1. The overall prevalence of depression and anxiety in CTD patients
Among the 352 CTD patients enrolled in this study, the prevalence of depression (PHQ-9 score ≥ 5) and anxiety (GAD-7 score ≥ 5) was higher than that of the general population in China both during and before the COVID-19 pandemic, with the prevalence of depression was 44.3%, 32.2%, and 3.6%, respectively, and the prevalence of anxiety was 39.5%, 22.3%, and 5.0%, respectively. Furthermore, the prevalence of moderate and severe depression (PHQ-9 score ≥ 10) and moderate and severe anxiety (GAD-7 score ≥ 10) also increased significantly in CTD patients compared with that of the general population in China during the COVID-19 pandemic (17.0% vs 10.5% and 13.4% vs 6.4%, respectively) (Supplementary table S1).
2. Risk factors of depression in overall CTD patients
Firstly, univariate analysis was conducted for all the variables measured in this study between CTD patients with depression and those without depression (non-depression). As presented in Table 1, sleep time, gender, presence of comorbid CTDs, presence of anti-Ro52, anti-ribosomal P protein, anti-SSA and anti-SSB antibodies, serum level of complement C3, and presence of ILD or PAH were significantly different between the two groups (P < 0.05), while age, disease duration, comorbidity with other chronic diseases such as thyroid disease and diabetes, presence of other autoantibodies including APS, anti-RNP/Sm and anti-CENP-B, ESR, CRP, and serum levels of complement C4 and IgG showed no significant difference (P > 0.05).
Table 1
Univariate analysis of demographic, clinical and laboratory parameters between CTD patients with or without depression
|
Non-depression (n = 196)
|
Depression (n = 156)
|
Total
|
p value
|
Age
|
56.5(16.7)
|
57.7(13.9)
|
57.0 (15.5)
|
0.651
|
Disease duration (year)
|
7.8 (10.8)
|
7.6 (10.0)
|
7.7 (10.4)
|
0.730
|
Education time (year)
|
8.5 (4.5)
|
8.8 (4.3)
|
8.6 (4.4)
|
0.665
|
Sleep (hour)
|
6.4 (1.3)
|
5.7 (1.6)
|
6.1 (1.5)
|
< .0001
|
Gender
|
|
|
|
0.034
|
Male
|
39 (19.9)
|
18 (11.5)
|
57 (16.2)
|
|
Female
|
157 (80.1)
|
138 (88.5)
|
295 (83.8)
|
|
Marital status
|
|
|
|
0.486
|
Unmarried
|
35 (17.9)
|
25 (16)
|
60 (17)
|
|
Married/Divorced or widowed
|
161 (82.1)
|
130 (83.3)
|
291 (82.7)
|
|
Comorbid illness
|
|
|
|
|
Other CTDs
|
|
|
|
0.007
|
Yes
|
24 (12.2)
|
36 (23.1)
|
60 (17)
|
|
No
|
172 (87.8)
|
120 (76.9)
|
292 (83)
|
|
Thyroid disease
|
|
|
|
0.578
|
Yes
|
38 (19.4)
|
34 (21.8)
|
72 (20.5)
|
|
No
|
158 (80.6)
|
122 (78.2)
|
280 (79.5)
|
|
Diabetes
|
|
|
|
0.494
|
Yes
|
24 (12.2)
|
23 (14.7)
|
47 (13.4)
|
|
No
|
172 (87.8)
|
133 (85.3)
|
305 (86.6)
|
|
Other chronic diseases
|
|
|
|
0.663
|
Yes
|
81 (42.2)
|
69 (44.5)
|
150 (43.2)
|
|
No
|
111 (57.8)
|
86 (55.5)
|
197 (56.8)
|
|
Anti-Ro52
|
|
|
|
< .0001
|
(+)
|
42 (21.4)
|
100 (64.1)
|
142 (40.3)
|
|
(-)
|
154 (78.6)
|
56 (35.9)
|
210 (59.7)
|
|
aPLs
|
|
|
|
0.845
|
(+)
|
14 (7.1)
|
12 (7.7)
|
26 (7.4)
|
|
(-)
|
182 (92.9)
|
144 (92.3)
|
326 (92.6)
|
|
Anti-Rib-P
|
|
|
|
0.013
|
(+)
|
14 (7.1)
|
24 (15.4)
|
38 (10.8)
|
|
(-)
|
182 (92.9)
|
132 (84.6)
|
314 (89.2)
|
|
Anti-SSA
|
|
|
|
0.007
|
(+)
|
46 (23.5)
|
57 (36.5)
|
103 (29.3)
|
|
(-)
|
150 (76.5)
|
99 (63.5)
|
249 (70.7)
|
|
Anti-SSB
|
|
|
|
0.001
|
(+)
|
8 (4.1)
|
22 (14.1)
|
30 (8.5)
|
|
(-)
|
188 (95.9)
|
134 (85.9)
|
322 (91.5)
|
|
Anti-RNP/Sm
|
|
|
|
0.417
|
(+)
|
22 (11.2)
|
22 (14.1)
|
44 (12.5)
|
.
|
(-)
|
174 (88.8)
|
134 (85.9)
|
308 (87.5)
|
|
Anti-CENP-B
|
|
|
|
0.760
|
(+)
|
17 (8.7)
|
15 (9.6)
|
32 (9.1)
|
|
(-)
|
179 (91.3)
|
141 (90.4)
|
320 (90.9)
|
|
ILD
|
|
|
|
0.011
|
Yes
|
36 (18.5)
|
47 (30.1)
|
83 (23.6)
|
|
No
|
159 (81.5)
|
109 (69.9)
|
268 (76.4)
|
|
PAH
|
|
|
|
0.010
|
Yes
|
18 (9.2)
|
29 (18.6)
|
47 (13.4)
|
|
No
|
178 (90.8)
|
127 (81.4)
|
305 (86.6)
|
|
ESR (mm/h)
|
54.18 (42.55)
|
60.76 (42.13)
|
57.03 (42.43)
|
0.095
|
CRP (mg/L)
|
20.56 (33.50)
|
20.55 (34.63)
|
20.56 (33.96)
|
0.457
|
C3 (g/L)
|
0.82 (0.23)
|
0.75 (0.21)
|
0.79 (0.221)
|
0.007
|
C4 (g/L)
|
0.38 (2.45)
|
0.28 (1.15)
|
0.33 (1.98)
|
0.427
|
IgG (g/L)
|
14.71 (8.31)
|
15.34 (6.50)
|
14.99 (7.55)
|
0.182
|
Sleep time, gender, presence of comorbid CTDs, presence of anti-Ro52, anti-ribosomal P protein, anti-SSA and anti-SSB antibodies, serum level of complement C3, and presence of ILD or PAH were significantly different between the two groups (P < 0.05). CTD, connective tissue disease; aPLs, antiphospholipid antibodies; ILD, interstitial lung disease; PAH, pulmonary arterial hypertension; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein.
Then, in order to determine the independent risk factors of depression, the variables found to be statistically significant in the univariate analysis were included in the multivariate logistic regression analysis. The results showed that sleep time was a protective factor (OR = 0.719, 95% CI: 0.605 ~ 0.856, P = 0.0002) while anti-Ro52 antibody was a risk factor (OR = 5.545, 95% CI: 3.053 ~ 10.074, P < 0.001) (Table 2).
Table 2
Multivariate logistic regression analysis of parameters with statistical significance in the univariate analysis for CTD patients with depression
|
S.E
|
p value
|
OR
|
95%CI
|
|
Lower limit
|
Upper limit
|
Sleep time
|
0.088
|
0.0002
|
0.719
|
0.605
|
0.856
|
Gender
|
0.181
|
0.204
|
0.632
|
0.311
|
1.284
|
Comorbid with other CTDs
|
0.340
|
0.170
|
1.595
|
0.818
|
3.107
|
Anti-Ro52
|
0.305
|
< .0001
|
5.545
|
3.053
|
10.074
|
Anti-Rib-P
|
0.460
|
0.171
|
1.879
|
0.762
|
4.632
|
Anti-SSA
|
0.358
|
0.0780
|
0.534
|
0.265
|
1.078
|
Anti-SSB
|
0.533
|
0.082
|
2.529
|
0.889
|
7.193
|
ILD
|
0.311
|
0.540
|
1.210
|
0.658
|
2.223
|
PAH
|
0.390
|
0.188
|
1.672
|
0.778
|
3.593
|
C3
|
0.651
|
0.616
|
0.721
|
0.201
|
2.584
|
Sleep time was a protective factor while anti-Ro52 antibody was a risk factor for depression in CTD patients. CTD, connective tissue disease; ILD, interstitial lung disease; PAH, pulmonary arterial hypertension.
3. Risk factors of anxiety in overall CTD patients
Univariate analysis was conducted for all the variables measured in this study between CTD patients with anxiety and those without (non-anxiety). Sleep time, comorbidity with other CTDs, presence of anti-Ro52, anti-SSA and anti-SSB antibodies, serum level of complement C3 and IgG, and presence of ILD or PAH were significantly different between the two groups (P < 0.05) (Table 3).
Table 3
Univariate analysis of demographic, clinical and laboratory parameters between CTD patients with or without anxiety
|
Non-anxiety (N = 213)
|
Anxiety
(N = 139)
|
Total
|
p value
|
Age (year)
|
56.5 (16.7)
|
57.8 (13.5)
|
57 (15.5)
|
0.809
|
Disease duration (year)
|
8.1 (11.2)
|
7.1 (9.0)
|
7.7 (10.4)
|
0.995
|
Education time (year)
|
8.6 (4.5)
|
8.7 (4.2)
|
8.6 (4.4)
|
0.851
|
Sleep time (hour)
|
6.5 (1.4)
|
5.5 (1.4)
|
6.1 (1.5)
|
< .0001
|
Gender
|
|
|
|
0.456
|
Male
|
37 (17.4)
|
20 (14.4)
|
57 (16.2)
|
|
Female
|
176 (82.6)
|
119 (85.6)
|
295 (83.8)
|
|
Marital status
|
|
|
|
0.457
|
Unmarried
|
37 (17.4)
|
23 (16.5)
|
60 (17)
|
|
Married/Divorced or widowed
|
176 (82.6)
|
115 (82.7)
|
291 (82.7)
|
|
Comorbid illness
|
|
|
|
|
Other CTDs
|
|
|
|
0.016
|
Yes
|
28 (13.1)
|
32 (23)
|
60 (17)
|
|
No
|
185 (86.9)
|
107 (77)
|
292 (83)
|
|
Thyroid disease
|
|
|
|
0.132
|
Yes
|
38 (17.8)
|
34 (24.5)
|
72 (20.5)
|
|
No
|
175 (82.2)
|
105 (75.5)
|
280 (79.5)
|
|
Diabetes
|
|
|
|
0.254
|
Yes
|
32 (15)
|
15 (10.8)
|
47 (13.4)
|
|
No
|
181 (85)
|
124 (89.2)
|
305 (86.6)
|
|
Other chronic diseases
|
|
|
|
0.787
|
Yes
|
92 (43.8)
|
58 (42.3)
|
150 (43.2)
|
|
No
|
118 (56.2)
|
79 (57.7)
|
197 (56.8)
|
|
Anti-Ro52
|
|
|
|
< .0001
|
(+)
|
48 (22.5)
|
94 (67.6)
|
142 (40.3)
|
|
(-)
|
165 (77.5)
|
45 (32.4)
|
210 (59.7)
|
|
aPLs
|
|
|
|
0.911
|
(+)
|
16 (7.5)
|
10 (7.2)
|
26 (7.4)
|
|
(-)
|
197 (92.5)
|
129 (92.8)
|
326 (92.6)
|
|
Anti-Rib-P
|
|
|
|
0.293
|
(+)
|
20 (9.4)
|
18 (12.9)
|
38 (10.8)
|
|
(-)
|
193 (90.6)
|
121 (87.1)
|
314 (89.2)
|
|
Anti-SSA
|
|
|
|
0.001
|
(+)
|
48 (22.5)
|
55 (39.6)
|
103 (29.3)
|
|
(-)
|
165 (77.5)
|
84 (60.4)
|
249 (70.7)
|
|
Anti-SSB
|
|
|
|
0.0052
|
(+)
|
11 (5.2)
|
19 (13.7)
|
30 (8.5)
|
|
(-)
|
202 (94.8)
|
120 (86.3)
|
322 (91.5)
|
|
Anti-RNP/Sm
|
|
|
|
0.592
|
(+)
|
25 (11.7)
|
19 (13.7)
|
44 (12.5)
|
|
(-)
|
188 (88.3)
|
120 (86.3)
|
308 (87.5)
|
|
Anti-CENP-B
|
|
|
|
0.605
|
(+)
|
18 (8.5)
|
14 (10.1)
|
32 (9.1)
|
|
(-)
|
195 (91.5)
|
125 (89.9)
|
320 (90.9)
|
|
ILD
|
|
|
|
0.019
|
Yes
|
41 (19.3)
|
42 (30.2)
|
83 (23.6)
|
|
No
|
171 (80.7)
|
97 (69.8)
|
268 (76.4)
|
|
PAH
|
|
|
|
0.017
|
Yes
|
21 (9.9)
|
26 (18.7)
|
47 (13.4)
|
|
No
|
192 (90.1)
|
113 (81.3)
|
305 (86.6)
|
|
ESR (mm/h)
|
57.07 (42.89)
|
56.97 (41.83)
|
57.03 (42.43)
|
0.868
|
CRP (mg/L)
|
18.07 (29.19)
|
20.56 (33.96)
|
20.56 (33.96)
|
0.693
|
C3 (g/L)
|
0.82 (0.23)
|
0.75 (0.19)
|
0.79 (0.22)
|
0.005
|
C4 (g/L)
|
0.36 (2.35)
|
0.29 (1.22)
|
0.33 (1.98)
|
0.276
|
IgG (g/L)
|
14.08 (5.25)
|
16.39 (9.94)
|
14.99 (7.55)
|
0.005
|
Sleep time, comorbidity with other CTDs, presence of anti-Ro52, anti-SSA and anti-SSB antibodies, serum level of complement C3 and IgG, and presence of ILD or PAH were significantly different between the two groups (P < 0.05). CTD, connective tissue disease; aPLs, antiphospholipid antibodies; ILD, interstitial lung disease; PAH, pulmonary arterial hypertension; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein.
To determine the independent risk factors of anxiety, the variables found to be statistically significant in the univariate analysis were included in the multivariate logistic regression analysis. As a result, sleep time was a protective factor (OR = 0.639, 95% CI: 0.528 ~ 0.773, P < 0.0001) while anti-Ro52 antibody was a risk factor (OR = 5.642, 95% CI: 3.071 ~ 10.363, P < 0.0001) (Table 4).
Table 4
Multivariate logistic regression analysis of parameters with statistical significance in the univariate analysis for CTD patients with anxiety
|
S.E
|
p value
|
OR
|
95%CI
|
|
Lower limit
|
Upper limit
|
Sleep time
|
0.097
|
< .0001
|
0.639
|
0.528
|
0.773
|
Comorbid with other CTDs
|
0.348
|
0.413
|
1.329
|
0.672
|
2.629
|
Anti-Ro52
|
0.310
|
< .0001
|
5.642
|
3.071
|
10.363
|
Anti-SSA
|
0.354
|
0.818
|
0.922
|
0.460
|
1.846
|
Anti-SSB
|
0.508
|
0.911
|
1.059
|
0.391
|
2.867
|
ILD
|
0.316
|
0.852
|
1.061
|
0.571
|
1.970
|
PAH
|
0.403
|
0.308
|
1.507
|
0.685
|
3.318
|
C3
|
0.628
|
0.274
|
0.503
|
0.147
|
1.724
|
IgG
|
0.018
|
0.117
|
1.029
|
0.993
|
1.066
|
Sleep time was a protective factor while anti-Ro52 antibody was a risk factor for anxiety in CTD patients. CTD, connective tissue disease; ILD, interstitial lung disease; PAH, pulmonary arterial hypertension.
4. Risk factors of depression in different CTD subgroups
We divided the 352 CTD patients into four subgroups according to their main diagnosis: SLE, SS, RA, and other CTDs (including SSc, IIM and MCTD). Multivariate logistic regression analysis was performed for each group with the variables found to be statistically significant in the univariate analysis for overall CTD patients with depression as the independent variables and the presence of depression as the dependent variable. As a result, anti-Ro52 antibody was significantly different in all four subgroups and was a risk factor for depression in these CTD patients (OR = 3.579, 7.481, 7.054, and 7.441, respectively). Besides, Sleep time was shown to be a protective factor in SS and RA groups (OR = 0.549 and 0.356, respectively) while PAH was a risk factor in RA group (OR = 13.199). In contrast, anti-SSA was not statistically significant in either subgroup (Supplementary tables S2.1-S2.4).
5. Risk factors of anxiety in different CTD subgroups
Similarly, multivariate logistic regression analysis was performed for each group with the variables found to be statistically significant in the univariate analysis for overall CTD patients with anxiety as the independent variables and the presence of anxiety as the dependent variable. The results showed that anti-Ro52 antibody was significantly different in all four subgroups and was a risk factor for anxiety in patients with SLE, SS, RA and other CTDs (OR = 7.541, 5.375, 38.216, and 8.773, respectively). Meanwhile, Sleep time was shown to be a protective factor in SLE, SS and RA groups (OR = 0.582, 0.490, and 0.329, respectively), while serum level of complement C3 seemed to be a risk factor in RA group (OR = 1.006). In contrast, anti-SSA was not statistically significant in either subgroup (Supplementary tables S3.1-S3.4).
To eliminate possible deviation caused by the difference of demographic characteristics between each subgroup and overall CTD subjects, we also carried out univariate analysis of depression and anxiety for patients in each subgroup, and then took the parameters with statistical significance as independent variables and the presence of depression or anxiety as dependent variables for multivariate logistic regression analysis. Very similar results were obtained which showed that anti-Ro52 antibody, but not anti-SSA, was significantly different in each subgroup and was a risk factor for depression (OR = 3.243–9.220) and anxiety (OR = 4.833–12.302) (Supplementary tables S4.1-11.2). Furthermore, anti-SSA was not significantly related with depression and anxiety in overall CTD patients either (Table 2, 4).
6. Prevalence and severity of depression and anxiety in CTD patients with anti-Ro52 antibody
Finally, we analyzed the prevalence and severity of depression and anxiety in patients with anti-Ro52 antibody. The results showed that in both overall CTD patients and different disease subgroups, the prevalence of depression and anxiety in anti-Ro52 positive subjects increased significantly compared with that in anti-Ro52 negative ones (Table 5–6). Furthermore, the PHQ-9 and GAD-7 scores were markedly higher in patients with anti-Ro52 in comparison with those without, indicating a more severe condition in anti-Ro52 positive CTD patients (Table 7).
Table 5
Prevalence of depression in overall CTDs patients and different subgroups with or without anti-Ro52 antibody
|
Anti-Ro52
|
Depression (N, %)
|
Non-depression (N, %)
|
Prevalence
|
P
|
Overall CTDs
|
(+)
|
100 (64.1)
|
42 (21.4)
|
70.42%
|
< .000
|
|
(-)
|
56 (35.9)
|
154 (78.6)
|
26.67%
|
|
SLE
|
(+)
|
30 (65.2)
|
16 (34.8)
|
65.22%
|
0.004
|
|
(-)
|
16 (34.8)
|
30 (65.2)
|
34.78%
|
|
SS
|
(+)
|
47 (75.8)
|
16 (35.6)
|
74.60%
|
< .000
|
|
(-)
|
15 (24.2)
|
29 (64.4)
|
34.09%
|
|
RA
|
(+)
|
8 (36.4)
|
3 (7.1)
|
72.73%
|
0.003
|
|
(-)
|
14 (63.6)
|
39 (92.9)
|
26.43%
|
|
Other CTDs
|
(+)
|
15 (57.7)
|
7 (11.1)
|
68.18%
|
< .000
|
|
(-)
|
11 (42.3)
|
56 (88.9)
|
16.41%
|
|
In both overall CTD patients and different disease subgroups, the prevalence of depression in anti-Ro52 positive subjects increased significantly compared with that in anti-Ro52 negative ones (P < 0.05).
Table 6
Prevalence of anxiety in overall CTDs patients and different subgroups with or without anti-Ro52 antibody
|
Anti-Ro52
|
Anxiety (N, %)
|
Non-anxiety (N, %)
|
Prevalence
|
P
|
Overall CTDs
|
(+)
|
94 (67.6)
|
48 (22.5)
|
66.20%
|
< .000
|
|
(-)
|
45 (32.4)
|
165 (77.5)
|
21.43%
|
|
SLE
|
(+)
|
29 (69)
|
17 (34)
|
63.04%
|
0.001
|
|
(-)
|
13 (31)
|
33 (66)
|
28.26%
|
|
SS
|
(+)
|
44 (75.9)
|
19 (38.8)
|
69.84%
|
0.000
|
|
(-)
|
14 (24.1)
|
30 (61.2)
|
31.82%
|
|
RA
|
(+)
|
7 (53.8)
|
4 (7.8)
|
63.64%
|
< .000
|
|
(-)
|
6 (46.2)
|
47 (92.2)
|
11.32%
|
|
Other CTDs
|
(+)
|
14 (53.8)
|
8 (12.7)
|
63.64%
|
< .000
|
|
(-)
|
12 (46.2)
|
55 (87.3)
|
17.91%
|
|
In both overall CTD patients and different disease subgroups, the prevalence of anxiety in anti-Ro52 positive subjects increased significantly compared with that in anti-Ro52 negative ones (P < 0.05).
Table 7
Comparison of PHQ-9 and GAD-7 scores between CTD patients with or without anti-Ro52 antibody
|
Number
|
PHQ-9
|
t
|
P
|
GAD-7
|
t
|
P
|
Anti-Ro52
|
|
|
6.24
|
< .000
|
|
8.09
|
< .000
|
(+)
|
142
|
6.70 (4.57)
|
|
|
6.38 (4.93)
|
|
|
(-)
|
210
|
3.53 (4.75)
|
|
|
2.41 (3.82)
|
|
|
Total
|
352
|
4.81 (4.93)
|
|
|
4.01 (4.72)
|
|
|
The PHQ-9 and GAD-7 scores were markedly higher in patients with anti-Ro52 in comparison with those without (p < 0.05).