Efficacy of Unsupervised Home-Based Pulmonary Rehabilitation for Patients with Chronic Obstructive Pulmonary Disease

Figures & data

Figure 1 Study design for unsupervised home-based pulmonary rehabilitation. Baseline measurements were obtained after enrolling eligible patients. The patients performed unsupervised home-based pulmonary rehabilitation after receiving 1-h education on it at baseline. The patients were called weekly and encouraged to achieve home-based pulmonary rehabilitation and maintain diaries of recordings. After 8 weeks, patients were categorized as either the compliant or noncompliant group, and measurements were analyzed for outcomes.

Table 1 Baseline Characteristics

	Total (N = 41)	Compliant Group (N = 26)	Noncompliant Group (N = 15)	P value
Male, n (%)*	37 (90.2)	25 (96.2)	12 (80.0)	0.130
Age (years)	68.73 ± 8.31	68.69 ± 9.34	68.80 ± 6.46	0.969
BMI (kg/m^2)	22.87 ± 3.07	22.96 ± 3.26	22.72 ± 2.83	0.809
Smoking, n (%)				0.089
Current	8 (19.5)	5 (19.2)	3 (20.0)
Ex-smoker	28 (68.3)	20 (76.9)	8 (53.3)
Never smoker	5 (12.2)	1 (3.8)	4 (26.7)
Smoking (pack*years)	45.16 ± 28.92	50.75 ± 29.35	35.47 ± 26.32	0.104
Comorbidity, n (%)
DM*	4 (9.8)	3 (11.5)	1 (6.7)	> 0.999
HTN*	9 (22.0)	3 (11.5)	6 (40.0)	0.053
Cardiovascular*	5 (12.2)	2 (7.7)	3 (20.0)	0.336
Malignancy*	8 (19.5)	5 (19.2)	3 (20.0)	> 0.999
History of acute exacerbation, n (%)				0.735
0	37 (90.2)	23 (88.5)	14 (93.3)
1	3 (7.3)	2 (7.7)	1 (6.7)
2	1 (2.4)	1 (3.8)	0 (0.0)
Drug compliance*	37 (90.2)	24 (92.3)	13 (86.7)	0.615
Pre CAT	16.49 ± 7.56	16.46 ± 7.80	16.53 ± 7.38	0.977
Pre mMRC, n (%)				0.367
2	28 (68.3)	16 (61.5)	12 (80.0)
3	7 (17.1)	6 (23.1)	1 (6.7)
4	6 (14.6)	4 (15.4)	2 (13.3)
Pre BODE index	3.68 ± 1.97	4.04 ± 1.93	3.07 ± 1.94	0.129
Pre Spirometry
FEV1 (L)	1.35 ± 0.51	1.32 ± 0.47	1.41 ± 0.58	0.595
FEV1% predicted	47.80 ± 16.69	46.15 ± 15.34	50.67 ± 19.01	0.411
FVC (L)	3.29 ± 0.82	3.38 ± 0.75	3.14 ± 0.94	0.361
FVC % predicted	81.76 ± 14.64	83.23 ± 14.24	79.20 ± 15.48	0.402
FEV1/FVC (%)	41.61 ± 13.00	38.89 ± 9.80	46.32 ± 16.54	0.128
FEF 25–75 (L)	0.46 ± 0.24	0.43 ± 0.19	0.53 ± 0.29	0.224
FEF 25–75 % predicted	19.88 ± 10.53	18.04 ± 8.69	23.07 ± 12.84	0.191
Pre 6MWT (m)	413.63 ± 89.71	400.35 ± 97.31	436.67 ± 72.03	0.216

Notes: Between-group differences were analyzed using the chi-square test, Fisher’s exact test, or independent two-sample t-test. *Variables were analyzed using Fisher’s exact test.

Abbreviations: 6MWT, 6-min walking test; BMI, body mass index; BODE index, the body mass index, airflow obstruction, dyspnea, and exercise capacity index; DM, diabetes mellitus; HTN, hypertension; CAT, chronic obstructive pulmonary disease assessment test; mMRC, modified Medical Research Council; FEF 25–75, forced expiratory flow from 25 to 75% of the vital capacity; FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity.

Figure 2 Study flow chart of the enrollment of patients with COPD for the unsupervised home-based pulmonary rehabilitation study. A total of 50 patients were screened for the study; of them, 9 patients were excluded. Among the enrolled 41 patients, 26 patients were grouped as compliant and 15 as noncompliant, based on adherence and nonadherence to 30-min exercise per day for at least 3 days per week, respectively.

Table 2 Changes in Clinical, Spirometry, and 6-Min Walking Test Outcomes from Baseline to 8 Weeks in Both Groups

	Compliant Group (N = 26)	Noncompliant Group (N = 15)	P value
CAT	−4.62 ± 4.61	2.40 ± 6.73	0.002
mMRC	−0.73 ± 0.83	−0.27 ± 0.88	0.183
BODE index	−1.00 ± 1.06	−0.20 ± 0.56	0.010
FEV1 (L)	0.05 ± 0.19 (5.50 ± 16.48%)*	−0.09 ± 0.16 (−4.65 ± 10.65%)*	0.019 (0.039)*
6MWT (m)	18.23 ± 43.96 (6.61 ± 13.79%)*	4.87 ± 46.25 (3.22 ± 17.09%)*	0.363 (0.492)*

Notes: Between-group differences were analyzed using the independent two-sample t-test. *Changed ratio as a reference for the baseline value.

Abbreviations: 6MWT, 6-min walking test; BODE index, the body mass index, airflow obstruction, dyspnea, and exercise capacity index; CAT, chronic obstructive pulmonary disease assessment test; mMRC, modified Medical Research Council; FEV₁, forced expiratory volume in 1 s.

Figure 3 Primary outcome and CAT changes after 8 weeks of home-based pulmonary rehabilitation. A scatter plot representing chronic obstructive pulmonary disease (COPD) assessment test (CAT) results at baseline and 8 weeks. The plot is presented as mean with 95% confidence interval (CI). The differences between baseline values and values obtained after 8 weeks were analyzed using an independent two-sample t-test. In the compliant group, CAT scores significantly improved (16.46 ± 7.80 vs 11.85 ± 7.23; P = 0.03), whereas in the noncompliant group, there was no significant change in CAT scores (16.53 ± 7.38 vs 18.93 ± 10.59; P = 0.48).

Figure 4 Secondary outcome measurements after 8 weeks of home-based pulmonary rehabilitation obtained for mMRC, BODE index, FEV₁, and 6MWT. The scatter plot presents baseline and 8 weeks outcomes. The plots are presented as mean with 95% confidence interval. Differences between the baseline values and values obtained after 8 weeks were analyzed using an independent two-sample t-test. In the compliant group, mMRC scores (2.54 ± 0.76 vs 1.81 ± 0.63; P = 0.001, (A)) significantly improved after 8 weeks. However, the BODE index (4.04 ± 1.93 vs 3.04 ± 1.97; P = 0.07, (B)), FEV1 (1.32 ± 0.47 vs 1.37 ± 0.46; P = 0.71, (C)), and 6MWT results (400.35 ± 97.31 vs 418.58 ± 88.07; P = 0.48, (D)) did not show significant changes. In the noncompliant group, mMRC scores (2.33 ± 0.72 vs 2.07 ± 0.80; P = 0.44, (A)), BODE index (3.07 ± 1.94 vs 2.87 ± 1.96; P = 0.78, (B)), FEV1 (1.41 ± 0.58 vs 1.31 ± 0.52; P = 0.66, (C)), and 6MWT results (436.67 ± 72.03 vs 441.53 ± 47.20; P = 0.83, (D)) were not significantly different.

Abbreviations: 6MWT, 6-min walking test; BODE index, the body mass index, airflow obstruction, dyspnea, and exercise capacity index; FEV₁, forced expiratory volume in 1 s; mMRC, modified Medical Research Council.