Biomedical subjects

Robert E Dales

Publications and source records attributed to Robert E Dales.

3 recordsLinked to original sources

PubMed2003

The role of fungal spores in thunderstorm asthma.

STUDY OBJECTIVES: To document the existence and investigate the etiology of "thunderstorm asthma," which has been reported sporadically over the past 20 years. DESIGN: We assessed the relationship between thunderstorms, air pollutants, aeroallergens, and asthma admissions to a children's hospital emergency department over a 6-year period. RESULTS: During thunderstorm days (n = 151 days) compared to days without thunderstorms (n = 919 days), daily asthma visits increased from 8.6 to 10 (p < 0.05), and air concentrations of fungal spores doubled (from 1,512 to 2,749/m(3)), with relatively smaller changes in pollens and air pollutants. Daily time-series analyses across the 6 years of observation, irrespective of the presence or absence of thunderstorms, demonstrated that an increase in total spores, equivalent to its seasonal mean, was associated with a 2.2% (0.9% SE) increase in asthma visits. CONCLUSIONS: Our results support a relationship between thunderstorms and asthma, and suggest that the mechanism may be through increases in spores that exacerbate asthma. Replication in other climates is suggested to determine whether these findings can be generalized to other aeroallergen mixes.

Air Pollutants↗

PubMed2003

A spirometry-based algorithm to direct lung function testing in the pulmonary function laboratory.

OBJECTIVE: To design a spirometry-based algorithm to predict pulmonary restrictive impairment and reduce the number of patients undergoing unnecessary lung volume testing. DESIGN: Two prospective studies of 259 consecutive patients and 265 consecutive patients used to derive and validate the algorithm, respectively. SETTING: A pulmonary function laboratory of a tertiary care hospital. PATIENTS: Consecutive adults referred to the laboratory for lung volume measurements and spirometry. MEASUREMENTS: The sensitivity of the algorithm for predicting pulmonary restriction and the cost savings associated with its use. RESULTS: Total lung capacity correlated strongly with FVC (r = 0.66) and showed an inverse correlation with the FEV(1)/FVC ratio (r = - 0.41). According to the algorithm, only patients with an FVC < 85% of predicted and an FEV(1)/FVC ratio >or= 55% required lung volume measurements following spirometry. The algorithm had a high sensitivity for predicting restriction and a high negative predictive value (NPV) for excluding restriction (sensitivity, 96%; NPV, 98%). The diagnostic properties of the algorithm were reproducible in the validation study. Application of the algorithm would eliminate the need for lung volume testing in 48 to 49% of patients referred to the pulmonary function test (PFT) laboratory, reducing costs by 33%. CONCLUSIONS: A spirometry-based algorithm accurately excludes pulmonary restriction and reduces unnecessary lung volume testing in the PFT laboratory almost in half.

Algorithms↗

PubMed2002

Effect of airborne allergens on emergency visits by children for conjunctivitis and rhinitis.

The effect of fungal spores and pollen grains on morbidity from childhood conjunctivitis and rhinitis is mostly unknown. We therefore studied the association between daily concentrations of these airborne allergens and daily emergency visits to a children hospital between 1993 and 1997. An increase of 551 basidiomycetes spores per m(3), or of 72 ragweed grains per m(3), was associated with an increase of about 10% in visits for conjunctivitis and rhinitis (p<0.01). Our results suggest that conjunctivitis and rhinitis could be caused by fungal spores and pollens in the air.

Air Pollutants↗