One hundred-fifty asthmatic children were enrolled with the mean (SD) age of 11.82 (3.38) years. Ninety-four children (62.7%) were males, 110 children (73.3%) were allergic asthma, and 147 (98.7%) children had allergic rhinitis. Only 23 children (15.3%) were obese. The mean (SD) PACT and score PAQLQ were 23.48 (2.51), 6.55 (0.44), respectively. Seventy children (46.7%) met the criteria for dyslipidemia. Of 70 children with dyslipidemia, 15 children (21.4%) were obese, 44 children (62.85%) had high LDL-C, 39 children (55.71%) had high TC, 35 children (50%) had high non-HDL-C, 24 children (34.28%) had high TG, and 12 children (17.14%) had low HDL-C. The baseline characteristic of the enrolled children was demonstrated in Table 1.
Correlations of serum cholesterol, triglyceride, LDL, HDL, and spirometry
There were no significant correlations between TG, LDL-C, non-HDL-C, and CRP with spirometry parameters. However, significant correlations between HDL-C, TC and TG/HDL-C ration with % FEV1/FVC ratio were observed (r=0.215, p=0.008, r=0.183, p=0.025, and r=-0.17, p=0.038, respectively) (Figure 1A-C).
Correlations between CRP and Lipid Profile
A Pearson correlation analysis was performed to analyze the correlation between CRP and lipid profile. HDL-C was significantly negative correlated with CRP value (r = -0.236, p = 0.004) (Figure 1D). However, there were no significant correlations between the level of CRP and other lipid profiles.
Comparison of spirometry between dyslipidemia and non-dyslipidemia children
There were no significant differences in the baseline characteristics between children with or without dyslipidemia (Table 2). There were no significant differences in spirometry parameters between subjects with dyslipidemia and those with normal lipid profiles (Table 2).
Comparison of spirometry parameters between obese and non-obese children
Obese children had significantly higher FVC % predicted, FEV1% predicted but lower % FEV1/FVC. Obese children also had significantly more %D of FEV1 and FVC. Obese children also had a significantly higher CRP level than those having a normal weight. No significant differences in ACT/PACT and PAQLQ scores were observed. Interestingly, only the TG level was significantly different between obese asthmatic children and non-obese asthmatic children (Table 3).
Subgroup analysis comparison in lung function parameters between children with or without dyslipidemia and obesity or non-obesity
Comparison among children with obesity and dyslipidemia, obesity and non-dyslipidemia, dyslipidemia and non-obesity, and non-dyslipidemia and non-obesity demonstrated that FVC % predicted and FVC %D were significant differences among groups. The obesity with dyslipidemia and non-dyslipidemia groups had a significantly higher value of FVC %predicted and FEV1%predicted than those of the non-obesity group. There were no significant differences in FOT parameters among these four groups. Further analysis of TG/HDL-C ratio abnormality(TG/HDL-C > 2.5) and obesity in children demonstrated that FVC % predicted, FVC %D, % FEV1/FVC were significant differences among groups. Children who had abnormal TG/HDL-C ratio and non-obesity had the lowest % FEV1/FVC (Table 4).
Comparison of lipid profiles between children with airflow obstruction and without airflow obstruction
Baseline characteristics and blood lipids of children who had airflow obstruction (% FEV1/FVC ratio < 90) and children with no airflow obstruction (% FEV1/FVC ratio > 90) were compared. Children who had airflow obstruction had significantly higher TG, TG/HDL-C, LDL-C/HDL-C but lower HDL-C. However, children with airflow obstruction had significantly higher body weight, BMI, BMI z-score, and more obesity than those with no airflow obstruction (Table 5). Multiple logistic regression analysis demonstrated only TG/HDL-C ratio was associated with % FEV1/FVC ratio < 90, odd ratio 2.78; 95% confident interval (CI) 1.5-5.15, p =0.001. The model was adjusted for age, body weight, height, BMI, obesity status, and blood lipid parameters.