Abstract
Rationale. To evaluate the feasibility of a second-opinion consultation in supporting general practitioners (GPs) during the daily diagnosis and therapeutic management of patients with essential hypertension. Methods. Italian GPs were encouraged to follow-up their patients by the use of the Telemedicine Service. All known hypertensive patients with signs and symptoms (teleconsultation for symptoms) and all asymptomatic patients (teleconsultation for clinical control) undergoing a visit by their GPs were enrolled. During the first visit, the GP performed electrocardiography (ECG), measured blood pressure and required cardiological teleconsultation. Results. 399 GPs examined 1719 consecutive patients (mean age 73±13 years, 38% male). During teleconsultation for a routine control, GPs identified 36% of new episodes of atrial fibrillation in the absence of any symptom and about 70% of patients with uncontrolled blood pressure. In about 50% of the cases, 10 min of teleconsultation helped GP to quicken the solution of the clinical problems, reducing time and number of specialist's visit. In 8% of cases, an emergency department admission was suggested. Conclusions. Telemedicine applied to hypertensive patients at high risk of cardiovascular problems offers to GPs an easy-to-use tool to control blood pressure by improving connection with second-opinion specialist consultations.
Introduction
Essential hypertension (EH) is one of the main risk factors for the development of cardiovascular (CV) and cerebrovascular diseases, and is an important determinant of mortality and morbidity in developed countries (Citation1).
Until now, only one-fourth of patients with hypertension have their blood pressure (BP) controlled according to the guidelines recommendations (Citation2,Citation3) and there is evidence that this figure is decreasing (Citation3). Moreover, most of the hypertensive population tends to underestimate the importance of BP control when only a mild increase in systolic BP (SBP) is present. However, it has been shown that about two-thirds of the events occur when SBP is in the range of ≥160 mmHg and, as a consequence, the incidence of stroke, coronary disease, end-stage renal failure and congestive heart failure (CHF) is progressively increasing (Citation4). Among all the causes of inadequate BP control, lack of interaction between general practitioners (GPs) and specialists (Citation5) may result in too long waiting lists for specialists’ consultations; moreover, patients’ compliance to therapy still represents a critical point often underestimated (Citation6). In order to reach the gold standard in hypertension treatment, a shift in care delivery is needed, based on new collaborative approaches between GPs and clinical specialists, as suggested by the European Society of Hypertension (ESH) guidelines (Citation4,Citation7).
Telemedicine (TM) could represent a new strategy in the management of the disease, allowing connection of GPs with the expertise of specialists through a telematic system based on the use of telephone, specific software and the support of devices recording biological signals (Citation8,Citation9).
So far, in Italy several different scenarios may be observed: in the urban area, patients go directly to the specialists to solve their medical problems, while in the suburban areas many patients prefer to contact their GPs because of a closer relationship with them, an underestimation of symptoms or the distance of the specialist center from home (Citation10). As previously reported in the literature, a telecardiology second opinion may be particularly useful in solving GPs’ problems (Citation11), thus providing a solid diagnostic value to support GPs’ activity (Citation10,Citation12–14).
According to 2007 ESH/ESC, JNC-7 and BHS guidelines (Citation7,Citation15,Citation16), ECG is the first non-invasive tool for identifying and following up over time high-risk patients. In order to avoid referral of patients to the hospital only for an ECG (very inconvenient, especially in elderly patients or in those patients needing a caregiver), GPs can be encouraged to follow up their patients by the use of a TM Service (TMS); ECG reporting and interactive teleconsultation, during the daily activity in the office or at patient's home, may help GPs to ascertain the most appropriate treatment for the patient's disease.
The aim of the current study was to evaluate the feasibility of ECG interpretation and interactive consultation in hypertensive patients attending a visit to their GPs at the time of the first teleconsultation into the TM Program in order: (i) to evaluate whether cardiological teleconsultation (second opinion) between GPs and clinical specialists could be useful in providing support to the diagnosis and therapeutic daily management of hypertensive patients; (ii) to assess the degree of BP control in asymptomatic patients with EH; and (iii) to characterize clinical differences between younger and older hypertensive patients.
Methods
General practitioners
Between May 2002 and November 2008, GPs from all Italian regions were asked to participate in a cardiological teleconsultation program through a TMS [Health Telematic Network (HTN)].
GPs were equipped with a portable, personal 12 lead-ECG (Card-Guard 7100, Rehovot, Israel), which could record and transfer, by either a mobile or a fixed telephone, an ECG tracing to the TMS, where a specialist was available for the cardiological second opinion. ECG tracing could be recorded everywhere, in any setting, either in emergency or in elective conditions.
In addition, during this call, GPs also reported to the specialist the patient's BP values measured in the office and, in cases of need, asked advice on both diagnostic and therapeutic assessments. GPs were responsible for their patients in terms of clinical evaluation, education and communication of the data to TMS; in brief, during daily in-office or home visits, GP performed a 12-lead ECG through a device with a signaling telephonic transmission, measuring SBD and diastolic BP (DBP) following European Guidelines (Citation4,Citation7) and called the TMS asking for a teleconsultation. By phone, GP provided to the TMS the general patient's demographic information together with medical history, clinical risk factors, physical signs, therapy and current symptoms (if present), then transmitted the ECG tracing.
All data were reported in the patient's personal health record (PHR). GPs were then in contact with the specialists who could address questions, report comments on the ECG tracing and discuss the diagnostic procedures to undertake [e.g. no action, need to refer the patient to an emergency department (ED), request for further investigations]. In case of BP value ≥140/90 mmHg, the specialist and GP could discuss the need for a new drug or changes in the therapeutic scheme. At the end of the teleconsultation, the TMS recorded all information received from the GP, the suggested interventions, and faxed or e-mailed the ECG reports to GPs.
Specialists were available 24 h/day, 365 days/year in a teleworking model, offering in real time ECG reporting and an interactive teleconsultation with the GPs. TM consultation, defined as a “specialist” second opinion, was performed by cardiologists and/or internists. All medical doctors participating in this program had undergone a preliminary educational course aimed at improving the use of patient's PHR on the TM platform and their communication skills. In addition, GPs were asked to show an adequate knowledge of and adherence to the most recent guidelines, as suggested by the National and ESH/ESC Guidelines (Citation7).
Blood pressure measurements
SBP and DBP were measured at the GP's office in a sitting position with flexed arm, repeating three different evaluations within 5 min by the use of a traditional mercury sphygmomanometer (diastolic BP phase V Korotkov). Patients with blood pressure >140/90 mmHg were defined as hypertensive according to the ESH guidelines.
Patients
All hypertensive patients with signs and symptoms suggestive of a new acute event or of worsening of a previous disease (teleconsultation for symptoms), and all asymptomatic patients with EH who needed an ECG for diagnostic procedure during a “routine” control visit (teleconsultation for control) by GPs, were enrolled into the study. Each patient was asked to sign an informed consent in order to create a PHR to be included in the database of the TMS.
The Technical Scientific Committee of Fondazione Salvatore Maugeri approved the protocol and the study has been conducted in accordance with the Declaration of Helsinki.
Telemedicine Service and data collection
TMS, as previously described (Citation8), was equipped with four servers (Hewlett Packard, ID, USA): a SQL database, a terminal server connected through a Virtual Private Network (VPN), a web server for Internet connection and a domain controller. A computerized call centre, LAN workstations with printers and a central fax machine with back-up hardware to avoid activity interruptions and firewall for data security were also provided.
All the consultations’ data – collected by the TMS following its own policies – were recorded and the images were stored in the PHR within the TMS clinical database. TMS also collected all follow-up information and data relative to patients sent to the ED after the TMS consultation, obtained by asking GPs about the discharge diagnosis by the ED. For those patients who stayed at home, GPs were also asked to report any event (as ED or hospital admission) possibly occurring within 48 h after the TMS consultation.
Statistical analysis
All data were descriptively analyzed. Two-sided unpaired Student's t-test was applied for comparison of the mean values. Z-test was used for comparison of proportions between subgroups. p-values <0.05 were considered statistically significant.
Results
During the study period, 399 GPs were randomly selected all over Italy: 54% in the northern, 29% in the central, and 17% in the southern regions and islands. A teleconsultation was asked in a mean number of 4.3 patients with a diagnosis of hypertension/GP.
All data describe the patient's population identified by GPs at time of the first teleconsultation with the TMS. Data were referred by GPs themselves to the TMS.
General characteristics
shows the anthropometric characteristics of the 1719 patients, collected during the first teleconsultation required by the GP. The mean age of the whole population was 73±13 years (62% female and 38% male); 1054 (61.3%) of 1719 patients have EH, and 327 had hypertensive (14%) or ischemic (5.1%) heart disease. Valvular diseases or previous episodes of atrial fibrillation (AF) were reported in 12 (0.7%) and 67 (3.9%) cases, respectively. Diabetes mellitus was present in 13.3% of patients.
Table I. General characteristics of patients' population at first consultation by general practitioners.
The whole population (n = 1719) was divided into two subgroups according to the age median value (75 years): 899 (52.3%) patients were ≤75 years (Group 1) and 820 (47.4%) were >75 years (Group 2), respectively. Elderly patients in Group 2 (mean age 84 ± 5 years), were mainly female (72%) with a significantly higher heart rate (HR) (p < 0.01), a greater percentage of previous pacemaker implantation (p < 0.001) and of AF (16% vs 4%). The prevalence of hypertensive heart disease as well as valvular heart diseases was higher in this older age group of patients.
Clinical data according to different type of teleconsultation
reports the reasons for the second-opinion request: teleconsultation for routine visit in 52.5% of patients and teleconsultation for occurrence of symptoms in 47.5%. Patients’ symptoms were chest pain (41.6%), palpitations (17.4%), dyspnea (15.2%); hypertensive “crisis” (9.2%), weakness (8.7%), pre-syncope/syncope (4.6%), ankle edema (0.3%) and other minor reasons (2.9%).
Table II. Clinical data for both routine and symptoms teleconsultation.
During teleconsultation for routine control (, first column), ECG could confirm the presence of AF in absence of any symptoms in 60 patients (7%), especially in the oldest group of patients.
When the reason for a teleconsultation was the occurrence of symptoms, patients had higher HR (p < 0.05) and in 13.1% of them a new episode of AF was diagnosed (, first column).
BP values in the PHR () were referred in 651 out of 817 of patients (79.7%) coming for symptoms and in 666 out of 902 patients (73.8%) coming for a routine visit, in a significantly greater percentage in Group 1 (, p < 0.001). During the routine telecontrol visit in asymptomatic patients, BP data were recorded by GPs in a slightly lower percentage of patients compared with those referred for symptoms. Mean values of SBP and DBP in the whole population were 147.4 ± 22.5 and 85.7 ± 11.3 mmHg, respectively.
Table III. Blood pressure (BP) values monitored at first teleconsultation by general practitioners.
According to the definition of the European Guidelines, BP control during routine teleconsultation in asymptomatic patients () was reached in 28.2% of patients (ranging from 24.5% to 34.4% in Groups 1 and 2, respectively). The remaining portion of 71.8% patients had uncontrolled BP (): as expected, isolated systolic hypertension was mainly present in the elderly (41.5%).
Table IV. Blood pressure (BP) values of asymptomatic patients monitored at first consultation by general practitioners.
Therapy in the patients’ population
As far as the antihypertensive treatment is concerned, angiotensin-converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARBs) were the most frequently used classes of drugs (51%) followed by Ca-antagonists and diuretics (38% for both), and beta-blockers (18%). Statins were used in a small portion of patients (6%). Antiplatelets and anticoagulants were used in 20% and 3% of patients, respectively.
Patients receiving previous antihypertensive treatment at time of consultation were treated with one CV drug in 38.6%, with two CV drugs in 34.4%, with at least three CV drugs in 12.6% and with more than three in 32.7% of patients; 1.7% of patients received no CV drug.
Clinical suggestions during teleconsultation by the specialist
Telecardiology consultations were mainly performed while the patient was in the GP's office (87.3%), and 12.7% of them were performed at patients’ home. Consultations required an average time of 8.83 ± 6.47 min/patient (without difference between office and home).
When teleconsultations between specialist and GPs during a control visit were compared with those for symptoms, a significant difference in terms of management was observed.
During teleconsultation for symptoms (), therapeutic intervention (33.3% vs 23.4%) and the need for a new examination (19.6% vs 8.6%) were significantly higher in patients referred for symptoms (p < 0.05 for both), and the suggestion for ED admission increased from 0.4% to 16% with respect to teleconsultation for a control visit.
Table V. Clinical suggestions of specialist to general practitioner through Telemedicine Service.
During teleconsultation for a control visit, no further actions (i.e. no changes in treatment and/or in drugs) were chosen in 66.4% of the cases. However, teleconsultations suggested changes in therapy in 23.4% and new examinations in 8.6% of the cases.
In few cases (mainly identification of asymptomatic AF), further evaluation was suggested.
Discussion
We report the results of a pilot study in a population of EH patients followed up by a group of GPs adhering to a TMS by the use of a second-opinion consultation.
We considered all patients attending the GP's office with “essential arterial hypertension”. We believe that our study population is rather homogeneous: all have hypertension with or without cardiomyopathy (5.1% and 14.0% for ischemic and hypertensive CM), with low-rate comorbidities (13% with diabetes).
In particular, the current study shows that GPs – by the use of TM – can improve the evaluation and management of hypertensive patients in real time by identifying an acute clinical event by suggestive symptoms and signs or by confirming the presence of supraventricular tachyarrhythmias. Therefore, the TMS allows a faster symptom evaluation.
In addition, TMS may give specialist's suggestions to GPs, possibly reassuring them when changes in treatment strategies are needed, reducing the time gap usually occurring between the occurrence of symptoms and the specialist diagnosis.
In previous studies (Citation17,Citation18), we already showed that GPs, by teleconsultation, avoided up to 95% of cardiological visits and reduced to 47% the ER referral, thus limiting workload and costs on the healthcare system. The aim of the current study was to provide the GP a service that could avoid wasting time and useless visits, allowing monitoring of hypertensive patients by teleconsultation.
As far as the prevalence of risk factors and the BP control are concerned, hypertensive patients included in our study are similar to that reported by Volpe et al. (Citation19), who examined data on 52,715 patients evaluated in epidemiological studies and in specialist centers in Italy.
In the current study, in accordance with our previous experiences (Citation17,Citation18), the cardiological second opinion has generally quickened and helped GPs in presenting a possible solution to the problems in about 50% of cases. In particular, during the visits for symptoms, the second opinion significantly speeded up changes in therapy, requests for new examinations or suggestions for ED admissions.
GPs are aware of the need for BP values to be maintained according to current guidelines, but these are often difficult to reach in the daily practice. Teleconsultation helps with managing this issue: second opinion was useful to identify about 70% of asymptomatic patients with uncontrolled BP, thus allowing for selection of proper treatment.
The results of the current study confirm that less than 30% of the EH is controlled at the time of the first TMS consultation (Citation3). BP normalization is not frequently achieved in clinical trial setting (Citation20), and in daily practice, an even worse BP may be observed: the reasons for such a poor result in BP control in treated patients include both patient-related factors (non-compliance to treatment, difficulties in assessing health care and others) and physician-related factor (clinical inertia to evaluate/change therapy, number of BP measurements during clinical visits, lack of interaction with specialists and others) (Citation15,Citation21).
This result is in accordance with Filippi et al. (Citation21), who, in a recent Italian survey on 800,000 patients by 550 GPs, showed that, when recorded, uncontrolled BP was found in 43% of patients. Similarly, BP values were measured and recorded in a portion of patients, and not in all.
Moreover, the majority of patients – referred by GPs to the specialist – were checked in about 10 min, thus avoiding long waiting list for specialist visits. The efficacy of the use of teleconsultation for GPs has been previously reported in other specialties with similar results (Citation22–24). Second opinion was useful in reducing the need for a “standard” specialist visit for an ECG examination: this result has been already obtained and reported also for other specialties such as dermatology (Citation25,Citation26).
When GPs referred to the TMS for patients with acute symptoms, suggesting a high-risk condition for an acute CV event, ED admission was suggested to patients. In a large percentage, AF was diagnosed and patients were hospitalized, confirming the evidence that arterial hypertension is a major risk factor for supraventricular arrhythmia and AF; only in one case was ED admission required in a patient with a hypertensive urgency.
Another possible application of TMS could be the patients’ follow-up during treatment. De Luca et al. (Citation5) observed that when GPs were involved in TM programs, their patients were followed up more accurately: consultations more frequently resulted in both better patients’ compliance and treatment adherence.
In our group of patients, we could observe significant differences only in the occurrence of AF, and not in hypertensive complications and/or comorbidities.
Elderly patients – despite several comorbidities – are often treated only by their GP without any specialist consultation. This is because of the difficulty for this population to reach specialists, often needing the assistance of a caregiver. TM can offer GPs a cardiological second opinion, which favors the accuracy of the diagnostic pathway and management of patients themselves (Citation10).
TM applied to the management of patients at high CV risk could significantly cut down the costs of the National Health System (NHS) by reducing the time to access to specialist visits in the NHS (Citation11), ED admissions and specialist visits and possibly improving BP in patients under treatment for hypertension. Since about 50% of our population was older than 75 years, we propose that the TMS could also avoid indirect costs linked to the time spent by the caregiver to bring the patient to the specialist, as already observed by our TMS (Citation17).
Limitations of the study
This is an observational pilot study on the use of TM by GPs in the care of hypertensive patients. We have observed that the data provided by the GPs were complete only in the 77% of patients, thus suggesting a need for a more accurate data recording by GPs themselves and specialists.
Despite this incompleteness, the amount of analyzed data could be sufficient to give a picture of the situation of GPs in Italy, a country where filling in a PHR is not a routine activity for GPs.
Although this is not our first experience with teleconsultation for GPs and we have performed training meetings to GPs on the importance and outcome of the call after the visits, GPs were free to decide whether to call the patients: in other words, we cannot oblige GPs to call for each control. This is still an explorative study on a methodology, which warrants further investigation and is thus not yet part of the daily practice of any GP.
Last, our study could not be designed as a cost- and time-saving trial for the NHS.
Conclusions and future directions
TM applied to cardiology offers to both GPs and patients an easy-to-use tool for controlling BP, by improving connection with second-opinion specialist consultations.
TM has a variety of applications in the clinical setting. Large-scale clinical trials at both national and international levels are needed to define its potentialities from a scientific point of view and in the frame of organization and political aspects.
Being a new function of the technology, it first needs to be accurately studied, then widely spread over the territory, with the objective of reaching the most frail patients, who can be elderly, supporting their GP in diagnosis and decision making. One of our aims for future studies is the evaluation of the follow-up of such patients, to verify whether the corrected measures applied in these patients through this service can be maintained over time.
Moreover, the potential of both cost- and time-saving for healthcare organizations is another imperative of the future clinical research in this field.
Acknowledgments
We thank all the specialists (both cardiologists and internists) who participated to the project from: Fondazione Salvatore Maugeri, IRCCS Lumezzane (Brescia): Angelo Cinelli, Emanuela Zanelli; ASL Brescia: Antonio Tirinato; Fondazione Poliambulanza – Brescia: Antonio Maggi; AO Desenzano del Garda (Brescia): Massimo Benigno, Carlo Ferretti, Carlo Zappa; Ospedale di Chiari (Brescia): Francesco Dalla Valle, Diego Domenighini, Domenica Raccagni; San Camillo Forlanini – Roma: Marco Pugliese; Ospedali Riuniti – Bergamo: Nicola Cuocina; Ospedale Maggiore di Crema: Pietrocarlo Gazzaniga, Angelo Lodi Rizzini; ASL di Genova: Giorgio Tommasini. We also thank dr. Alessandro Bettini for the English revision of the manuscript.
Source of funding
The Call Center's equipment (PC) and cost of calls were mainly sustained by the Health Telematic Network (HTN) and covered by an agreement between HTN and GPs. Each author performed the work inside his/her usual daily work activity. They were paid by his/her monthly salary by their own relative institutions.
Conflicts of interest to disclosure: The authors declare no conflict of interest.
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