Construction and validation of a risk prediction model for depressive symptoms in a middle-aged and elderly arthritis population

Table 1 Fundamental demographic and clinical characteristics, n (%)

	Non-depression (n = 3288)	Depression (n = 2923)	Total (N = 6211)	P value
Gender				< 0.001
Male	1595 (48.5)	1033 (35.3)	2628 (42.3)
Female	1693 (51.5)	1890 (64.7)	3583 (57.7)
Marital status				< 0.001
Married	2847 (86.6)	2372 (81.1)	5219 (84.0)
Unmarried	441 (13.4)	551 (18.9)	992 (16.0)
Residence				< 0.001
Urban	1287 (39.1)	829 (28.4)	2116 (34.1)
Rural	2001 (60.9)	2094 (71.6)	4095 (65.9)
Age (year), mean ± SD	63.3 ± 9.38	63.5 ± 9.03	63.4 ± 9.22
Median (min, max)	63.0 (45.0, 95.0)	64.0 (45.0, 94.0)	64.0 (45.0, 95.0)
Education				< 0.001
Below primary	1349 (41.0)	1594 (54.5)	2943 (47.4)
Secondary school	943 (28.7)	740 (25.3)	1683 (27.1)
Middle school	642 (19.5)	425 (14.5)	1067 (17.2)
High school and above	354 (10.8)	164 (5.6)	518 (8.3)
Nighttime sleep duration (hour)				< 0.001
mean ± SD	6.28 ± 1.90	5.42 ± 2.17	5.88 ± 2.07
Median (min, max)	6.00 (0, 15.0)	5.00 (0, 20.0)	6.00 (0, 20.0)
Health status				< 0.001
Excellent	308 (9.4)	94 (3.2)	402 (6.5)
Rather or relatively good	382 (11.6)	136 (4.7)	518 (8.3)
General	1786 (54.3)	1238 (42.4)	3024 (48.7)
Mediocre	668 (20.3)	1065 (36.4)	1733 (27.9)
Bad	144 (4.4)	390 (13.3)	534 (8.6)
ADL-6				< 0.001
Not-difficult	2708 (82.4)	1809 (61.9)	4517 (72.7)
Difficult	580 (17.6)	1114 (38.1)	1694 (27.3)
No. of chronic diseases	2.96 (1.72)	3.61 (1.98)	3.26 (1.88)	< 0.001
Median (min, max)	3.00 (1.00, 12.0)	3.00 (1.00, 13.0)	3.00 (1.00, 13.0)
Hypertensive				< 0.001
Yes	1338 (40.7)	1338 (45.8)	2676 (43.1)
No	1950 (59.3)	1585 (54.2)	3635 (56.9)
Diabetes				< 0.001
Yes	434 (13.2)	496 (17.0)	930 (15.0)
No	2854 (86.8)	2427 (83.0)	5281 (85.0)
Tobacco use				< 0.001
Yes	886 (26.9)	647 (22.1)	1533 (24.7)
No	2402 (73.1)	2276 (77.9)	4678 (75.3)
Alcohol abuse				< 0.001
Yes	1178 (35.8)	804 (27.5)	1982 (31.9)
No	2110 (64.2)	2119 (72.5)	4229 (68.1)
Retired				< 0.001
Yes	548 (16.7)	259 (8.9)	807 (13.0)
No	2740 (83.3)	2664 (91.1)	5404 (87.0)
Audiological				< 0.001
Excellent	55 (1.7)	30 (1.0)	85 (1.4)
Very good	413 (12.6)	213 (7.3)	626 (10.1)
Good	586 (17.8)	371 (12.7)	957 (15.4)
General	1783 (54.2)	1709 (58.5)	3492 (56.2)
Bad	451 (13.7)	600 (20.5)	1051 (16.9)
Exercise				0.084
Yes	3040 (92.5)	2657 (90.9)	5697 (91.7)
No	248 (7.5)	266 (9.1)	514 (8.3)
Medical insurance				0.201
Yes	3211 (97.7)	2833 (96.9)	6044 (97.3)
No	77 (2.3)	90 (3.1)	167 (2.7)
Old-age insurance				0.961
Yes	2135 (64.9)	1888 (64.6)	4023 (64.8)
No	1153 (35.1)	1035 (35.4)	2188 (35.2)
No. of painful sites	3.42 (3.70)	5.89 (4.42)	4.58 (4.24)	< 0.001
Median (min, max)	2.00 (0, 15.0)	5.00 (0, 15.0)	4.00 (0, 15.0)

P values < 0.05 were considered statistically significant. ADL: Activities of daily living.