Table 1 Characteristics of study participants
Characteristic | Total population | Discovery subset | Validation subset | P |
|---|---|---|---|---|
N = 1630 | n = 883 | n = 747 | ||
Sex | ||||
 Males | 438 (26.9%) | 237 (26.8%) | 201 (26.9%) | 0.9756 |
 Females | 1192 (73.1%) | 646 (73.2%) | 546 (73.1%) | |
Age, years (mean ± SD) | 52.4 ± 13.8 | 51.5 ± 13.5 | 53.5 ± 14.1 | 0.0050 |
BMI*, kg/m2 (mean ± SD) | 33.6 ± 5.4 | 33.7 ± 5.6 | 33.5 ± 5.3 | 0.4758 |
BMI* categorical | ||||
 Overweight (25–30 kg/m2) | 438 (26.9%) | 238 (27.0%) | 200 (26.8%) | 0.7290 |
 Obese (≥30 kg/m2) | 1191 (73.0%) | 645 (73.0%) | 546 (73.1%) | |
 Missing | 1 (0.1%) | _ | 1 (0.1%) | |
Smoking status | ||||
 Never smoker | 794 (48.7%) | 447 (50.6%) | 347 (46.5%) | 0.3425 |
 Former smoker | 575 (35.3%) | 303 (34.3%) | 272 (36.4%) | |
 Current smoker | 258 (15.8%) | 131 (14.8%) | 127 (17%) | |
 Missing | 3 (0.2%) | 2 (0.2%) | 1 (0.1%) | |
Year of enrollment | ||||
 2010 | 90 (5.5%) | 90 (10.2%) | _ | _ |
 2011 | 409 (25.1%) | 409 (46.3%) | _ | |
 2012 | 384 (23.6%) | 384 (43.5%) | _ | |
 2013 | 304 (18.7%) | _ | 304 (40.7%) | |
 2014 | 324 (19.9%) | _ | 324 (43.4%) | |
 2015 | 119 (7.3%) | _ | 119 (15.9%) | |
Season of enrollment | ||||
 Winter | 487 (29.9%) | 223 (25.3%) | 264 (35.3%) | < 0.0001 |
 Spring | 430 (26.4%) | 227 (25.7%) | 203 (27.2%) | |
 Summer | 213 (13.1%) | 106 (12%) | 107 (14.3%) | |
 Autumn | 500 (30.7%) | 327 (37%) | 173 (23.2%) | |
Living area | ||||
 City of Milan | 975 (59.8%) | 493 (55.8%) | 482 (64.5%) | 0.0004 |
 Outside Milan | 655 (40.2%) | 390 (44.2%) | 265 (35.5%) | |
Fibrinogen, mg/dl (median [Q1-Q3]) | 325 [290–366] | 328 [295–368] | 322 [281–365] | 0.0056 |