Table 2:
Descriptive data of biomarkers, work practices, and kidney function, averaged from all time points and their correlations with copeptin.
| Plasma Copeptin | ||||
|---|---|---|---|---|
| Characteristics | N | Mean (SD) | r | p-value |
| Change in Bodyweight | 265 | 0.29 (3.18) | −0.08 | 0.23 |
| Urine Specific Gravity | 265 | 1.005 (0.007) | 0.58 | <0.01 |
| - > 1.020, n (%) | 265 | 24 (9%) | ||
| Serum Osmolality, mmol/kg | 264 | 280.07 (7.78) | 0.40 | <0.01 |
| Serum Sodium, mmol/L | 265 | 135.22 (3.63) | 0.26 | <0.01 |
| Urine Sodium, mEq/L | 252 | 23.56 (26.01) | 0.38 | <0.01 |
| Creatine Kinase, U/L | 264 | 403.80 (291.76) | −0.01 | 0.82 |
| Cane cut during shift, tons | 202a | 6.12 (2.26) | −0.09 | 0.21 |
| Water, liters | 263 | 13.27 (5.33) | −0.33 | <0.01 |
| Electrolyte fluid, liters b | 260 | 2.50 (1.50) | −0.32 | <0.01 |
| Number of sugar-sweetened beverages | 257 | 0.45 (0.93) | 0.03 | 0.60 |
| Urine ACR, mg/mmol | 252 | 2.58 (4.66) | −0.01 | 0.86 |
| Urine NGAL, ng/mL | 253 | 9.71 (13.38) | −0.01 | 0.88 |
| Serum creatinine, µmol/Lc | 265 | 85.75 (22.10) | 0.49 | <0.01 |
| eGFR, ml/min/1.73 m2 | 265 | 105.73 (21.73) | −0.44 | <0.01 |
| eGFR Categorized | ≥ 60 (n= 251) | < 60 (n=14) | p-value* | |
| Copeptin, pmol/L | 4.73 (4.49) | 12.37 (11.02) | <0.01 | |
Abbreviations: ACR: albumin-to-creatinine ratio; NGAL: neutrophil gelatinase-associated lipocalin; eGFR: estimated glomerular filtration rate.
a
Reduced N since 20% of the participants are seeders and do not cut cane.
b
Electrolyte fluid was distributed in 500-ml bags.
c
Conversion factor for creatinine in μmol/L to mg/dL divide by 88.4
*
p-value based on Wilcoxon rank sums test.