

PMID: 23204068 [PubMed - as supplied by publisher]

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Levalbuterol versus albuterol for acute asthma: a systematic review and meta-analysis.

Pulm Pharmacol Ther. 2012 Nov 30;

Authors: Jat KR, Khairwa A

Abstract
BACKGROUND: Conventional albuterol is a racemic mixture of (S)-albuterol and (R)-albuterol (levalbuterol). Levalbuterol is therapeutically active component of albuterol whereas (S)-albuterol is considered inert with some unwanted effects. OBJECTIVES: to evaluate efficacy and safety of levalbuterol versus albuterol in acute asthma. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Pubmed and Cochrane databases. Trial eligibility criteria, participants, and interventions: Randomized control trials comparing levalbuterol versus albuterol for acute asthma in all age groups. Data extraction and result synthesis: Two authors extracted data independently. Meta-analyses were performed using Review Manager Software. RESULTS: Seven trials including a total of 1625 participants fulfilled the eligibility criteria. Respiratory rate, oxygen saturation, and percentage change in FEV1 and clinical asthma score were not significantly different between the groups with mean difference (95% CI) of 0·35 (-0·81, 1·51), -0·29 (-0·68, 0·10), -28·3 (-59·95, 3·33) and -1·01 (-5·30, 3·28) respectively. There were no significant differences in side effects between groups. LIMITATIONS: Data were not available for two probable eligible trials. A few assumptions and some calculated values were used for meta-analysis. CONCLUSIONS: Levalbuterol was not superior to albuterol regarding efficacy and safety in subjects with acute asthma. We suggest that levalbuterol should not be used over albuterol for acute asthma.

PMID: 23207739 [PubMed - as supplied by publisher]

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Readability, Suitability, and Characteristics of Asthma Action Plans: Examination of Factors That May Impair Understanding.

Pediatrics. 2012 Dec 3;

Authors: Yin HS, Gupta RS, Tomopoulos S, Wolf MS, Mendelsohn AL, Antler L, Sanchez DC, Lau CH, Dreyer BP

Abstract
OBJECTIVE:Recognition of the complexity of asthma management has led to the development of asthma treatment guidelines that include the recommendation that all pediatric asthma patients receive a written asthma action plan. We assessed the readability, suitability, and characteristics of asthma action plans, elements that contribute to the effectiveness of action plan use, particularly for those with limited literacy.METHODS:This was a descriptive study of 30 asthma action plans (27 state Department of Health (DOH)-endorsed, 3 national action plans endorsed by 6 states). Outcome measures: (1) readability (as assessed by Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, Simple Measure of Gobbledygook, Forcast), (2) suitability (Suitability Assessment of Materials [SAM], adequate: ≥0.4; unsuitable: <0.4), (3) action plan characteristics (peak flow vs symptom-based, symptoms, recommended actions).RESULTS:Mean (SD) overall readability grade level was 7.2 (1.1) (range = 5.7-9.8); 70.0% were sixth-grade level or higher. Mean (SD) suitability score was 0.74 (0.14). Overall, all action plans were found to be adequate, although 40.0% had an unsuitable score in at least 1 factor. The highest percent of unsuitable scores were found in the categories of layout/typography (30.0%), learning stimulation/motivation (26.7%), and graphics (13.3%). There were no statistically significant differences between the average grade level or SAM score of state DOH developed action plans and those from or adapted from national organizations. Plans varied with respect to terms used, symptoms included, and recommended actions.CONCLUSIONS:Specific improvements in asthma action plans could maximize patient and parent understanding of appropriate asthma management and could particularly benefit individuals with limited literacy skills.

PMID: 23209106 [PubMed - as supplied by publisher]