Lung function measurements in children - copsac
Lung function measurements in children - copsac
Lung function measurements in children - copsac
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
RA 08 TSM 133; Respiratory Care Center; Hämeenl<strong>in</strong>na, F<strong>in</strong>land) as previously detailed (25). The<br />
result was assessed by PTcO2 <strong>in</strong> accordance with previous sensitivity analyses (25, 27) and the provocative<br />
dose caus<strong>in</strong>g a 15% drop <strong>in</strong> PTcO2 was estimated from the dose response curves fitted<br />
with a logistic <strong>function</strong>.<br />
Bronchiolitis<br />
Bronchiolitis was def<strong>in</strong>ed as an acute respiratory illness before the age of 2 years based on symptoms<br />
of coryza progress<strong>in</strong>g over a few days to cough, tachypnea, chest retraction and wide spread<br />
crackles, wheezes or both (28) diagnosed by the COPSAC cl<strong>in</strong>ical research unit doctor or admission<br />
acutely to the local hospital for such symptoms.<br />
RSV bronchiolitis<br />
RSV bronchiolitis was def<strong>in</strong>ed as bronchiolitis with a positive ELISA test for RSV <strong>in</strong>fection with<strong>in</strong><br />
10 days of the acute episode.<br />
Acute severe wheezy exacerbations<br />
Acute severe wheezy exacerbations was def<strong>in</strong>ed as an acute obstructive respiratory illness diagnosed<br />
by the COPSAC cl<strong>in</strong>ical research unit doctor and judged to be a severity requir<strong>in</strong>g treatment<br />
with oral or high-dose <strong>in</strong>haled corticosteroids (>800 micg budesonide/day) or hospitalizations<br />
caused by airway symptoms where an anti-asthmatic drug was prescribed (pseudocroup episodes<br />
were excluded).<br />
Control group<br />
Children who developed neither bronchiolitis nor acute wheezy exacerbations before age 2 were<br />
considered as controls.<br />
Statistics<br />
<strong>Lung</strong> <strong>function</strong> measurement data (FEV 0.5 and PD15) were calibrated with lifespan and birth length<br />
<strong>in</strong> accordance with previous lung <strong>function</strong> analyses of the newborn (29) calculated by a generalized<br />
l<strong>in</strong>ear model. Lifespan at exam<strong>in</strong>ation date was calculated as the sum of estimated gestational age <strong>in</strong><br />
weeks and weeks s<strong>in</strong>ce birth. The lung <strong>function</strong> <strong>measurements</strong> were log transformed and we used a<br />
multivariable logistic regression model to calculate adjusted odds ratios and 95% confidence <strong>in</strong>tervals<br />
us<strong>in</strong>g SAS version 9.1. Outcome variable was RSV bronchiolitis compared to control group.<br />
Confounder adjustment <strong>in</strong>cluded mothers smok<strong>in</strong>g dur<strong>in</strong>g 3 rd trimester (dichotomized) and gender.<br />
4