Relationships between lead biomarkers and diurnal salivary cortisol indices in pregnant women from Mexico City: a cross-sectional study

Table 2 Adjusted change in cortisol area under the curve (AUC) according to blood, tibia, and patella Pb concentrations in Mexico City women (2007–2011)

Pb biomarker/quantile	N	GM salivary cortisol AUC (nmol-hours)	% Difference in cortisol AUC nmol-hours (95% CI)
Blood Pb ¹
Quintile 1 (0- < 1.8 µg/dL)	185	82.0	Ref
Quintile 2 (1.8- < 2.4 µg/dL)	183	88.6	8 (−1, 18)
Quintile 3 (2.4- < 3.4 µg/dL)	184	89.8	9 (0, 19)
Quintile 4 (3.4- < 5.1 µg/dL)	182	88.8	8 (−1, 18)
Quintile 5 (≥5.1 µg/dL)	184	83.8	2 (−6, 12)
Continuous, per 2.5 µg/dL	918		−1 (−4, 1)
Tibia Pb ²
Quantile 1 (<2 µg/g)	266	87.8	Ref
Quantile 2 (2- < 4.3 µg/g)	82	83.2	−5 (−14, 5)
Quantile 3 (4.3- < 6.7 µg/g)	82	89.3	2 (−8, 13)
Quantile 4 (6.7- < 11.1 µg/g)	82	87.5	0 (−10, 10)
Quantile 5 (≥11.1 µg/g)	82	93.4	6 (−4, 18)
Patella Pb ²
Quantile 1 (<2 µg/g)	241	86.6	Ref
Quantile 2 (2- < 4.5 µg/g)	86	87.6	1 (−8, 12)
Quantile 3 (4.5- < 7.8 µg/g)	87	81.8	−6 (−14, 4)
Quantile 4 (7.8- < 12.7 µg/g)	86	97.0	12 (1, 24)
Quantile 5 (>12.7-43.2 µg/g)	87	90.3	4 (−6, 16)

GM: Geometric Mean, AUC: Area Under the Curve.
1-Adjusted for maternal age (continuous years), education (continuous years), body mass index (continuous), marital status (married, free union, or single/separated/divorced), gestational age at time of cortisol collection (continuous weeks), parity (1, 2, 3, or 4+), and maternal smoking status during pregnancy (never, former, or current).
2-Adjusted for above covariates and maternal calf circumference at 1-month postpartum.

ISSN: 1476-069X