Table 3.

Features of participants in the Severe Asthma Research Program (SARP)

Characteristics	Non-severe Asthma (n = 703)	Severe Asthma (n = 580)	P Value*
Age — yr	37 ± 14	47 ± 13	<0.0001
Female — %	67	66	0.6
Ancestry — %
European ancestry	65	66	0.7
African ancestry	26	26	0.9
Body mass index — kg/m2	29.8 ± 7.9	32.5 ± 8.7	<0.0001
Blood pressure — mm Hg
Systolic	122 ± 14	128 ± 15	<.0001
Diastolic	75 ± 10	78 ± 10	<0.0001
Hemoglobin — g/dL	14.1 ± 2.5	14.7 ± 8.1	0.2
Hematocrit — %	41.1 ± 4.1	41.8 ± 5.5	0.08
Lung functions
Forced expiratory volume in 1 second — % predicted	82 ± 17	64 ± 21	<0.0001
Forced vital capacity —% predicted	92 ± 16	78 ± 18	<0.0001
FEV1/FVC	0.74 ± 0.10	0.65 ± 0.12	<0.0001
Asthma control test†	19.4 ± 4.0	15.3 ± 4.8	<0.0001
White blood cells — x109/liter	6.8 ± 2.1	8.0 ± 2.9	<0.0001
Neutrophils	3.9 ± 1.7	5.0 ± 2.6	<0.0001
Eosinophils	0.25 ± 0.21	0.29 ± 0.27	0.01
IgE — lU/ml	337 ± 799	331 ± 547	0.8
Glutathione peroxidase — U/ml	0.085 ± 0.021	0.091 ± 0.025	0.05
Superoxide dismutase — U/ml	18.6 ± 10.9	19.7 ± 10.4	0.13
Fractional exhaled nitric oxide — ppb	37 ± 34	35 ± 36	0.5
Exacerbations in prior year	0.61 ± 1.19	2.37 ± 2.82	<0.0001
Exacerbations in one-year follow-up	0.36 ± 0.88	1.38 ± 1.98	<0.0001
mtDNA-CN	92.0 ± 70.5	80.0 ± 64.2	0.001
Unadjusted mtDNA-CN residuals	0.080 ± 1.037	-0.097 ± 0.945	0.001
Adjusted mtDNA-CN	0.004 ± 1.038	-0.005 ± 0.953	0.8

Mean ± SD;

^*P value for non-severe asthmatics vs. severe asthmatics.

^†Scores of 19 or higher are well controlled.