. Author manuscript; available in PMC: 2017 May 1.

Published in final edited form as: Paediatr Perinat Epidemiol. 2016 Feb 5;30(3):229–237. doi: 10.1111/ppe.12278

Table 4.

Adjusted^a odds ratios and 95% confidence intervals for development of GDM and RERI and AP for interactions between maternal smoking and 25(OH)D concentration

Smoking in pregnancy^b	25(OH)D category
	≥50 nmol/L	30–<50 nmol/L	<30 nmol/L
	N cases/N controls	N cases/N controls	N cases/N controls
	OR (95% CI)^a	OR (95% CI)^a	OR (95% CI)^a
No	117/808	134/517	27/104
No	1.00 (Reference)	1.34 (1.00, 1.81)	1.14 (0.66, 1.87)
Yes	29/163	37/137	20/35
Yes	1.18 (0.73, 1.89)	1.48 (0.95, 2.31)	3.73 (1.95, 7.14)
RERI [95% CI]	–	−0.04 (−0.87, 0.79)	2.44 (0.03, 4.85)
AP [95% CI]	–	−0.03 (−0.59, 0.54)	0.65 (0.36, 0.94)

Adjusted for maternal age, body mass index, gestational week of blood collection, study site, season, and year of blood collection.

P-value for multiplicative interaction = 0.04.