Table 3:
Association between metalworking fluids and ESRD classification: Exposure modeled with cubic splines in competing risk regression.
| Cumulative exposure | All males | White males | Black males | |||||
|---|---|---|---|---|---|---|---|---|
| ESRD classification | MWF type | Percentile* | sHR† | 95% CI | sHR† | 95% CI | sHR† | 95% CI |
| Diabetic nephropathy | n=184 cases | n=123 cases | n=61 cases | |||||
| Straight | 60 | 0.99 | 0.94, 1.04 | 1.01 | 0.96, 1.07 | 0.97 | 0.68, 1.39 | |
| 70 | 0.99 | 0.92, 1.07 | 1.02 | 0.94, 1.10 | 0.95 | 0.58, 1.57 | ||
| 80 | 0.98 | 0.84, 1.14 | 1.04 | 0.89, 1.22 | 0.87 | 0.38, 1.97 | ||
| 90 | 0.95 | 0.66, 1.39 | 1.12 | 0.75, 1.67 | 0.46 | 0.12, 1.79 | ||
| Soluble | 60 | 1.28 | 1.00, 1.64 | 1.24 | 0.90, 1.71 | 1.39 | 0.94, 2.05 | |
| 70 | 1.38 | 0.98, 1.92 | 1.32 | 0.86, 2.01 | 1.56 | 0.91, 2.66 | ||
| 80 | 1.45 | 0.96, 2.20 | 1.36 | 0.81, 2.27 | 1.75 | 0.88, 3.49 | ||
| 90 | 1.38 | 0.84, 2.26 | 1.23 | 0.68, 2.24 | 1.87 | 0.80, 4.38 | ||
| Synthetic | 60 | 1.15 | 0.93, 1.41 | 1.07 | 0.87, 1.32 | 1.73 | 1.04, 2.87 | |
| 70 | 1.25 | 0.88, 1.77 | 1.12 | 0.78, 1.61 | 2.32 | 1.05, 5.10 | ||
| 80 | 1.29 | 0.87, 1.93 | 1.14 | 0.75, 1.73 | 2.54 | 1.05, 6.16 | ||
| 90 | 1.39 | 0.82, 2.39 | 1.18 | 0.66, 2.10 | 2.99 | 0.96, 9.28 | ||
| Glomerulonephritis | n=59 cases | n=44 cases | n=15 cases | |||||
| Straight | 60 | 1.18 | 0.99, 1.41 | 1.21 | 1.00, 1.47 | 4.16 | 1.00, 17.27 | |
| 70 | 1.28 | 0.98, 1.65 | 1.33 | 1.00, 1.76 | 3.76 | 0.78, 18.15 | ||
| 80 | 1.59 | 0.96, 2.63 | 1.73 | 1.00, 3.00 | 0.64 | 0.07, 6.04 | ||
| 90 | 2.09 | 0.77, 5.67 | 2.48 | 0.82, 7.54 | - | - | ||
| Soluble | 60 | 1.02 | 0.66, 1.57 | 1.15 | 0.73, 1.79 | 0.64 | 0.21, 1.92 | |
| 70 | 1.02 | 0.57, 1.83 | 1.21 | 0.66, 2.22 | 0.55 | 0.13, 2.24 | ||
| 80 | 1.02 | 0.49, 2.14 | 1.28 | 0.58, 2.80 | 0.47 | 0.09, 2.50 | ||
| 90 | 1.00 | 0.40, 2.52 | 1.38 | 0.52, 3.68 | 0.38 | 0.06, 2.44 | ||
| Synthetic | 60 | 0.96 | 0.54, 1.72 | 1.00 | 0.58, 1.71 | - | ||
| 70 | 0.92 | 0.37, 2.31 | 0.98 | 0.40, 2.36 | - | |||
| 80 | 0.90 | 0.32, 2.53 | 0.96 | 0.35, 2.61 | - | |||
| 90 | 0.82 | 0.23, 2.97 | 0.87 | 0.25, 3.10 | - | |||
Abbreviations: CI, confidence interval; ESRD, end-stage renal disease; HR, hazard ratio; MWF, metalworking fluids
*
For each MWF type, a restricted cubic spline was used to estimate the HR; we present the HR at specific points along the spline, based on percentile of exposure for the exposed cases
†
Adjusted for age, calendar year, year hired, plant, other MWFs, and time since hire (as the analytic timeline)