Different Impacts of Traffic-Related Air Pollution on Early-Onset and Late-Onset Asthma

Figures & data

Table 1 Characteristics of Patients with Early- or Late-Onset Asthma

Characteristics	Number of Patients (N=675)	EOA (N=260)	LOA (N=415)	p-Value
Age (years)	56.5±17.9	42.7±17.1	65.1±12.0	<0.05
Males	322 (47.7)	119 (45.8)	203 (48.9)	0.425
BMI (kg/m^2)	24.64±6.09	24.09±7.10	24.99±5.33	0.061
Smoking status
Current smoker	87 (12.9)	39 (15.0)	48 (11.6)	<0.05
Ex-smoker	154 (22.8)	40 (15.4)	114 (27.4)
Non-smoking	434 (64.3)	181 (69.6)	253 (61)
Age of onset (years)	44.8±22.9	20.3±12.1	60.2±12.2	<0.05
Asthma duration (years)	11.7±16.7	22.5±21.3	4.9±7.2	<0.05
Parental asthma history
Yes	196 (29.0)	95 (36.5)	101 (24.3)	<0.05
No	479 (71.0)	165 (63.5)	314 (75.7)
Inflammatory biomarkers
IgE level (KU/L)	254.56±443.77	299.86±416.49	226.17±458.25	<0.05
Eosinophils (%)	1.89±2.66	2.01±2.89	1.81±2.51	0.693
Eosinophil count (cells/μL)	164.78±216.70	180.19±237.93	155.12±201.97	0.143
ECP (µg/L)	11.37±16.90	15.86±20.57	8.56±13.39	<0.05
Allergic sensitization status
Yes	316 (46.8)	157 (60.4)	159 (38.3)	<0.05
No	359 (53.2)	103 (39.6)	256 (61.7)
History of exacerbation in previous year
Yes	85 (12.6)	38 (14.6)	47 (11.3)	0.506
No	590 (87.4)	222 (85.4)	368 (88.7)
ACT	21.06±4.04	20.52±4.18	21.38±3.93	<0.05
Lung function
FVC (L)	2.40±1.16	2.78±1.39	2.16±0.91	<0.05
FVC (%)	75.62±26.45	77.09±30.10	74.70±23.87	0.253
FEV1 (L/s)	1.85±1.01	2.21±1.25	1.62±0.74	<0.05
FEV1 (%)	70.67±27.20	72.12±29.97	69.76±25.31	0.273
FEV1/FVC (%)	70.40±23.25	70.45±26.56	70.37±20.95	0.965
Post-BD FEV1 (% change)	5.95±11.84	5.65±12.64	6.13±11.32	0.608
Mean exposure to PM10 (μg/m^3)
1-month	27.56±7.90	27.60±7.47	27.54±8.16	0.923
6-month	28.80±7.00	29.38±7.04	28.44±6.96	0.089
12-month	30.36±6.69	30.63±6.48	30.19±6.82	0.406
Mean exposure to PM2.5 (μg/m^3)
1-month	15.14±4.11	15.16±4.06	15.13±4.15	0.926
6-month	16.05±3.35	16.27±3.35	15.90±3.34	0.162
12-month	16.85±2.84	16.88±2.74	16.83±2.90	0.823
Mean exposure to NO2 (ppb)
1-month	15.20±4.63	15.61±4.77	14.95±4.54	0.071
6-month	15.84± 4.34	16.37±4.26	15.51±4.36	<0.05
12-month	16.24± 4.01	16.57±3.88	16.04±4.09	0.095
Mean exposure to O3 (ppb)
1-month	29.57±7.44	28.93±7.32	29.98±7.50	0.073
6-month	28.91±3.58	28.96±3.26	28.89±3.77	0.804
12-month	29.31±3.14	29.15±2.85	29.42±3.31	0.651

Note: Data are presented as mean ± SD or number (percentage).

Abbreviations: EOA, early-onset asthma; LOA, late-onset asthma; BMI, body mass index; IgE, immunoglobulin E; ECP, eosinophil cationic protein; ACT, Asthma Control Test; FVC, forced vital capacity; FEV₁, forced expiratory volume in 1 s; BD, bronchodilator; PM₁₀, particles with an aerodynamic diameter of 10 μm or less; PM_2.5, particles with an aerodynamic diameter of 2.5 μm or less; NO₂, nitrogen dioxide; O₃, ozone.

Figure 1 Associations of (A) PM₁₀, (B) PM_2.5, (C) NO₂, and (D) O₃ with asthma features in patients with EOA and LOA. *p<0.05.

Abbreviations: PM, particulate matter; NO₂, nitrogen dioxide; O₃, ozone; EOA, early-onset asthma; LOA, late-onset asthma.

Figure 2 Associations of PM₁₀ with asthma features in patients with (A) EOA and atopy, (B) EOA and non-atopy, (C) LOA and atopy, and (D) LOA and non-atopy. *p<0.05.

Abbreviations: PM, particulate matter; EOA, early-onset asthma; LOA, late-onset asthma.

Figure 3 Associations of PM_2.5 with asthma features in patients with (A) EOA and atopy, (B) EOA and non-atopy, (C) LOA and atopy, and (D) LOA and non-atopy. *p<0.05.

Abbreviations: PM, particulate matter; EOA, early-onset asthma; LOA, late-onset asthma.

Figure 4 Associations of NO₂ with asthma features in patients with (A) EOA and atopy, (B) EOA and non-atopy, (C) LOA and atopy, and (D) LOA and non-atopy. *p<0.05.

Abbreviations: NO₂, nitrogen dioxide; EOA, early-onset asthma; LOA, late-onset asthma.

Figure 5 Associations of O₃ with asthma features in patients with (A) EOA and atopy, (B) EOA and non-atopy, (C) LOA and atopy, and (D) LOA and non-atopy. *p<0.05.

Abbreviations: O₃, ozone; EOA, early-onset asthma; LOA, late-onset asthma.