Table 1.
Clinical characteristics of the training cohort (iCOMPEER) by CPET cluster
| Cluster 1 (n = 121) | Cluster 2 (n = 238) | Cluster 3 (n = 365) | Cluster 4 (n = 396) | Cluster 5 (n = 279) | |
|---|---|---|---|---|---|
| Anthropometrics | |||||
| Age, y | 43.19 ± 11.35 | 49.54 ± 11.75∗ | 54.65 ± 11.62∗† | 60.08 ± 10.97∗†‡ | 64.99 ± 9.89∗†‡& |
| Females, n (%) | 40 (33.06) | 89 (37.39) | 158 (43.29)∗ | 144 (36.36) | 97 (34.77)‡ |
| Weight, kg | 92.78 ± 21.91 | 87.77 ± 17.24∗ | 82.34 ± 16.32∗† | 79.63 ± 14.25∗†‡ | 75.32 ± 14.23∗†‡& |
| Height, cm | 178.45 ± 8.5 | 174.58 ± 8.29∗ | 170.79 ± 8.42∗† | 169.39 ± 8.39∗†‡ | 167.55 ± 8.18∗†‡& |
| Body mass index, kg/m2 | 29.11 ± 6.38 | 28.84 ± 5.58 | 28.23 ± 5.32 | 27.72 ± 4.38∗† | 26.81 ± 4.6∗†‡& |
| Medical history | |||||
| Hypertension, n (%) | 53 (43.8) | 144 (60.5)∗ | 247 (67.67)∗ | 301 (76.01)∗†‡ | 253 (90.68)∗†‡& |
| DM type I or II, n (%) | 7 (5.79) | 22 (9.24) | 41 (11.23) | 57 (14.39)∗ | 65 (23.3)∗†‡& |
| Chronic kidney disease, n (%) | 0 (0.0) | 2 (0.84) | 15 (4.11)∗† | 22 (5.56)∗† | 34 (12.19)∗†‡& |
| Asthma or COPD, n (%) | 5 (4.13) | 5 (2.1) | 12 (3.29) | 26 (6.57)†‡ | 18 (6.45)† |
| Cardiovascular disease, n (%) | 37 (30.58) | 112 (47.06)∗ | 191 (52.33)∗ | 273 (68.94)∗†‡ | 226 (81.0)∗†‡& |
| Cardiovascular intervention, n (%) | 32 (26.45) | 103 (43.28)∗ | 180 (49.32)∗ | 255 (64.39)∗†‡ | 216 (77.42)∗†‡& |
| Medication | |||||
| Antihypertensive drugs, n (%) | 34 (28.1) | 114 (47.9)∗ | 212 (58.08)∗† | 275 (69.44)∗†‡ | 232 (83.15)∗†‡& |
| Beta blockers, n (%) | 16 (13.22) | 74 (31.09)∗ | 145 (39.73)∗† | 213 (53.79)∗†‡ | 184 (65.95)∗†‡& |
| CCB, n (%) | 5 (4.13) | 23 (9.66) | 66 (18.08)∗† | 63 (15.91)∗† | 68 (24.37)∗†& |
| ACE or ARB, n (%) | 28 (23.14) | 77 (32.35) | 140 (38.36)∗ | 200 (50.51)∗†‡ | 174 (62.37)∗†‡& |
| Diuretics, n (%) | 3 (2.48) | 26 (10.92)∗ | 35 (9.59)∗ | 48 (12.12)∗ | 48 (17.2)∗†‡ |
| Lipid lowering drugs, n (%) | 36 (29.75) | 110 (46.22)∗ | 214 (58.63)∗† | 296 (74.75)∗†‡ | 230 (82.44)∗†‡& |
| Anti-thrombotic drugs, n (%) | 36 (29.75) | 119 (50.0)∗ | 202 (55.34)∗ | 290 (73.23)∗†‡ | 228 (81.72)∗†‡& |
| Antidiabetic drugs, n (%) | 7 (5.79) | 24 (10.08) | 38 (10.41) | 50 (12.63)∗ | 58 (20.79)∗†‡& |
| Spirometry | |||||
| FEV₁, L | 3.84 ± 0.61 | 3.48 ± 0.59∗ | 3.11 ± 0.56∗† | 2.97 ± 0.59∗†‡ | 2.59 ± 0.54∗†‡& |
| FEV₁ %predicted | 103.86 ± 9.89 | 103.88 ± 11.88 | 102.63 ± 12.96 | 103.42 ± 14.84 | 98.42 ± 16.22∗†‡& |
| FVC₁, L | 4.83 ± 0.78 | 4.41 ± 0.75∗ | 3.98 ± 0.74∗† | 3.86 ± 0.74∗†‡ | 3.43 ± 0.67∗†‡& |
| FVC %predicted | 107.23 ± 8.78 | 106.9 ± 11.48 | 105.78 ± 13.11 | 107.18 ± 14.02 | 102.3 ± 14.99∗†‡& |
| FEV₁/FVC (%) | 97.02 ± 6.67 | 97.29 ± 5.7 | 97.34 ± 7.06 | 96.69 ± 8.1 | 96.39 ± 9.68 |
| CPET data at rest | |||||
| HR (at rest), beats/min | 73.5 ± 14.81 | 73.28 ± 14.05 | 73.88 ± 13.7 | 71.6 ± 13.38‡ | 71.46 ± 14.66‡ |
| SBP (at rest), mm Hg | 118.42 ± 18.05 | 122.55 ± 19.17∗ | 125.78 ± 20.02∗† | 128.41 ± 19.75∗† | 130.91 ± 21.87∗†‡ |
| DBP (at rest), mm Hg | 77.79 ± 11.62 | 78.77 ± 11.08 | 78.44 ± 11.31 | 77.52 ± 10.99 | 75.85 ± 12.79†‡ |
| VO₂, mL/min | 679.29 ± 139.06 | 603.55 ± 123.28∗ | 547.25 ± 119.58∗† | 506.53 ± 113.82∗†‡ | 432.21 ± 104.51∗†‡& |
| PETO₂, mm Hg | 106.04 ± 4.86 | 107.09 ± 5.25 | 107.3 ± 5.06∗ | 108.08 ± 5.12∗†‡ | 110.2 ± 5.2∗†‡& |
| PETCO₂, mm Hg | 35.52 ± 2.79 | 35.08 ± 3.09 | 34.57 ± 3.15∗† | 34.18 ± 3.17∗† | 32.9 ± 3.52∗†‡& |
| RER | 0.81 ± 0.09 | 0.82 ± 0.09 | 0.82 ± 0.08 | 0.83 ± 0.08 | 0.85 ± 0.09∗†‡& |
| CPET data at peak | |||||
| Load, watt | 247.4 ± 48.02 | 200.76 ± 39.43∗ | 167.41 ± 35.45∗† | 144.91 ± 32.34∗†‡ | 115.73 ± 30.98∗†‡& |
| VO₂, mL/min | 2865.87 ± 530.02 | 2267.56 ± 419.18∗ | 1846.28 ± 357.03∗† | 1587.16 ± 307.14∗†‡ | 1217.52 ± 264.8∗†‡& |
| VO₂ per kg, mL/kg/min | 32.17 ± 8.26 | 26.47 ± 5.64∗ | 22.96 ± 4.85∗† | 20.26 ± 4.07∗†‡ | 16.47 ± 3.78∗†‡& |
| VO₂ percentage predicted, % | 115.95 ± 14.31 | 101.2 ± 13.7∗ | 91.11 ± 12.0∗† | 82.22 ± 12.06∗†‡ | 68.2 ± 11.78∗†‡& |
| HR, bpm | 171.65 ± 15.1 | 158.69 ± 18.93∗ | 148.92 ± 19.25∗† | 138.55 ± 21.56∗†‡ | 125.11 ± 21.48∗†‡& |
| HR percentage predicted, % | 97.16 ± 7.07 | 93.11 ± 9.37∗ | 90.16 ± 10.7∗† | 86.71 ± 12.63∗†‡ | 80.79 ± 13.38∗†‡& |
| O₂ pulse, mL/beat | 16.81 ± 3.36 | 14.53 ± 3.36∗ | 12.65 ± 3.11∗† | 11.78 ± 3.08∗†‡ | 9.97 ± 2.52∗†‡& |
| O₂ pulse/kg, mL/beat/kg | 0.19 ± 0.05 | 0.17 ± 0.04∗ | 0.16 ± 0.03∗† | 0.15 ± 0.03∗†‡ | 0.13 ± 0.03∗†‡& |
| SBP, mm Hg | 180.74 ± 31.95 | 180.72 ± 30.89 | 177.22 ± 30.48 | 175.24 ± 28.54† | 169.54 ± 28.4∗†‡& |
| VE, L/min | 102.6 ± 25.85 | 85.09 ± 21.71∗ | 71.7 ± 19.77∗† | 64.11 ± 16.4∗†‡ | 52.07 ± 15.74∗†‡& |
| VE/VCO₂ slope | 26.2 ± 3.21 | 27.26 ± 3.61∗ | 28.42 ± 3.97∗† | 29.29 ± 4.31∗†‡ | 31.35 ± 4.68∗†‡& |
| PETO₂, mm Hg | 113.57 ± 4.78 | 114.83 ± 4.43∗ | 115.02 ± 4.74∗ | 115.62 ± 5.1∗† | 116.17 ± 4.78∗†‡ |
| PETCO₂, mm Hg | 39.7 ± 3.88 | 38.81 ± 3.94∗ | 37.87 ± 4.13∗† | 37.25 ± 4.0∗†‡ | 35.97 ± 4.06∗†‡& |
| RER | 1.14 ± 0.07 | 1.17 ± 0.07∗ | 1.17 ± 0.08∗ | 1.18 ± 0.09∗†‡ | 1.18 ± 0.1∗ |
| Borg score | 16.58 ± 1.55 | 16.26 ± 1.51 | 16.04 ± 1.53∗ | 15.79 ± 1.58∗†‡ | 15.36 ± 1.65∗†‡& |
Data are presented as mean ± SD or number of subjects (%). Significance for between-phenogroups differences: ∗p < 0.05 vs. cluster 1; †p < 0.05 vs. cluster 2; ‡p < 0.05 vs. cluster 3; &p < 0.05 vs. cluster 4. BMI, body mass index; CPET, cardiopulmonary exercise testing; DM, diabetes mellitus; COPD, chronic obstructive pulmonary disease; CCB, calcium channel blocker; ACE, angiotensin-converting enzyme inhibitors; ARB, angiotensin receptor blocker; HR, heart rate; SBP, systolic blood pressure; DBP, diastolic blood pressure; CV, cardiovascular; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; HR, heart rate; PETO2, end-tidal partial pressure of oxygen; PETCO2, end-tidal partial pressure of carbon dioxide; RER, respiratory exchange ratio; SBP, systolic blood pressure; VCO2, rate of carbon dioxide produced; VE, minute ventilation; VE/VCO2 slope, ventilatory efficiency; VO2, rate of oxygen uptake.