Table 2.

Interaction effects of CRAR parameters and APOE ε4 status on incident dementia

			Multiplicative interaction	Additive interaction
CRARs	APOE ε4 non‐carrier	APOE ε4 carrier	HR (95% CI) † ; P	RERI (95% CI) †	AP (95% CI) †	SI (95% CI) †
L5
Quarter 1–3	1.00 [Reference]	3.43 (2.78, 4.25); <0.001	1.32 (0.90, 1.93); 0.161	1.48 (0.27, 2.69)	0.29 (0.10, 0.49)	1.58 (1.11, 2.26)
Quarter 4	1.11 (0.84, 1.48); 0.467	5.03 (3.88, 6.51); <0.001
M10
>50	1.00 [Reference]	4.32 (2.86, 6.54); <0.001	0.84 (0.53, 1.33); 0.467	1.59 (0.05, 3.13)	0.23 (0.02, 0.45)	1.38 (0.98, 1.95)
≤50	1.85 (1.31, 2.63); <0.001	6.77 (4.79, 9.57); <0.001
Relative amplitude
Quarter 2–4	1.00 [Reference]	4.12 (3.26, 5.22); <0.001	0.80 (0.56, 1.15); 0.231	1.86 (0.25, 3.46)	0.26 (0.08, 0.44)	1.43 (1.07, 1.92)
Quarter 1	2.15 (1.65, 2.80); <0.001	7.13 (5.46, 9.31); <0.001
L5 onset
Intermediate to delayed	1.00 [Reference]	3.84 (3.14, 4.68); <0.001	0.87 (0.57, 1.35); 0.539	0.19 (−1.13, 1.50)	0.04 (−0.25, 0.34)	1.06 (0.71, 1.59)
Advanced	1.29 (0.94, 1.76); 0.116	4.31 (3.19, 5.83); <0.001

Abbreviations: AP, attributable proportion due to interaction; APOE, apolipoprotein E; CI, confidence interval; CRAR, circadian rest‐activity rhythm; HR, hazard ratio; L5, the least active 5‐h period; M10, the most active 10‐h period; RERI, relative excess risk due to interaction; SI, the synergy index.

^† Multivariable Cox model was adjusted for age, sex, education level, ethnicity, Townsend index of deprivation, recruitment center, season of accelerometer wear, smoking status, alcohol intake, healthy diet score, obesity, history of diabetes, hypertension, depression, and APOE ε4 carrier.