Table 3.

Adjusted marginal structural models estimating controlled direct effects (CDE) of inflammatory markers (i.e., high-sensitivity C reactive protein (CRP), tumour necrosis factor (TNF), and Interleukin 6 (IL-6)) on diastolic blood pressure (DBP) measures in the presence and absence of vitamin D (VD) insufficiency [25(OH)D<50 nmol/L] among Indigenous Cree adults from the Multi-Community Environment-and-Health Study, 2005–2009

CDE DBP
	VD insufficiency present (m=1)		P value*	VD insufficiency absent (m=0)		P value*
	†E(Y(a, m(1) – Y(a*, m(1)))			†E(Y(a, m(0) – Y(a*, m(0))
	Estimate β	95% CI		Estimate β	95% CI
CRP
Model 1	2.04	−4.28 to 8.35	0.526	3.29	−0.71 to 7.31	0.107
Model 2	1.54	−4.73 to 7.82	0.630	3.24	−1.10 to 7.94	0.137
Model 3	0.69	−5.70 to 7.07	0.834	1.59	−2.69 to 5.89	0.466
TNF-α
Model 1	−5.08	−13.31 to 3.15	0.226	−2.29	−6.62 to 2.02	0.298
Model 2	−5.05	−13.24 to 3.15	0.228	−2.69	−6.92 to 1.52	0.210
Model 3	−5.25	−13.46 to 2.95	0.209	−2.53	−6.67 to 1.61	0.231
IL-6
Model 1	6.28	−3.32 to 15.88	0.199	3.33	−1.53 to 8.20	0.179
Model 2	6.40	−3.00 to 15.81	0.182	3.43	−1.44 to 8.30	0.167
Model 3	7.88	−3.74 to 19.52	0.184	2.51	−3.83 to 8.87	0.437

*Statistical significance (p<0.05)

†CDE for the each inflammatory marker exposure level indicating the average direct effect change on systolic blood pressure and DBP outcomes if the exposure is contrasted (ie, a=1, and a*=0), while uniformly fixing the intermediate variable (m) to either designated level, VD insufficiency or VD sufficiency (ie, m(1) and m(0), respectively) in the population. Model 1: age, sex; Model 2: model 1, plus smoking status; Model 3: model 2, plus body mass index.