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R Beasley

Publications and source records attributed to R Beasley.

At least 37 records · Page 2Linked to original sources
PubMed2002

Sleep disorders: a potential role in New Zealand motor vehicle accidents.

BACKGROUND: The potential role of sleep disorders in New Zealand motor vehicle accidents (MVA) has not been systematically studied. AIMS: To trial a recruitment method and document the frequency of sleep disorders in drivers attending an emergency department with injury following MVA. METHODS: Injured drivers admitted to Wellington Hospital Emergency Department were prospectively recruited by letter and follow-up telephone call. Data from a traffic accident, health and sleep questionnaire and polysomnography were collected and analysed using the SPSS statistical package. RESULTS: Of 120 eligible drivers, 40 (33%) completed the study protocol. The mean age of participants was 44 +/- 17 years. Non-participants were younger (mean age 33 +/- 14 years, P < 0.01) and more often of Asian or Pacific Island ethnicity (P < 0.01). Twenty-seven (67%) felt unrefreshed on waking and 10 (25%) had an elevated Epworth Sleepiness Score (> 10/24). Six (15%) felt drowsy or fell asleep prior to the accident. Sleep disorders were common (40%): obstructive sleep apnoea 14 (35.9%), periodic limb movements of sleep three (7.7%), sleep restriction (< 6 h sleep on a regular basis) five (12.5%), and insomnia one (2.5%). CONCLUSIONS: Daytime somnolence and sleep disorders were commonly found in drivers attending the Emergency Department after accidents resulting in injury. Driver fatigue and sleep disorders should be considered as a potential contributing factor in New Zealand MVAs. Recruitment of drivers following a MVA via the Emergency Department is challenging. Strategies to improve recruitment are discussed.

Accidents, Traffic↗
PubMed2001

Dose-response relation of inhaled fluticasone propionate in adolescents and adults with asthma: meta-analysis.

OBJECTIVE: To examine the dose-response relation of inhaled fluticasone propionate in adolescents and adults with asthma. DESIGN: Meta-analysis of placebo controlled, randomised clinical trials that presented data on at least one outcome measure of asthma and that used at least two different doses of fluticasone. SETTING: Medline, Embase, and GlaxoWellcome's internal clinical study registers. MAIN OUTCOME MEASURES: FEV(1), morning and evening peak expiratory flow, night awakenings, beta agonist use, and major exacerbations. RESULTS: Eight studies, with 2324 adolescents and adults with asthma, met the inclusion criteria. Data on doses of >500 microg/day were limited. The dose-response curve for the raw data began to reach a plateau at around 100-200 microg/day and peaked by 500 microg/day. A negative exponential model for the data, without meta-analysis, indicated that 80% of the benefit at 1000 microg/day was achieved at doses of 70-170 microg/day and 90% by 100-250 microg/day. A quadratic meta-regression showed that the maximum achievable efficacy was obtained by doses of around 500 microg/day. The odds ratio for patients remaining in a study at a dose of 200 microg/day, compared with higher doses, was 0.73 (95% confidence interval 0.49 to 1.08). Comparison of the standardised difference in FEV(1 )for an inhaled dose of 200 microg/day against higher doses showed a difference in FEV(1) of 0.13 of a standard deviation (-0.02 to 0.29). CONCLUSIONS: In adolescent and adult patients with asthma, most of the therapeutic benefit of inhaled fluticasone is achieved with a total daily dose of 100-250 microg, and the maximum effect is achieved with a dose of around 500 microg/day. However, these findings were limited by the lack of data on individual patients and by the paucity of dose-response studies that included doses of >500 microg/day.

Administration, Inhalation↗
PubMed2001

A serological survey of antibodies to rabbit haemorrhagic disease virus (rabbit calicivirus disease) in two rural Central Otago communities.

AIMS: To determine whether individuals from two rural communities with heavy exposure to the Rabbit Haemorrhagic Disease Virus (RHDV) developed antibodies to this virus. METHODS: Sera were assayed using competition ELISA (cELISA) and solid phase ELISA (spELISA). Exposure estimates were based on answers to an interviewer administered questionnaire. RESULTS: Of the 104 participants, 79 were considered to have experienced high or medium exposure, many of whom described specific exposures. There were 58 people who reported contact with RHDV infected bait, organ homogenate mixtures or rabbit body fluids. A one-way analysis of variance (Kruskal Wallis) found that human cELISA results were differently distributed from both strongly RHDV positive rabbits (chi2(1) = 27.37, p < 0.001) and weakly RHDV positive rabbits (chi2(1) = 27.35, p < 0.001). The distribution of assay results in each exposure group did not differ in either cELISA (chi2(2) = 2.49, p = 0.29) or spELISA (chi2(2) = 1.70, p = 0.43). Relatively fewer results were categorised as reactive (two 'barely' positive and two doubtful) than in a previous survey of 493 unexposed people. None of the five positive results categorised by the less specific spELISA occurred in people described as 'barely' positive or doubtful by cELISA. CONCLUSIONS. No serological evidence of infection with RHDV was found in a cohort including many heavily exposed individuals.

Adult↗
PubMed2001

Cumulative and single-dose design to assess the bronchodilator effects of beta2-agonists in individuals with asthma.

With the development of different chlorofluorocarbon (CFC)-free metered dose aerosol and dry powder devices, it is necessary to study and validate the methods used for assessing and comparing their efficacy. This study evaluated the cumulative dose design by determining the bronchodilator response to salbutamol given according to either a high or a low cumulative dose regimen. Adults with asthma (n = 24) were studied in a placebo-controlled, randomized, double-blind, cross-over design. On separate days, cumulative doses of salbutamol (50+50+100+200 or 100+100+ 200+400 or 400+0+0+0 or 0+0+0+0 microg) were given via Turbuhaler with 30 min between doses. The two cumulative dose regimens produced almost identical bronchodilator responses at each time point. The relative dose-potency between the 800- and 400- microg cumulative dose regimens was 0.7 with a 95% confidence interval of 0.5-1.0, excluding the true value of 2. The 400-microg cumulative dose regimen resulted in a higher FEV1 at 115 min than the 400-microg single-dose regimen. There was no difference in the bronchodilator response to the single dose of 50, 100, or 400 microg of salbutamol after either 5 or 25 min. Thus, care should be exercised when using either a cumulative or single-dose design for comparing different beta2-agonists, or different inhalation devices, with respect to their relative dose-potency. In addition, this study provides further evidence that for short-acting beta2-agonists such as salbutamol, lower doses than those normally recommended may be used, and that repeated self-administration of low doses over a period of 60 min may give a better bronchodilator response than a single administration of a high dose.

Administration, Inhalation↗
PubMed2001

The effect of delipidated deglycolipidated (DDMV) and heat-killed Mycobacterium vaccae in asthma.

Experimental and epidemiological evidence supports the hypothesis that exposure to mycobacteria has the potential to suppress the development of asthma and/or atopy and there are reports in the Chinese medical literature of repeated vaccination with inactivated BCG being effective in the management of asthma. Forty-three patients with stable moderately severe asthma who were skin prick test positive to house dust mite were randomized to receive two intradermal injections of either phosphate-buffered saline (placebo), heat-killed Mycobacterium vaccae (0.5 mg), or delipidated deglycolipidated Mycobacterium vaccae (DDMV) (0.05 mg). Markers of asthma severity were measured for 3 mo and blood eosinophil, IgE levels, and the T cell proliferative and cytokine responses were monitored. There were no significant differences between either treatment group and the placebo group for any of the outcome variables. There was also no difference between the treatment groups and placebo for eosinophil, IgE levels, or the T cell proliferative and cytokine response. The results indicate no effect of low dose intradermal DDMV or M. vaccae on asthma severity in patients with established asthma.

Adult↗
PubMed2001

Immunization and symptoms of atopic disease in children: results from the International Study of Asthma and Allergies in Childhood.

OBJECTIVES: This study tested the hypothesis that immunization is related to the prevalence of atopic disease in childhood. METHODS: We used data from the International Study of Asthma and Allergies in Childhood to perform an ecologic analysis of national and local immunization rates for tuberculosis, diphtheria and tetanus toxoids and pertussis (DTP), and measles and prevalence of atopic disease symptoms (asthma, allergic rhinoconjunctivitis, and atopic eczema). RESULTS: In 13- to 14-year-old children, there were significant negative associations with local birth-year immunization rates for DTP and measles but none with rates for tuberculosis. No associations were found in 6- to 7-year-old children. No associations with national immunization rates were found. CONCLUSIONS: International variations in childhood atopic diseases are unlikely to be explained by variations in immunization.

Adolescent↗
PubMed2000

Prevalence and etiology of asthma.

An increased understanding of the causes of asthma is coming from the international comparisons of asthma prevalence, particularly those from the European Community Respiratory Health Survey of asthma prevalence in adults and the International Study of Asthma and Allergies in Childhood. From these and other studies of asthma prevalence, it is possible to draw some tentative conclusions as to the patterns of asthma prevalence worldwide. There are five striking patterns: first, asthma prevalence is increasing worldwide; second, asthma is generally more common in Western countries and less common in developing countries; third, asthma is more prevalent in English-speaking countries; fourth, asthma prevalence is increasing in developing countries as they become more Westernized or communities become urbanized; and fifth, the prevalence of other allergic disorders may also be increasing worldwide. These five key features of the international patterns of asthma prevalence raise major questions about the role of "established" risk factors for the development of asthma. As a result, recent research has expanded to include the study of novel factors that may "program" the initial susceptibility to sensitization or contribute to the development of asthma independent of atopic sensitization. These include various exposures in utero, which are reflected in various perinatal factors measured at birth, and exposures (or lack of exposures) in the early years of life that may make the infant more susceptible to the subsequent development of asthma. These issues are now the focus of an intensive research effort worldwide, and the next few years are likely to see exciting advances in our understanding of the causes of asthma.

Asthma↗
PubMed2000

Association of beta2-adrenergic receptor polymorphisms with severe asthma.

BACKGROUND: There is considerable interest in the role of different candidate loci in the development of asthma. This study investigates the association between asthma severity and previously identified polymorphisms at two sites within the beta2-adrenergic receptor (beta2AR) gene: the Arg16-->Gly16 and Gln27-->Glu27 alleles. METHODS: Restriction enzyme analysis of amplified beta2AR gene products (PCR-RFLP) was used to analyse the frequency of the Arg16-->Gly16 and Gln27-->Glu27 polymorphisms within the beta2AR gene in 95 severe asthmatic patients (with a markedly increased risk of death from asthma), 59 mild asthmatic patients, and a control group of 92 nonasthmatic subjects. RESULTS: The Gly16 polymorphism was significantly associated with asthma severity with odds ratios (95% CI) for the Gly16 allele being 1.56 (1.02-2.40, P = 0.04) and 0. 98 (0.61-1.57, P = 0.92) for the severe and mild asthma groups, respectively. The corresponding odds ratios (95% CI) for Gly16 homozygotes were 1.91 (0.82-4.41, P = 0.13) and 0.82 (0.35-1.92, P = 0.65) for the severe and mild asthma groups, respectively. There was no significant association between either polymorphism at amino acid 27 and asthma or asthma severity. CONCLUSIONS: We conclude that the polymorphisms of amino acids 16 and 27 of the beta2AR gene are not associated with the development of asthma per se, but that the Gly16 polymorphism may play a role in the pathogenesis of asthma severity.

Adult↗
PubMed2000

Seasonal variation in asthma hospitalizations and death rates in New Zealand.

OBJECTIVE: The aim of this study was to determine if there is a seasonal pattern to asthma hospitalizations and mortality in New Zealand. METHODOLOGY: Data for an 18-20 year period were obtained for the whole of New Zealand regarding the number of asthma deaths and hospital discharges in each month, as well as annual population totals (1978-1995 for asthma hospitalizations, 1976-1995 for asthma deaths). Monthly mortality and hospital discharge rates were calculated for the age groups 5-14, 15-44, and those aged 45 years and older. Variation about the mean monthly rates was plotted along a linear timescale to observe the seasonal trend. RESULTS: In the oldest age group (45+), asthma mortality and hospitalization rates peaked in the winter months (July/August). Among the younger age groups, however, mortality and hospitalizations showed different seasonal patterns; peak hospitalization occurred in the early winter months, with peak mortality in the early summer months. CONCLUSIONS: Seasonal variations in the asthma hospitalization and death rates in New Zealand are similar to those from the Northern Hemisphere. The peak mortality in summer for the younger age groups is paralleled by a reduction in hospitalizations in this period, indicating that the increase in mortality may be due to problems of access to medical care.

Adolescent↗