Table 4.

Differences in OGTT-based insulin measures per interquartile range (6.24 μg/L) increase in urinary total arsenic (n=221).

	With creatinine adjustment		Without creatinine adjustment
	Model 1*	Model 2†	Model 1	Model 2
Fasting glucose (mg/dL)	0.82 (0.30, 1.34)‡	0.57 (0.059, 1.09)§	0.81 (0.29, 1.32)‡	0.54 (0.030, 1.05)§
Glucose (120 min) (mg/dL)	1.12 (−0.33, 2.57)	0.74 (−0.77, 2.25)	1.63 (0.27, 3.00)§	1.17 (−0.26, 2.59)
Measures of insulin sensitivity
Stumvoll MCR (mg/(kg×min))	−0.27 (−0.42, −0.11)‡	−0.23 (−0.38, −0.089)‡	−0.30 (−0.45, −0.15)‡	−0.27 (−0.41, −0.13)‡
Stumvoll ISI (μmol/(kg×min×pM))	−0.0033 (−0.0052, −0.0014)‡	−0.0029 (−0.0047, −0.0011)‡	−0.0037 (−0.0055, −0.0019)‡	−0.0034 (−0.0051, −0.0017)‡
Matsuda index (percent difference)	−3.8 (−6.2, −1.3)‡	−1.5 (−4.3, 1.2)	−4.3 (−6.6, −1.9)‡	−1.8 (−4.5, 0.95)
Measures of β-cell function
Stumvoll insulin secretion, phase 1 (pM)	19.4 (−22.5, 61.3)	4.8 (−37.1, 46.8)	24.9 (−14.5, 64.2)	7.9 (−32.2, 47.9)
Stumvoll insulin secretion, phase 2 (pM)	4.9 (−4.5, 14.3)	1.5 (−7.9, 10.9)	6.3 (−2.5, 15.1)	2.3 (−6.6, 11.3)
Insulinogenic index (percent difference)	0.51 (−6.7, 8.3)	−1.8 (−8.8, 6.0)	0.81 (−6.1, 8.2)	−1.8 (−8.7, 5.6)
Fasting-state measures
HOMA-IR (percent difference)	3.1 (0.79, 5.4)‡	0.72 (−1.8, 3.3)	3.7 (1.4, 6.1)‡	1.1 (−1.5, 3.7)
HOMA-%β (percent difference)	−0.64 (−3.2, 2.0)	−1.8 (−4.6, 1.1)	−0.10 (−2.7, 2.5)	−1.4 (−4.2, 1.4)

^*Model 1 adjusted for age and sex in generalized estimating equations accounting for sibship.

^†Model 2 additionally adjusted for waist-to-hip ratio and BMI. BMI was not adjusted when modeling Stumvoll MCR and Stumvoll ISI because BMI is used to calculate those indices. For both model 1 and 2, results when urine creatinine was included as a covariate and when it was not are presented separately.

^‡p-value <0.01,

^§0.01≤p-value <0.05.