Asthma

Web site for latest treatment guidelines:
http://www.nhlbi.nih.gov/guidelines/asthma/asthgdln.pdf

Inhaled steroids vs. bronchodilators
Nelson HS, Weiss ST, Bleecker ER, et al, SMART Study Group. The salmeterol multicenter asthma research trial. Chest 2006; 130:928. This randomized, double-blinded, placebo-controlled, observational study (N= 26,355) showed a small, but statistically significant increase in respiratory-related and asthma-related deaths for the population receiving salmeterol. It is uncertain whether poor outcomes were due to physiologic treatment effects, genetic factors, or patient behaviors. http://www.ncbi.nlm.nih.gov/pubmed/16424409?ordinalpos=9&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum
 
Haahtala T, Jarvinen M, Kava T, et al. Comparison of a beta-agonist, terbutaline, with an inhaled corticosteroid, budesonide, in newly detected asthma. New Engl J Med 1991; 325:388-92. This randomized, blinded comparison of the above two drugs was important in establishing inhaled corticosteroids as the first line treatment for asthma. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=2062329

Lazarus SC, Boushey HA, Fahy JV et al. Long-acting beta2-agonist monotherapy vs. continued therapy with inhaled corticosteroids in patients with persistent asthma: a RCT. JAMA 2001;285:2583-93.  Switching from low dose ICS to long-acting beta2-agonist in patients with well-controlled, persistent asthma increased the risk of treatment failure and asthma exacerbations.  http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11368732

As needed use of inhaled steroids in mild asthma
Boushey HA, Sorkness CA, King TS, et al. Daily versus as-needed corticosteroids for mild persistent asthma. N Engl J Med 2005; 352:1519-28. A year-long RCT of 225 adults with mild persistent asthma compared prn corticosteroids based upon symptom-based action plan vs. daily treatment with ICS vs. daily leukotriene inhibitor and found no difference in morning peak expiratory flow and the rate of asthma exacerbations despite the prn corticosteroid group using an average of only 0.5 week of steroid per year. The ICS group had superior asthma control scores and lower markers of airway inflammation.  Some attribute this relatively modest benefit of regular ICS use to the lower exacerbation rate in this study compared to its predecessors, which speaks to the challenge of identifying mild persistent asthmatics. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15829533&query_hl=6&itool=pubmed_docsum

Papi A, Canonica GW, Maestrelli P, et al. Symptomatic use of beclomethasone plus albuterol and regular use of beclomethasone did not differ for control of mild asthma. N Engl J Med 2007; 356:2040-52. RCT of 466 patients of 6 months duration found PRN use of a single inhaler combination of beclomethasone and albuterol resulted in better peak flows and fewer exacerbations compared to PRN use of albuterol alone, as well as comparable peak flows, exacerbation rate, lung function, and symptoms to regular twice daily use of beclomethasone. The PRN beclomethasone group on average used < 125 mcg/day compared to 500 mcg/day in the regular twice daily groups.  http://www.ncbi.nlm.nih.gov/pubmed/17507703?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus

Inhaled steroid vs. leukotrience receptor antagonists
Laviolette M, Malmstrom K, Lu S, et al. Montelukast added to inhaled beclomethasone in treatment of asthma. Am J Respir Crit Care Med 1999;160:1862-68. This randomized, double-blinded study supports the addition of a leukotriene inhibitor for asthmatics with inadequate symptom control with inhaled corticosteroid alone. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10588598
Malmstrom K, Rodriguez-Gomez G, Guerra J, et al. Oral montelukast, inhaled beclomethasone, and placebo for chronic asthma. A randomized controlled trial. Ann Intern Med 1999;130:487-95. Both inhaled steroid and a leukotriene inhibitor were better than placebo. Beclomethasone was significantly better than montelukast in reducing exacerbations and symptoms. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10075616

Combination therapies
O’Byrne PM, Bisgaard H, Godard PP, et al. Budesonide/formoterol combination therapy as both maintenance and reliever medication in asthma.  Am J Respir Crit Care Med  2005: 171;129-36.  This study included 2,760 asthmatics with a history of at least one exacerbation in the previous year and regular need for rescue bronchodilators despite baseline use of, on average, moderate doses of inhaled corticosteroid.  Patients randomized to budesonide/formoterol (80/4.5) bid and prn had prolonged time to exacerbations requiring medical intervention compared to combination therapy with terbutaline prn or higher dose steroid (budesonide 320 bid) plus terbutaline prn.  Subsequent RCTs have also shown favorable outcomes with this approach. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=15502112&query_hl=9&itool=pubmed_DocSum

Bateman ED, Boushey HA, Bousquet J, et al. GOAL Investigators Group. Can guideline-defined asthma control be achieved? The Gaining Optimal Asthma Control study. Am J Respir Crit Care Med. 2004;170:836-44.  This is a 1-year, randomized, stratified, double-blind, parallel-group study (n=3,421) of patients with uncontrolled asthma comparing the addition of LABA vs escalating steroidin achieving two rigorous, composite, guideline-based measures of control: totally and well-controlled asthma.  Control was achieved more rapidly and at a lower corticosteroid dose with salmeterol/fluticasone versus fluticasone alone.
http://www.ncbi.nlm.nih.gov/pubmed/15256389?ordinalpos=5&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum

Anti-IgE therapy
Busse WW.  Anti-immunoglobulin E (omalizumab) therapy in allergic asthma.  Am J Respir Crit Care Med 2001;164(8Pt2):S12-7. Review summarizes several large RCTs studying the role of anti-IgE antibody in allergic asthma.  The use of anti-IgE is associated with decreased frequency of exacerbations, reductions in corticosteroid dose, and improved quality of life in symptomatic patients with moderate to severe allergic asthma.   http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11704612

Wu AC, Paltiel AD, Kuntz KM, et al.  Cost-effectiveness of omalizumab in adults with severe asthma: results from the Asthma Policy Model.  J Allergy Clin Immunol. 2007; 120:1146-52.  This article uses merged published data on clinical and economic outcomes (including acute event incidence, frequency/severity of hospitalizations, and health-related quality of life) to project 10-year costs, quality-adjusted life years (QALYs), and cost-effectiveness of treatment with omalizumab in addition to inhaled corticosteroids.  Using these methods, it concludes omalizumab is not cost-effective for most patients with severe asthma.
http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&otool=umnbmlib&term=Cost-effectiveness%20of%20omalizumab%20in%20adults%20with%20severe%20asthma%3A%20results%20from%20the%20Asthma%20Policy%20Model

Bronchial Thermoplasty
Cox G, Thomson NC, Rubin AS, et al. Asthma control during the year after bronchial thermoplasty. N Engl J Med. 2007;356:1327-37.   12-month randomized study of 112 subjects with moderate to severe persistent asthma found that, compared to controls, the BT group had significantly greater improvements  in morning peak expiratory flow, quality of life scores, percentage of symptom-free days, and symptom scores, despite requiring fewer puffs of rescue medication. Adverse events immediately after treatment were more common in the BT group but were similar to controls from 6 weeks to 12 months after treatment.
http://www.ncbi.nlm.nih.gov/pubmed/17392302?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum 

Exercise-induced
Edelman JM, Turpin JA, Bronsky EA, et al. Oral montelukast compared with inhaled salmeterol to prevent exercise- induced bronchoconstriction. A randomized, double-blind trial. Ann Intern Med 2000;132:97-104. Study found leukotriene blockade has equal efficacy to a beta-agonist for the prevention of EIB and that daily administration is not associated with a reduction in efficacy that may be seen with daily dosing of long-acting beta agonists. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10644288

Airway remodeling
Lange P, Parner J, Vestbo J, Schnohr P, Jensen G. A 15-year follow-up study of ventilatory function in adults with asthma. N Engl J Med 1998;339:1194-200. Noteworthy for being one of the studies showing that a portion of patients with asthma go on to develop fixed airway obstruction. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9780339