Outcomes of a telemonitoring-based program (telEPOC) in frequently hospitalized COPD patients

Figures & data

Figure 1 Flowchart of recruitment and follow-up process.

Table 1 Sociodemographic and clinical descriptive data

Variable	Hospital		Total 197	P-value
	H1 78 (39.6)	H2 119 (60.4)
Sex				0.9
Male	68 (87.2%)	103 (86.6%)	171 (86.8%)
Age, years	70.1 (7.5)	71.34 (9.36)	70.83 (8.83)	0.21
BMI	27.78 (5.05)	26.99 (4.8)	27.3 (4.9)	0.46
BMI				0.4
<25	23 (29.5%)	39 (32.8%)	62 (31.5%)
25–30	32 (41%)	55 (46.2%)	87 (44.2%)
>30	23 (29.5%)	25 (21%)	48 (24.4%)
Smoking status				0.5
Current smoker	12 (15.4%)	19 (16%)	31 (15.7%)
Ex-smoker	65 (83.3%)	96 (79.8%)	160 (81.2%)
Nonsmoker	1 (1.3%)	5 (4.2%)	6 (3.1%)
General health				0.01
Excellent	0	0	0 (0%)
Very good	2 (2.6%)	0	2 (1%)
Good	8 (10.3%)	28 (23.5%)	36 (18.3%)
Regular	46 (55%)	51 (42%)	96 (48.7%)
Bad	20 (25.6%)	41 (34.5%)	61 (31%)
Modified MRC dyspnea scale				0.02
0–1	28 (35.9%)	27 (22.7%)	55 (27.9%)
2	22 (28.2%)	48 (40.3%)	70 (35.5%)
3	8 (10.3%)	25 (21%)	33 (16.8%)
4	20 (25.6%)	19 (16%)	39 (19.8%)
Pulmonary function tests
FEV1 (%)	44.5 (15.1)	45.5 (15.7)	45.1 (15.4)	0.46
FVC (%)	74.3 (17.8)	72 (19.1)	72.9 (18.5)	0.34
Charlson Comorbidity Index	3.5 (2.1)	3.5 (1.7)	3.5 (1.9)	0.74
Charlson Comorbidity Index				0.66
1	14 (17.9%)	16 (13.4%)	30 (15.2%)
2	15 (19.2%)	22 (18.5%)	37 (18.8%)
>2	49 (62.8%)	81 (68.1%)	130 (66%)
BODE index	3.9 (2.2)	4.3 (2.5)	4.1 (2.4)	0.34

Note: Data expressed as n (%) or mean (standard deviation).

Abbreviations: H1, control group; H2, intervention group; BMI, body mass index; MRC, medical research council; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; BODE, body mass index, airflow obstruction, dyspnea, exercise capacity.

Table 2 Use of health care-resource outcomes: univariate analysis

Outcome variables	H1 (n=78)		H2 (n=119)		P-value
	Mean (95% CI)	Median (P25–P75)	Mean (95% CI)	Median (P25–P75)
COPD hospital admissions
Preintervention	3.9 (3.5–4.4)	3 (3–4)	3.4 (3.1–3.8)	3 (2–4)	0.03
Postintervention	2.8 (2.2–3.4)	2 (1–4)	1.1 (0.7–1.5)	0 (0–1)	<0.001
Pre- vs postintervention	1.1 (0.5–1.7)	2 (0–3)	2.3 (1.9–2.7)	2 (2–3)	<0.001
Trend P-value	<0.001		<0.001
COPD-related readmissions within 30 days¥
Preintervention	1.3 (0.9–1.7)	1 (0–2)	1.1 (0.7–1.4)	1 (0–1.5)	0.54
Postintervention	1.1 (0.7–1.5)	0 (0–1.5)	0.4 (0.1–0.7)	0 (0–0)	0.001
Pre- vs postintervention	0.2 (−0.3 to 0.8)	0 (−1 to 1)	0.7 (0.3–1.1)	1 (0–1)	0.09
Trend P-value	0.38		0.003
Visits to ED related to COPD exacerbation
Preintervention	0.8 (0.5–1)	0 (0–1)	1 (0.7–1.2)	1 (0–1)	0.09
Postintervention	0.9 (0.6–1.2)	0 (0–1)	0.6 (0.3–0.8)	0 (0–1)	0.02
Pre- vs postintervention	−0.1 (−0.1 to 0.2)	0 (−1 to 1)	0.4 (0.1–0.6)	0 (0–1)	0.006
Trend P-value	0.42		0.002
Cumulative total LOS¥
Preintervention	39.5 (31.6–7.3)	32.5 (20–46.5)	21.7 (16.2–27.1)	14 (8.5–26.5)	<0.001
Postintervention	34.1 (26.5–41.8)	24 (12–49)	14.7 (10.1–19.2)	7.5 (3.5–18.5)	<0.001
Pre- vs postintervention	−5.32 (−14.5 to 3.8)	−3.5 (−19 to 14.5)	−7 (–13.6 to 0.4)	−6 (−18 to 3)	0.56
Trend P-value	0.33		0.006

Note:

¥ Parameter calculated among patients with hospital admissions during the telEPOC program (n=60 in H1, n=56 in H2).

Abbreviations: CI, confidence interval; P₂₅, 25th percentile; P₇₅, 75th precentile; H1, control group; H2, intervention group; ED, emergency department; LOS, length of stay.

Table 3 Clinical outcomes: univariate analysis

Outcome variables	H1 (n=78)	H2 (n=119)	P-value
	Mean (95% CI)	Mean (95% CI)
SGRQ total (n=164)
Baseline	50.9 (46.6–55.3)	49.5 (46–53)	0.53
At end of telEPOC program	52.1 (47.5–56.6)	47 (43.4–50.6)	0.08
Difference	−1.15 (−5 to 2.7)	2.5 (−0.03 to 5)	0.07
Trend P-value	0.4	0.03
LCADL scale total (n=164)
Baseline	21.2 (18.1–24.3)	24.1 (21.8–26.5)	0.04
At end of telEPOC program	27.6 (23.9–31.3)	26.2 (23.5–28.8)	0.62
Difference	−6.4 (−10.1 to −2.7)	−2 (−3.5 to −0.6)	0.02
Trend P-value	<0.001	0.007
Six-minute walk test, m (n=182)
Baseline	352.84 (332.15–373.53)	311.14 (286.62–335.67)	0.26
At end of telEPOC program	302.87 (281.68–324.07)	305.47 (280.5–330.45)	0.2
Difference	−49.97 (−65.11 to −34.83)	−5.67 (−21.32 to 9.8)	<0.001
Trend P-value	<0.001	0.83
BODE index (n=182)
Baseline	3.6 (3.1–4.1)	4.3 (3.8–4.7)	0.12
At end of telEPOC program	4.1 (3.7–4.7)	4.3 (3.9–4.8)	0.99
Difference	0.6 (0.2–1)	0.03 (−0.3 to 0.3)	0.008
Trend P-value	0.004	0.78
HADS (n=165)
Baseline	4.6 (3.7–5.5)	6 (5.1–6.9)	0.04
At end of telEPOC program	5.6 (4.7–6.6)	6.1 (5.3–6.9)	0.51
Difference	−1.1 (−1.9 to −0.2)	−0.08 (−0.8 to 0.7)	0.06
Trend P-value	0.02	0.84
Death at end of telEPOC program			0.85
Yes, n (%)	13 (16.7%)	22 (18.5%)

Abbreviations: H1, control group; H2, intervention group; CI, confidence interval; HRQoL, health-related quality of life; SGRQ, St George’s Respiratory Questionnaire; LCADL, London Chest Activity of Daily Living; BODE, body mass index, airflow obstruction, dyspnea, exercise capacity; HADS, Hospital Anxiety and Depression Scale.

Table 4 Use of health care-resource outcomes: multivariate analysis

Model	β-estimate (SE)	IRR (95% CI)	P-value
COPD hospital admissions*
Intercept	−0.552 (0.848)	0.576 (0.109–3.033)	0.515
Hospital (H2 vs H1)	−0.962 (0.178)	0.382 (0.27–0.541)	<0.0001
BODE index	0.184 (0.038)	1.203 (1.117–1.295)	<0.0001
Previous COPD admissions	0.174 (0.042)	1.19 (1.097–1.292)	<0.0001
Visits to ED related to COPD*
Intercept	−1.246 (1.231)	0.288 (0.026–3.21)	0.311
Hospital (H2 vs H1)	−0.575 (0.248)	0.563 (0.346–0.916)	0.021
BODE index	0.04 (0.051)	1.041 (0.941–1.15)	0.438
Previous ED visits related to COPD	0.401 (0.091)	1.494 (1.251–1.784)	<0.0001
Cumulative total LOS**
Intercept	2.054 (0.199)	7.8 (5.279–11.526)	<0.0001
Hospital (H2 vs H1)	−0.545 (0.119)	0.58 (0.459–0.732)	<0.0001
BODE index	0.052 (0.026)	1.053 (1.002–1.107)	0.042
Previous cumulative LOS	0.001 (0.002)	1.001 (0.997–1.005)	0.758
COPD admissions during telEPOC program	0.263 (0.021)	1.301 (1.249–1.354)	<0.0001
Readmissions*
Intercept	−0.207 (1.098)	0.813 (0.094–7.002)	0.851
Hospital (H2 vs H1)	−0.775 (0.241)	0.461 (0.287–0.738)	0.001
BODE index	0.131 (0.052)	1.140 (1.03–1.262)	0.012
Previous readmissions	0.126 (0.051)	1.134 (1.026–1.253)	0.013
Readmissions within 30 days*
Intercept	−0.713 (1.624)	0.49 (0.02–11.827)	0.661
Hospital (H2 vs H1)	−1.361 (0.388)	0.256 (0.12–0.549)	<0.0001
BODE index	0.229 (0.082)	1.258 (1.072–1.476)	0.005
Previous readmissions within 30 days	0.123 (0.116)	1.131 (0.901–1.419)	0.288

Notes:

* Models adjusted by patient’s sex and age and Charlson Comorbidity Index;

** model adjusted by Charlson Comorbidity Index and HADS depression domain.

Abbreviations: SE, standard error; IRR, incidence-rate ratio; CI, confidence interval; H1, control group; H2, intervention group; BODE, body mass index, airflow obstruction, dyspnea, exercise capacity; ED, emergency department; LOS, length of stay; HADS, Hospital Anxiety and Depression Scale.

Table 5 Clinical outcomes: multivariate analysis of outcome change

	SGRQ		LCADL		6-Minute walking test
	β (SE)	P-value	β (SE)	P-value	β (SE)	P-value
Intercept	−15.342 (3.367)	0.001	−10.697 (1.998)	<0.0001	76.994 (37.325)	0.04
Baseline domain	0.337 (0.074)	<0.0001	0.36 (0.083)	<0.0001	−0.293 (0.071)	<0.0001
Hospital
H2 (intervention)	4.185 (2.077)	0.046	3.332 (1.644)	0.044	36.633 (11.756)	0.002
H1 (control)	Reference		Reference		Reference
BODE index	−0.763 (0.556)	0.172	−0.605 (0.416)	0.148	−6.591 (3.638)	0.072
Sex
Female	–	–	−6.962 (2.373)	0.004	–	–
Male	–	–	Reference		–	–
R^2	14.62%		16.32%		16.6%

Note: Positive β-estimate means improvement in HRQoL variables.

Abbreviations: SGRQ, St George’s Respiratory Questionnaire; LCADL, London Chest Activity of Daily Living; SE, standard error; H1, control group; H2, intervention group; BODE, body mass index, airflow obstruction, dyspnea, exercise capacity; HRQoL, health-related quality of life.

Table 6 Intention to treat analysis of the effect of the telEPOC program in the measured outcomes

	β (SE)	P-value
Use of health care-resource outcomes
COPD hospital admissions	−0.83 (0.17)	<0.001
Visits to ED related to COPD	−0.502 (0.242)	0.038
Accumulative total length of stay	−0.573 (0.114)	<0.001
Number of readmissions	−0.738 (0.236)	0.002
Number of readmissions within 30 days	−1.338 (0.387)	0.001
Clinical outcomes
SGRQ	3.93 (2.03)	0.055
LCADL	3.39 (1.62)	0.038
Six-minute walking test	49.82 (12.55)	0.0001

Notes: β (SE) estimates compare the telEPOC program arm and the control arm. A negative β-estimate in the use of health care resources means an improvement in the health care-resource outcome. Values from the previous 2 years were applied to participants lost to follow-up. A positive β-estimate in the changes in clinical outcome parameters means an improvement in the respective clinical outcome. Values from the baseline visit were applied to participants lost to follow-up.

Abbreviations: SE, standard error; ED, emergency department; SGRQ, St George’s Respiratory Questionnaire; LCADL, London Chest Activity of Daily Living.