Table 4.
Linear and Logistic Regression Analysis of Insulin Resistance Outcomes Associated With Urinary Phthalate Metabolites (Tertiled)
| LMW Metabolites | HMW Metabolites | DEHP Metabolites | DIDP Metabolites | DINP Metabolites | |
|---|---|---|---|---|---|
| Model D, Increment, HOMA-IR (n = 350) Predicted HOMA-IR | |||||
| First Tertile | Reference | Reference | Reference | Reference | Reference |
| 1.08 (0.96–1.20) | 0.99 (0.88–1.10) | 1.02 (0.91–1.13) | 1.05 (0.95–1.15) | 0.99 (0.89–1.10) | |
| Second Tertile | +0.08 (−0.08, 0.24) | 0.18 (0.01, 0.35)a | 0.07 (−0.09, 0.23) | 0.06 (−0.08, 0.21) | 0.07 (−0.09, 0.22) |
| 1.16 (1.06–1.26) | 1.17 (1.06–1.28) | 1.09 (0.98–1.19) | 1.11 (1.00–1.22) | 1.06 (0.95–1.16) | |
| Third Tertile | −0.03 (−0.21, 0.15) | 0.14 (−0.03, 0.30) | 0.16 (−0.005, 0.33) | 0.08 (−0.08, 0.25) | 0.23 (0.08, 0.38)b |
| 1.05 (0.94–1.15) | 1.13 (1.03–1.23) | 1.18 (1.07–1.30) | 1.13 (1.01–1.25) | 1.22 (1.12–1.32) | |
| Model D, OR, Insulin Resistance (n = 350) Prevalence | |||||
| First Tertile | Reference | Reference | Reference | Reference | Reference |
| 24.8.% (17.5–32.2) | 18.8% (13.2–24.5) | 20.5% (14.5–26.5) | 26.0% (19.6–32.3) | 23.4% (17.2–29.6) | |
| Second Tertile | 1.91 (0.86–4.28) | 3.51 (1.43–8.63)b | 2.32 (0.98–5.51) | 1.58 (0.75–3.34) | 1.63 (0.72–3.68) |
| 33.3% (26.2–40.6) | 33.8% (25.6–41.9) | 30.5% (23.0–38.0) | 32.1% (24.7–39.5) | 29.4% (21.9–36.9) | |
| Third Tertile | 1.35 (0.53–3.44) | 4.30 (1.81–10.22)b | 3.85 (1.60–9.24)b | 1.32 (0.56–3.13) | 2.33 (1.07–5.07)a |
| 28.6% (21.3–36.0) | 36.7% (29.3–44.1) | 37.7% (29.8–45.6) | 29.6% (21.3–38.0) | 34.4% (27.3–41.6) |
Increases are per log unit in urinary LMW/HMW/DEHP/DIDP/DINP metabolite concentration. See Methods for calculation.
Tertiles for LMW: <0.275 μM (n = 106); 0.275–0.696 μM (n = 118); ≥0.696 μM (n = 132). Tertiles for HMW: <0.238 μM (n = 127); 0.238–0.535 μM (n = 104); ≥0.535 μM (n = 125). Tertiles for DEHP: <0.105 μM (n = 130); 0.105–0.241 μM (n = 113); ≥0.241 μM (n = 113). Tertiles for DIDP: <0.006 μM (n = 146); 0.006–0.013 μM (n = 107); ≥0.013 μM (n = 103). Tertiles for DINP: <0.045 μM (n = 124); 0.045–0.120 μM (n = 110); ≥0.120 μM (n = 122).
All models control for continuous urinary creatinine, age, and caloric intake as well as sex, PIR, serum cotinine, BMI, race/ethnicity categories, and PA.
Results using unweighted modeling are presented.
P < .05.
P < .01.