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Ronina A Covar

Publications and source records attributed to Ronina A Covar.

12 recordsLinked to original sources
PubMed2006

Long-term comparison of 3 controller regimens for mild-moderate persistent childhood asthma: the Pediatric Asthma Controller Trial.

BACKGROUND: More evidence is needed on which to base recommendations for treatment of mild-moderate persistent asthma in school-aged children. OBJECTIVE: The Pediatric Asthma Controller Trial (PACT) compared the effectiveness of 3 regimens in achieving asthma control. METHODS: A total of 285 children (ages 6-14 years) with mild-moderate persistent asthma on the basis of symptoms, and with FEV(1) >or= 80% predicted and methacholine FEV(1) PC(20) or= 80% predicted, confirming current guideline recommendations.

Acetates↗
PubMed2006

Effect of montelukast on peripheral airflow obstruction in children with asthma.

BACKGROUND: Montelukast is a widely used controller agent in childhood asthma. It is modestly effective in reducing symptoms, decreasing the need for rescue albuterol, and improving forced expiratory volume in 1 second (FEV1). OBJECTIVE: To determine whether montelukast therapy improves peripheral airway obstruction as measured by lung volumes, air trapping, airway resistance (Raw), and specific conductance (Sgaw). METHODS: Twenty-one children aged 9 to 18 years with mild-to-moderate asthma were randomized into a double-blind, placebo-controlled study to receive montelukast (5 or 10 mg) or matching placebo daily for 8 weeks. Symptoms and albuterol use were recorded twice daily, and exhaled nitric oxide measurement, forced oscillometry, spirometry, and body box plethysmography (before and after beta-agonist use) were performed at randomization and at 2, 4, 6, and 8 weeks. Circulating eosinophil counts and serum eosinophil cationic protein (ECP) levels were obtained at randomization and at 8 weeks. RESULTS: Montelukast-treated patients had lower residual volume (P = .05), residual volume-total lung capacity ratio (P = .04), Raw (P = .02), Sgaw (P = .03), and serum ECP levels (P = .02) at 8 weeks compared with those treated with placebo. There was a trend toward reduced daytime and nighttime albuterol use, although the difference did not reach statistical significance. There were no significant differences in FEV1, FEV1-forced vital capacity ratio, exhaled nitric oxide levels, or daytime and nighttime symptom scores between the 2 groups. CONCLUSIONS: Montelukast therapy was associated with less air trapping, hyperinflation, and Raw and better Sgaw compared with placebo. Lower serum ECP levels, a surrogate measure of airway inflammation, were associated with improvements in lung function.

Acetates↗
PubMed2005

Quantitative computed tomography detects peripheral airway disease in asthmatic children.

The aim of this study was to compare air-trapping as quantified by high-resolution computed tomography (HRCT) of the chest with measures of lung function and airway inflammation in children with mild to moderate asthma. Plethysmography indices, respiratory resistance, and reactance before and after bronchodilator with impulse oscillation (IOS), exhaled nitric oxide (eNO), total eosinophil count (TEC), and serum eosinophil cationic protein (ECP) levels were measured in 21 subjects. A single-cut HRCT image at end-expiration was obtained. Air-trapping was quantified and expressed in terms of the pixel index (PI) by determining the percentage of pixels in lung fields below -856 and -910 Hounsfeld units (HU). Pairwise linear correlations between PI and other parameters were evaluated. Subjects had only mild airflow limitation based on prebronchodilator forced expiratory volume in 1 sec (FEV(1)), but were hyperinflated and had air-trapping based on elevated total lung capacity (TLC) and residual volume (RV)/TLC ratio, respectively. The PI at -856 HU was positively correlated with % predicted TLC, total gas volume (TGV), and ECP level, and was inversely correlated with FEV(1)/forced vital capacity (FVC) and % predicted forced expiratory flow between 25-75% FVC (FEF(25-75)). The PI at -910 HU correlated similarly with these variables, and also correlated positively with IOS bronchodilator reversibility. This data suggest that quantitative HRCT may be a useful tool in the evaluation of peripheral airflow obstruction in children with asthma.

Adolescent↗
PubMed2005

Medications as asthma triggers.

Certain medications can generate asthma symptoms, with the potential to cause considerable morbidity. This article focuses on the common drugs that have the potential to cause distinct respiratory reactions in asthmatics: aspirin and other nonsteroidal anti-inflammatory drugs, beta-blockers, and angiotensin-converting enzyme inhibitors. The means by which these medications can trigger asthma vary in terms of acuity of onset, severity, and the mechanisms involved. The general and most practical approach is avoidance and cautious use of these drugs in asthmatics. However, these classes of medications can exert a major role in the management of common and serious diseases. Fortunately, controller therapy for asthma and alternative or more selective medications for the treatment of these conditions are now available.

Adrenergic beta-Antagonists↗
PubMed2005

Progression of asthma in childhood.

In general, asthma runs a variable course. However, there are children with asthma who are at risk for progressive disease that can lead to failure to attain peak lung growth and eventually can result in clinical and functional impairment. We present a case of a 14-year-old girl who has demonstrated a deterioration in lung function at least in the past 6 years. This has been associated with increasing medication requirements, including chronic oral corticosteroid and a steroid-sparing medication, the presence of comorbidities, and the occurrence of frequent exacerbations. The patient has evidence of airway inflammation and remodeling based on biomarkers and biopsy findings. It remains a challenge to determine patients at risk for irreversible airflow obstruction, presumably a result of airway remodeling. Histopathologic studies from biopsy samples provide the best evidence for this. However, bronchoscopy and biopsy require technical expertise and cannot be routinely used. Clinically, once a patient increases medication requirements, this should serve as a marker of disease progression. Biomarkers of airway inflammation such as exhaled nitric oxide, exhaled breath condensates, and induced sputum analysis may have the potential to monitor disease progression. Additional efforts are necessary to understand the mechanisms involved in this phenomenon and to discover specific modalities of treatment to target the structural changes of airway remodeling.

Adolescent↗
PubMed2005

Racial differences in T-lymphocyte response to glucocorticoids.

BACKGROUND: Asthma morbidity and mortality is increased in blacks. OBJECTIVE: The primary objective of this cross-sectional study was to determine if blacks, asthmatic or nonasthmatic, displayed diminished T-lymphocyte response to glucocorticoids in vitro compared to their white counterparts. If differences were noted, this would suggest a racial predisposition to decreased glucocorticoid responsiveness among blacks. METHODS: Asthmatic (n = 395, 27% blacks) and control (n = 202, 52% blacks) subjects recruited from National Jewish Medical and Research Center and from the surrounding community participated in the study. In vitro glucocorticoid responsiveness was determined by assessing the log-transformed concentration of dexamethasone required to suppress phytohemagglutinin-induced T-lymphocyte proliferation by 50% (log(10) IC(50)). Asthma medication history, atopic status, and spirometric lung function measures corrected for race were collected. RESULTS: Black and white asthmatic subjects had similar FEV(1) percentage of predicted values and inhaled and oral glucocorticoid requirements. Black asthmatic subjects displayed significantly diminished glucocorticoid responsiveness compared to white asthmatic subjects, as follows: median (first, third quartile) log(10) IC(50) values of 1.00 nmol (0.48, 1.83) vs 0.78 nmol (0.29, 1.45) [p = 0.028]. Similar results were found between black and white control subjects, as follows: median, 1.26 nmol (0.70, 2.14) vs 0.95 nmol (0.55, 1.48) [p = 0.01]. Age, race, and basal T-lymphocyte activity were significantly positively correlated to the log(10) IC(50) values. CONCLUSION: Our observation that black asthmatic subjects and non-asthmatic control subjects require greater concentrations of glucocorticoid in vitro to suppress T-lymphocyte activation suggests that blacks have a racial predisposition to diminished glucocorticoid responsiveness, which may contribute to their heightened asthma morbidity.

Adolescent↗
PubMed2004

Progression of asthma measured by lung function in the childhood asthma management program.

From the Childhood Asthma Management Program cohort, which was randomly assigned to receive budesonide, nedocromil, or placebo for 4-6 years, we determined the prevalence of and factors associated with at least 1% per year loss in postbronchodilator FEV(1)% predicted. Participants who had a significant reduction in postbronchodilator FEV(1)% predicted (SRP), comprised 25.7% of the cohort (n = 990). Using logistic regression, predictors of SRP at baseline were younger age (p = 0.0005), male sex (p < 0.0001), clinic (p = 0.02), and higher postbronchodilator FEV(1)% predicted (p = 0.02). Examination of the SRPs indicated that the effect of baseline lung function was such that the higher the lung function, the less steep the reduction in postbronchodilator FEV(1)% predicted (p < 0.0001). A similar proportion of SRPs was found in each treatment group. Among the SRPs, the rate of reduction in postbronchodilator FEV(1)% predicted was similar in all treatment groups. At a single site where biomarker assessment was performed, SRPs also had more prominent eosinophilic inflammation during the washout period. The course and mechanisms of lung function reduction or slow lung growth velocity in children with asthma must be defined.

Administration, Inhalation↗
PubMed2004

Safety and application of induced sputum analysis in childhood asthma.

BACKGROUND: The value of sputum induction in pediatric asthma lies in its potential to directly and noninvasively assess airway inflammation in children, because bronchoscopy and biopsy carry some risk. The Childhood Asthma Management Program (CAMP) study was designed to evaluate the long-term effects of budesonide and nedocromil compared with placebo in children with mild to moderate asthma across 8 centers. OBJECTIVE: At the Denver CAMP site, we sought to evaluate the safety of sputum induction, to determine differences in airway inflammation between treatment groups by using induced sputum analysis, and to examine correlations between other biomarkers and sputum eosinophils. METHODS: Sputum induction was performed, and exhaled nitric oxide, circulating eosinophil counts, and serum eosinophil cationic protein were obtained at treatment discontinuation and after washout. Spirometry and a methacholine challenge were also performed according to the CAMP protocol. RESULTS: Ninety of 117 children provided an adequate sputum sample for analysis. In 9 subjects (3 nedocromil and 6 placebo), sputum induction resulted in bronchospasm. These subjects had greater disease severity, as measured by a lower median prebronchodilator FEV 1 percentage predicted (85.0% vs 96.0%; P =.024) and FEV 1 /FVC ratio (70.0% vs 79.0%; P =.0008); greater bronchodilator reversibility (16.5% vs 6.8%; P =.004); higher serum IgE (1390.0 vs 495.0 ng/mL; P =.017) and circulating eosinophil count (757.0 vs 282.0/mm 3; P =.04); greater use of prednisone (1.9 vs 0.9 courses per 100 person-years; P =.05); and greater supplemental inhaled steroid doses (85.3 vs 0 mg; P =.016). At treatment discontinuation, budesonide-treated patients had a lower median (1st, 3rd quartile) sputum percentage eosinophil (SPEos) (0.2% [0%, 1.2%] vs 0.8% [0.2%, 4.6%]; P =.03) compared with those treated with placebo; no significant difference was noted between nedocromil- and placebo-treated patients. Higher SPEos at the time of treatment discontinuation was associated with asthma worsening that required rescue prednisone (n = 23) during the washout period compared with patients who remained stable (3.6% [0.4%, 6.4%] vs 0.6% [0.2%, 3.2%] SPEos; P =.023). Finally, greater SPEos was associated with atopy, higher bronchodilator reversibility, lower FEV 1 /FVC ratio, higher exhaled nitric oxide levels, circulating eosinophils, sputum and serum eosinophil cationic protein, more prednisone courses during the treatment period, and greater asthma severity. CONCLUSIONS: Sputum induction is a relatively noninvasive and safe procedure that can provide information on eosinophilic inflammation and treatment response and is also associated with several measures of asthma control. However, this procedure still remains a research tool in asthma because of its requirements for technical expertise.

Adolescent↗
PubMed2003

Weighing the risks of treatment versus nontreatment in pediatric asthma.

During the past dozen years, great strides have been made in the understanding of asthma. In addition, an excellent choice of effective and safe medications has become available for use in both the acute and chronic manifestations of this disease. Unfortunately, asthma continues to affect society adversely in terms of cost and morbidity. Following the NHLBI guidelines for the management of persistent asthma could substantially reduce the health care expenditures associated with asthma and, more importantly could significantly reduce asthma exacerbations, emergent care visits, hospitalizations, and even asthma deaths. All who care for children with asthma must continue to relay the message that asthma is a chronic condition that is best treated with controller agents. Inhaled glucocorticoids are considered first-line agents for all patients with persistent asthma. They have been shown to improve asthma control, improve lung function, and reduce morbidity and mortality. Whether the leukotriene-modifying agents will be shown to reduce morbidity and mortality significantly remains an important and unanswered question at present. Another important question is whether combination therapy and which combination (inhaled glucocorticoid plus LABA or inhaled glucocorticoid plus leukotriene-modifying agent) will provide even further improvement in asthma control and further reductions in hospitalizations and mortality than seen with the use of inhaled glucocorticoids alone.

Administration, Inhalation↗
PubMed2003

Treating the wheezing infant.

The management of infants and small children with asthma is a challenging task because of the many issues unique to this age group that deserve special consideration. The diagnosis of asthma is limited by inherent difficulties in obtaining objective measures of lung function and airway inflammation. In persistently symptomatic patients, the decision to initiate controller therapy is not as great an issue as it is in infants and young children with recurrent episodic wheeze in whom early intervention may allow a window of opportunity potentially to alter the course of the disease. The reality is that even if atopy has been consistently implicated in the development of persistent asthma, there is not a well-established set of criteria by which patients who are likely to benefit from early intervention controller therapy can be identified. Hence, large prospective studies need to be performed evaluating the impact of early pharmacologic intervention on the natural history of infantile asthma. Many areas needing investigation involve what medications to use, how best to deliver the medications, and how to monitor the response to treatment. Only a few medications have been approved for use in this population. Long-term studies evaluating available drugs such as inhaled glucocorticoids, LABAs, and the leukotriene-modifying agents in young children still need to be performed.

Administration, Inhalation↗
PubMed2003

Relations between exhaled nitric oxide and measures of disease activity among children with mild-to-moderate asthma.

OBJECTIVE: Exhaled nitric oxide (FE(NO)) was evaluated in children with asthma after 4 to 6 years of treatment with budesonide, nedocromil, or albuterol as needed. STUDY DESIGN: FE(NO), spirometry, total eosinophil count, and serum eosinophil cationic protein levels were obtained from 118 children at the Denver site of the Childhood Asthma Management Program upon completion of treatment and after a 2- to 4-month washout. RESULTS: Budesonide-treated patients had significantly lower median (1st, 3rd quartile) FE(NO) (21.5 [13.2, 84.4] vs 62.5 [26.2, 115.0] ppb, P <.01) and eosinophil cationic protein levels (17.4 [10.1, 24.3] vs 24.0 [15.4, 33.9] mg/dL, P =.05) compared with placebo, whereas no differences were noted between nedocromil and placebo groups. After washout, FE(NO) levels were similar between the three treatments. FE(NO) levels significantly correlated with degree of bronchial hyperresponsiveness, bronchodilator reversibility, allergen skin prick tests, serum IgE, and total eosinophil count. FE(NO) levels were also higher in patients with nocturnal symptoms and in patients requiring beta-agonist use at least once weekly. CONCLUSIONS: Budesonide therapy was more effective than nedocromil in reducing FE(NO). Unfortunately, the effects of long-term budesonide were not sustained after its discontinuation. FE(NO) may be a complementary tool to current practice guidelines in assessing asthma control and medication response.

Anti-Asthmatic Agents↗