TABLE 2.

Stratified analysis of FTO genotype and weight-loss according to study characteristics¹

			TA vs. TT				AA vs. TT
Subgroups	Sample size, n	Studies, n	WMD	95% CI	I2 value	P between groups	WMD	95% CI	I2 value	P between groups
Mean age						0.88				0.95
<50	966	4	−0.21	(−0.73, 0.31)	0.0		−0.42	(−1.12, 0.28)	3.2
≥50	5985	6	−0.17	(−0.48, 0.15)	0.0		−0.44	(−0.85, −0.04)	1.4
Mean BMI at baseline						0.61				0.08
<35	2452	7	−0.25	(−0.64, 0.14)	0.0		−0.79	(−1.33, −0.26)	0.0
≥35	4499	3	−0.11	(−0.48, 0.26)	0.0		−0.17	(−0.63, 0.30)	0.0
Duration						0.51				0.74
<1 y	1204	4	−0.07	(−0.49, 0.35)	0.0		−0.53	(−1.18, 0.12)	0.0
≥1 y	5747	6	−0.25	(−0.60, 0.09)	0.0		−0.40	(−0.82, 0.02)	25.1
Intervention						0.12				0.11
Diet intervention only	2345	6	−0.40	(−0.79, −0.01)	0.0		−0.72	(−1.21, −0.23)	0.0
Other2	4606	4	0.02	(−0.35, 0.39)	0.0		−0.15	(−0.65, 0.49)	0.0
Sex						0.28				0.61
Mixed	6438	7	−0.24	(−0.53, 0.05)	0.0		−0.46	(−0.83, −0.10)	0.0
Female	513	3	0.17	(−0.52, 0.86)	0.0		−0.09	(−1.48, 1.30)	15.5
Region						0.40				0.38
America	4593	3	−0.07	(−0.51, 0.37)	0.0		−0.22	(−0.75, 0.32)	0.0
Europe	2154	6	−0.34	(−0.72, 0.03)	0.0		−0.66	(−1.14, −0.18)	0.0
Asia	204	1	0.20	(−0.60, 1.00)	NA		0.30	(−0.79, −0.09)	NA
Adjusted for baseline BMI or body weight						0.66				0.19
Yes	2761	6	−0.26	(−0.60, 0.08)	0.0		−0.70	(−1.16, −0.23)	0.0
No	4190	4	−0.04	(−0.51, 0.43)	0.0		−0.09	(−0.63, 0.46)	0.0

¹Differences in weight loss after intervention between FTO genotypes across studies were pooled with the use of fixed-effect models. The heterogeneity between studies for each group was tested by I². P values between groups were tested with the use of Cochran’s Q test. FTO, fat mass and obesity–associated; NA, not available; WMD, weighted mean difference.

²Includes studies with exercise interventions, both exercise and diet interventions, or nutritional education.