Table 1.
Characteristics of studies included in the meta-analysis (n = 63).
| First author, year | Country | Ethnicity | No. of OSAS/control | OSAS patients | Controls | Sample | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Age (years) | BMI (kg/m2) | AHI (events/h) | Age (years) | BMI (kg/m2) | AHI (events/h) | |||||
| ADULTS | ||||||||||
| Vgontzas, 1997 (26) | USA | Mixed | 12/10 | 40.9 ± 2.2 | 40.5 ± 3.2 | 63.7 ± 10.3 | 24.1 ± 0.8 | 24.6 ± 0.7 | 0 ± 0 | Plasma |
| Huiguo, 2000 (27) | China | Asian | 22/16 | 47.4 ± 13.6 | 27.6 ± 3.3 | 44.0 ± 21.0 | 47.6 ± 14.7 | 23.1 ± 3 | 4.29 ± 2.16 | Plasma |
| Roytblat, 2000 (28) | USA | Mixed | 11/12 | 39.5 ± 5.0 | 38.3 ± 8.0 | ≥5 | 32.8 ± 8.2 | 21.0 ± 5.3 | <5 | Serum |
| Teramoto, 2003 (29) | Japan | Asian | 40/40 | Adult | NR | ≥5 | Adult | NR | <5 | Plasma |
| Yokoe, 2003 (30) | Japan | Asian | 26/14 | 52.5 ± 5.7 | 28.4 ± 3.5 | 33.7 ± 24.5 | 48.8 ± 3.0 | 27.6 ± 0.5 | 2.8 ± 0.2 | Serum |
| Ciftci, 2004 (12) | Turkey | Caucasian | 43/22 | 49.6 ± 9.1 | 31.9 ± 4.1 | 33.2 ± 5.0 | 47.2 ± 10.3 | 31.03 ± 3.1 | 1.55 ± 0.96 | Serum |
| Imagawa, 2004 (31) | Japan | Asian | 117/46 | Adult | 27.7 ± 4.4 | ≥5 | Adult | 22.9 ± 2.9 | <5 | Serum |
| Ryan, 2006 (32) | Ireland | Caucasian | 66/30 | 42.5 ± 8.5 | 32.5 ± 4.8 | 35.0 ± 13.9 | 41 ± 8 | 30.7 ± 3.1 | 1.2 ± 1.0 | Serum |
| de la Peña Bravo, 2007 (34) | USA | Mixed | 50/20 | 51.7 ± 1.9 | 33.2 ± 1.7 | 51.3 ± 4.2 | 47.4 ± 1.2 | 28.4 ± 0.6 | 2.5 ± 0.5 | Serum |
| Harsch, 2007 ((35) | Germany | Caucasian | 19/20 | 59.0 ± 2.0 | 34.4 ± 1.4 | ≥5 | 53.0 ± 2.0 | 31.6 ± 1.0 | <5 | Plasma |
| Arias, 2008 (36) | Spain | Caucasian | 30/15 | 52.0 ± 13.0 | 30.5 ± 4.0 | 43.8 ± 27.0 | 48.0 ± 10.0 | 28.7 ± 4.7 | 3.7 ± 3.3 | Plasma |
| Constantinidis, 2008 (37) | Greece | Caucasian | 24/27 | 45.1 ± 8.2 | ≥25 | 23.3 ± 3.6 | 45.1 ± 8.2 | ≥25 | 3.5 ± 0.4 | Serum |
| Li, 2008 (40) | Thailand | Asian | 68/22 | 45.5 ± 11.3 | 27.7 ± 4.6 | 31.4 ± 28.6 | 43 ± 9 | 23.3 ± 2.0 | 2.9 ± 1.3 | Serum |
| Takahashi, 2008 (41) | Japan | Asian | 41/12 | 49.8 ± 10 | 29.4 ± 4.2 | ≥5 | 46.7 ± 11.2 | 25.7 ± 4.1 | <5 | Plasma |
| Tomiyama, 2008 (42) | Japan | Asian | 50/15 | 51.4 ± 13.0 | 26.9 ± 4.2 | 42.7 ± 27.9 | 53.0 ± 10.0 | 24.3 ± 2.5 | <5 | Plasma |
| Vgontzas, 2008 (43) | Greece | Caucasian | 16/28 | 48.1 ± 5.6 | 37.5 ± 4.7 | 53.3 ± 7.0 | 48.1 ± 10.6 | 30.8 ± 5.2 | 2.1 ± 0.8 | Plasma |
| Yamamoto, 2008 (44) | Japan | Asian | 31/10 | 49.0 ± 2.0 | 28.0 ± 1.0 | ≥5 | 46.0 ± 6.0 | 27.0 ± 2.0 | <5 | Serum |
| Carneiro, 2009 (45) | Brazil | Mixed | 16/13 | 40.1 ± 2.8 | 46.9 ± 2.0 | 65.7 ± 9.9 | 38.8 ± 3.3 | 42.8 ± 1.3 | 3.2 ± 0.5 | Plasma |
| Li, 2009 (46) | China | Asian | 68/22 | 45.3 ± 11.1 | 20.7 ± 10.1 | 38.9 ± 26.5 | 43.0 ± 93.0 | 23.3 ± 2.0 | 2.9 ± 1.3 | Serum |
| Thomopoulos, 2009 (47) | Greece | Caucasian | 62/70 | 48.1 ± 7.6 | 31.9 ± 4.9 | 31.6 ± 2.0 | 48.1 ± 3.9 | 32.1 ± 3.0 | 0.4 ± 4.0 | Serum |
| Sahlman, 2010 (48) | Finland | Caucasian | 84/40 | 50.4 ± 9.3 | 32.5 ± 3.3 | 9.6 ± 2.9 | 45.6 ± 11.5 | 31.5 ± 3.5 | 1.9 ± 1.4 | Plasma |
| Steiropoulos, 2010 (49) | Greece | Caucasian | 38/23 | 45.5 ± 10.5 | 36.4 ± 7.4 | 61.0 ± 27.0 | 43.7 ± 6.7 | 34.5 ± 3.7 | 5.3 ± 3.2 | Serum |
| Ye, 2010 (50) | China | Asian | 127/52 | 45.3 ± 11.4 | 26.2 ± 3.7 | 36.5 ± 25.7 | 45.0 ± 10.0 | 26.0 ± 3.2 | 2.0 ± 1.4 | Serum |
| Liu, 2011(51) | China | Asian | 78/20 | 45.2 ± 7.3 | 27.9 ± 3.1 | 46.3 ± 9.2 | 43.5 ± 8.3 | 26.1 ± 2.4 | <5 | Serum |
| Fornadi, 2012 (52) | Canada | Mixed | 25/75 | 54.0 ± 12.0 | 29.0 ± 5.0 | ≥5 | 50.0 ± 13.0 | 26.0 ± 5.0 | <5 | Serum |
| Medeiros, 2012 (53) | Brazil | Mixed | 50/15 | 62.3 ± 7.8 | 25.5 ± 4.0 | ≥5 | 62.50 ± 8.4 | 25.8 ± 4.0 | <5 | Serum |
| Qian, 2012 (54) | China | Asian | 70/40 | 45.8 ± 8.2 | 28.9 ± 2.3 | ≥5 | 46.3 ± 8.1 | 24.1 ± 2.3 | <5 | Serum |
| Ye, 2012 (55) | China | Asian | 44/20 | 46.43 ± 18.22 | 28.2 ± 5.34 | 40.41 ± 20.68 | 45.80 ± 23.01 | 26.90 ± 4.25 | 2.26 ± 1.30 | Plasma |
| Hargens, 2013 (56) | USA | Mixed | 12/33 | 22.8 ± 0.8 | 32.4 ± 1.0 | 25.4 ± 5.4 | 21.9 ± 0.6 | 29.3 ± 0.5 | 2.1 ± 0.3 | Serum |
| Kurt, 2013 (57) | Turkey | Caucasian | 48/37 | 48.3 ± 12.3 | NR | ≥5 | 43.1 ± 14.1 | NR | <5 | Serum |
| Yang, 2013 (58) | China | Asian | 50/25 | 53.5 ± 6.9 | 27.4 ± 2.9 | 24.5 ± 15.9 | 53.0 ± 7.0 | 26.27 ± 1.9 | 3.0 ± 1.0 | Plasma |
| Ciccone, 2014 (59) | Italy | Caucasian | 80/40 | 52.8 ± 10.6 | 28.6 ± 3.0 | 33.9 ± 21 | 52.3 ± 10.5 | 28.2 ± 2.7 | 2.1 ± 1.1 | Plasma |
| Kritikou, 2014 (61) | Greece | Caucasian | 38/39 | 55.7 ± 6.6 | 28.7 ± 3.3 | 37.5 ± 21.0 | 53.8 ± 6.2 | 27.3 ± 3.5 | 2.3 ± 1.9 | Plasma |
| Unuvar Dogan, 2014 (62) | Turkey | Caucasian | 33/24 | 45.3 ± 8.5 | 31.0 ± 1.7 | 47.2 ± 23.2 | 40.5 ± 9.5 | 30.7 ± 1.5 | 3.6 ± 1.8 | Serum |
| De, 2015 (63) | Italy | Caucasian | 26/24 | 41.8 ± 7.4 | 33.0 ± 5.2 | 26.15 ± 12.1 | 43.7 ± 8.2 | 30.8 ± 4.3 | 1.65 ± 0.9 | Serum |
| Gaines, 2015 (64) | Greece | Caucasian | 82/38 | 54.9 ± 5.8 | 29.2 ± 3.3 | 22.6 ± 15.0 | 54.2 ± 5.8 | 27.6 ± 3.7 | 2.0 ± 15.0 | Plasma |
| Hui, 2015 (65) | China | Asian | 35/20 | 47.6 ± 6.6 | 27.3 ± 4.4 | ≥5 | 25.1 ± 5.3 | 40.5 ± 4.9 | <5 | Serum |
| Ulasli, 2015 (67) | Turkey | Caucasian | 62/20 | 51.7 ± 10.2 | 32.4 ± 5.6 | 26.5 ± 18.5 | 45.3 ± 14 | 30.4 ± 8 | 2.2 ± 0.93 | Serum |
| Thunstrom, 2015 (66) | Sweden | Caucasian | 344/95 | 61.9 ± 9.2 | 28.9 ± 4.0 | 29.7 ± 14.6 | 61.4 ± 9.5 | 25.2 ± 2.5 | 3.1 ± 1.3 | Serum |
| Dogan, 2016 (68) | Turkey | Caucasian | 39/12 | 40.7 ± 10.75 | 29.26 ± 4.12 | ≥5 | 40.0 ± 11.7 | 27.29 ± 2.93 | <5 | Serum |
| Nizam, 2016 (70) | Turkey | Caucasian | 39/13 | 47.3 ± 10.4 | 33.2 ± 56.4 | 45.6 ± 20.7 | 43.23 ± 9.08 | 31.71 ± 4.56 | 2.64 ± 1.82 | Serum |
| Vicente, 2016 (71) | Spain | Caucasian | 89/26 | 45.33 ± 14.81 | 30.03 ± 5.04 | 28 ± 23.70 | 45 ± 11.11 | 28.7 ± 4.37 | 1.9 ± 2.7 | Plasma |
| Hirotsu, 2017 (72) | Brazil | Mixed | 339/682 | 50.8 ± 13.2 | 29.6 ± 5.8 | 19.3 ± 9.44 | 38.2 ± 12.7 | 25.4 ± 3.8 | 2.5 ± 10.4 | Serum |
| Kong, 2017 (73) | China | Asian | 82/30 | 45.6 ± 8.8 | 27.7 ± 4.6 | ≥5 | 45.7 ± 6.6 | 27.6 ± 3.6 | <5 | Serum |
| Thorn, 2017 (74) | UK | Caucasian | 16/14 | 59 ± 13 | 32.7 ± 4.0 | 30 ± 18 | 58 ± 7 | 30.6 ± 2.7 | <5 | Serum |
| Weingarten, 2017 (76) | USA | Mixed | 11/8 | 38.7 ± 10.5 | 47.3 ± 14.8 | 25.1 ± 17.8 | 33.6 ± 5.1 | 25.5 ± 10.9 | 1.8 ± 1.0 | Serum |
| Zhang, 2017 (77) | China | Asian | 50/52 | 79.4 | NR | ≥5 | 77.1 | NR | <5 | Serum |
| Al-Terki, 2018 (78) | USA | Mixed | 52/22 | 40.3 ± 1.6 | 29.5 ± 0.7 | 22.9 ± 17.9 | 39.6 ± 2.2 | 28.5 ± 0.9 | 2.5 ± 1.6 | Plasma |
| Bhatt, 2018 (79) | India | Caucasian | 171/69 | 44.6 ± 9.1 | 33.1 ± 7.6 | ≥5 | 40.0 ± 9.8 | 30.1 ± 8.4 | <5 | Serum |
| Bozic, 2018 (80) | Croatia | Caucasian | 50/25 | 53.0 ± 11.9 | 28.9 ± 2.7 | 35.0 ± 11.0 | 52.5 ± 10.2 | 27.8 ± 2.2 | <5 | Plasma |
| Kong, 2018 (81) | China | Asian | 50/40 | 54.34 ± 14.38 | 26.86 ± 3.12 | 37.34 ± 19.02 | 50.42 ± 8.35 | 22.26 ± 3.54 | 3.31 ± 1.09 | Serum |
| Lu, 2018 (82) | China | Asian | 35/22 | 48.63 ± 1.80 | 28.21 ± 0.51 | ≥5 | 49.04 ± 2.27 | 26.01 ± 0.65 | <5 | Serum |
| Motamedi, 2018 (83) | USA | Mixed | 50/24 | 34.9 ± 8.0 | 30.8 ± 4.2 | 18.4 ± 13.1 | 30.9 ± 7.77 | 28.6 ± 3.81 | 2.12 ± 1.3 | Plasma |
| Sundbom, 2018 (84) | Sweden | Caucasian | 109/224 | 55.6 ± 8.8 | 28.2 ± 4.8 | 25.4 ± 2.1 | 47.7 ± 11.3 | 25.4 ± 4.1 | 3.7 ± 0.6 | Plasma |
| Bhatt, 2019 (85) | India | Caucasian | 47/25 | 44.2 ± 9.1 | 32.5 ± 6.9 | 13.5 ± 6.4 | 28.5 ± 8.6 | 41 ± 8.5 | 2.3 ± 1.1 | Serum |
| Tang, 2019 (86) | China | Asian | 120/127 | 48.88 ± 9.76 | 26.86 ± 3.12 | 39.00 ± 18.38 | 47.37 ± 9.12 | 22.46 ± 3.29 | 3.31 ± 1.09 | Serum |
| Galati, 2020 (87) | Italy | Caucasian | 45/30 | 53.9 ± 11.6 | 28 ± 2.2 | ≥5 | 55 ± 5.8 | 26.3 ± 1.8 | <5 | Serum |
| CHILDREN | ||||||||||
| Tam, 2006 (33) | Australia | Mixed | 44/69 | 7.3 ± 3.7 | 19.4 ± 5.5 | 5.3 ± 6.5 | 7.6 ± 4.0 | 17.9 ± 3.9 | 0 ± 0 | Serum |
| Gozal, 2008 (38) | USA | Mixed | 20/20 | 6.5 ± 0.6 | 17.3 ± 0.6 | ≥5 | 6.4 ± 0.7 | 17.1 ± 0.5 | 0 ± 0 | Plasma |
| Li, 2008 (39) | China | Asian | 47/95 | 11.1 ± 1.27 | NR | 14.1 ± 8.0 | 10.7 ± 1.3 | NR | 0.7 ± 0.6 | Serum |
| Gileles-Hillel, 2014 (60) | Spain | Caucasian | 75/129 | 10.4 ± 2.8 | 28.0 ± 4.6 | 14.2 ± 9.0 | 11.0 ± 2.4 | 27.9 ± 4.1 | 0.6 ± 0.6 | Plasma |
| Huang, 2016 (69) | Taiwan | Asian | 47/32 | 7.84 ± 0.56 | 16.95 ± 0.47 | 9.13 ± 1.67 | 7.02 ± 0.65 | 16.55 ± 0.58 | 0.37 ± 0.06 | Plasma |
| Van Eyck, 2017 (75) | Belgium | Caucasian | 53/111 | 11.5 ± 2.75 | NR | 20.53 ± 15.98 | 12 ± 2.75 | NR | 0.72 ± 0.47 | Serum |
NR, not reported; OSAS, obstructive sleep apnea syndrome; AHI, apnea–hypopnea index; BMI, body mass index.