Table 3.

Univariate and multivariate Cox proportional hazards models for variables associated with suicide and accidental death in study patients

Variable	HR (95% CI)
	Suicide death		Accidental death
	Univariate	Multivariate	Univariate	Multivariate
Total dementia
Age, yearsa	4.24 (0.58–31.28)	5.14 (0.69–38.50)	2.31 (1.07–4.99)†	2.21 (1.04–4.68)†
Occupational status
Yes	Reference	Reference	Reference	Reference
No	2.76 (1.16–6.51)†	3.71 (1.54–8.95)†	2.06 (1.19–3.59)†	2.09 (1.20–3.63)†
Education, yearsa	0.96 (0.88–1.03)	0.96 (0.89–1.03)	1.00 (0.97–1.05)	1.01 (0.98–1.05)
Clinical neuropsychiatric scores
K-MMSEb	1.02 (0.84–1.06)	1.01 (0.95–1.09)	1.00 (0.96–1.05)	0.99 (0.96–1.03)
S-IADLa	0.98 (0.95–1.03)	0.99 (0.95–1.02)	1.02 (1.01–1.04)†	1.06 (1.01–1.08)†
K-NPIa	1.88 (0.86–4.15)	1.01 (0.99–1.03)	1.01 (1.00–1.02)†	1.00 (0.99–1.01)
Mild cognitive impairment
Age, yearsa	1.07 (0.03–3.27)	1.07 (0.35–3.25)	3.81 (1.02–12.74)†	3.63 (1.12–11.79)†
Occupational status
Yes	reference	reference	reference	reference
No	0.99 (0.13–3.21)	0.96 (0.32–2.90)	0.79 (0.33–1.89)	0.76 (0.34–1.73)
Education, yearsa	0.90 (0.82–0.99)†	0.90 (0.81–0.99)†	1.07 (1.01–1.13)†	1.01 (1.00–1.13)†
Clinical neuropsychiatric scores
K-MMSEb	1.04 (0.88–1.20)	1.04 (0.91–1.19)	1.03 (1.00–1.15)†	1.05 (0.95–1.15)
S-IADLa	0.99 (0.89–1.10)	0.97 (0.87–1.07)	1.10 (1.02–1.14)†	1.08 (1.03–1.12)†
K-NPIa	0.94 (0.91–1.05)	0.99 (0.94–1.05)	1.01 (1.00–1.05)†	1.02 (1.00–1.05)†

Abbreviation: CI confidence interval, HR Hazard ratio, K-MMSE Korean Mini-Mental State Examination, K-NPI Korean version of Neuropsychiatric Inventory, S-IADL Seoul Instrumental Activity of Daily Living

^†The hazard ratio was significant (p < 0.05)

^aThe hazard ratio is for each 1-year increase in age or 1-point increase in clinical scores

^bThe hazard ratio is for each 1-point decrease in clinical scores