Association of Irisin with Fat Mass, Resting Energy Expenditure, and Daily Activity in Conditions of Extreme Body Mass Index

Table 1

Independent effects of body composition and activity markers on variations in irisin plasma levels.

	𝐵 (95% CI)	𝑃 value
Model 1∗
REE (Kcal/d)	0.35 (0.01; 0.005)	0.001
Daily physical activity (units/d)	−0.14 (−0.17; 0.01)	0.088
Corrected 𝑅^2=0.21		<0.001
Model 2∗
REE (Kcal/d)	2.15 (0.06; 0.33)	0.006
Daily physical activity (units/d)	−0.10 (−0.15; 0.03)	0.202
Fat-free mass (Kg)	−1.81 (−9.81; −0.85)	0.020
Corrected 𝑅^2=0.23		<0.001
Model 3∗
REE (Kcal/d)	−0.43 (−0.08; 0.01)	0.060
Daily physical activity (units/d)	−0.12 (−0.16; 0.02)	0.139
Fat mass (Kg)	0.94 (0.74; 2.31)	<0.001
Corrected 𝑅^2=0.28		<0.001
Model 4∗
REE (Kcal/d)	0.09 (−0.32; 0.14)	0.435
Daily physical activity (units/d)	0.07 (−10.17; 9.09)	0.119
Fat mass (Kg)	1.7 (0.6; 2.8)	0.003
Fat-free mass (Kg)	1.3 (−4.8; 7.5)	0.657
Corrected 𝑅^2=0.28		<0.001

∗Adjusted for age and BMI group (0: anorexia nervosa; 1: normal weight; 2: obesity).