Depression symptoms reduce physical activity in COPD patients: a prospective multicenter study

Figures & data

Figure 1 Approach to assess the effect of anxiety and depression (exposures) at t and physical activity (outcome) at t+1 adjusting for covariates and physical activity at t.

Table 1 Baseline sociodemographic, clinical, and functional characteristics of 220 COPD patients from five European sites

Baseline characteristics	All patients
	n=220
Age (years), m (SD)	67 (8)
Sex: male, n (%)	149 (68%)
Living alone, n (%)	108 (49%)
Socio-economic status:a low (IV and V), n (%)	30 (14%)
Active worker, n (%)	26 (12%)
Smoking status: current, n (%)	38 (17%)
Pack years, median (P25 to P75)	47 (31 to 72)
Any COPD exacerbation in the previous year, n (%)	88 (40%)
mMRC score, median (P25 to P75)	2 (1 to 2)
Number of chronic diseases (other than COPD), median (P25 to P75)	2 (1 to 3)
Cardiovascular disease,b n (%)	118 (54%)
Diabetes, n (%)	19 (9%)
Musculoskeletal diseases,c n (%)	48 (22%)
Osteoporosis,d n (%)	23 (10%)
Body mass index (kg/m^2), m (SD)	27 (5)
Fat free mass index (kg/m^2), m (SD)	18 (3)
FEV1 (% predicted), m (SD)	57 (20)
COPD severity stages
I – Mild (FEV1 ≥80%)	30 (14)
II – Moderate (FEV1 <80% and ≥50%)	101 (46)
III – Severe (FEV1 <50% and ≥30%)	69 (31)
IV – Very severe (FEV1 <30%)	20 (9)
RV/TLC (%), m (SD)	51 (11)
Six minutes walking distance test, m (SD)	423 (130)
CAT score (0 to 40), median (P25 to P75)	14 (8 to 21)
Probable anxiety (HADS-A ≥11), n (%)	23 (10%)
Probable depression (HADS-D ≥11), n (%)	12 (5%)

Notes:

a Socio-economic status was measured through the UK National Statistics Socio-economic classification.

b Cardiovascular disease was the presence of doctor-diagnosed diseases in medical records (ICD9 390–459).

c Musculoskeletal diseases included connective tissue diseases (ICD9 710–739).

d Osteoporosis included osteoporosis (ICD9 733.0) and osteopenia (ICD9 733.90).

Abbreviations: m, mean; SD, standard deviation; P25, 25th percentile; P75, 75th percentile; mMRC, Modified Medical Research Council Dyspnea Scale; FEV₁, forced expiratory volume in 1 second; RV/TLC, residual volume to total lung capacity ratio; CAT, COPD assessment test; HADS-A, Hospital Anxiety and Depression Scale-Anxiety; HADS-D, Hospital Anxiety and Depression Scale-Depression; ICD, International Classification of Diseases.

Figure 2 Distribution of steps and time in locomotion at t+1, according to categories of HADS-A and HADS-D at t.

Notes: (A) Steps at t+1 across HADS-A categories at t; (B) steps at t+1 across HADS-D categories at t; (C) time in locomotion t+1 months across HADS-A at t; and (D) time in locomotion at t+1 across HADS-D categories at t. HADS-A score: 0–7 normal, 8–10 suggested anxiety, and ≥11 probable anxiety. HADS normal, 8–10 suggested depression, and ≥11 probable depression.
Abbreviations: HADS-A, Hospital Anxiety and Depression Scale-anxiety; HADS-D, Hospital Anxiety and Depression Scale-Depression.

Table 2 Crude and adjusted associations between HADS-depression score at t and daily steps at t+1 (linear regression model)

Characteristics at t	Crudea		Adjusted
			Saturated modelb		Parsimonious modelc
	β (95% CI)	P-value	β (95% CI)	P-value	β (95% CI)	P-value
Constant	N/A	–	4,690 (4,323 to 5,058)	<0.01	4,733 (4,377 to 5,089)	<0.01
HADS-D (per each extra point)	−204 (−313 to −96)	<0.01	−70 (−141 to 0)	0.05	−81 (−149 to −12)	0.02
Age (per each extra year old)	−86 (−131 to −42)	<0.01	−15 (−50 to 19)	0.37	–	–
Six minutes walking distance test (6MWD, per each extra meter)	11 (8 to 13)	<0.01	1.7 (−0.8 to 4.2)	0.17	–	–
≥2 comorbidities	−984 (−1785 to −182)	0.01	−332 (−833 to 169)	0.19	−414 (−901 to 72)	0.09
FEV1 % predicted (per each extra percent unit)	42 (21 to 63)	<0.01	10 (−3 to 22)	0.13	11 (−0.8 to 23)	0.06
Steps/day at t (per each extra step)	0.7 (0.6 to 0.8)	<0.01	0.6 (0.5 to 0.8)	<0.01	0.6 (0.5 to 0.8)	<0.01

Notes:

a Each row is a single model.

b The column is a single model. The value of the constant is the number of steps at t+1 of a patient with mean HADS-D score, mean age, mean 6MWD, >2 comorbidities, mean FEV₁ (% predicted) and mean steps/day at t.

c The column is a single model. The value of the constant is the number of steps at t+1 of a patient with mean HADS-D score, <2 comorbidities, mean FEV₁ (% predicted) and mean baseline steps/day at t.

Abbreviations: CI, confidence interval; N/A, not applicable; HADS-D, Hospital Anxiety and Depression Scale-Depression; FEV₁, forced expiratory volume in 1 second.