Table 3.

Association of frequency of playing cards/mahjong with dementia after further exclusions.

Frequency of playing cards/mahjong	Incidence density per 1,000 persons-years	Unadjusted model HR (95% CI)	P value	Age-and sex-adjusted model HR (95% CI)	P value	Multivariable-adjusted model* HR (95% CI)	P value
Excluding participants who were MMSE scores < 18 at baseline
Rarely or never	12.4 (11.3–13.6)	Ref		Ref		Ref
Sometimes a	8.4 (5.7–12.2)	0.60 (0.42–0.87)	0.008	0.83 (0.57–1.20)	0.132	0.72 (0.41–1.27)	0.146
Regularly b	7.7 (4.8–12.0)	0.58 (0.38–0.90)	0.013	0.75 (0.49–1.16)	0.138	0.61 (0.34–1.11)	0.094
almost everyday	6.6 (4.3–10.1)	0.47 (0.31–0.71)	<0.001	0.62 (0.41–0.94)	0.011	0.54 (0.36–0.97)	0.021
Further excluding participants who suffer from epilepsy or stroke at baseline
Rarely or never	12.0 (10.8–13.1)	Ref		Ref		Ref
Sometimes a	7.8 (5.3–11.4)	0.57 (0.39–0.84)	0.006	0.80 (0.54–1.19)	0.132	0.73 (0.40–1.32)	0.326
Regularly b	7.6 (4.8–11.9)	0.59 (0.38–0.92)	0.014	0.77 (0.49–1.21)	0.137	0.69 (0.38–1.26)	0.294
almost everyday	6.7 (4.4–10.1)	0.48 (0.32–0.74)	<0.001	0.65 (0.43–0.98)	0.031	0.60 (0.29–1.22)	0.308
Excluding dementia that occurred during the first year of follow-up
Rarely or never	12.0 (11.0–13.1)	Ref		Ref		Ref
Sometimes a	7.9 (5.5–11.4)	0.74 (0.50–1.10)	0.105	1.05 (0.70–1.56)	0.096	0.90 (0.48–1.68)	0.279
Regularly b	7.1 (4.5–11.2)	0.68 (0.42–1.10)	0.107	0.89 (0.55–1.45)	0.073	0.69 (0.32–1.50)	0.236
almost everyday	5.1 (3.2–8.0)	0.48 (0.30–0.79)	0.004	0.65 (0.40–1.05)	0.066	0.63 (0.31–1.31)	0.195

HR, hazard ratio; CI, Confidence interval. Sometimes ^a: at least once for a month; Regularly ^b: at least once for a week. Multivariable-adjusted model^* including age, sex, education, household income, marital status, smoking status, drinking status, exercise, BMI, living with family members, hypertension, diabetes, and MMSE score.