Table 3.

Four-way mediation analysis decomposition for racialized disparities in incident dementia using elevated levels of C-reactive protein (CRP ≥4.73 μg/mL) as a mediator

	Incident dementia*
	Minoritized racial group vs non-Hispanic white N = 6908				non-Hispanic Black vs non-Hispanic white N = 6275				Hispanic vs non-Hispanic white N = 6095
Mediator (CRP)	Estimate	[95%CI]	[95%CI]	p value	Estimate	[95%CI]	[95%CI]	p value	Estimate	[95%CI]	[95%CI]	p value
Excess risk
RERI Controlled Direct Effect	1.26	0.91	1.67	<0.00	1.60	1.15	2.21	<0.00	0.94	0.48	1.51	<0.00
RERI Interaction Reference	0.16	0.01	0.32	0.04	0.06	−0.14	0.26	0.66	0.39	0.10	0.71	0.01
RERI Interaction Mediation	0.04	0.00	0.08	0.04	0.02	−0.06	0.11	0.66	−0.02	−0.09	0.06	0.82
RERI Pure Indirect Effect	0.01	0.00	0.02	0.23	0.01	0.00	0.04	0.13	0.00	−0.01	0.01	0.85
% Attributable
% Controlled Direct Effect	0.86	0.73	0.99	<0.00	0.95	0.78	1.10	<0.00	0.72	0.49	0.92	<0.00
% Interaction Reference	0.11	0.00	0.22	0.04	0.03	−0.08	0.15	0.66	0.30	0.07	0.52	0.01
% Interaction Mediation	0.03	0.00	0.06	0.04	0.01	−0.04	0.07	0.66	−0.02	−0.07	0.05	0.82
% Pure Indirect Effect	0.00	0.00	0.01	0.23	0.01	0.00	0.02	0.13	0.00	−0.01	0.01	0.85
Percent Mediated	0.03	0.00	0.06	0.01	0.02	−0.03	0.08	0.42	−0.02	−0.08	0.05	0.82
Percent due to Interaction	0.14	0.01	0.27	0.04	0.04	−0.11	0.21	0.66	0.28	0.08	0.51	0.01
Percent Eliminated	0.14	0.01	0.27	0.03	0.05	−0.10	0.22	0.55	0.28	0.08	0.51	0.01

^*Outcome 6-year incident dementia, model adjusting for age, sex, education categories, APOE-ε4 allele status, wave, smoking status, alcohol consumption, body mass index, and chronic conditions. Minoritized racial group: (non-Hispanic Black and Hispanic participants)

Models are stratified by minoritized status and racialized social groups in a sample of United States adults in the Health and Retirement Study