Residential Proximity to Freeways is Associated with Uncontrolled Asthma in Inner-City Hispanic Children and Adolescents

Table 1

Characteristics of patients described by asthma control during year one participation in Breathmobile program.

		Asthma control during year 1(a)
	Overall N = 756	Well controlled N = 402	Not well controlled N = 354	P-value(a)
Age (years; mean [SD])	8.5 yrs [3.2]	8.3 yrs [3.1]	8.7 yrs [3.3]	P  =  .13
Female sex	40.6%	40.4%	40.8%	P  =  .91
Baseline Severity:
Intermittent	21.7%	26.4%	16.4%	P  <  .01
Mild persistent	24.9%	27.1%	22.3%
Moderate persistent	28.4%	27.4%	29.7%
Severe persistent	25.0%	19.2%	31.6%
Baseline morbidity (past year):
Asthma Attacks (two or more)	14.9%	16.4%	13.3%	P  =  .23
ED visits (one or more)	26.7%	26.4%	27.1%	P  =  .82
Hospitalizations (one or more)	7.5%	6.2%	9.0%	P  =  .14
School absenteeism (≥5 d)	22.1%	18.9%	25.7%	P  =  .03
Distance from freeway(c):
Mean miles [SD]	1.0 mi [0.83]	1.1 [0.88]	1.0 mi [0.76]	P  =  .29
Range	(0.02–3.78)	(0.02–3.78)	(0.02–3.51)
<1 mile	55.7%	56.5%	54.8%	P  =  .03
1-<2 miles	29.8%	27.1%	32.8%
2-<3 miles	11.0%	11.2%	10.7%
≥3 miles	3.6%	5.2%	1.7%

(a)Patient’s asthma control during year 1 Breathmobile program participation: well controlled (asthma control maintained at 80% or more of follow-up visits during year 1) and not well controlled (asthma control maintained at fewer than 80% of follow-up visits during year 1). The majority of patients in this category (68%) maintained asthma control at 50%–79.9% of follow-up visits).
(b)P-value: Significance asthma control group differences in distributions based on independent t-test (continuous factors) and chi-square test (categorical factors).
(c)Point of reference: Patient’s home.