Characteristics of studies included in this systematic review and meta-analysis
| First author, year [ref.] | Assessment method | Measurements and scale | COPD | Controls | |||||||
| Subjects n | Age years | Male % | FEV1 % | CVD# | Subjects n | Age years | Male % | Smoking status | |||
| Barak, 2017 [30] | FMD | FMD% (% proportional change from baseline) | 17 | 69.0±8.1 | 64.7 | 31.8±11.0 | 5.9 | 10 | 65.3±7.3 | 70.0 | Former smokers n=4; nonsmokers n=6 |
| Barr, 2007 [42] | FMD | FMD% (% proportional change from baseline) | 44 | n/a | 54.5 | n/a | n/a | 63 | 70.0±5.0 | 54.0 | Former smokers |
| Blum, 2014 [28] | FMD | FMD% (% proportional change from baseline) | 23 | 64.4±8.4 | 56.0 | 45.0±14.0 | 26.0 | 22 | 44.7±11.7 | 46.0 | Nonsmokers |
| Costanzo, 2017 [29] | FMD | FMD% (% proportional change from baseline) | 41 | 74.0±5.8 | 56.1 | 61.9±16.6 | n/a (0% CAD, but data about PAD and stroke missing) | 35 | 73.8±6.6 | 45.7 | n/a |
| Eickhoff, 2008 [31] | FMD and NMD | FMD% and NMD% (% proportional change from baseline) | 60 | 62.0±8.0 | 56.6 | 41.0±18.0 | 0 | 40 | 60.9±10.4 | 37.5 | Nonsmokers n=20; smokers n=20 |
| Gelinas, 2017 [32] | FMD and NMD | FMD% and NMD% (% proportional change from baseline) | 24 | 69.9±2.8 | 54.2 | 68.0±19.0 | 0 | 20 | 62.6±1.1 | 50.0 | n/a (excluded if >10 pack-years) |
| Hartmann, 2016 [33] | FMD and NMD | FMD% and NMD% (% proportional change from baseline) | 10 | 67.0±3.0 | 40.0 | 60.0±5.0 | 0 | 10 | 66.0±2.0 | 40.0 | Nonsmokers |
| Ives, 2014 [34] | FMD | FMD% (% proportional change from baseline) | 30 | 66.0±2.0 | 50.0 | 55.0±4.0 | 6.66 | 30 | 66.0±2.0 | 50.0 | Nonsmokers |
| Keymel, 2018 [25] | FMD and NMD, VOP | FMD%, NMD% (% proportional change from baseline) and FBF after reactive hyperaemia (mL·min−1 per 100 mL tissue) | 17 | 66.0±8.0 | 100 | 59.0±17.0 | 100.0 | 16 | 64±10.0 | 100 | Former smokers n=16 |
| Kuzubova, 2013 [43] | FMD | FMD% (% proportional change from baseline) | 63 | 60.4±1.0 | 100 | 45.1±2.4 | n/a | 95 | 57.3±1.7 | 100 | 57% former or current smokers |
| Maclay, 2009 [23] | VOP | FBF after bradykinin infusion (mL·min−1 per 100 mL tissue) | 18 | 65.0±5.4 | 100 | 47.6±20.1 | 0 | 17 | 63.0±6.0 | 100 | Nonsmokers |
| Majewski, 2020 [27] | FMSF | Reactive hyperaemia (% proportional change from baseline) | 26 | 66.9±8.3 | 42.3 | 63.7±13.1 | 7.69 | 20 | 52.5±13.2 | 60.0 | Smokers n=2; former smokers n=3; nonsmokers n=15 |
| Malerba, 2018 [26] | PAT | RHI | 16 | 74.2±8.6 | 62.5 | 69.5±19.0 | 0 | 16 | 75.1±3.2 | 62.5 | Smokers n=3; former smokers n=7; nonsmokers n=6 |
| Marchetti, 2011 [35] | FMD and NMD | FMD% and NMD% (% proportional change from baseline) | 8 | 61.0±8.0 | 50.0 | 33.0±22.0 | 0 | 9 | 53.0±6.0 | 66.6 | Nonsmokers |
| Moro, 2008 [36] | FMD and NMD | FMD% and NMD% (% proportional change from baseline) | 44 | 76.7 | 61.4 | n/a | 15.9 | 48 | 73.4 | 27.1 | Smokers n=7; former smokers n=15; nonsmokers n=26 |
| Ozben, 2010 [37] | FMD and NMD | FMD% and NMD% (% proportional change from baseline) | 30 | 64.2±10.9 | 73.3 | 51.0±15.0 | 33.3 | 20 | 61.9±7.4 | 75.0 | Nonsmokers |
| Piccari, 2020 [38] | FMD | FMD% (% proportional change from baseline) | 61¶ | 62.5±4.7 | 83.6 | 43.6±19.7 | n/a | 47¶ | 55.2±8.1 | 44.7 | Nonsmokers n=26; smokers n=20 |
| Pizarro, 2014 [39] | FMD and NMD | FMD% and NMD% (% proportional change from baseline) | 62 | 62.0±8.0 | 93.5 | 53.0±18.0 | 0 | 35 | 58.5±7.1 | 19.0 | Nonsmokers n=18; smokers n=17 |
| Rodriguez-Miguelez, 2015 [40] | FMD | FMD% (% proportional change from baseline) | 17 | 56.0±7.0 | 35.3 | 58.0±15.0 | 0 | 15 | 58.0±7.0 | 33.3 | Nonsmokers n=13; smokers n=2 |
| Yang, 2017 [24] | VOP | FBF after bradykinin infusion (% proportional change from baseline) | 12 | 63.0±6.0 | 100 | 53.0±13.0 | n/a | 12 | 64.0±7.0 | 100 | Nonsmokers |
| Zelt, 2018 [41] | FMD | FMD% (% proportional change from baseline) | 16 | 66.0±8.0 | 31.3 | 86.2±13.8 | 12.5 | 16 | 64.0±8.0 | 43.8 | Smoker n=1; former smokers n=4; nonsmokers n=11 |
Data are presented as mean±sd, unless otherwise stated. FEV1: forced expiratory volume in 1 s; CVD: cardiovascular disease; FMD: flow-mediated dilatation; n/a: not available; CAD: coronary artery disease; PAD: peripheral artery disease; NMD: nitroglycerin-mediated dilatation; VOP: venous occlusion plethysmography; FBF: forearm blood flow; FMSF: flow-mediated skin fluorescence; PAT: peripheral arterial tonometry; RHI: reactive hyperaemia index. #: includes CAD, PAD and stroke; ¶: n=1 participant excluded from analysis due to missing data.