Relationship between circulating irisin levels and overweight/obesity: A meta-analysis

Table 1 Characteristics of included studies

Ref.	Country	Blood sample	Participants’ age, years (case-control)	Cases/controls, n	Irisin assay	BMI (kg/m2) (case-control)	ELISA kit
Moreno-Navarrete et al[7], 2013	Spain	Plasma	52.41 ± 10.99-47.28 ± 10.15	51/18	ELISA	28.98 ± 3.17-23.33 ± 1.2	SK00170-01; Aviscera Bioscience Inc, Santa Clara, California
Stengel et al[13], 2013	Germany	Plasma	47.17 ± 11.91-48.5 ± 12.16	24/8	ELISA	50.63 ± 15.27-22.6 ± 2.55	Phoenix Pharmaceuticals, Inc., Burlingame, CA, United States
Crujeiras et al[12], 2014	Spain	Plasma	49.4 ± 9.4-35.71 ± 8.8	94/48	ELISA	35.6 ± 4.5-22.9 ± 2.2	Mercodia, AB (Uppsala, Sweden)
Hou et al[18], 2015	China	Serum	33 ± 9-31 ± 7	41/40	ELISA	30.8 ± 3.8-21.3 ± 1.8	Phoenix Pharmaceuticals, Inc., Burlingame, CA, United States
Palacios-González et al[20], 2015	Mexico	Serum	9.07 ± 0.88-9.0 ± 0.86	60/25	ELISA	-0.25 ± 0.67-2.11 ± 0.771	CUSA-BIO BIOTECH
Viitasalo et al[26], 2016[26]	Finland	Plasma	7.71 ± 0.4-7.6 ± 0.4	55/388	ELISA	20.21 ± 1.52-15.5 ± 1.3	Phoenix Pharmaceuticals, Inc., Burlingame, CA, United States
Belviranli et al[17], 2016	Turkey	Plasma	34.40 ± 10.60-28.70 ± 6.82	10/10	ELISA	32.65 ± 3.04-23.00 ± 2.23	BioVendor, Czech Republic
Chen et al[14], 2016	China	Serum	34.4 ± 7.6-32.8 ± 7.8	30/20	ELISA	33.3 ± 4.2-21.1 ± 2.0	PHOENIX PHARMACEUTICAL
Fagundo et al[15], 2016	Spain	Plasma	44.49 ± 11.50-29.04 ± 6.22	65/49	ELISA	42.83 ± 6.63-21.61 ± 1.54	EK-067-52; Phoenix Pharmaceuticals, INC, CA
Mehrabian et al[27], 2016	Iran	Serum	28.76 ± 4.67-29.23 ± 4.50	38/26	ELISA	22.26 ± 1.23-20.88 ± 1.28	Biovendor, Laboratory Medicine, Modrice Czech Republic
Rizk et al[28], 2016	Egypt	Serum	45.45 ± 8.30-44.25 ± 10.46	20/20	ELISA	32.54 ± 1.80-22.85 ± 1.68	BioVendor, Bmo, Czechrepublic (cat. No. RAG018R)
Shoukry et al[29], 2016	Egypt	Serum	47.06 ± 4.76-45.12 ± 4.72	119/31	ELISA	34.72 ± 5.68-23.27 ± 0.50	BioVision, Milpitas, CA
Elizondo-Montemayor et al[21], 2017	Mexico	Plasma	8.0 (6–11)-8.5 (6-12)	5/5	ELISA	98 (98-99)-66 (35-73)	Phoenix Pharmaceuticals, Inc., Burlingame, CA, United States
Jang et al[30], 2017	South Korea	Serum	13.7 ± 0.7-13.5 ± 0.5	248/370	ELISA	31.4 ± 3.8-19.4 ± 1.5	Cat#EK-067-52; Phoenix, Pharmaceuticals, Belmont, CA
Liu et al[19], 2017	China	Serum	35.20 ± 6.51-35.01 ± 7.09	51/75	ELISA	27.80 ± 3.04-22.62 ± 2.52-	Bio Vision, Milpitas, CA95035, United States
Nigro et al[22], 2017	Italy	Serum	9.7 ± 2.7-8 ± 2.4	27/13	ELISA	2.7 ± 0.5-—0.46 ± 1.2	Phoenix Pharmaceuticals, Belmont, CA, United States
Tibana et al[16], 2017	Brazil	Serum	66.5 ± 5.0-68.0 ± 6.2	26/23	ELISA	30.9 ± 3.1-24.3 ± 3.6	MyBioSource Inc., San Diego, CA, United States
Sahin-Efe et al[31], 2018	United States	Serum	69.4 ± 8.6-69.5 ± 9.2	41/73	ELISA	30.5 (29.6–31.5)-24.0 (23.3–24.7)	CAT#EK-067-52; Phoenix Pharmaceuticals, Burlingame, CA

¹BMI z-score. Data are presented as the mean ± SD for continuous parametric variables or median (interquartile range) for continuous nonparametric variables. ELISA: Enzyme-linked immunosorbent assay.