Table 1. Demographic characteristics of study population.

	Comparison n = 13, 948	Psoriatic disease n = 3, 487	p value
Age	45.43 ± 19.62	45.28 ± 19.52	0.6782
Sex			0.4145
Female	5,391 (38.65%)	1,374 (39.40%)
Male	8,557 (61.35%)	2,113 (60.60%)
Co-morbidities
COPD	486 (3.48%)	143 (4.10%)	0.0808
Diabetes	1,369 (9.82%)	336 (9.64%)	0.7499
Hypertension	2,658 (19.06%)	651 (18.67%)	0.6020
Hyperlipidemia	1,270 (9.11%)	311 (8.92%)	0.7317
Frequency of dental visit within 365 days prior to index date			0.2996
0	9,481 (67.97%)	2,313 (66.33%)
1	1,707 (12.24%)	457 (13.11%)
2	988 (7.08%)	259 (7.43%)
≧3	1,772 (12.7%)	458 (13.13%)
Type of psoriatic disease
Psoriasis	–	3,072 (88.10%)
Psoriatic arthritis	–	415 (11.90%)