Main characteristics of studies included in the meta-analysis
| Source | Region | Study design | Participants (n) | Age (years) | MetS measures | Prevalence of MetS, % (n) | NOS | |||||
| IBD | UC | CD | IBD | UC | CD | Non-IBD | ||||||
| Nagahori et al8 | Japan | Prospective cross-sectional cohort | 102 | 74 | 28 | UC: 43.6±13.5 CD: 31.5±8.1 | Modified National Cholesterol Education Program ATP-III | 18.6 (19/102) | 23.0 (17/74) | 7.1 (2/28) | NA | 8 |
| Dragasevic et al6 | Serbia | Prospective cross-sectional cohort | 104 | 54 | 50 | UC: 43.5 (20–78) CD: 35 (19–72) | International Diabetes Federation and ATP-III | 32.7 (34/104) | 29.6 (16/54) | 36.0 (18/50) | 13.3 (6/45) | 7 |
| Carr et al17 | USA | Retrospective cohort | 84 | 24 | 60 | 52.4±14.5 | ATP-III | 23 (19/84) | 29 (7/24) | 20 (12/60) | NA | 6 |
| Fitzmorris et al18 | USA | Retrospective cohort | – | – | 868 | 40.4 | International Diabetes Federation definition | – | – | 4.3 (37/868) | NA | 7 |
| Jovanovic et al19 | Serbia | Prospective cross-sectional cohort | – | 89 | – | 50 (21–80) | ATP-III | – | 81 (72/89) | – | NA | 3 |
| Yorulmaz et al20 | Turkey | Prospective cross-sectional cohort | 177 | 115 | 62 | UC: 43.9±13.6 CD: 36.7±13.9 | International Diabetes Federation | 25.4 (45/177) | 29.5 (34/115) | 17.7 (11/62) | NA | 4 |
| Kang et al21 | Korea | Retrospective cohort | 443 | 169 | 274 | 35 (26.0–49.5) | ATP-III | 10.6 (47/443) | NA | 7 | ||
| Arieira et al23 | Portugal | Prospective cross-sectional cohort | 161 | 60 | 101 | 40.6±12.8 | American Heart Association | 13.0 (21/161) | NA | 5 | ||
| Magrì et al22 | Italy | Prospective cohort | 178 | 95 | 83 | 49.7 | ATP-III | 19.1 (34/178) | NA | 8 | ||
| Sartini et al24 | Italy | Retrospective cohort | 78 | 36 | 42 | 51.2±11.8 | ATP-III | 23.1 (18/78) | NA | 7 | ||
| Sourianarayanane et al25 | USA | Retrospective cohort | 217 | 107 | 110 | 42±14.1 | ATP-III | 16.6 (36/217) | NA | 7 | ||
ATP-III, Adult Treatment Panel III; CD, Crohn’s disease; IBD, inflammatory bowel disease; MetS, metabolic syndrome; NA, not available; NOS, Newcastle-Ottawa Scale; UC, ulcerative colitis.