Table 4.

Factors for injury stratified by variables listed in the table using Cox regression

Stratified	People with dementia			People without dementia			Ratio	Adjusted HR	95% CI	p value
	Event	PYs	Rate (per 105 PYs)	Event	PYs	Rate (per 105 PYs)
Total	18,148	142,971.64	12,693.43	68,748	596,593.59	11,523.42	1.102	1.070	1.052–1.087	< 0.001
Gender
Male	9435	73,875.94	12,771.41	34,625	314,976.08	10,992.90	1.162	1.104	1.078–1.129	< 0.001
Female	8713	69,095.70	12,610.05	34,123	281,617.51	12,116.79	1.041	1.032	1.008–1.057	0.009
Age group (years)
50–64	1531	9815.95	15,597.06	5860	43,124.98	13,588.41	1.148	1.164	1.100–1.232	< 0.001
65–74	3400	20,642.92	16,470.54	11,866	81,240.04	14,606.10	1.128	1.092	1.051–1.135	< 0.001
75–84	8185	59,944.66	13,654.26	31,122	255,921.18	12,160.78	1.123	1.080	1.054–1.107	< 0.001
≧85	5032	52,568.11	9572.34	19,900	216,307.39	9199.87	1.040	1.012	0.981–1.044	0.455
Catastrophic illness
Without	14,846	111,309.27	13,337.61	56,572	471,309.04	12,003.16	1.111	1.065	1.045–1.084	< 0.001
With	3302	31,662.37	10,428.78	12,176	125,284.55	9718.68	1.073	1.118	1.076–1.163	< 0.001
Injury outpatient/ER 1 year before index date
Without	10,585	51,095.49	20,716.11	41,104	209,544.31	19,615.90	1.056	1.055	1.033–1.078	< 0.001
With	7563	91,876.15	8231.73	27,644	387,049.28	7142.24	1.153	1.093	1.065–1.121	< 0.001

Adjusted for comorbidities (diabetes mellitus, hypertension, hyperlipidemia, cerebrovascular disease, chronic kidney disease, alcohol-related disease)

CI confidence interval, ER emergency room, HR hazard ratio, PYs person-years