Characteristics of included studies which conducted a comparison of carotid-intima media thickness (CIMT) means between those with NAFLD and those without
| Name, year | Study region | Study population | Study size | n (%) NAFLD | Age (NAFLD+ vs NAFLD−) | % male (NAFLD+ vs NAFLD−) | NAFLD assessment | Outcome assessment | Confounder adjustment | NOS (max=9) |
| Oni et al22 2019 | North America | Population based | 4123 | 729 (17.7) | 61 vs 63 | 47.0 vs 44.0 | CT, LS ratio <1 | Ultrasound, mean IMT (L&R) | – | 7 |
| Mohammadzadeh et al44 2019 | Iran | Hospital based | 300 | 150 (50.0) | 49.9 vs 52.5 | 65.3 vs 57.3 | Ultrasound | Ultrasound, mean IMT (L&R) | – | 6 |
| Yi et al45 2018 | Asia | Outpatient clinic | 1981 | 1888 (95.3) | 45.9 vs 44.8 | 63.4 vs 40.1 | Ultrasound | Ultrasound, mean of max IMT (L&R) | – | 6 |
| Kim et al30 2018 | Asia | Population (health screen) | 819 | 330 (40.3) | 53.4 vs 53.1 | 64.2 vs 41.5 | Ultrasound | Ultrasound, mean IMT (L&R) | – | 6 |
| Vanjiappan et al46 2018 | Asia | Hospital based, patients with T2DM | 124 | 73 (58.9) | Overall=53.8 | Overall=54.0 | Ultrasound | Ultrasound, mean of max IMT (L&R) | – | 6 |
| Gummesson et al47 2018 | Europe | Population based | 1015 | 106 (10.4) | 58.3 vs 57.5 | 71.7 vs 52.5 | CT, liver HU <40 | Ultrasound, mean IMT | – | 7 |
| Cetindağlı et al48 2017 | Turkey | Outpatient clinic | 120 | 93 (77.5) | 34.5 vs 33.8 | 100 vs 100 | Ultrasound and biopsy | Ultrasound, mean IMT (6 measurements) | Age/sex-matched controls | 7 |
| Guo et al33 2017 | Asia | Hospital based, patients with T2DM | 8571 | 4340 (50.6) | 57.4 vs 61.9 | 54.6 vs 55.9 | Ultrasound | Ultrasound, mean IMT (6 measurements) | Age | 7 |
| Hong et al35 2016 | Asia | Population (health screen) | 955 | 342 (35.8) | 53 vs 51 (median) | 48.8 vs 42.1 | Ultrasound | Ultrasound, mean IMT (99 computer points) | – | 7 |
| Zhang et al49 2016 | Asia | Outpatient clinic, patients with T1DM | 722 | 123 (17.0) | 47.4 vs 46.0 | 52.8 vs 51.1 | Ultrasound | Ultrasound, mean IMT (6 measurements) | Age, sex, BMI, WC, SBP, DBP, total cholesterol, TAG, LDL, HDL, MetS, ALT, AST, GGT, hsCRP, medications | 8 |
| Ozturk et al50 2015 | Turkey | Outpatient clinic, MetS(−) | 82 | 41 (50.0) | 32.8 vs 31.8 | 100 vs 100 | Biopsy | Ultrasound, mean IMT (L&R) | – | 6 |
| Asakawa et al55 2014 | Asia | Population (health screen) | 76 | 24 (31.6) | 61.5 vs 61.0 (median) | 91.7 vs 75.0 | Ultrasound | Ultrasound, max IMT | – | 6 |
| Ayaz et al54 2014 | Turkey | Outpatient clinic | 90 | 60 (66.7) | 44.5 vs 39.5 (median) | 36.7 vs 26.7 | Ultrasound | Ultrasound, mean IMT (8 measurements) | – | 6 |
| Kim et al53 2014 | Asia | Population (health screen), MetS(−) | 1285 | 180 (14.0) | 55.7 vs 55.7 | 58.0 vs 36.0 | CT, liver minus spleen <5 | Ultrasound, mean IMT (4 measurements) | – | 7 |
| Kim et al52 2014 | Asia | Hospital based, patients with T2DM | 1211 | 747 (61.7) | 56.7 vs 55.6 | 51.0 vs 41.8 | Ultrasound | Ultrasound, mean IMT (6 measurements) | – | 6 |
| Nahandi et al51 2014 | Iran | Hospital based, patients without diabetes | 102 | 50 (49.0) | 43.3 vs 43.1 | 32.0 vs 40.4 | Ultrasound | Ultrasound, mean of max IMT (L&R) | HLP, sex, Smk, HT, obesity, walking, liver enzymes | 8 |
| Dogru et al58 2013 | Europe | Outpatient clinic | 189 | 115 (60.8) | 31 vs 28 (median) | 100 vs 100 | Liver biopsy | Ultrasound, mean IMT (6 measurements) | – | 6 |
| Kucukazman et al57 2013 | Europe | Outpatient clinic | 161 | 117 (72.7) | 45.8 vs 45.4 | 44 vs 32 | Ultrasound | Ultrasound, mean IMT (6 measurements) | – | 6 |
| Mishra et al56 2013 | Asia | Population based | 645 | 101 (15.7) | 31.6 vs 27.1 | 100 vs 100 | Ultrasound | Ultrasound, mean of max IMT (L&R) | – | 7 |
| Huang et al62 2012 | Asia | Population based | 8632 | 2590 (30.0) | 58.5 vs 58.5 | 31.4 vs 30.9 | Ultrasound | Ultrasound, max IMT (L&R) | – | 7 |
| Kang et al61 2012 | Asia | Outpatient (health screen), MetS(−) | 413 | 157 (38.0) | 52.0 vs 52.5 | 51.0 vs 41.8 | Ultrasound | Ultrasound, mean IMT (L&R) | – | 7 |
| Thakur et al59 2012 | Asia | Hospital based | 80 | 40 (50.0) | 42.1 vs 41.9 | 67.5 vs 67.5 | Ultrasound | Ultrasound, mean IMT (6 measurements) | – | 7 |
| Colak et al63 2012 | Turkey | Outpatient clinic | 87 | 57 (65.5) | 44.2 vs 42.7 | 45.6 vs 46.7 | Liver biopsy | Ultrasound, mean IMT (6 measurements) | – | 6 |
| Agarwal et al66 2011 | Asia | Hospital based, patients with T2DM | 124 | 71 (57.3) | 57 vs 61 | 52.5 vs 58.5 | Ultrasound | Ultrasound, mean IMT | – | 6 |
| Mohammadi et al65 2011 | Iran | Hospital based | 335 | 250 (74.6) | 46.6 vs 44.9 | 55.6 vs 54.1 | Ultrasound | Ultrasound, mean IMT (6 measurements) | HT, DM, HLP, hyperglycaemia | 8 |
| Poanta et al64 2011 | Europe | Outpatient clinic, patients with T2DM | 56 | 38 (67.9) | 59.4 vs 61.5 | 50.0 vs 83.3 | Ultrasound | Ultrasound | – | 5 |
| Kilciler et al69 2010 | Europe | Outpatient clinic | 114 | 60 (52.6) | 31.7 vs 30.3 | 100 vs 100 | Biopsy | Ultrasound, mean IMT (L&R) | Age-matched controls | 6 |
| Salvi et al68 2010 | Europe | Population based | 220 | 92 (41.8) | 50.7 vs 49.3 | 54.3 vs 36.7 | Ultrasound | Ultrasound, mean IMT (6 measurements) | – | 7 |
| Vlachopoulos et al67 2010 | Europe | Outpatient clinic | 51 | 28 (54.9) | 55.4 vs 51.5 | 52.3 vs 64.3 | Biopsy | Ultrasound, mean IMT (L&R) | Age/sex-matched controls | 6 |
| Gastaldelli et al73 2009 | Europe | Population based | 842 | 234 (27.8) | 42 vs 45 | 69.7 vs 24.0 | Fatty liver index >60 | Ultrasound, mean IMT (10 measurements) | – | 6 |
| Karakurt et al72 2009 | Turkey | Not mentioned | 66 | 40 (60.6) | 53 vs 53 | 30.0 vs 42.3 | Ultrasound | Ultrasound, mean IMT (6 measurements) | – | 5 |
| Petit et al71 2009 | Europe | Hospital based, patients with T2DM | 101 | 61 (60.4) | 60.3 vs 60.1 | 44.2 vs 50.0 | MR spectroscopy, liver fat content >5.5% | Ultrasound, mean IMT (6 measurements) | – | 6 |
| Ramilli et al70 2009 | Europe | Outpatient clinic | 154 | 90 (58.4) | 59.3 vs 60.1 | 51.1 vs 45.3 | Ultrasound | Ultrasound, mean of max IMT (L&R) | Age, sex, BMI, Smk, HT, dyslipidaemia, DM | 8 |
| Fracanzani et al74 2008 | Europe | Hospital based | 375 | 125 (33.3) | 50.5 vs 52 | 87.2 vs 87.2 | Ultrasound+biopsy | Ultrasound, mean IMT (6 measurements) | – | 7 |
| Aygun et al75 2008 | Turkey | Hospital based | 80 | 40 (50.0) | 43.2 vs 38.8 | 47.5 vs 50.0 | Biopsy | Ultrasound | Age/sex-matched controls | 7 |
| Targher et al77 2006 1 | Europe | Outpatient clinic, patients with T2DM | 200 | 100 (50.0) | 55 vs 56 | 64.0 vs 67.0 | Ultrasound | Ultrasound, mean IMT (6 measurements) | Age/sex-matched controls | 7 |
| Targher et al76 2006 2 | Europe | Outpatient clinic | 245 | 85 (24.7) | 45 vs 45 | 58.8 vs 59.4 | Biopsy | Ultrasound, mean IMT (6 measurements) | Age, sex, BMI, Smk, LDL, HOMA-IR, MetS | 8 |
| Brea et al79 2005 | Europe | Hospital based | 80 | 30 (50.0) | 53.2 vs 51.6 | 50.0 vs 50.0 | Ultrasound | Ultrasound, mean IMT | – | 7 |
| Targher et al78 2005 | Europe | Outpatient clinic | 90 | 50 (55.5) | 46 vs 46 | 60.0 vs 65 | Biopsy | Ultrasound, mean IMT (6 measurements) | Age, Sex, HOMA-IR, MetS | 8 |
BMI, body mass index; L&R, left and right; MetS, metabolic syndrome; MR, magnetic resonance; NAFLD, non-alcoholic fatty liver disease; NOS, Newcastle–Ottawa Scale; T1DM, type 1 diabetes mellitus; T2DM, type 2 diabetes mellitus.