Clinical and Psychological Impact of Chronic Pain in People with Chronic Obstructive Pulmonary Disease

Figures & data

Table 1 Participant Demographics

Demographic	COPD Group, n = 68	Control Group, n = 65	p value
Gender, male (%)	52 (76)	21 (32)	0.000
Age (years)	77 ± 9	78 ± 8	0.922
Height (cm)	160.2 ± 9.8	154.0 ± 10.2	0.001
Weight (kg)	53.6 ± 12.1	53.8 ± 11.8	0.949
BMI (kg/m^2)	20.8 ± 3.6	22.6 ± 3.4	0.003
Prevalence of pain (%)	58 (85)	33 (51)	0.000

Note: Data are presented as mean ± SD or number (%).

Abbreviations: COPD, chronic obstructive pulmonary disease; BMI, body mass index.

Figure 1 Flow diagram of study participants.

Abbreviation: COPD, chronic obstructive pulmonary disease.

Figure 2 Pain location.

COPD group,

Control group.*p<0.05 indicates a significant difference between groups.

Abbreviations: COPD, chronic obstructive pulmonary disease; UL, upper limb; LL, lower limb.

Table 2 Comparison of Characteristics Between the COPD and Control Group with Chronic Pain

Variables	COPD Group (n = 58)	Control Group (n = 33)	p value
Gender, male (%)	44 (76)	10 (30)	0.000
Age (years)	79 ± 9	80 ± 8	0.219
Height (cm)	156.6 ± 0.1	153.4 ± 0.1	0.186
Weight (kg)	50.8 ± 12.5	53.6 ± 11.8	0.041
BMI (kg/m^2)	20.3 ± 3.8	22.7 ± 3.1	0.004
Number of pain locations (n)	3.3 ± 2.5	1.7 ± 0.9	0.000
Pain intensity	4.1 ± 2.0	4.5 ± 1.9	0.679
Spirometry
FVC (L)	1.95 ± 0.81	–	–
FVC %pred (%)	71 ± 22	–	–
FEV1 (L)	1.06 ± 0.63	–	–
FEV1%pred (%)	49 ± 23	–	–
FEV1/FVC (%)	53 ± 20	–	–
GOLD Grade I/II/III/IV (n)	10/17/18/13	–	–
mMRC dyspnea scale
0/1/2/3/4 (n)	3/16/11/14/14	–
LTOT (%)	35 (60)	–	–
PCS-J
Rumination	9.5 ± 5.2	6.3 ± 5.6	0.087
Helplessness	6.3 ± 4.6	2.6 ± 3.3	0.006
Magnification	4.0 ± 3.7	1.6 ± 1.9	0.018
Total	19.5 ± 12.5	10.4 ± 9.9	0.019
≥30 (%)	16 (28)	3 (9)	0.025
TSK-J	37.8 ± 6.2	34.0 ± 5.8	0.033
≥37 (%)	39 (67)	14 (42)	0.028
HADS
Anxiety	5.5 ± 4.4	3.8 ± 3.3	0.112
≥8 (%)	17 (29)	6 (18)	0.041
Depression	9.6 ± 4.5	4.7 ± 2.9	0.219
≥8 (%)	25 (43)	7 (21)	0.008
Physical activity (steps/day)	1965 ± 1028	3813 ± 1804	0.012
Sleep duration (hours/day)	6.9 ± 1.3	7.1 ± 1.8	0.953

Note: Data are presented as mean ± SD or number (%).

Abbreviations: COPD, chronic obstructive pulmonary disease; BMI, body mass index; FVC, forced vital capacity; FEV₁, forced expiratory volume in 1 second; GOLD, Global Initiative for Chronic Obstructive Lung Disease; mMRC, modified Medical Research Council; LTOT, long-term oxygen therapy; PCS-J, the Japanese version of the Pain Catastrophizing Scale; TSK-J, the Japanese version of the Tampa Scale for Kinesiophobia; HADS, Hospital Anxiety and Depression Scale.

Table 3 Clinical Impact of Pain in Participants with COPD

Variables	Pain (n = 58)	No Pain (n = 10)	p value
Gender, male (%)	44 (76)	8 (80)	0.672
Age (years)	77 ± 9	78 ± 12	0.746
Height (cm)	157.8 ± 0.1	158.5 ± 0.1	0.744
Weight (kg)	50.8 ± 12.5	53.9 ± 11.1	0.931
BMI (kg/m^2)	20.3 ± 3.8	21.1 ± 2.6	0.493
Spirometry
FVC (L)	1.95 ± 0.81	2.33 ± 0.99	0.302
FVC %pred (%)	71 ± 22	78 ± 25	0.101
FEV1 (L)	1.06 ± 0.63	1.40 ± 0.57	0.198
FEV1%pred (%)	49 ± 23	60 ± 17	0.141
FEV1/FVC (%)	54 ± 20	63 ± 15	0.171
GOLD Grade I/II/III/IV (n)	10/17/18/13	1/6/3/1	0.007
mMRC dyspnea scale
0/1/2/3/4 (n)	3/16/11/14/14	5/1/3/1/0	0.001
LTOT (%)	35 (60)	4 (40)	0.032
NRADL (points)
Movement speed	17.9 ± 6.8	20.1 ± 8.3	0.027
Dyspnea	21.9 ± 7.3	24.5 ± 4.1	0.074
Supplemental oxygen	20.3 ± 5.3	26.5 ± 3.3	0.163
Total	70.0 ± 25.0	84.9 ± 9.1	0.016
6MWD (m)	333 ± 130	393 ± 168	0.011
Physical activity (steps/day)	1965 ± 1028	2813 ± 915	0.008
HADS
Anxiety	5.5 ± 4.4	4.9 ± 4.4	0.584
≥8 (%)	17 (29)	4 (40)	0.109
Depression	9.6 ± 4.5	6.4 ± 5.2	0.654
≥8 (%)	25 (43)	4 (40)	0.763
Sleep duration (hours/day)	6.9 ± 1.3	6.8 ± 0.9	0.484

Note: Data are presented as mean ± SD or number (%).

Abbreviations: COPD, chronic obstructive pulmonary disease; BMI, body mass index; FVC, forced vital capacity; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; mMRC, modified Medical Research Council; LTOT, long-term oxygen therapy; NRADL, Nagasaki University Respiratory Activities of Daily Living questionnaire; 6MWD, 6-min walk distance; HADS, Hospital Anxiety and Depression Scale.