Table 1.
Cohorts’ characteristics
| SKIPOGH 1 (N = 535) | SKIPOGH 2 (N = 711) | CoLaus| PsyCoLaus (N = 4461) | |
|---|---|---|---|
| Age (years; median [IQR]) | 48 [32–61] | 52 [37–64] | 57 [49–66] |
| Sex (N (%)) | |||
| Male | 272 (51) | 358 (50) | 2065 (46) |
| Female | 263 (49) | 353 (50) | 2396 (54) |
| Current smokers (N (%)) | |||
| Yes | 132 (25) | 199 (28) | 931 (21) |
| No | 400 (75) | 508 (72) | 3524 (77) |
| Unknown (N) | 3 | 4 | 6 |
| Body mass index (kg.m− 2; median [IQR]) | 24.5 [22.1–27.3] | 24.8 [22.3–28.2] | 25.6 [23.0-28.5] |
| Unknown | 1 | 1 | 36 |
| Kidney function (ml/min/1,73 m²; median [IQR])a | 97 [84–108] | 93 [80,105] | 82 [72,94] |
| Unknown (N) | 3 | 2 | |
| Caffeine (ng/ml; median [IQR]) | 642 [232–1384] | 570 [226–1226] | 751 [316–1578] |
| Log caffeine (ng/ml; mean (SD)) | 6.26 (1.38) | 6.19 (1.31) | 6.44 (1.35) |
| Paraxanthine (ng/ml; median [IQR]) | 706 [341–1192] | 659 [317–1149] | 832 [440–1349] |
| Log paraxanthine (ng/ml; mean (SD)) | 6.34 (1.05) | 6.34 (0.98) | 6.52 (1.07) |
| Theophylline (ng/ml; median [IQR]) | 132 [71–223] | 126 [71–214] | 149 [81–236] |
| Log theophylline (ng/ml; mean (SD)) | 4.73 (0.96) | 4.73 (0.89) | 4.83 (0.99) |
| Caffeine + paraxanthine + theophylline (ng/ml; median [IQR]) | 1492 [715–2858] | 1407 [651–2642] | 1799 [877–3203] |
| Log caffeine + paraxanthine + theophylline (ng/ml; mean (SD)) | 7.14 (1.15) | 7.10 (1.08) | 7.31 (1.15) |
| Time (hours; median [IQR]) b | 19 [14–24] | 20 [14–23] | |
| Unknown (N) | 62 | 47 | |
| Espresso cups per day c (median,[IQR]) | 2 [1–4] | 2 [1–4] | |
| Espresso 60 ml cups per day d (median,[IQR]) | 5 [2–9] | 4 [2–7] | |
| Coffee consumption (N (%)) | |||
| None in the last 4 weeks | 425 (10) | ||
| 1–3 times a month | 134 (3) | ||
| 1–2 times a week | 129 (3) | ||
| 3–4 times a week | 230 (5) | ||
| 1 time a day | 1032 (23) | ||
| Two or more a day | 2511 (56) | ||
| Cups of caffeinated beverages (N (%)) | |||
| None per day | 314 (7) | ||
| 1–3 per day | 2930 (66) | ||
| 4–6 per day | 1021 (23) | ||
| More than 6 per day | 164 (4) | ||
Abbreviations IQR = interquartile range; kg = kilograms; m = meter; min = minute; ml = milliliter; N = number; ng = nanogram; SD = standard deviation
aEvaluated using glomerular filtration rate calculated using Chronic Kidney Disease - Epidemiology Collaboration formula
bTime between last caffeine consumption and blood intake
cEstimated by considering the answer to question 2 of the questionnaire (supplementary Table 1)
dEstimated by considering all caffeinated drinks