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Biomedical subjects

Richard Beasley

Publications and source records attributed to Richard Beasley.

52 records · Page 3Linked to original sources
PubMed2004

The pulmonary and extra-pulmonary effects of high-dose formoterol in COPD: a comparison with salbutamol.

OBJECTIVES: Formoterol, a beta(2) agonist with a rapid onset of effect and long duration of action, can be used as maintenance and reliever medication for asthma and COPD. We compared the pulmonary and extra-pulmonary effects of cumulative doses of formoterol and salbutamol in patients with COPD to assess efficacy and safety. METHODOLOGY: In a randomized, double-blind, cross-over study, 12 patients with moderate to severe COPD inhaled, via Turbuhaler, 10 doses of formoterol (total metered dose, 120 microg, equivalent to a 90- microg delivered dose), salbutamol (total metered dose 2000 microg) or placebo at 2-min intervals on separate days. The effects on lung function (FEV(1) and PEF), heart rate, blood pressure, oxygen saturation, corrected QT interval (QTc), T-wave height and plasma potassium were assessed before each dose, 15 min after each dose, and at half-hourly intervals for 3 h following the final dose. RESULTS: Inhalation of formoterol or salbutamol resulted in significant improvement in lung function (measured 30 min after the last dose) when compared with placebo. There were no clinically important or statistically significant changes in heart rate, QTc, T-wave height, plasma potassium, oxygen saturation, or systolic and diastolic blood pressures with formoterol or salbutamol. One patient developed ventricular trigeminy after both formoterol and salbutamol. She had had ventricular ectopics on her screening electrocardiogram. CONCLUSION: Formoterol and salbutamol both produced significant improvement in lung function and were similarly well tolerated in high doses, as might be taken by a patient for relief of COPD symptoms.

Adrenergic beta-Agonists↗
PubMed2004

Budesonide once versus twice-daily administration: meta-analysis.

OBJECTIVES: The aim of this study was to examine the efficacy of budesonide administered once daily compared to twice daily in asthma. METHODOLOGY: Meta-analysis of randomised controlled trials comparing budesonide administered once versus twice a day that presented data on at least one clinical outcome measure was conducted. RESULTS: A total of 10 studies, with 1922 children and adults with asthma, met the inclusion criteria. These studies were performed predominantly with mild to moderate asthmatic patients, using doses of budesonide ranging from 200 to 800 microg per day. There was no significant difference between daily dosing once or twice for all the clinical outcome variables, including withdrawals due to asthma, for which the odds ratio was 1.0 (95% confidence interval, 0.65-1.52). CONCLUSIONS: In mild to moderate asthma a once-daily budesonide regimen has a similar efficacy to a twice-daily regimen in doses up to 800 microg per day. A once-daily regimen has potential advantages in terms of patient compliance and satisfaction, when used in clinical practice.

Adolescent↗
PubMed2003

Use of isotonic nebulised magnesium sulphate as an adjuvant to salbutamol in treatment of severe asthma in adults: randomised placebo-controlled trial.

BACKGROUND: Intravenous magnesium can cause bronchodilation in treatment of severe asthma, however its effect by the nebulised route is uncertain. We aimed to assess the effectiveness of isotonic magnesium sulphate as an adjuvant to nebulised salbutamol in severe attacks of asthma. METHODS: We enrolled 52 patients with severe exacerbations of asthma presenting to the emergency departments at two hospitals in New Zealand. A severe exacerbation was defined as a forced expiratory volume at 1 s (FEV(1)) of less than 50% predicted 30 min after initial administration of 2.5 mg salbutamol via nebulisation. In this randomised double-blind placebo-controlled trial patients received 2.5 mg nebulised salbutamol mixed with either 2.5 mL isotonic magnesium sulphate or isotonic saline on three occasions at 30 min intervals. The primary outcome measure was FEV(1) at 90 min. Analysis was per protocol. FINDINGS: At 90 min the mean FEV1 in the magnesium group was 1.96 L (95% CI 1.68-2.24) and in the saline group 1.55 L (1.24-1.87). The difference in the mean FEV(1) between the magnesium and saline groups was 0.37 L (0.13-0.61, p=0.003). INTERPRETATION: Use of isotonic magnesium as an adjuvant to nebulised salbutamol results in an enhanced bronchodilator response in treatment of severe asthma.

Administration, Inhalation↗
PubMed2003

International patterns of the prevalence of pediatric asthma the ISAAC program.

Like so much research, the findings from the ISAAC program have raised more questions than they have answered. Despite their limitations, the ISAAC findings provide the basis for further studies to investigate factors that potentially contribute to these international patterns and may lead to novel public health and pharmacologic intervention strategies that reduce the prevalence and severity of asthma worldwide.

Asthma↗
PubMed2003

Rhinovirus is not detectable in peripheral lung tissue after asthma death.

OBJECTIVE: Viral infections are associated with both mild and severe exacerbations of asthma and may therefore be associated with asthma death. As such we hypothesized that it might be possible to detect rhinovirus (RV), the virus most frequently implicated in acute asthma, in lung tissue from patients who died from asthma. METHODOLOGY: We studied archival, wax-embedded lung tissue obtained postmortem from: (i) patients who died from asthma (n = 12), (ii) asthma patients with non-asthma-related death (n = 3), and (iii) non-asthmatic individuals who died from unrelated causes (n = 3). A validated reverse transcription-polymerase chain reaction (RT-PCR) assay was used to detect RV. To confirm RNA preservation, RT-PCR was used to detect expression of the constitutive gene adenine-phosphoribosyl-transferase (APRT). Sensitivity of the assay was assessed using wax-embedded RV-infected cells. RESULTS: Sensitivity of RT-PCR for RV in wax-embedded sections was similar to previous studies (approximately 100 viral copies). Specimens used for study were predominantly of alveolar and small airway origin (< 2 mm). All tissues examined were negative for the presence of RV mRNA and positive for APRT mRNA. CONCLUSIONS: RV infection of the lower airway may be an uncommon cause of fatal asthma. Alternatively, RV may not extend to peripheral airways and more proximal tissue sampling or PCR assays for other viruses may be required to determine an association between viral respiratory tract infection and fatal asthma.

Adolescent↗
PubMed2003

Pilot study of the safety and effect of intranasal delipidated acid-treated Mycobacterium vaccae in adult asthma.

OBJECTIVE: There is epidemiological and experimental evidence that exposure to mycobacteria has the potential to suppress the development of atopy and/or asthma. Delipidated, deglycolipidated and arabinogalactan-depleted autoclaved Mycobacterium vaccae (delipidated acid-treated M. vaccae) has been shown to suppress allergen-induced airway eosinophilia in mice. METHODOLOGY: Thirty-seven adults with stable moderately severe asthma who were skin prick test-positive to house dust mite were randomized to receive two doses 2 weeks apart of delipidated acid-treated M. vaccae (first dose 0.4 mg and second dose 0.8 mg) or phosphate buffered saline, given as drops intranasally. Safety, tolerability and markers of asthma severity (including peak flow, FEV1, major and minor exacerbations, symptom scores and beta-agonist use), and nasal symptom scores, blood eosinophil and IgE levels were monitored for 8 weeks. RESULTS: Delipidated acid-treated M. vaccae was safe and well tolerated although there was an occasional mild local reaction. There were no statistically significant differences between the treatment group and placebo for any of the outcome variables. CONCLUSIONS: There is a requirement to elucidate the reasons why mycobacterial-based vaccines have not shown equivalent efficacy in human trials compared with animal models. The role of factors such as duration of disease, route of administration and the active component of mycobacteria need to be addressed.

Administration, Intranasal↗
PubMed2002

Do natural health food stores require regulation?

AIM: To compare advice provided by health food stores (HFS) and pharmacies in relation to medical conditions and assess the need for regulation of HFS. METHODS: We assessed the advice provided by 26 health food stores (HFS) and 26 pharmacies to an individual presenting with symptoms suggestive of moderate to severe asthma who had not seen a general practitioner. RESULTS: The advice provided by the two stores differed markedly. 22/26 pharmacy staff diagnosed asthma/probable asthma, whereas only 15/26 HFS staff reached the same conclusion. 92.3% of pharmacy staff compared to 34.6% of HFS staff referred the investigator to a doctor; 5 HFS advised the investigator against seeing a doctor. A wide variety of remedies were recommended by the HFS, none of which are known to be beneficial in the treatment of asthma. CONCLUSION: HFS promoting herbal products for medical conditions should be regulated in a similar fashion to shops that dispense pharmaceutical products.

Adult↗
PubMed2002

An inverse correlation between estimated tuberculosis notification rates and asthma symptoms.

BACKGROUND: A recent ecological analysis demonstrated a strong inverse relationship between tuberculosis notification rates and the prevalence of asthma symptoms in 13-14-year-old children as obtained from the International Study of Asthma and Allergies in Childhood (ISAAC). However, the analysis was confined to the 23 countries in which the tuberculosis notification rates were considered to be of sufficient validity. METHODS: A similar analysis was performed using estimated tuberculosis incidence rates obtained from the World Health Organization Global Tuberculosis Programme and asthma symptom prevalence data from ISAAC for both the 6-7 and 13-14 years age groups in 38 and 55 countries, respectively. RESULTS: For the 6-7-year-old children, there was a significant inverse relationship between estimated tuberculosis incidence and the prevalence of key asthma symptoms. However, in the 13-14 year age group, a significant inverse relationship was only demonstrated for 'asthma ever'. CONCLUSION: The present study extends the inverse relationship between tuberculosis rates and asthma prevalence to the 6-7-year-old age group and suggests that the association, if causal, may be stronger at this younger age.

Adolescent↗
PubMed2002

The relationship between FEV1 and PEF in the assessment of the severity of airways obstruction.

OBJECTIVE: International consensus guidelines suggest that in asthma and chronic obstructive pulmonary disease (COPD), measurements of FEV1 and PEF are equivalent in the assessment of the degree of airflow obstruction when expressed as the per cent of predicted values. METHODOLOGY: In this retrospective study, 2,587 paired measurements of PEF and FEV1 performed by 101 adult patients with asthma (n = 56) and COPD (n = 45) attending an outpatient chest clinic were obtained. The mean differences between FEV1 and PEF measurements when expressed as the percentage of predicted values was determined. The level of agreement between the two measurements in the classification of asthma severity (life-threatening, severe, moderate and mild asthma determined by PEF or FEV1 measurements of <30%, 30-60%, 60-80%, and >80% of the predicted values, respectively) was determined. RESULTS: There was considerable variability between measurements of FEV1 and PEF when expressed as % predicted values. In both asthma and COPD, the FEV1% predicted was smaller than the PEF % predicted, with the mean difference being -10.9% (95% CI, -12.8% to -8.9%) with limits of agreement of -35.4% to +13.6%. The weighted Kappa statistic for agreement was 0.59 (95% CI, 48-70%) in the classification of the severity of airflow obstruction. CONCLUSION: When expressed as percentage of predicted values, PEF and FEV1 values are not equivalent. We recommend that guidelines be modified to state that across the spectrum of the severity of airflow obstruction there is considerable variability between measurements of FEV1 and PEF when expressed as % predicted such that the FEV1 may be as much as 35% lower or up to 15% higher than the PEF for patients with obstructive lung diseases.

Adult↗
PubMed2002

The burden of asthma with specific reference to the United States.

During the second half of the 20th century, the increasing prevalence, morbidity, economic burden, and, in some countries, mortality from asthma have generated worldwide concern. The prevalence in the United States and other English-speaking countries is higher than that in most other countries, but worldwide variations cannot be explained by current knowledge of recognized risk or protective factors. According to hospital admission rates, asthma morbidity rates have also risen throughout the world during the past 40 years. These trends are likely due to many different factors, including an increase in the prevalence of severe asthma. Asthma mortality rates gradually declined in the United States during the 1960s and 1970s but have exhibited a substantial, progressive increase during the past 20 years. This trend stands in contrast to those in most other western countries, where asthma mortality rates have generally been decreasing during the 1990s. In both western and developing countries, the considerable economic burden of asthma disproportionately affects individuals with severe disease. This observation illustrates the potential for reducing the costs associated with asthma through management approaches that have been proven to reduce morbidity and mortality.

Adolescent↗