Life quality among psoriasis patients based on Dermatology Life Quality Index evaluation and its association with psoriasis severity in China: a cross-sectional study

Figures & data

Table 1. The demographic feature of psoriasis patients in China, 2020–2021.

Variables	Total psoriasis patients (n = 4230)	Patient with different gender		p
		Male patient (n = 2734)	Female patient (n = 1496)
Age (years)^a, median (IQR)	37.5 (30.0–50.9)	38.4 (30.0–51.1)	35.8 (28.7–50.4)	.000
Age (years)^a, n (%)				.002
<30	1049 (24.8)	632 (23.1)	417 (27.9)
30–39	1317 (31.1)	855 (31.3)	462 (30.9)
40–49	745 (17.6)	513 (18.8)	232 (15.5)
≥50	1119 (26.5)	734 (26.9)	385 (25.7)
Marital status, n (%)				.587
Unmarried	1051 (24.9)	672 (24.6)	379 (25.3)
Married	3179 (75.1)	2062 (75.4)	1117 (74.7)
Education^a, n (%)				.006
Junior high and lower	1320 (31.2)	807 (29.5)	513 (34.3)
Senior high	1419 (33.6)	936 (34.2)	483 (32.3)
College and above	1491 (35.3)	991 (36.3)	500 (33.4)
BMI (kg/m^2)^a, median (IQR)	23.9 (21.6–26.6)	24.3 (22.3–26.9)	22.9 (20.6–25.6)	.000
BMI (kg/m^2)^a, n (%)				.000
<18.5 (lower body weight)	180 (4.3)	58 (2.1)	122 (8.2)
18.5–23.9 (normal body weight)	1999 (47.3)	1199 (43.9)	800 (53.5)
24.0–27.9 (overweight)	1329 (31.4)	992 (36.3)	337 (22.5)
≥28 (obesity)	722 (17.1)	485 (17.7)	237 (15.8)
Regions^a, n (%)				.001
Northeast of China	516 (12.2)	296 (10.8)	220 (14.7)
East of China	789 (18.7)	554 (20.3)	235 (15.7)
North of China	1157 (27.4)	759 (27.8)	398 (26.6)
Middle of China	714 (16.9)	455 (16.6)	259 (17.3)
South of China	591 (13.9)	380 (13.9)	211 (14.1)
Southwest of China	162 (3.8)	99 (3.6)	63 (4.2)
Northwest of China	301 (7.1)	191 (6.9)	110 (7.4)
Medical insurance, n (%)				.894
Yes	4115 (97.3)	2659 (97.3)	1456 (97.3)
No	115 (2.7)	75 (2.7)	40 (2.7)
Smoking status^a, n (%)				.000
Non-smokers	2840 (67.1)	1424 (52.1)	1416 (94.7)
Smokers	1390 (32.9)	1310 (47.9)	80 (5.3)

IQR: interquartile range.

^a The difference between male and female patients was statistically significant (p < .05).

Table 2. The psoriasis severity, family history, seasonality aggravation and skin damage condition among psoriasis patients in China, 2020–2021.

Variables	Total patients (n = 4230)	Male patients (n = 2734)	Female patients (n = 1496)	P
PASI score^a, (median, IQR)	7.2 (3.0–13.5)	8.2 (3.6–14.8)	5.5 (2.4–12.2)	.001
PASI score^a, n (%)				.000
<3	1040 (24.6)	565 (20.7)	475 (31.8)
3–7	1073 (25.4)	687 (25.1)	386 (25.8)
8–11	728 (17.2)	478 (17.5)	250 (16.7)
≥12	1389 (32.8)	1004 (36.7)	385 (25.7)
Psoriasis severity (erythema/infiltration/scales) (median, IQR)
Head and neck total score^a	3.0 (0.0–6.0)	3.0 (1.0–6.0)	3.0 (0.0–6.0)	.000
Trunk total score^a	4.0 (2.0–6.0)	5.0 (2.0–6.0)	4.0 (0.0–6.0)	.000
Upper limb total score^a	4.0 (2.0–6.0)	4.0 (3.0–6.0)	3.0 (2.0–6.0)	.000
Lower limb total score^a	5.0 (3.0–6.0)	6.0 (3.0–7.0)	4.0 (3.0–6.0)	.000
Seasons of psoriasis aggravation, n (%)
Spring	682 (16.1)	427 (15.6)	255 (17.1)	.228
Summer	329 (7.9)	229 (8.4)	100 (6.7)	.050
Autumn	886 (20.9)	571 (20.9)	315 (21.1)	.896
Winter^a	1987 (46.9)	1327 (48.5)	660 (44.1)	.006
Types of psoriasis, n (%)
Psoriasis vulgaris	3945 (93.3)	2552 (93.3)	1393 (93.1)	.777
Psoriasis erythroderma^a	140 (3.3)	106 (3.9)	34 (2.3)	.005
Psoriasis arthritis	117 (2.8)	82 (3.0)	35 (2.3)	.211
Localized herpetic psoriasis^a	87 (2.1)	44 (1.6)	43 (2.9)	.006
Generalized herpetic psoriasis	59 (1.4)	34 (1.2)	25 (1.7)	.257
Family history of psoriasis patients, n (%)				.415
Yes	669 (15.8)	414 (15.1)	255 (17.1)
No	3153 (74.5)	2062 (75.4)	1091 (72.9)
Unknown	408 (9.7)	258 (9.4)	150 (10.0)

IQR: interquartile range.

^a The differences between male and female psoriasis patients were statistically significant (p < .05).

Figure 1. The proportion of responses to each 10 items in Dermatology Life Quality Index (DILQ) among psoriasis patients in China.

Table 3. The life quality among psoriasis patients based on Dermatology Life Quality Index (DLQI) evaluation in China, 2020–2021.

Variables	DLQI scores (n = 4230)	DLQI scores by group (n, %)
		0–1 (n = 671)	2–5 (n = 937)	6–10 (n = 1253)	>10 (n = 1369)
Age (years), median (IQR)
<30	7 (3–12)	164 (15.6)	265 (25.3)	288 (27.5)	332 (31.7)
30–39	9 (3–13)	198 (15.0)	265 (20.1)	395 (29.9)	459 (34.9)
40–49	8 (3–12)	113 (15.2)	165 (22.2)	221 (29.7)	246 (33.0)
≥50	8 (3–12)	196 (17.5)	242 (21.6)	349 (31.2)	332 (29.7)
Gender^a, median (IQR)
Male	8 (3–13)	442 (16.2)	570 (20.9)	810 (29.6)	912 (33.4)
Female	7 (3–12)	229 (15.3)	367 (24.5)	443 (29.6)	457 (30.6)
Marital status, median (IQR)
Unmarried	8 (3–13)	150 (14.3)	254 (24.2)	292 (23.3)	355 (33.8)
Married	8 (3–12)	521 (16.4)	683 (21.5)	961 (30.2)	1014 (31.9)
Education, median (IQR)
Junior high and lower	8 (3–12)	231 (17.5)	272 (20.6)	396 (30.0)	421 (31.9)
Senior high	8 (3–13)	215 (15.2)	319 (22.5)	408 (28.8)	477 (33.6)
College and above	8 (3–12)	225 (15.1)	346 (23.2)	449 (30.1)	471 (31.6)
BMI (kg/m^2), median (IQR)
<18.5 (lower body weight)	6 (3–11)	29 (16.1)	47 (26.1)	58 (32.2)	46 (25.6)
18.5–23.9 (normal body weight)	8 (3–12)	329 (16.5)	441 (22.1)	591 (29.6)	638 (31.9)
24.0–27.9 (overweight)	8 (3–12)	206 (15.5)	292 (21.9)	396 (29.8)	435 (32.7)
≥28 (obesity)	8 (3–14)	107 (14.8)	157 (21.8)	208 (28.8)	250 (34.6)
Medical insurance, median (IQR)
Yes	8 (3–13)	651 (15.8)	906 (22.0)	1214 (29.5)	1344 (32.7)
No	6 (3–13)	20 (17.4)	31 (26.9)	39 (33.9)	25 (21.7)
Smoking status, median (IQR)
Non-smokers	8 (3–12)	450 (15.9)	625 (22.0)	861 (30.3)	904 (31.8)
Smokers	8 (3–13)	221 (15.9)	312 (22.5)	392 (28.2)	465 (33.5)
PASI score^a, median (IQR)
<3	4.5 (1–9)	286 (27.5)	289 (27.8)	268 (25.8)	197 (18.9)
3–7	8 (3–11)	177 (16.5)	261 (24.3)	333 (31.0)	302 (28.2)
8–11	9 (4–13)	82 (11.3)	159 (21.8)	217 (29.8)	270 (37.1)
≥12	9 (5–16)	126 (9.1)	228 (16.4)	435 (31.3)	600 (43.2)

IQR: interquartile range.

^a The difference between male and female patients was statistically significant (p < .05).

Table 4. The percentage of DLQI score >10 and potential influencing factors of the higher DLQI score among psoriasis patients in China, 2020–2021.

Variables	Percentage of DLQI score >10, n (%)	Model 1		Model 2
		OR	95% CI	OR	95% CI
Age (years), median (IQR)
<30	332 (31.7)	1.00	–	1.00	–
30–39	459 (34.9)	1.16	0.97–1.37	1.08	0.90–1.29
40–49	246 (33.0)	1.07	0.87–1.30	0.93	0.75–1.14
≥50	332 (29.7)	0.91	0.76–1.09	0.76	0.63–0.92
Gender, median (IQR)
Male	912 (33.4)	1.00	–	1.00	–
Female	457 (30.6)	0.88	0.77–1.01	0.97	0.83–1.14
BMI (kg/m^2), median (IQR)
<18.5 (lower body weight)	46 (25.6)	1.00	–	1.00	–
18.5–23.9 (normal body weight)	638 (31.9)	1.37	0.96–1.93	1.35	0.94–1.94
24.0–27.9 (overweight)	435 (32.7)	1.42	1.00–2.02	1.35	0.93–1.96
≥28 (obesity)	250 (34.6)	1.54	1.07–2.23	1.47	1.01–2.16
Medical insurance, median (IQR)
Yes	25 (21.7)	1.00	–	1.00	–
No	1344 (32.7)	1.74	1.12–2.73	1.76	1.12–2.78
PASI score, median (IQR)
<3	197 (18.9)	1.00	–	1.00	–
3–7	302 (28.2)	1.68	1.37–2.06	1.69	1.38–2.08
8–11	270 (37.1)	2.52	2.03–3.13	2.61	2.10–3.25
≥12	600 (43.2)	3.25	2.70–3.93	3.36	2.78–4.07

OR: odds ratio; CI: confidence interval; IQR: interquartile range; PASI: psoriasis severity and severity index; DLQI: Dermatology Life Quality Index.

Model 1: univariate logistic regression; model 2: multivariate logistic regression.

Figure 2. The association between PASI score and DLQI score by gender and by age among patients in China.

Data availability statement

The data for this study are available upon request from the corresponding author. The request should state the title and aim of the research for which the data are requested.