Table 3.

Subgroup analysis of risk for psoriasis according to presence of AD

	Atopic subgroups	Total, n	Psoriasis	Follow-up durationa	Incidence rateb	HR (95% CI)	p value
Age groups
≥20 and <40 years, n (%)	Non-AD group	1,236,850	26,867	10,168,335	2.64	1 (reference)	<0.01
	Mild	6,433	342	51,919	6.58	2.64 (2.37–2.93)
	Moderate-to-severe	11,361	754	91,110	8.27	3.28 (3.05–3.52)
≥40 and <65 years, n (%)	Non	1,855,567	49,626	15,179,366	3.26	1 (reference)
	Mild	9,012	533	72,534	7.34	2.28 (2.09–2.48)
	Moderate-to-severe	13,625	747	109,793	6.80	2.13 (1.98–2.28)
≥65 years, n (%)	Non	811,771	28,308	6,325,815	4.47	1 (reference)
	Mild	5,902	432	44,708	9.66	2.12 (1.93–2.34)
	Moderate-to-severe	7,401	574	55,388	10.36	2.30 (2.12–2.50)
Sex
Male	Non	2,150,871	60,651	17,354,350	3.49	1 (reference)	<0.01
	Mild	9,528	711	74,055	9.60	2.58 (2.40–2.78)
	Moderate-to-severe	14,706	1,170	114,291	10.23	2.88 (2.72–3.06)
Female	Non	1,753,317	44,150	14,319,166	3.08	1 (reference)
	Mild	11,819	596	95,107	6.26	2.05 (1.89–2.22)
	Moderate-to-severe	17,681	905	142,000	6.37	2.14 (2–2.28)
BMI
<25 kg/m2	Non	2,627,674	68,003	21,302,663	3.192	1 (reference)	0.10
	Mild	14,460	856	114,692	7.463	2.35 (2.2–2.52)
	Moderate-to-severe	22,457	1,419	177,557	7.99	2.58 (2.45–2.72)
≥25 kg/m2	Non	1,276,514	36,798	10,370,854	3.54	1 (reference)
	Mild	6,887	451	54,469	8.27	2.25 (2.05–2.46)
	Moderate-to-severe	9,930	656	78,734	8.33	2.35 (2.17–2.54)
Smoking history
Nonsmoker and ex-smoker	Non	2,876,241	75,582	23,375,933	3.23	1 (reference)	<0.01
	Mild	17,507	1,024	139,168	7.35	2.25 (2.12–2.4)
	Moderate-to-severe	25,563	1,528	202,971	7.52	2.39 (2.27–2.51)
Current smoker	Non	1,027,947	29,219	8,297,583	3.52	1 (reference)
	Mild	3,840	283	29,994	9.43	2.58 (2.29–2.90)
	Moderate-to-severe	6,824	547	53,320	10.25	2.91 (2.68–3.17)
Drinking
<30 g/day	Non	3,593,046	95,782	29,163,151	3.28	1 (reference)	0.27
	Mild	20,154	1,234	159,639	7.72	2.33 (2.20–2.46)
	Moderate-to-severe	30,339	1,918	240,279	7.98	2.48 (2.37–2.6)
≥30 g/day	Non	311,142	9,019	2,510,365	3.59	1 (reference)
	Mild	1,193	73	9,523	7.66	2.09 (1.66–2.63)
	Moderate-to-severe	2,048	157	16,012	9.80	2.78 (2.38–3.26)
Regular physical activity
Vigorous-moderate	Non	3,197,016	84,995	25,920,982	3.27	1 (reference)	0.39
	Mild	17,296	1,025	137,090	7.47	2.27 (2.13–2.41)
	Moderate-to-severe	26,583	1,679	210,247	7.98	2.5 (2.38–2.62)
Mild-none	Non	707,172	19,806	5,752,534	3.44	1 (reference)
	Mild	4,051	282	32,072	8.79	2.49 (2.21–2.8)
	Moderate-to-severe	5,804	396	46,044	8.60	2.53 (2.29–2.79)
Diabetes mellitus
Yes	Non	3,565,574	93,681	29,020,425	3.22	1 (reference)	0.33
	Mild	18,937	1,130	151,016	7.48	2.32 (2.19–2.46)
	Moderate-to-severe	29,838	1,890	236,981	7.97	2.53 (2.42–2.648)
No	Non	338,614	11,120	2,653,091	4.19	1 (reference)
	Mild	2,410	177	18,146	9.75	2.27 (1.96–2.64)
	Moderate-to-severe	2,549	185	19,310	9.58	2.26 (1.95–2.61)
Hypertension
Yes	Non	2,857,579	72,408	23,347,082	3.10	1 (reference)	0.07
	Mild	14,575	859	116,929	7.34	2.42 (2.26–2.59)
	Moderate-to-severe	23,865	1,449	190,753	7.59	2.54 (2.41–2.67)
No	Non	1,046,609	32,393	8,326,434	3.89	1 (reference)
	Mild	6,772	448	52,233	8.57	2.13 (1.94–2.34)
	Moderate-to-severe	8,522	626	65,537	9.55	2.43 (2.25–2.63)
Dyslipidemia
Yes	Non	3,198,556	83,063	25,983,230	3.19	1 (reference)	0.31
	Mild	16,790	994	133,449	7.44	2.35 (2.20–2.5
	Moderate-to-severe	26,075	1,625	206,925	7.85	2.54 (2.42–2.67)
No	Non	705,632	21,738	5,690,286	3.82	1 (reference)
	Mild	4,557	313	35,712	8.76	2.21 (1.98–2.47)
	Moderate-to-severe	6,312	450	49,366	9.11	2.38 (2.16–2.61)

CI, confidence interval; HR, hazard ratio.

^aFollow-up duration is in person-years.

^bIncidence rate is presented as 1,000 person-years.