Determinants of generalized anxiety and construction of a predictive model in patients with chronic obstructive pulmonary disease

Table 1 Comparison of clinical data between modeling and validation groups

Category	MO groups (n = 190)	VA groups (n = 81)	χ2/t	P value
Age (years)
18-60	28	13	0.247	0.619
> 60	122	68
Gender
Male	118	52	0.106	0.744
Female	72	29
BMI (kg/m²)	22.35 ± 1.81	22.09 ± 1.94	1.059	0.290
Educational level
Junior high school and below	57	24	0.912	0.634
Technical/vocational or high school	112	51
College and above	21	6
Marital status
Married	151	64	0.007	0.932
Unmarried, divorced, or widowed	39	17
Average household income, CNY
< 3000	98	42	0.627	0.731
3000-5000	62	29
> 5000	30	10
Living arrangement
Living alone	19	9	0.799	0.671
Living with spouse	126	56
Living with children or others	45	26
Smoking history
Yes	55	22	0.089	0.765
No	135	59
Smoking index, cigarettes/year
≥ 400	92	38	0.052	0.820
< 400	98	43
Alcohol history
Yes	36	14	0.104	0.747
No	154	67
COPD duration (years)
< 5	44	19	0.724	0.696
5-10	59	29
> 10	87	33
GOLD Stage
Stage 1	13	6	1.233	0.745
Stage 2	84	39
Stage 3	54	24
Stage 4	39	12
Acute exacerbations in the past year
0 or 1 time	104	41	0.387	0.534
≥ 2 times	86	40
FEV1 (L)	1.29 ± 0.45	1.17 ± 0.58	1.837	0.067
Cardiovascular comorbidities
Yes	76	31	0.020	0.889
No	118	50
Home oxygen therapy
Yes	29	13	0.470	0.493
No	118	68
Understanding of the disease
Completely unaware	27	12	1.770	0.413
Moderately aware	127	59
Very aware	36	10
Personality
Introverted	116	47	0.217	0.641
Extroverted	74	34
GAD
Yes	49	18	0.041	0.840
No	141	63

BMI: Body mass index; COPD: Chronic obstructive pulmonary disease; GOLD: Global Initiative for Chronic Obstructive Lung Disease; FEV₁: Forced expiratory volume in the first second; GAD: Generalized anxiety disorder; MO: Modeling group; VA: Validation group; CNY: China yuan.

Table 2 Comparison of clinical data between generalized anxiety disorder and non-generalized anxiety disorder groups

Category	GAD group (n = 49)	Non-GAD group (n = 141)	χ2/t	P value
Age (yeas)
18-60	8	20	0.133	0.716
> 60	41	121
Gender
Male	31	87	0.038	0.846
Female	18	54
BMI (kg/m²)	21.97 ± 1.95	22.34 ± 1.87	1.180	0.239
Educational level
Junior high school and below	24	33	12.452	0.002
Technical/vocational or high school	23	89
College and above	2	19
Marital status
Married	37	114	0.636	0.425
Unmarried, divorced, or widowed	12	27
Average household income, CNY
< 3000	24	74	7.039	0.030
3000-5000	22	40
> 5000	3	27
Living arrangement
Living alone	5	14	0.106	0.949
Living with spouse	32	94
Living with children or others	12	31
Smoking history
Yes	21	34	6.211	0.013
No	28	107
Smoking index, cigarettes/year
≥ 400	32	60	7.538	0.006
< 400	17	81
Alcohol history
Yes	9	27	0.014	0.904
No	40	114
COPD duration (years)
< 5	11	33	0.080	0.961
5-10	16	43
> 10	22	65
GOLD Stage
Stage 1	3	10	0.259	0.968
Stage 2	22	62
Stage 3	13	41
Stage 4	11	28
Acute exacerbations in the past year
0 or 1 time	17	87	10.711	0.001
≥ 2 times	32	54
FEV1 (L)	1.19 ± 0.36	1.28 ± 0.41	1.364	0.174
Cardiovascular comorbidities
Yes	30	46	9.966	0.002
No	19	85
Home oxygen therapy
Yes	8	21	0.058	0.810
No	41	120
Understanding of the disease
Completely unaware	21	6	49.452	< 0.001
Moderately aware	27	100
Very aware	1	35
Personality
Introverted	39	75	10.561	0.001
Extroverted	10	66

BMI: Body mass index; COPD: Chronic obstructive pulmonary disease; GOLD: Global Initiative for Chronic Obstructive Lung Disease; FEV₁: Forced expiratory volume in the first second; GAD: Generalized anxiety disorder; CNY: China yuan.

Table 3 Multifactorial logistic regression analysis for the development of generalized anxiety disorder in the modeling group

Factors	β	SE	Ward χ2	P value	OR	95%CI
Educational level (junior high school and below)	1.198	0.451	7.061	0.009	3.315	1.370-8.024
Average household monthly income (< 3000 CNY)	0.832	0.339	6.024	0.014	2.298	1.182-4.466
Smoking history	0.650	0.274	5.632	0.019	1.916	1.120-3.278
Smoking index (≥ 400 cigarettes/year)	0.633	0.282	5.045	0.024	1.884	1.084-3.274
Acute exacerbations in the past year (≥ 2 times)	1.295	0.368	12.389	< 0.001	3.652	1.775-7.512
Presence of cardiovascular comorbidities	1.047	0.415	6.365	0.010	2.849	1.263-6.426
Understanding of the disease (completely unaware)	0.986	0.433	5.187	0.021	2.681	1.147-6.264
Personality (introverted type)	0.848	0.309	7.539	0.005	2.336	1.275-4.281

OR: Odds ratio; CNY: China yuan.