Examining the effectiveness of telemonitoring with routinely acquired blood pressure data in primary care: challenges in the statistical analysis.

BACKGROUND: Scale-up BP was a quasi-experimental implementation study, following a successful randomised controlled trial of the roll-out of telemonitoring in primary care across Lothian, Scotland. Our primary objective was to assess the effect of telemonitoring on blood pressure (BP) control using routinely collected data. Telemonitored systolic and diastolic BP were compared with surgery BP measurements from patients not using telemonitoring (comparator patients). The statistical analysis and interpretation of findings was challenging due to the broad range of biases potentially influencing the results, including differences in the frequency of readings, 'white coat effect', end digit preference, and missing data. METHODS: Four different statistical methods were employed in order to minimise the impact of these biases on the comparison between telemonitoring and comparator groups. These methods were "standardisation with stratification", "standardisation with matching", "regression adjustment for propensity score" and "random coefficient modelling". The first three methods standardised the groups so that all participants provided exactly two measurements at baseline and 6-12 months follow-up prior to analysis. The fourth analysis used linear mixed modelling based on all available data. RESULTS: The standardisation with stratification analysis showed a significantly lower systolic BP in telemonitoring patients at 6-12 months follow-up (-4.06, 95% CI -6.30 to -1.82, p < 0.001) for patients with systolic BP below 135 at baseline. For the standardisation with matching and regression adjustment for propensity score analyses, systolic BP was significantly lower overall (- 5.96, 95% CI -8.36 to - 3.55 , p < 0.001) and (- 3.73, 95% CI- 5.34 to - 2.13, p < 0.001) respectively, even after assuming that - 5 of the difference was due to 'white coat effect'. For the random coefficient modelling, the improvement in systolic BP was estimated to be -3.37 (95% CI -5.41 to -1.33 , p < 0.001) after 1 year. CONCLUSIONS: The four analyses provide additional evidence for the effectiveness of telemonitoring in controlling BP in routine primary care. The random coefficient analysis is particularly recommended due to its ability to utilise all available data. However, adjusting for the complex array of biases was difficult. Researchers should appreciate the potential for bias in implementation studies and seek to acquire a detailed understanding of the study context in order to design appropriate analytical approaches.

Telemonitoring at scale for hypertension in primary care: An implementation study.

BACKGROUND: While evidence from randomised controlled trials shows that telemonitoring for hypertension is associated with improved blood pressure (BP) control, healthcare systems have been slow to implement it, partly because of inadequate integration with existing clinical practices and electronic records. Neither is it clear if trial findings will be replicated in routine clinical practice at scale. We aimed to explore the feasibility and impact of implementing an integrated telemonitoring system for hypertension into routine primary care. METHODS AND FINDINGS: This was a quasi-experimental implementation study with embedded qualitative process evaluation set in primary care in Lothian, Scotland. We described the overall uptake of telemonitoring and uptake in a subgroup of representative practices, used routinely acquired data for a records-based controlled before-and-after study, and collected qualitative data from staff and patient interviews and practice observation. The main outcome measures were intervention uptake, change in BP, change in clinician appointment use, and participants' views on features that facilitated or impeded uptake of the intervention. Seventy-five primary care practices enrolled 3,200 patients with established hypertension. In an evaluation subgroup of 8 practices (905 patients of whom 427 [47%] were female and with median age of 64 years [IQR 56-70, range 22-89] and median Scottish Index of Multiple Deprivation 2012 decile of 8 [IQR 6-10]), mean systolic BP fell by 6.55 mm Hg (SD 15.17), and mean diastolic BP by 4.23 mm Hg (SD 8.68). Compared with the previous year, participating patients made 19% fewer face-to-face appointments, compared with 11% fewer in patients with hypertension who were not telemonitoring. Total consultation time for participants fell by 15.4 minutes (SD 68.4), compared with 5.5 minutes (SD 84.4) in non-telemonitored patients. The convenience of remote collection of BP readings and integration of these readings into routine clinical care was crucial to the success of the implementation. Limitations include the fact that practices and patient participants were self-selected, and younger and more affluent than non-participating patients, and the possibility that regression to the mean may have contributed to the reduction in BP. Routinely acquired data are limited in terms of completeness and accuracy. CONCLUSIONS: Telemonitoring for hypertension can be implemented into routine primary care at scale with little impact on clinician workload and results in reductions in BP similar to those in large UK trials. Integrating the telemonitoring readings into routine data handling was crucial to the success of this initiative.

Supported Telemonitoring and Glycemic Control in People with Type 2 Diabetes: The Telescot Diabetes Pragmatic Multicenter Randomized Controlled Trial.

BACKGROUND: Self-monitoring of blood glucose among people with type 2 diabetes not treated with insulin does not appear to be effective in improving glycemic control. We investigated whether health professional review of telemetrically transmitted self-monitored glucose results in improved glycemic control in people with poorly controlled type 2 diabetes. METHODS AND FINDINGS: We performed a randomized, parallel, investigator-blind controlled trial with centralized randomization in family practices in four regions of the United Kingdom among 321 people with type 2 diabetes and glycated hemoglobin (HbA1c) >58 mmol/mol. The supported telemonitoring intervention involved self-measurement and transmission to a secure website of twice-weekly morning and evening glucose for review by family practice clinicians who were not blinded to allocation group. The control group received usual care, with at least annual review and more frequent reviews for people with poor glycemic or blood pressure control. HbA1c assessed at 9 mo was the primary outcome. Intention-to-treat analyses were performed. 160 people were randomized to the intervention group and 161 to the usual care group between June 6, 2011, and July 19, 2013. HbA1c data at follow-up were available for 146 people in the intervention group and 139 people in the control group. The mean (SD) HbA1c at follow-up was 63.0 (15.5) mmol/mol in the intervention group and 67.8 (14.7) mmol/mol in the usual care group. For primary analysis, adjusted mean HbA1c was 5.60 mmol/mol / 0.51% lower (95% CI 2.38 to 8.81 mmol/mol/ 95% CI 0.22% to 0.81%, p = 0·0007). For secondary analyses, adjusted mean ambulatory systolic blood pressure was 3.06 mmHg lower (95% CI 0.56-5.56 mmHg, p = 0.017) and mean ambulatory diastolic blood pressure was 2.17 mmHg lower (95% CI 0.62-3.72, p = 0.006) among people in the intervention group when compared with usual care after adjustment for baseline differences and minimization strata. No significant differences were identified between groups in weight, treatment pattern, adherence to medication, or quality of life in secondary analyses. There were few adverse events and these were equally distributed between the intervention and control groups. In secondary analysis, there was a greater number of telephone calls between practice nurses and patients in the intervention compared with control group (rate ratio 7.50 (95% CI 4.45-12.65, p < 0.0001) but no other significant differences between groups in use of health services were identified between groups. Key limitations include potential lack of representativeness of trial participants, inability to blind participants and health professionals, and uncertainty about the mechanism, the duration of the effect, and the optimal length of the intervention. CONCLUSIONS: Supported telemonitoring resulted in clinically important improvements in control of glycaemia in patients with type 2 diabetes in family practice. Current Controlled Trials, registration number ISRCTN71674628. TRIAL REGISTRATION: Current Controlled Trials ISRCTN 71674628.

Correction: Supported Telemonitoring and Glycemic Control in People with Type 2 Diabetes: The Telescot Diabetes Pragmatic Multicenter Randomized Controlled Trial.

[This corrects the article DOI: 10.1371/journal.pmed.1002098.].

Home blood pressure monitoring: methodology, clinical relevance and practical application: a 2021 position paper by the Working Group on Blood Pressure Monitoring and Cardiovascular Variability of the European Society of Hypertension.

The present paper provides an update of previous recommendations on Home Blood Pressure Monitoring from the European Society of Hypertension (ESH) Working Group on Blood Pressure Monitoring and Cardiovascular Variability sequentially published in years 2000, 2008 and 2010. This update has taken into account new evidence in this field, including a recent statement by the American Heart association, as well as technological developments, which have occurred over the past 20 years. The present document has been developed by the same ESH Working Group with inputs from an international team of experts, and has been endorsed by the ESH.

The case for home monitoring in hypertension.

Although the assessment of cardiovascular risk in individual patients takes into account a range of risk factors, the diagnosis and management of hypertension (high blood pressure) is largely determined by a single numerical value, albeit that often several readings are taken over time. Given the critical impact of a decision to embark on lifelong drug therapy, the importance of ensuring that a blood pressure (BP) record is both accurate and representative is clear. However, there is good evidence that the variability of BP is such that even if measurement is of the highest quality, it can be difficult to say with confidence whether a patient is above or below a treatment threshold. This commentary argues that current BP measurement is inadequate to make the clinical decisions that are necessary and that multiple readings are required to deliver an acceptable degree of accuracy for safe decision-making. This is impractical in a doctor's surgery, and the only realistic long-term strategy is to involve the patient in measuring his or her own BP in their own environment. Evidence is presented that such a strategy is better able to predict risk, is cost-effective for diagnosing hypertension, can improve BP control and is thus better able to protect individuals in the future. In this commentary, I explain why doctors and other healthcare professionals should increase their familiarity with the technology, be aware of its strengths and limitations and work with patients as they become more empowered in the management of their chronic condition, hypertension.

Phosphodiesterase type 5 inhibition reverses impaired forearm exercise-induced vasodilatation in hypertensive patients.

OBJECTIVE: Established hypertension is characterized by increased peripheral vascular resistance and endothelial dysfunction, features that may underlie the reduced exercise-induced vasodilatation seen in hypertensive patients. Sildenafil citrate is a phosphodiesterase type 5 (PDE5) inhibitor used clinically for the treatment of male erectile dysfunction. Its vasodilating properties are due to the inhibition of cyclic guanosine monophosphate (cGMP) breakdown and prolongation of the signalling actions of the nitric oxide (NO)-cGMP pathway in vascular smooth muscle cells. Sildenafil has beneficial effects on endothelial function and exercise tolerance in congestive heart failure and pulmonary hypertension, and we hypothesized that it would improve exercise-induced vasodilatation in hypertensive patients. METHODS AND RESULTS: Ten hypertensive patients and ten matched normotensive subjects were studied in a three-way, randomized, single-blind and placebo-controlled study. On each study day, forearm blood flow (FBF) responses to handgrip exercise were assessed before and after intra-arterial (brachial) infusion of sildenafil, verapamil (a control, cGMP-independent vasodilator), and saline (placebo). Preinfusion exercise-induced vasodilatation was significantly reduced in hypertensive patients compared to normotensive controls. Sildenafil and verapamil infusions both caused a similar increase in baseline FBF. However, while verapamil did not affect the vasodilator response to handgrip exercise in either group, sildenafil substantially enhanced this response in hypertensive patients, but not in normotensive subjects. CONCLUSIONS: Our data suggest that sildenafil, through an increase in cGMP levels in the vasculature, substantially and selectively improves the vasodilator response to handgrip exercise in hypertensive patients. These findings represent an essential first step in support of further studies exploring the potentially beneficial effects of PDE5 inhibition on impaired exercise capacity in hypertension.

European Society of Hypertension guidelines for blood pressure monitoring at home: a summary report of the Second International Consensus Conference on Home Blood Pressure Monitoring.

This document summarizes the available evidence and provides recommendations on the use of home blood pressure monitoring in clinical practice and in research. It updates the previous recommendations on the same topic issued in year 2000. The main topics addressed include the methodology of home blood pressure monitoring, its diagnostic and therapeutic thresholds, its clinical applications in hypertension, with specific reference to special populations, and its applications in research. The final section deals with the problems related to the implementation of these recommendations in clinical practice.

Are self-reported telemonitored blood pressure readings affected by end-digit preference: a prospective cohort study in Scotland.

OBJECTIVE: Simple forms of blood pressure (BP) telemonitoring require patients to text readings to central servers creating an opportunity for both entry error and manipulation. We wished to determine if there was an apparent preference for particular end digits and entries which were just below target BPs which might suggest evidence of data manipulation. DESIGN: Prospective cohort study SETTING: 37 socioeconomically diverse primary care practices from South East Scotland. PARTICIPANTS: Patients were recruited with hypertension to a telemonitoring service in which patients submitted home BP readings by manually transcribing the measurements into text messages for transmission ('patient-texted system'). These readings were compared with those from primary care patients with uncontrolled hypertension using a system in which readings were automatically transmitted, eliminating the possibility of manipulation of values ('automatic-transmission system'). METHODS: A generalised estimating equations method was used to compare BP readings between the patient-texted and automatic-transmission systems, while taking into account clustering of readings within patients. RESULTS: A total of 44 150 BP readings were analysed on 1068 patients using the patient-texted system compared with 20 705 readings on 199 patients using the automatic-transmission system. Compared with the automatic-transmission data, the patient-texted data showed a significantly higher proportion of occurrences of both systolic and diastolic BP having a zero end digit (OR 2.1, 95% CI 1.7 to 2.6) although incidence was <2% of readings. Similarly, there was a preference for systolic 134 and diastolic 84 (the threshold for alerts was 135/85) (134 systolic BP OR 1.5, 95% CI 1.3 to 1.8; 84 diastolic BP OR 1.5, 95% CI 1.3 to 1.9). CONCLUSION: End-digit preference for zero numbers and specific-value preference for readings just below the alert threshold exist among patients in self-reporting their BP using telemonitoring. However, the proportion of readings affected is small and unlikely to be clinically important. TRIAL REGISTRATION NUMBER: ISRCTN72614272; Post-results.

How do we use ambulatory measurement of blood pressure in the management of hypertension?

We have explored the use and interpretation of ambulatory blood pressure monitoring (ABPM) among clinicians at an Edinburgh Cardiovascular Risk Clinic and among a group of international experts in blood pressure monitoring. Locally, we were able to demonstrate major discrepancies in management advice between doctors and nurses. Although all of the international experts used ABPM regularly, they did not agree on thresholds levels for treatment or target BP. This gives food for thought as we consider how to advise internists and primary care physicians on the use and interpretation of ABPM.

Methodology and technology for peripheral and central blood pressure and blood pressure variability measurement: current status and future directions - Position statement of the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability.

Office blood pressure measurement has been the basis for hypertension evaluation for almost a century. However, the evaluation of blood pressure out of the office using ambulatory or self-home monitoring is now strongly recommended for the accurate diagnosis in many, if not all, cases with suspected hypertension. Moreover, there is evidence that the variability of blood pressure might offer prognostic information that is independent of the average blood pressure level. Recently, advancement in technology has provided noninvasive evaluation of central (aortic) blood pressure, which might have attributes that are additive to the conventional brachial blood pressure measurement. This position statement, developed by international experts, deals with key research and practical issues in regard to peripheral blood pressure measurement (office, home, and ambulatory), blood pressure variability, and central blood pressure measurement. The objective is to present current achievements, identify gaps in knowledge and issues concerning clinical application, and present relevant research questions and directions to investigators and manufacturers for future research and development (primary goal).

Do SpaceLabs ambulatory non-invasive blood pressure recorders measure blood pressure consistently over several years use?

OBJECTIVE: To assess the measurement consistency of SpaceLabs ambulatory recorders (Spacelabs, Washington, USA) that are in regular use. METHODS: A total of 14 SpaceLabs 90207 and one 90217 ambulatory recorders were tested for measurement consistency using the Dynatech CuffLink (Dynatech, Nevada, USA), a commercially available non-invasive blood pressure (NIBP) simulator. The NIBP recorders were tested at a range of pressures with 20 repeated determinations at a simulated 120/80 mmHg and five repeated determinations at simulated pressures of 80/50, 100/80, 150/100, 200/165 and 250/195 mmHg. Tests were carried out in 1998, 2002 and late 2003 or early 2004. CONCLUSIONS: All 15 SpaceLabs recorders measured consistently over the 6 years with 89.5% of the differences in average pressures, recorded by any particular device at each recorded pressure, less than 2 mmHg between successive test episodes. The maximum difference was 4.5 mmHg and 60.1% of the differences were less than 1 mmHg. The measurements for all devices were within the tolerances specified by the supplier for the device when tested with the simulator. Maintenance records also show that most devices required breakdown maintenance less than once every 3 years. The results show that the SpaceLabs devices maintain measurement consistency in the demanding conditions of ambulatory pressure recording over several years.

Mixed methods feasibility study for a trial of blood pressure telemonitoring for people who have had stroke/transient ischaemic attack (TIA).

BACKGROUND: Good blood pressure (BP) control reduces the risk of recurrence of stroke/transient ischaemic attack (TIA). Although there is strong evidence that BP telemonitoring helps achieve good control, none of the major trials have considered the effectiveness in stroke/TIA survivors. We therefore conducted a feasibility study for a trial of BP telemonitoring for stroke/TIA survivors with uncontrolled BP in primary care. METHOD: Phase 1 was a pilot trial involving 55 patients stratified by stroke/TIA randomised 3:1 to BP telemonitoring for 6 months or usual care. Phase 2 was a qualitative evaluation and comprised semi-structured interviews with 16 trial participants who received telemonitoring and 3 focus groups with 23 members of stroke support groups and 7 carers. RESULTS: Overall, 125 patients (60 stroke patients, 65 TIA patients) were approached and 55 (44%) patients were randomised including 27 stroke patients and 28 TIA patients. Fifty-two participants (95%) attended the 6-month follow-up appointment, but one declined the second daytime ambulatory blood pressure monitoring (ABPM) measurement resulting in a 93% completion rate for ABPM - the proposed primary outcome measure for a full trial. Adherence to telemonitoring was good; of the 40 participants who were telemonitoring, 38 continued to provide readings throughout the 6 months. There was a mean reduction of 10.1 mmHg in systolic ABPM in the telemonitoring group compared with 3.8 mmHg in the control group, which suggested the potential for a substantial effect from telemonitoring. Our qualitative analysis found that many stroke patients were concerned about their BP and telemonitoring increased their engagement, was easy, convenient and reassuring. CONCLUSIONS: A full-scale trial is feasible, likely to recruit well and have good rates of compliance and follow-up. TRIAL REGISTRATION: ISRCTN61528726 15/12/2011.

Ten years on: Safety of short synacthen tests in assessing adrenocorticotropin deficiency in clinical practice.

Since 1988, when a retrospective study of patients attending this unit was published, we have advocated the use of the short synacthen test (SST) as the primary screening investigation to detect ACTH deficiency. However, others have published comparisons of SST and insulin tolerance tests that suggest a significant false negative rate with SST, leading to concern that some patients who pass the SST are in danger from the clinical consequences of ACTH deficiency. To address this, we audited biochemical results and clinical outcome in 63 patients who did not have ACTH deficiency detected (i.e. who passed the test) by SST after pituitary surgery. Twelve of the 63 patients who passed a SST after pituitary surgery became ACTH-deficient later as diagnosed by SST: 4 within the first year, 2 of whom had received postoperative radiotherapy (3 had symptoms of tiredness and 1 was admitted to the hospital with a viral infection); 8 in yr 3-5, 7 of whom had received postoperative radiotherapy (all had either no symptoms or symptoms of tiredness alone). Thus, the predictive value of the SST in excluding ACTH deficiency is approximately 97% (2 of 63 patients who initially passed the SST were found to be ACTH-deficient within 12 months without having received postoperative radiotherapy). Only 1 patient was ill enough to require hospital admission. Setting the risk of false negatives with SST against the morbidity and manpower implications associated with insulin tolerance tests, SST remains the primary screening test for ACTH deficiency in our practice. However, a high index of clinical suspicion to detect false negative results must be maintained.

Self-monitored blood pressure: a role in clinical practice?

Electronic self-monitoring of blood pressure is increasing in popularity and most international guidelines on the management of hypertension approve cautious use of the technique in the assessment of potentially hypertensive individuals. A recent editorial in the Archives of Internal Medicine suggested that it was "appropriate to encourage the widespread use of self recorded BP as an important adjunct to the clinical care of the patient with hypertension". Such a statement is based on increasing evidence that self-monitoring of blood pressure gives similar information to daytime ambulatory blood pressure -- a now well-established technology in the management of hypertension. Suggested strategies for the use of self-monitoring of blood pressure include monitoring in individuals whose clinical risk status is low enough that they need not necessarily be given medical therapy simply on the basis of a clinic pressure (i.e. at a 10 year risk of cardiovascular disease below 20%). The threshold for defining 'normotension/hypertension' is now regarded as being broadly similar for ABPM and SBPM and is set at 135/85 mmHg. In a recent meta-analysis of all available studies the average difference between these techniques, using the same patients, is -1.7/1.2 mmHg. There is some evidence that careful use of self-monitoring may improve blood pressure control in patients who are otherwise resistant to care. Self-monitoring of blood pressure has now been shown in at least one major prospective study to predict outcome better than clinic pressures and in that setting it now has equivalence to the use of ABPM. There remain issues regarding the availability of validated devices, the quality of training of patients in their use and the possibility that inaccurate recording might occur, either deliberately or by accident. Self-monitoring of blood pressure may well not give the same readings as carefully measured blood pressure by research nurses but its use is clearly superior to routine clinical practice. The technique is ripe for widespread application.

The impact of supported telemetric monitoring in people with type 2 diabetes: study protocol for a randomised controlled trial.

BACKGROUND: Diabetes prevalence is increasing and current methods of management are unsustainable. Effective approaches to supporting self-management are required. The aim of this randomized controlled trial is to establish whether supported telemetric monitoring of glycemic control and blood pressure results in reductions in glycosylated hemoglobin (HbA1c; the primary outcome of a measure of long-term glycemic control) and secondary outcomes of blood pressure and weight among people with poorly controlled diabetes compared to a control group receiving usual care. METHODS/DESIGN: Design: multi-center, randomized controlled trial with embedded qualitative study. Setting: primary care in Lothian, Kent, Glasgow and Borders regions in the UK. Participants: people with type 2 diabetes and confirmed HbA1c>7.5% (58 mmol/mol). Intervention/comparison: randomization to intervention or control groups will be performed by the Edinburgh Clinical Trials Unit. Participants in the intervention group will be shown how to use blood glucose and blood pressure monitors and weighing scales which use Bluetooth wireless technology to transmit readings via modem to a remote server. These participants will be asked to provide at least twice weekly measurements of morning and evening blood glucose and weekly measurements of weight and blood pressure. Measurements will be checked at least weekly by practice nurses who will contact the patients to adjust therapy according to guidelines and reinforce lifestyle advice. Participants in the control group will receive usual care. All participants will receive an individual education session. Follow-up: measurements will be performed at practices 9 months after randomization by research nurses blinded to allocation. The primary outcome measure is HbA1c and secondary outcomes measure are daytime systolic and diastolic blood pressure, weight and cost per quality-adjusted life year. Analysis: intention-to-treat analyses will be performed. The sample size of 320 participants allows for 20% drop-out and has 80% power at 5% significance to detect a 0.5% absolute (6 mmol/mol) fall in HbA1c in the intervention group. The qualitative study will explore the experiences of patients and professionals using the intervention. TRIAL REGISTRATION: Trial registration number ISRCTN71674628.

Telemonitoring based service redesign for the management of uncontrolled hypertension: multicentre randomised controlled trial.

OBJECTIVE: To determine if an intervention consisting of telemonitoring and supervision by usual primary care clinicians of home self measured blood pressure and optional patient decision support leads to clinically important reductions in daytime systolic and diastolic ambulatory blood pressure in patients with uncontrolled blood pressure. DESIGN: Multicentre randomised controlled trial. SETTING: 20 primary care practices in south east Scotland. PARTICIPANTS: 401 people aged 29-95 years with uncontrolled blood pressure (mean daytime ambulatory measurement ≥ 135/85 mm Hg but ≤ 210/135 mm Hg). INTERVENTION: Self measurement and transmission of blood pressure readings to a secure website for review by the attending nurse or doctor and participant, with optional automated patient decision support by text or email for six months. MAIN OUTCOME MEASURES: Blinded assessment of mean daytime systolic ambulatory blood pressure six months after randomisation. RESULTS: 200 participants were randomised to the intervention and 201 to usual care; primary outcome data were available for 90% of participants (182 and 177, respectively). The mean difference in daytime systolic ambulatory blood pressure adjusted for baseline and minimisation factors between intervention and usual care was 4.3 mm Hg (95% confidence interval 2.0 to 6.5; P=0.0002) and for daytime diastolic ambulatory blood pressure was 2.3 mm Hg (0.9 to 3.6; P=0.001), with higher values in the usual care group. The intervention was associated with a mean increase of one general practitioner (95% confidence interval 0.5 to 1.6; P=0.0002) and 0.6 (0.1 to 1.0; P=0.01) practice nurse consultations during the course of the study. CONCLUSIONS: Supported self monitoring by telemonitoring is an effective method for achieving clinically important reductions in blood pressure in patients with uncontrolled hypertension in primary care settings. However, it was associated with increase in use of National Health Service resources. Further research is required to determine if the reduction in blood pressure is maintained in the longer term and if the intervention is cost effective. TRIAL REGISTRATION: Current Controlled Trials ISRCTN72614272.

Telemonitoring-based service redesign for the management of uncontrolled hypertension (HITS): cost and cost-effectiveness analysis of a randomised controlled trial.

OBJECTIVES: To compare the costs and cost-effectiveness of managing patients with uncontrolled blood pressure (BP) using telemonitoring versus usual care from the perspective of the National Health Service (NHS). DESIGN: Within trial post hoc economic evaluation of data from a pragmatic randomised controlled trial using an intention-to-treat approach. SETTING: 20 socioeconomically diverse general practices in Lothian, Scotland. PARTICIPANTS: 401 primary care patients aged 29-95 with uncontrolled daytime ambulatory blood pressure (ABP) (≥135/85, but <210/135 mm Hg). INTERVENTION: Participants were centrally randomised to 6 months of a telemonitoring service comprising of self-monitoring of BP transmitted to a secure website for review by the attending nurse/doctor and patient, with optional automated patient decision-support by text/email (n=200) or usual care (n-201). Randomisation was undertaken with minimisation for age, sex, family practice, use of three or more hypertension drugs and self-monitoring history. MAIN OUTCOME MEASURES: Mean difference in total NHS costs between trial arms and blinded assessment of mean cost per 1 mm Hg systolic BP point reduced. RESULTS: Home telemonitoring of BP costs significantly more than usual care (mean difference per patient £115.32 (95% CI £83.49 to £146.63; p<0.001)). Increased costs were due to telemonitoring service costs, patient training and additional general practitioner and nurse consultations. The mean cost of systolic BP reduction was £25.56/mm Hg (95% CI £16.06 to £46.89) per patient. CONCLUSIONS: Over the 6-month trial period, supported telemonitoring was more effective at reducing BP than usual care but also more expensive. If clinical gains are maintained, these additional costs would be very likely to be compensated for by reductions in the cost of future cardiovascular events. Longer-term modelling of costs and outcomes is required to fully examine the cost-effectiveness implications. TRIAL REGISTRATION: International Standard Randomised Controlled Trials, number ISRCTN72614272.