Implementation of a Telehealth Programme for Patients with Severe Chronic Obstructive Pulmonary Disease Treated with Long-Term Oxygen Therapy

Abstract

We conducted a pilot study of the effectiveness of home telehealth for patients with advanced chronic obstructive pulmonary disease treated with long-term oxygen therapy. Patients were randomized into a telehealth group (n = 24) and a control group (n = 21) who received usual care. Patients in the telehealth group measured their vital signs on weekdays and performed spirometry on two days per week. The data were transmitted automatically to a clinical call centre. After four months of monitoring the mean number of accident and emergency department visits in the telehealth group was slightly lower than in the control group (0.29 versus 0.43, P = 0.25). The mean number of hospital admissions was 0.38 in the telehealth group and 0.14 in the control group (P = 0.47). During the study a total of 40 alerts were detected. The clinical triage process detected eight clinical exacerbations which were escalated by the case manager for a specialist consultation. There were clinically important differences in health-related quality of life in both groups. The mean score on the SGRQ was 10.9 versus 4.5 in the control group (P = 0.53). The EuroQol-5D score improved by 0.036 in the telehealth group and by 0.003 in the control group (P = 0.68). Both patients and healthcare professionals showed a high level of satisfaction with the telehealth programme.

Introduction

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide, and results in an economic and social burden that is both substantial and increasing. COPD exacerbations account for the greatest proportion of the total COPD burden on the health care system. Estimates for costs related to exacerbations range from 35% to 84% of total direct costs attributable to COPD.¹ Several studies have detected a significant increase in mortality rate after hospitalisation.^2,3 Although it is logical to think that the main determinant of death after hospitalisation is baseline disease severity, recent studies have shown that exacerbations requiring hospital care are an adverse prognostic factor, regardless of baseline disease severity. That is, mortality increases significantly as the frequency and severity of exacerbations increase.⁴ Any action to manage exacerbations in these patients at an early stage may help to reduce morbidity and mortality, thereby reducing health resource use and costs.

Various follow-up models to prevent exacerbations and hospitalisations have been proposed. These include self-management, home care and dedicated chronic care models with or without support via information technologies.^5–7 The use of telehealth in COPD patients appears to have a possible effect on the quality of life of patients and the number of visits to the accident and emergency (A&E) department and hospital.⁸ However, little is known about the efficacy of telehealth in COPD patients with very advanced disease requiring long-term oxygen therapy (LTOT).

The main objective of the present study was to analyse the effectiveness of a telehealth programme in patients with advanced COPD treated with LTOT.

Methods

The study was designed as a randomized controlled trial. For the recruitment, the case manager contacted each of the candidates by telephone to confirm that they complied with the inclusion criteria; he also informed them about the study and its goals, and asked for their consent to participate in the study. Patients were recruited in stages and remained in the study for an average duration of four months. The inclusion criteria were: (1) being an adult patient with a diagnosis of COPD and chronic respiratory failure (CRF) with LTOT indication according to international guidelines;⁹ (2) at least one hospitalisation for respiratory illness in the previous year; (3) being clinically stable during the previous three months. The exclusion criteria were: patients who did not follow LTOT at enrolment, had no home telephone line or did not give their informed consent. The study was approved by the appropriate ethics committee.

Between September and December 2010 we identified 88 patients who met the inclusion criteria using the hospital's electronic records system. From this initial selection, 43 patients were excluded (Figure 1): 26 declined to participate, eight died, eight changed their LTOT indication during the recruitment phase and one patient was excluded for another reason.

Figure 1

Process of patient enrolment

Telehealth

Patients measured their vital signs from Monday to Friday according to a set schedule. Vital signs were acquired 20 min after taking prescribed inhaled therapy, seated and rested, and while on oxygen therapy. At the beginning of the study, nursing personnel installed the equipment in the patient's home and conducted a training session, showing each patient how to use the equipment and take measurements.

Vital signs were recorded using the following equipment: a spirometer, a pulse oximeter, a heart rate (Spirotel, Medical International Research Inc.) and a blood pressure monitor (model UA-767 BT, A&D Company). Each day, after taking these measurements, the data were sent via a hub (Tele-Modem, Aerotel Medical Systems) connected to the patient's home telephone line. Once measurements had been recorded by each connected instrument, the user pressed a button to activate data transmission.

Follow-up

Patients began participation in the study in a stable situation and the first measurements were taken at home under the supervision of the nursing staff. These measurements were used as reference values (baseline parameters) for each patient and alerts – to detect possible exacerbations – were activated by excursions outside the range of these reference values. The information was then received by the clinical call centre (CCC), manned by nurses, who used a triage application. This application provided the following indications:

(1)

Green alert: indicates that readings have been taken and are within predefined limits, and no further action is required.

(2)

Yellow alert: this is a non compliance or non adherence alert, and means that readings are either overdue or have not been received. In this case, the CCC personnel define the source and type of alert, and a response is given either by the CCC personnel or healthcare professionals according to a protocol.

(3)

Red alert: indicates that a reading falls outside the predefined limits. After verification of a red alert by the CCC staff, a clinical response procedure commences according to protocol.

Clinical response

The clinical response is the result of communication between the CCC staff, the case manager and a specialist in respiratory medicine. When a red alert is triggered, and before contacting the case manager, the CCC staff contact the patient to confirm the patient's symptoms, and gain more information about the severity of the exacerbation. If the clinical alert is confirmed, the CCC staff escalate the information to the case manager for an early response to a possible exacerbation. After receiving a red alert, the case manager analyses the vital sign measurements together with the clinical questionnaire responses, accessing the platform via mobile telephony (a smart phone) and initiating the clinical response.

The severity of the exacerbation dictates the subsequent actions:

(1)

Mild to moderate: in this case the case manager may choose to monitor vital signs for the following 24 hours, recommend treatment prescribed by the patient's doctor or refer to the primary care doctor.

(2)

Severe: referral to specialized care on the same day the alert is triggered.

(3)

Very severe: referral to an A&E department.

If the patient is admitted to hospital, the case manager will inform the CCC staff when the patient is discharged and the patient's monitoring process will resume.

Control group

Patients in the control group received conventional medical care. Health-related quality of life (HRQoL) questionnaires were administered at the beginning and at the end of the study during visits to patients’ homes by the nursing personnel. Information on the use of healthcare resources during the study was extracted from hospital information system databases.

Outcome measures

Evaluation of the telehealth programme was based on clinical outcome measures, self-perceived outcome measures by the patients and medical staff, and outcome measures from the healthcare system. The vital signs, rate of complications and rate of mortality were analysed. We evaluated the clinical and sociodemographic characteristics of patients at baseline, as well as the Charlson comorbidity index¹⁰ and baseline scores of HRQoL at the start of the study. We followed the recommendations of the American Thoracic Society (ATS)^11,12 and Spanish Society of Pulmonology and Thoracic Surgery (SEPAR)¹³ for spirometry standardization. SEPAR includes additional recommendations for arterial blood gas measurement.¹⁴

The St George Respiratory Questionnaire (SGRQ¹⁵ and EuroQol-5D questionnaire¹⁶ were administered at the beginning and end of the trial period. Note that a reduction in the score has the opposite meaning in these questionnaires: in SGRQ a lower score indicates an improvement in quality of life while in the EuroQol-5D it indicates a worsening.

Exacerbations

Exacerbation was defined as an acute change in the baseline clinical status of the patient beyond the daily variability, which presents with increased dyspnoea, expectoration, purulent sputum, or any combination of these three symptoms¹⁷ and requires a therapeutic change.

Effectiveness

The main outcome measures were exacerbations, A&E department visits and hospital admissions.

Satisfaction

Satisfaction of both patients and clinical professionals with the telehealth programme was assessed by administering a satisfaction questionnaire at the end of the study.

Results

A total of 45 patients were randomized: 21 to the control group and 24 to the telehealth group. Their sociodemographic characteristics, the Charlson comorbidity index and the baseline scores of HRQoL are summarised in Table 1.

Table 1

Baseline characteristics of patients

	Control group	Tele health group	P-value^*
No of men	20	23	0.92
No of women	1	1	0.92
Age, years (SD)	71 (10)	74(8)	0.18
FVC, % pred (SD)	63(17)	59(16)	0.69
FEV₁, % pred (SD)	37 (13)	38 (10)	0.33
RV, % pred (SD)	195 (34)	189 (38)	0.89
TLC, % pred (SD)	142 (15)	138 (15)	0.33
K_co, % pred (SD)	64 (19)	61 (21)	0.96
PaO₂, mmHg (SD)	53(5)	52(5)	0.77
PaCO₂, mmHg (SD)	47(4)	47(5)	0.86
Charlson index (SD)	2.5(1.5)	3.7 (2.7)	0.18
Adjusted Charlson index (SD)	5.1 (2.0)	6.6 (2.8)	0.07
SGRQ
Symptom scores (SD)	44 (23)	63 (23)	0.01
Activity scores (SD)	75 (24)	87 (20)	0.02
Impact scores (SD)	51 (25)	61 (20)	0.18
Total scores (SD)	57 (22)	69(17)	0.05
Severe problems
Mobility (%)	0(0)	3(14)	0.07
Self-care (%)	3(14)	7(33)	0.15
Usual activities (%)	6(28)	7(33)	0.74
Pain/discomfort (%)	2(10)	1 (5)	0.55
Anxiety/depression (%)	2(10)	2(10)	0.999
EuroQol-5D (SD)	0.55 (0.33)	0.44 (0.27)	0.24
VAS (SD)	55(13)	55(15)	0.89

FVC: forced vital capacity. FEV₁: volume expired in one second. RV: residual volume. TLC: total lung capacity. K_co % pred: carbon monoxide diffusion constant. PaO₂: arterial oxygen partial pressure. PaCO₂: arterial carbon dioxide partial pressure

Mann-Whitney U-test

Patients in the telehealth group took high rates of daily measurements of vital signs: blood pressure on 75% of days (average 90 days; SD 0.22), heart rate on 79% of days (average 96 days; SD 0.19), blood oxygen saturation on 71% of days (average 86 days; SD 0.22) and spirometry on 52% of days (average 63 days; SD 0.26). During the study, a total of 14 technical home visits and 408 telephone calls were made by the CCC: an average of 0.58 visits (SD 0.88) and 17 telephone calls (SD 7.75) per patient. The reasons for the telephone calls by the CCC were as follows: 38% for non-adherence (measurements had not been taken), 34% for non-receipt of data (technical or training problems), 19% clinical alerts (red alerts), 7% for technical reinforcement and 2% for other reasons.

During the study a total of 40 alerts were detected: 19 related to new exacerbation events and 21 following previous exacerbation events. Depending on their severity, the case manager either decided to continue monitoring and follow-up (32 cases) or refer patients to a specialized care consultation (8 cases). Two of these patients did not attend the appointment and ended up being hospitalized.

Two patients, one from each group, died during the study. This represents 5% of control patients and 4% of telehealth patients. The data relating to the use of healthcare resources and the differences in the HRQoL are summarised in Table 2.

Table 2

Use of healthcare resources and the differences in the HRQoL scores

	Control group	Telehealth group	P-value^*
A&E department visits
Percentage of patients visiting the A&E department at least once	33	17
Number of visits per patient (SD)	0.43 (0.68)	0.29 (0.75)	0.25
Specialized care consultations
Percentage of patients who were referred to specialized care unit	4.8	16.7
Number of visits per patient (SD)	0.05 (0.22)	0.25 (0.61)	0.20
Hospitalisations
Percentage of patients who were hospitalized at least once	14	21
Average number of hospitalisations per patient (SD)	0.14 (0.36)	0.38 (0.82)	0.47
Average hospital stay, days (SD)	1.4 (4.0)	4.4 (12.2)	0.50
SGRQ difference
Symptom score (SD)	–3.7 (19.6)	–12.8 (32.6)	0.31
Activity score (SD)	–4.0 (27.9)	–13.5 (25.4)	0.26
Impact score (SD)	–2.1 (23.2)	–8.7 (24.1)	0.38
Total score (SD)	–4.5 (19.7)	–10.9 (21.9)	0.53
EuroQol-5D difference (SD)	0.0034 (0.24)	0.0359 (0.28)	0.68

Mann-Whitney U-test

There were no significant improvements in the HRQoL of patients. However, patients were asked at the end of the study if their health had improved over the previous months. Of the control patients, 35% stated that their quality of life had improved, for 12% it had stayed the same, and for 53% it had worsened. In contrast, 46% of the telehealth patients said their quality of life had improved, 36% that it had stayed the same, and 18% that it had worsened (P = 0.05).

Satisfaction with the telehealth programme was evaluated by the four clinical professionals involved in the study (two nurses and two respiratory physicians), whose mean age was 44 years (SD 9) and average experience in clinical practice was 17 years (SD 13). The responses to the satisfaction questionnaires of the healthcare professionals and the patients are summarised in Tables 3 and 4, respectively.

Table 3

Satisfaction with the telehealth programme for the healthcare professionals participating in the study. Values shown are numbers of health professionals (%)

	Strongly disagree	Disagree	Agree	Strongly agree	P-value^*
Compared with conventional care, do you think that this programme has improved patient control and follow-up?	-	-	4 (100)	-	0.13
Compared to conventional care, do you believe this programme has reduced referrals to a lung specialist?	-	1 (25)	3 (75)	-	0.63
Compared to conventional care, do you believe this programme has reduced hospital admissions?	-	-	4 (100)	-	0.13
Do you think the equipment is easy to use for patients?	1 (25)	-	3 (75)	-	0.63
Do you believe that alerts generated by the programme are reliable?	-	3 (75)	1 (25)	-	0.63
Do you believe that the telehealth programme has improved patients’ quality of life?	-	1 (25)	3 (75)	-	0.63
Do you think that patients are more satisfied with the telehealth programme compared to conventional care on its own?	-	-	4(100)	-	0.13

Binomial test

Table 4

Patient satisfaction with the telehealth programme. Values shown are numbers of patients (%)

	Very dissatisfied	Dissatisfied	Satisfied	Very satisfied	No answer	P-value^*
How satisfied are you with the explanations about the operation and maintenance of equipment, given by staff who installed the equipment in your home?	2 (9)	-	7 (30)	14 (61)	-	0.009
How satisfied are you with the telephone support you received?	1 (4)	-	6 (26)	16 (70)	-	0.042
Are you satisfied with the troubleshooting of clinical and technical problems through the telephone support?	2 (9)	2 (9)	7 (30)	12 (52)	-	<0.001
How would you rate the safe operation of equipment?	2 (9)	5 (22)	10 (44)	5 (22)	1 (4)	0.008
	Strongly disagree	Disagree	Agree	Strongly agree	No answer
The telehealth programme has helped me cope better with my symptoms	1 (4)	6 (26)	6 (26)	9 (39)	1 (4)	0.030
The telehealth programme has helped me understand my illness better	3 (13)	5 (22)	10 (44)	4 (17)	1 (4)	0.030
The telehealth programme has helped me reduce my anxiety levels	1 (4)	3 (13)	5 (22)	13 (57)	1 (4)	0.043
The telehealth programme has allowed me to improve my autonomy and reduced my visits to the health centre or hospital	4 (17)	7 (30)	4 (17)	7 (30)	1 (4)	<0.001
The telehealth programme has had a positive impact on the way I live with my illness	1 (4)	2 (9)	13 (57)	7 (30)	-	0.24
I believe my family have benefited from the telehealth programme by reducing the potential psychological or physical burden related to my disease	2 (9)	1 (4)	11 (48)	6 (26)	3 (13)	0.001
	Very difficult	Difficult	Easy	Very easy	No answer
How would you rate the ease of use of equipment?	-	2 (9)	11 (48)	10 (44)	-	0.007

Chi-squared test

The same questionnaire asked healthcare professionals to rate their level of satisfaction with the telehealth programme (from 1 = very poor to 10 = very good). The mean score was 6.75 (SD 9.96).

Patients were asked to rate from 1 to 10 the following items: programme satisfaction, recommendation of the programme to a relative/friend may it be needed, and whether they would take part in another telehealth programme. The mean scores were 9.30 (SD 1.10), 9.39 (SD 1.95) and 9.61 (SD 0.89) respectively.

Discussion

The benefit of telehealth programmes in patients with COPD have been described in two systematic reviews.^8,18 However, the present study focused on patients with very advanced COPD and with indications of LTOT. This complicated the already challenging process of recruiting patients into a telehealth study¹⁹

Patients showed good compliance with the measurement of vital signs such as blood pressure, heart rate and oxygen saturation measurement, with measurements on 70–80% of days. However, patients performed spirometry measurements on only 52% of days. Hence during the study we decided to change from a daily measurement of spirometry to two measurements per week. The telehealth equipment showed good reliability, recording only 14 incidents related to equipment or failures of the remote connection. There was a large number of calls made by the CCC to patients, mostly due to their non-adherence to their daily measurements (38%) or non-receipt of data (34%). None of these incidents required technical assistance to be provided in the home.

Similar studies have shown a reduction in A&E department visits as well as in hospital admissions in the group of patients using telehealth.^20,21 In the present study, we observed a reduction in the number of A&E department visits but not in hospital admissions. The clinical triage process detected eight clinical exacerbations which were escalated by the case manager for a specialist respiratory consultation. Six of these patients attended the appointment, and were not admitted to hospital for the remainder of the study. Two other patients did not attend the appointment with the respiratory physician and were subsequently admitted to hospital. We also observed that a high percentage (75%) of patients admitted to hospital had previously visited the A&E department. We can therefore conclude that the detected exacerbations did reduce A&E visits and probably subsequent hospital admissions.

One aspect that should be considered in future studies is whether to continue the telehealth programmes during weekends and holidays. Had this been the case in the present study it would have avoided exacerbations occurring on those days which ended with patients being admitted to hospital (33% of the cases).

Another important aspect of the telehealth programme was the optimization of clinical resources, since the clinical response to the generated alerts did not involve a large number of health professionals. This was mainly due to the excellent communication and coordination established between the CCC, case manager and specialist in respiratory medicine involved in the study. The commitment of the professionals involved in such a programme is crucial for successful telehealth services.²²

There was no association between the telehealth programme and significant improvements in the HRQoL of patients. There were clinically important differences in both groups, as shown by the improvement of at least 4 units in the SGRQ total score,²³ although patients in the telehealth group improved in all dimensions of the SGRQ, while patients in the control group did so only in the total score. The difference between the groups was 9.1 (SE 8.1) in the Symptoms dimension, 9.5 (SE 8.2) in the Activity dimension, 6.7 (SE 7.2) in the Impact dimension and 6.4 (SE 6.3) in Total dimension. Regarding the EuroQol-5D, patients in the telehealth group obtained an increase in the mean score of 0.03 (SE 0.08) compared to patients in the control group. However, 47% of patients in the control group and 82% of patients in the telehealth group felt that their health status had improved or stayed the same over the months of the study.

Patients showed a high level of satisfaction with the telehealth programme in line with a previous similar study²⁴ The question with the poorest response rate was about patients’ perception of the programme increasing their autonomy and reducing their visits to the primary care centre or hospital. However, there were high mean scores, above 9 on a scale of 1 to 10, in questions related to the degree of the satisfaction with the programme, with the recommendation of the programme to a relative/friend and the willingness to participate in another telehealth programme. Clinical professionals rated all items positively except for the satisfaction concerning the reliability of the alerts generated by the system. This was due to the high number of false positives, i.e. the alerts generated by non-medical problems, mainly because of patients’ failure to adhere to daily measurements. In previous telehealth studies the general approach to triage has been for both technical and clinical triage to be done by the CCC. Other telehealth projects have sought to embed the clinical triage process in the day to day duties of the clinician responsible, often the community nurse responsible for the case load. The most efficient programmes are those including both technical and clinical triage processes by the call centre, in our case the CCC, since this is the main route for filtering false positives.

There were two important limitations in the present study: the small sample size and the short study duration.

Conclusions

The telehealth programme for patients with very severe COPD and in need of LTOT was found to be technically feasible. The holistic model consisting of a combination of telemonitoring, the CCC, case manager and a specialist in respiratory medicine was effective in detecting exacerbations and issuing a prompt clinical response. No marked improvement in the HRQoL and healthcare resource utilization was observed, but there was a significant reduction in A&E department visits, which for this fragile group of patients is usually the threshold for hospital admission. Overall there was a high level of satisfaction for both patients and healthcare professionals with the telehealth programme.

Footnotes

Acknowledgements

The study was financed by the Spanish Ministry of Science and Innovation. We thank Linde Healthcare for participating in the study and financing the medical equipment. We thank the Network for Innovation in Medical Technologies and Health (Red ITEMAS in Spanish), grant number RD09/0077/00025, promoted by the Carlos III Health Institute.

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