The effect of nicotine-containing products and fetal sex on placenta-associated circulating midpregnancy biomarkers

Table 3 Effect of nicotine exposure on midpregnancy circulating angiogenic biomarkers (Nicotine exposure study group, n = 2278)

Nicotine exposure	N	%	Univariable
			sFlt-1			PlGF			sFlt-1/ PlGF-ratio
			β	95% CI	P	β	95% CI	P	β	95% CI	P
Snus	2090				0.091			0.023			0.072
Never (Ref.)	1622	77.6
Stopped before pregnancy	313	15.0	0.02	− 0.01; 0.04		− 0.02	− 0.05;0.00		0.04	0.01;0.07
Stopped when recognized pregnancy	143	6.8	− 0.01	− 0.05; 0.03		− 0.03	− 0.06;0.01		0.02	− 0.03;0.06
Current	12	0.6	− 0.12	− 0.2;0.00		− 0.13	− 0.2;(− 0.01)		0.01	− 0.14;0.15
Smoke	2200				0.530			0.360			0.282
Never (Ref.)	1702	77.3
Stopped before pregnancy	388	17.6	− 0.01	− 0.03;0.01		− 0.00	− 0.03;0.02		− 0.01	− 0.04;0.02
Stopped when recognized pregnancy	95	4.3	− 0.02	− 0.06;0.02		− 0.02	− 0.06;0.03		− 0.01	− 0.06;0.05
Current	15	0.7	− 0.04	− 0.14;0.07		0.084	− 0.02;0.19		− 0.12	− 0.3;0.01

Nicotine exposure	N	%	Multivariable
			sFlt-1				PlGF				sFlt-1/ PlGF-ratio
			Β	95% CI	P	Pinteraction	Β	95% CI	P	Pinteraction	Β	95% CI	P	Pinteraction
Snus	2090				0.157	0.116			0.020	0.031			0.271	0.233
Never (Ref.)	1622	77.6
Stopped before pregnancy	313	15.0	0.00	− 0.02;0.03			− 0.03	− 0.05;0.00			0.03	0.00;0.06
Stopped when recognized pregnancy	143	6.8	− 0.02	− 0.06;0.01			− 0.03	− 0.06;0.01			0.004	− 0.04;0.05
Current	12	0.6	− 0.11	− 0.20;0.01			− 0.12	− 0.20;0.00			0.007	− 0.14;0.15
Smoke	2200				0.530	0.552			0.248	0.104			0.228	0.361
Never (Ref.)	1702	77.3
Stopped before pregnancy	388	17.6	− 0.01	− 0.03;0.01			− 0.00	− 0.03;0.02			− 0.008	− 0.04;0.02
Stopped when recognized pregnancy	95	4.3	− 0.02	− 0.06;0.02			− 0.02	− 0.06;0.03			− 0.005	− 0.06;0.05
Current	15	0.7	− 0.03	− 0.14;0.07			0.1	− 0.06;0.20			− 0.13	− 0.3;(− 0.003)

Uni- and multivariable linear regression analyses on log transformed biomarker concentrations. Multivariable linear regression analyses are adjusted for fetal sex, gestational age, maternal age, prepregnancy BMI and parity (N = 2200). Global p-values are shown
B, beta coefficient; CI, confidence interval, N, number; P, global p-value; Pinteraction, interaction term between fetal sex and snus use on biomarker levels; PlGF, Placental Growth Factor; Ref., reference group; sFlt-1, Soluble Fms-like tyrosine kinase receptor 1

ISSN: 2042-6410