Table 3.

Unadjusted and adjusted correlation of ILD severity with body composition

	Unadjusted analysis				Adjusted for sex, age, weight
	Men		Women
	r	p-value	r	p-value	Coefficient (95% CI)	p-value	R2
SMI, kg/m2
FVC, %-predicted	0.22	0.07	−0.06	0.71	0.012 (0.005 to 0.018)	0.0006	0.75
DLCO, %-predicted	0.39	0.002	0.15	0.40	0.013 (0.006 to 0.021)	0.0009	0.76
CPI	−0.40	0.002	−0.19	0.27	−0.016 (− 0.026 to − 0.007)	0.0001	0.76
Dyspnea (UCSD SOBQ)	− 0.08	0.57	0.29	0.09	−0.004 (− 0.010 to 0.002)	0.19	0.74
Body fat, %
FVC, %-predicted	−0.37	0.002	−0.30	0.04	−0.063 (− 0.105 to − 0.020)	0.004	0.70
DLCO, %-predicted	0.03	0.79	0.12	0.51	0.001 (−0.050 to 0.052)	0.96	0.68
CPI	0.05	0.68	−0.06	0.74	0.025 (−0.036 to 0.087)	0.42	0.69
Dyspnea (UCSD SOBQ)	0.41	0.003	0.28	0.09	0.021 (−0.017 to 0.060)	0.28	0.70

Coefficients are reported per one-unit change for the predictor variables. A positive coefficient indicates an increase in the outcome variable per unit of the predictor variable (e.g., SMI increases by an average of 0.012 kg/m² for every 1% increase of FVC %-predicted)

Abbreviations: CI confidence interval, CPI Composite Physiologic Index, C diffusion capacity of the lung for carbon monoxide, FVC forced vital capacity, r Pearson’s correlation coefficient, R² coefficient of determination (variability in the outcome explained by the model), SMI skeletal muscle index, UCSD SOBQ University of California San Diego Shortness of Breath Questionnaire