Table 1. Demographic characteristics of pneumonia patients with and those without depressive disorder (DD) in Taiwan in 2005∼2011 (n = 14,364).

Variable	Patients with DD (n = 2,394)		Comparison group (n = 11,970)		p value
	Total no.	Percent (%)	Total No.	Percent (%)
Gender					1.000
Male	1,274	53.2	6,370	53.2
Female	1,120	46.8	5,600	46.8
Age (years)					1.000
18∼24	36	1.5	180	1.5
25∼34	85	3.6	425	3.6
35∼44	144	6.0	720	6.0
45∼54	206	8.6	1,030	8.6
55∼64	314	13.1	1,570	13.1
65∼74	471	19.7	2,355	19.7
≧75	1,138	47.5	5,690	47.5
Monthly income (US$)					<0.001
$1∼530	1,532	64.0	6,988	58.4
$530∼830	690	28.8	4,028	33.7
≥$830	172	7.2	954	8.0
Urbanization level					0.053
1 (most urbanized)	594	24.8	2,786	23.3
2	631	26.4	2,942	24.6
3	349	14.6	1,797	15.0
4	402	16.8	2,168	18.1
5 (least urbanized)	418	17.5	2,277	19.0
Geographic region					0.006
Northern	978	40.9	4,886	40.8
Central	543	22.7	3,010	25.2
Southern	795	33.2	3,618	30.3
Eastern	78	3.3	456	3.8
Charlson Comorbidity Index score					0.254
0	911	38.1	4,544	38.0
1	749	31.3	3,777	31.6
2	328	13.7	1,483	12.4
3	195	8.2	977	8.2
≥4	211	8.8	1,189	9.9