RESULTS
Totally, 249 children with asthma were enrolled. Twelve of them were excluded because three of them didn’t come the control visit to perform the tests, five of them had acute respiratory infection that may affect FeNO measurement and four of them didn’t use their controller therapy appropriately. Finally, 228 patients(median age[interquartile range, IQR] 10.7[8.4-12.9] years) completed the study, of whom 132(57.9%) were boys. Study population performed 145 PACT, 83 ACT and 221 PAQLQ tests. Asthma follow-up duration was similar for older(> 12 yrs) and younger patients(<12 yrs)(p=0.44). All of the patients underwent FeNO and lung function .
For the whole study population, the medians(IQR) were 22(18-25) for PACT; 22(18-24) for ACT; 5.9(4.9-6.6) for PAQLQ total; 5.2(4.2-6.4) PAQLQ symptoms domain; 6.0(5.1-6.7) PAQLQ activities domain; 6.2(5.2-6.9) for PAQLQ emotions domain; 19(14-27) for FeNO; 93(87-103) for FEV1(expected%); 0.98(0.93-1.05) for FEV1/FVC(ratio) and 89(79-112) for FEF25-75(expected%). Total PAQLQ and symptoms domain were significantly higher for participants <12 years old than those > 12 years old(PAQLQ total: median(IQR) for <12 yrs 6.1(5.2-6.6), > 12 yrs 5.6(4.4-6.5), p=0.018; symptoms domain: median[IQR] for <12 yrs 5.4(4.5-6.6), > 12 yrs 5.0(3.7-6.1), p=0.022). PAQLQ activities and emotions domains were similar for age groups(p=0.092 and 0.242, respectively). Also, FeNO was significantly higher for the older age group(median[IQR] for <12 yrs 18(14-27), > 12 yrs 21(16-32), p=0.023). There were no difference for lung function between age groups(p>0.05).
According to GINA criteria, 84.2% of the study population(n=192) had “well-controlled” asthma, while 9.6% and 6.1% of them were identified as “partially-controlled” and “uncontrolled” asthma. 15.7%of patients had “not-well controlled” asthma. Older patients(> 12 yrs) had more frequently “not well-controlled” asthma than younger ones(<12 yrs)(22.9%[19] versus 11.7%[17], respectively, p=0.026). Female and older patients had more frequently “not well-controlled” asthma defined by GINA criteria than males and younger ones(p=0.012 and 0.005, respectively). Besides, atopic patients had more frequently “well-controlled” asthma according to GINA criteria than those without atopy(p=0.021). The score of PACT, ACT and PAQLQ were higher for the patients with “well-controlled asthma”(p<0.001), whereas medians of FeNO and lung function of the groups were not different(Table 1).
The only significant correlation was between PAQLQ and PACT or ACT(r=0.658 and r=0.789, p<0.001, respectively). FeNO and lung function had no correlation with neither each other nor other tests (p>0.05)(data not shown).
Comparing PACT to GINA criteria for “well controlled asthma” resulted in an AUC of the ROC curve of 0.79(95%CI 0.70-0.88, p<0.001). The cut-off level of 21.5 has the highest sensitivity and specifity(0.609 and 0.882, respectively). As a result, the cut-off level of 22(PACT> 22 for “well controlled asthma”) provided the highest compatibility of PACT with GINA (correctly classified 93[64.1%], κ=0.221, p<0.001). Likewise, the ROC curve analyses of ACT resulted in an AUC of 0.86(95%CI 0.76-0.96, p<0.001). The cut-off level of 20.5 has the highest sensitivity and specifity(0.719 and 0.895, respectively). Ultimately, the cut-off level of 21(ACT> 21 for “well controlled asthma”) provided the highest compatibility of ACT with GINA (correctly classified 63[75.9%], κ=0.473, p<0.001). By the same way, the ROC curve analyses of PAQLQ revealed an AUC of 0.76(95% CI 0.67-0.84, p<0.001). The cut-off level of 5.85 has the highest sensitivity and specifity(0.591 and 0.828, respectively). Finally, the cut-off level of 5.9(PAQLQ> 5.9 “well controlled asthma”) provided the highest compatibility of PAQLQ with GINA (correctly classified 139[62.9%], κ=0.150, p<0.001)(Table 2). The performance of different cut-off values of PACT and ACT were shown in table 3 and 4. We also assessed the predictive value of FeNO to predict “not-well controlled” asthma, which was poor(AUC=0.45, p=0.75)(data not shown). PAQLQ had higher agreement with GINA for the patients > 12 years old than those younger than 12 yeras old(κ=0.326, p<0.001 and κ=0.151, p=0.014, respectively). PAQLQ had stronger correlation with ACT(r=0.789, p<0.001) than PACT(r=0.658, p<0.001).