RNA-sequencing across three matched tissues reveals shared and tissue-specific gene expression and pathway signatures of COPD

Table 1 Models for expression association with outcomes of interest

Phenotype category	Variable of interest	Model
Lung function	COPD case-control	EXP ~ COPD + age + sex + race + pack-years + smoking + RIN + SVs
	FEV1% predicted	EXP ~ FEV1.PP + age + sex + race + pack-years + smoking + RIN + SVs
	FEV1/FVC	EXP ~ FEV1FVC + age + sex + race + pack-years + smoking + RIN + SVs
Smoking	pack-years	EXP ~ pack-years + age + sex + race + RIN + SVs
Smoking	Smoking status	EXP ~ smoking + age + sex + race + RIN + SVs
Emphysema	pctEmph	EXP ~ pctEmph + age + sex + race + BMI + pack-years + smoking + RIN + SVs
	perc15	EXP ~ perc15 + age + sex + race + BMI + pack-years + smoking + RIN + SVs
	adj_density	EXP ~ adj_density + age + sex + race + BMI + pack-years + smoking + RIN + SVs
Airway disease	Pi10	EXP ~ Pi10 + age + sex + race + pack-years + smoking + RIN + SVs
	AWT	EXP ~ AWT + age + sex + race + pack-years + smoking + RIN + SVs
	WallAreaPct	EXP ~ WallAreaPct + age + sex + race + pack-years + smoking + RIN + SVs
Models for peripheral blood also included: WBC, and the percentages of neutrophils, lymphocytes, monocytes and eosinophils
smoking (ordinal variable): 0 non-smoker, 1 former smoker, 2 current smoker

Abbreviations: SVs = surrogate variables; FEV1 = forced expiratory volume in 1 s; FVC = forced vital capacity; pctEmph = % emphysema; perc15 = 15th percentile of lung density histogram; adj_density = adjusted lung density, sponge model adjustment; Pi10 = SRWA-Pi10 = square root wall area of a hypothetical airway with 10 mm internal perimeter; AWT = airway wall thickness; WallAreaPct = wall area percent; EXP = gene expression values; WBC = white blood cell count

ISSN: 1465-993X