Approaches to asthma management. Realities and recommendations

As asthma prevalence continues to increase, so does its impact on public health and on health care systems. Despite the prescription of more antiasthma medications than ever before, morbidity and mortality associated with asthma continue to increase. The focus of asthma therapy is changing, with a greater emphasis on control of the inflammatory rather than the bronchoconstrictive component. Several sets of guidelines recently developed by groups of asthma specialists clearly reflect this new focus. While such recommendations are intended to help physicians more accurately diagnose asthma by severity and better manage its symptoms, uniformity in both areas is lacking. Disparities are seen not only among physicians overall but also among primary care physicians compared with subspecialists. New survey data help to illustrate how reality--the clinical approaches of these physician subgroups--differs from current recommendations. Physicians who treat patients with asthma may find that their approaches are in agreement with those of their peers. Nonetheless, they may also find that they deviate from guidelines that could improve clinical outcome for a substantial number of patients with asthma.

Dose-response study of inhaled salmeterol in asthmatic patients with 24-hour spirometry and Holter monitoring

Salmeterol is a new long-acting beta 2-selective adrenoceptor agonist. In this double-blind, 6-way crossover study, four single doses of salmeterol by metered dose inhaler (12.5, 25, 50, 100 micrograms) were compared with albuterol aerosol 200 micrograms and placebo in 24 patients with moderate asthma with 24-hour pulmonary function testing and Holter monitoring. Salmeterol was an effective bronchodilator at each dose evaluated and demonstrated a greater increase in FEV1 above baseline, a slightly slower onset and a longer duration of bronchodilation than albuterol. Median durations of bronchodilation were 9.0, 15.6, 13.4, and 18.4 hours with increasing doses of salmeterol in comparison to 4.2 hours for albuterol. Holter monitoring showed (1) a mean maximum heart rate 2 to 5 bpm higher after salmeterol 50 and 100 micrograms compared with placebo and (2) supraventricular premature beats (> 30 per hour or > 100 per 24 hours) more often in the salmeterol 100-micrograms group (13% to 17% of patients) than in the placebo (4%), albuterol (4% to 8%), or other salmeterol groups (4% to 9%). These differences were not statistically significant. Tremor and palpitations were the most frequently reported drug-related adverse events and their frequencies increased with increasing doses of salmeterol. This study demonstrated that single doses of salmeterol given by metered dose inhaler over an 8-fold range possess substantial, long-lasting bronchodilator activity.

A comparison of salmeterol with albuterol in the treatment of mild-to-moderate asthma

BACKGROUND

An effective, long-acting bronchodilator could benefit patients with asthma who have symptoms not controlled by antiinflammatory drugs. We compared a new long-acting, inhaled beta 2-adrenoceptor agonist, salmeterol, with a short-acting beta 2-agonist, albuterol, in the treatment of mild-to-moderate asthma.

METHODS

We randomly assigned 234 patients (150 male and 84 female patients 12 to 73 years old) to one of three treatment groups: one group received 42 micrograms of salmeterol twice daily, one received 180 micrograms of albuterol four times daily, and one received placebo. Treatment was assigned in a double-blind fashion, and all patients could use supplemental inhaled albuterol as needed during the 12-week treatment period.

RESULTS

Measurements of the forced expiratory volume in one second, performed hourly for 12 consecutive hours, showed that a single dose of salmeterol produced a greater mean area under the curve than two doses of albuterol taken 6 hours apart (6.3 vs. 4.9 liter.hr, P < 0.05). The difference was significant on day 1 and at week 4 of the study, but not at week 8 or 12. Salmeterol was also more effective than albuterol or placebo (with albuterol taken as needed) in increasing the morning peak expiratory flow rate: salmeterol induced a mean increase of 24 liters per minute over the pretreatment values, as compared with a decrease of 6 liters per minute with albuterol (P < 0.001) and an increase of 1 liter per minute with placebo (P = 0.002). The mean overall symptom score was improved most by salmeterol treatment (P < 0.05), with the number of days with symptoms and of nights with awakenings decreasing by 22 percent and 52 percent, respectively; there were no differences in results between albuterol treatment and placebo administration. We found no evidence of tolerance to the bronchodilating effects of salmeterol, and adverse reactions to all the treatments were infrequent and mild.

CONCLUSIONS

For the management of mild-to-moderate asthma, salmeterol given twice daily is superior to albuterol given either four times daily or as needed.

Pemirolast, a new oral nonbronchodilator drug for chronic asthma

Pemirolast is a new oral, nonbronchodilator antiallergy medication that is being evaluated for the therapy of asthma. In this multicenter, double-blind, randomized study, 96 patients with mild asthma received pemirolast, 50 mg (n = 34); pemirolast, 25 mg (n = 31); or placebo (n = 31) BID for 6 weeks. Patients were evaluated weekly at the research centers; they maintained daily symptom diaries and measured peak expiratory flow rates twice a day. Methacholine challenge was performed at the start and end of the study. Results with pemirolast, 50 mg BID, showed statistically significant decrease in nocturnal symptoms (P = .02), in composite symptom scores (P = .02) and in bronchodilator use (P = .05) when compared with placebo. There were no statistically significant differences between treatments in pulmonary function tests or in methacholine challenge sensitivity. Pemirolast, 25 mg BID, did not differ from placebo. There were no significant adverse effects. Pemirolast, 50 mg BID, demonstrated sufficient antiasthma activity to warrant further studies in patients with more severe asthma and with higher doses.

Comparison of intranasal cromolyn sodium, 4%, and oral terfenadine for allergic rhinitis: symptoms, nasal cytology, nasal ciliary clearance, and rhinomanometry

Topical intranasal cromolyn sodium, 4% solution, and oral terfenadine, 60 mg tablets, both relieve symptoms of allergic rhinitis with few or no adverse effects, but no comparison of their relative efficacy has been reported. In this double-blind, double-dummy study, 79 patients, ages 12-56 years with symptoms of allergic rhinitis, were randomized to receive either active cromolyn sodium, 1 spray in each nostril QID, or active terfenadine BID along with the appropriate placebo spray or tablet for 4 weeks following a 1-week baseline qualification period. Patients' daily symptom scores were reviewed weekly and constituted the primary efficacy measures. Changes in nasal cytology, nasal ciliary clearance, and rhinomanometry were also assessed. The presence of adverse effects and the overall score of medication efficacy at the end of each week was recorded. The cromolyn sodium and terfenadine groups had comparable baseline scores for severity of allergic rhinitis symptoms and both treatments resulted in significant improvement (P less than .0001) with no statistical difference between them for total symptom scores at the end of 4 weeks. Eosinophils in nasal samples were decreased significantly in the cromolyn treated group with no significant change in the terfenadine-treated group. There were no significant differences between treatment groups in ciliary clearance or rhinomanometry. Adverse effects were uncommon and mild. We conclude that cromolyn sodium and terfenadine are comparably effective and well-accepted treatments for allergic rhinitis.

Vocal cord dysfunction in a child with asthma

Vocal cord dysfunction is uncommon in children. We present the case of a 12-year-old boy with a history of mild, intermittent asthma from 7 to 10 years of age. Subsequently, severe, rapid-onset attacks of respiratory distress occurred with increasing frequency. After a life-threatening attack of airway obstruction with 3 minutes of apnea, he was hospitalized for diagnostic studies. Although pulmonary function tests were normal, laryngoscopy under general anesthesia revealed extremely severe vocal cord spasm induced by minimal contact of the laryngoscope. It required intravenous lidocaine and muscle relaxant to reverse. Spasm was not demonstrable one week later on repeat laryngoscopy and bronchoscopy. No structural abnormalities were seen. There was considerable family stress exacerbated by anxiety about the patient's illness. Parents were told that the condition was different from asthma and probably functional in origin. There have been no further episodes, possibly due to counseling and education in relaxation techniques as well as oral pharmacotherapy for asthma with avoidance of inhaled medications.

Effects of albuterol and procaterol on exercise-induced asthma

Procaterol and albuterol, beta agonists, were studied using a placebo-controlled, repeated exercise challenge design in order to assess their duration of effectiveness in both bronchodilation and in modifying exercise-induced asthma (EIA). Fifty-three subjects aged 12 to 50 years who had at least a 20% drop in FEV1 during a screening exercise tolerance test were entered. Subjects took two inhalations of procaterol (10 micrograms/inhalation), albuterol (90 micrograms/inhalation), or placebo. Thirty minutes later they exercised on a treadmill at a workload sufficient to induce greater than or equal to 80% aerobic O2 consumption for six minutes. Pulmonary function was measured before and serially for 30 minutes after exercise. The same exercise challenge was repeated three, six, and nine hours after drug administration. Both procaterol and albuterol bronchodilated and modified EIA at 30 minutes and three hours, mean drops in FEV1 being 8.2 and 9.7% respectively at 30 minutes and 16.8 and 16.3% at three hours. This was compared with placebo falls of 30% and 26%. At six hours the subjects' response was similar after both procaterol and albuterol, and fewer subjects had a 20% fall in FEV1 than with placebo, although protection afforded by both beta agonists was substantially less than at three hours. Both drugs were tolerated well.

Evaluation of the safety and efficacy of multiple doses of azelastine to adult patients with bronchial asthma over time

Azelastine is a new oral antiasthma agent with bronchodilating and antiallergic properties. This 12-wk study compared azelastine (2, 4, 6, and 8 mg) and placebo given twice a day in asthmatics 12 to 60 yr of age requiring daily bronchodilator therapy. Patients were allowed albuterol aerosol, short-acting theophylline, and pseudoephedrine only as needed. The study was completed by 221 asthmatic subjects. No significant differences in symptoms, medication, or pulmonary function existed between groups at baseline. Analysis of the zero hour FEV1 before azelastine administration on eight occasions during the 12 wk of therapy indicated an increasing slope for azelastine 6 mg that was statistically different from that of placebo; similarly, the slope for azelastine 4 mg showed the same trend, but it did not reach statistical significance. All azelastine groups had significant reductions of as-needed medication after 1 wk; only in the 4-mg and 6-mg groups was this reduction sustained for 12 wk. Asthma symptom scores and peak expiratory flow measurements remained stable in the azelastine groups despite significant reductions in concomitant medication administration. Side effects were minor and included: altered taste (30.1 to 51.9%), drowsiness (6.0 to 16.9%), and dry mouth (3.8 to 6.1%). The occurrence of these adverse events decreased with time throughout the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Beta 2 adrenergic agonists--oral or aerosol for the treatment of asthma?

Beta 2 adrenergic agonists, especially in aerosol formulations, are often used as first-line medications for treating the symptoms of bronchial asthma. Although oral forms of these medications may result in greater improvement in small airway function, comparative studies of these two routes of administration show that inhaled beta 2 adrenergic bronchodilators have a more rapid onset of activity, are as long lasting, and as effective in improving pulmonary function as their oral forms. Moreover, they are equally effective at much lower dosages which results in fewer adverse effects. Their use in metered-dose inhalers, nebulizers, and breath-activated devices, is improving asthma therapy.

Procaterol metered-dose inhaler: a multiclinic study evaluating the efficacy and safety in patients with asthma

Procaterol hydrochloride aerosol, a potent beta 2-adrenergic bronchodilator, was evaluated in a double-blind, placebo-controlled study for efficacy and safety in 210 patients with documented mild to moderate reversible airway obstruction. Patients were randomized to receive procaterol in two inhalations (high dose) or one inhalation (low dose), 0.01 mg/inhalation, three times daily, or placebo. Pulmonary function tests were recorded at five and 30 minutes and hourly for eight hours after the first dose and following 1 and 2 weeks of treatment. Both doses of procaterol produced significantly greater improvement in PFTs at one hour and for up to seven hours after dosing compared with placebo (p less than 0.05). Mean percent increases in FEV1 were 35% in the high-dose group and 29% in the low-dose group at week 2. The high-dose group showed no loss of duration of bronchodilation with continued dosing. Improvement in PFTs and peak flow rates was significantly greater in the high-dose than in the low-dose group (p less than 0.05). Tremor was the most frequent side effect. Procaterol had no effect on electrocardiograms, heart rate, blood pressure, or clinical laboratory tests. The high dose of procaterol aerosol was shown to be an effective and well-tolerated bronchodilator with a rapid onset and long duration of action.

Albuterol treatment for children with asthma: a comparison of inhaled powder and aerosol

A dose-ranging study and a 12-week treatment study were conducted in children with asthma, aged 4 to 12 years, to assess the efficacy and safety of albuterol inhaled as either an aerosol or as dry powder. Both studies were double-blind and placebo-controlled with randomized assignment to treatment. The dose-ranging study in 30 patients indicated that similar single doses of albuterol aerosol and powder had comparable effects with the intermediate doses (i.e., 180 micrograms of aerosol and 200 micrograms of powder) providing effective bronchodilation with minimal adverse effects. In the subsequent 12-week, parallel-group study, 204 children received albuterol as either aerosol, 180 micrograms, or powder, 200 micrograms four times a day. Both formulations were equally effective with no untoward cardiovascular effects and only one incident of mild tremor. Among those children who expressed a preference for one of the delivery systems, significantly more children preferred the powder (44% versus 26%, p less than 0.01). Albuterol taken four times a day as either aerosol or dry powder is both effective and well tolerated in children with asthma.

A comparative tolerance study of terfenadine-pseudoephedrine combination tablets and pseudoephedrine tablets in patients with allergic or vasomotor rhinitis

In this multicentre, double-blind, randomized, parallel group study, 315 patients with allergic or vasomotor rhinitis were treated on a twice daily dosing schedule with either a 60 mg terfenadine-120 mg pseudoephedrine hydrochloride combination or 120 mg pseudoephedrine hydrochloride (extended release) for 2 weeks. No clinically significant differences between the two groups were noted in body weight, temperature, respiration rate or blood pressure following the treatment period. An increase in mean heart rate of approximately 5 beats/min from entry to the final clinic visit was noted in both treatment groups. No clinically significant changes were noted in either treatment group when pre- and post-treatment electrocardiograms were compared. There were also no clinically significant alterations in laboratory values, which included serum chemistry, haematology and urinalysis, within or between either group. The adverse events profiles for both groups were similar. The most frequent adverse event was insomnia, in 40 (25.3%) patients given the terfenadine-pseudoephedrine combination and in 42 (26.8%) of those given pseudoephedrine. No unusual or unexpected adverse events were reported.

A multicenter, open study of the non-sedating antihistamine, terfenadine (Seldane), in the maintenance therapy of seasonal allergic rhinitis

A multicenter open study was conducted throughout the 1984 fall pollen season to assess the possible development of tolerance or loss of efficacy to terfenadine in the maintenance therapy of patients with seasonal pollinosis. Patients with proven allergic pollinosis were entered into a 1-week initial treatment period taking terfenadine 60 mg bid and only those who responded to the initial treatment with "moderate" to "complete" relief continued on terfenadine throughout a 4 to 11-week pollen season for evaluation of continued efficacy. A total of 179 patients from five study centers were enrolled in the initial treatment period and 154 (86%) responded to terfenadine with "moderate" to "complete" relief of symptoms. Of these 154 patients who continued terfenadine treatment, approximately 90% of the patients maintained the same degree of relief throughout the pollen season. All symptoms of seasonal pollinosis including nasal congestion improved significantly the first day of treatment. This improvement in symptoms continued during the first week and remained unabated throughout the pollen season. The incidence of adverse events was low with sedation being reported by only 2.8% of patients at some time point during the study. It is concluded that terfenadine is a safe and effective non-sedating antihistamine in the maintenance therapy of seasonal allergic pollinosis and that tolerance is not noted during continued administration.