A mobile health intervention combining remote monitoring and structured video consultations may be associated with a reduced risk of cardiovascular mortality or worsening heart failure compared with usual care among patients recently hospitalized for heart failure.

In a 24-week, multicenter, open-label phase 3 trial, researchers evaluated the addition of mobile health technology to established heart failure management during the early postdischarge period among 506 adults across 9 hospitals and 1 primary care service in Spain between May 2018 and April 2022. Eligible patients had been hospitalized for heart failure decompensation and were preparing for discharge or had been discharged within the preceding 30 days.

The researchers randomly assigned the patients to undergo mobile health management (n = 255) or usual care (n = 251). Clinical endpoints were adjudicated by a committee masked to treatment assignment.

The mobile health intervention combined daily transmission of blood pressure, heart rate, and body weight with symptom questionnaires completed through a smartphone application. Health care teams reviewed transmitted data, received automated alerts for abnormal findings or missing information, and conducted planned or unplanned video consultations.

Usual care followed established heart failure management protocols at each center, including nurse-led education, symptom monitoring, and face-to-face follow-up. Guideline-directed treatment adjustments were encouraged in both groups.

The primary endpoint was time to first cardiovascular mortality or worsening heart failure event. Qualifying worsening heart failure events involved acute decompensation requiring intravenous decongestive therapy in an outpatient or emergency setting, unplanned hospitalization, or decompensation complicating another hospital admission.

The primary composite endpoint occurred in 17% (n = 43/255) of the patients assigned to mobile health management and 41% (n = 102/251) of those assigned to usual care. There was a 65% relative reduction in the likelihood of a first event and a number needed to treat of 3.8.

Both components of the primary endpoint favored the intervention. Worsening heart failure occurred in 14% (n = 36) receiving mobile health management vs. 39% (n = 99) receiving usual care. Cardiovascular mortality occurred in 4% (n = 10) vs. 8% (n = 20), respectively.

Heart failure hospitalization occurred in 7% receiving mobile health management vs. 20% receiving usual care. Urgent heart failure visits occurred in 7% vs. 18%, cardiovascular hospitalizations in 11% vs. 23%, and all-cause hospitalizations in 22% vs. 34%.

All-cause mortality was 6% in the intervention group and 11% in the usual care group. Noncardiovascular hospitalization and noncardiovascular mortality did not differ significantly.

An analysis events identified 64 first and recurrent events in the intervention group vs. 168 in the usual care group. Recurrent-event modeling and sensitivity analyses accounting for potential clustering by study center were consistent with the primary findings.

The effect on the primary composite endpoint was consistent across prespecified subgroups defined by age, frailty, heart failure classification, functional status, comorbidities, literacy, and technology skills.

Among patients aged 75 years or older, the endpoint occurred in 21% receiving mobile health management vs. 48% receiving usual care. Among patients classified as frail, the corresponding proportions were 19% and 53%.

Event proportions favored mobile health management among patients with reduced ejection fraction (13% vs. 32%) and preserved ejection fraction (21% vs. 52%).

The researchers identified heterogeneity by sex, with a larger relative treatment effect among women. The primary endpoint occurred in 14% of women receiving mobile health management vs. 49% receiving usual care compared with 19% vs. 36% among men. A post hoc analysis identified heterogeneity according to heart failure care setting.

Mobile health management was associated with greater improvements in patient-reported self-care and health status. Self-care scores improved from 31 to 18 with mobile health management and from 30 to 20 with usual care.

Patients receiving mobile health management had more unplanned contact with health care teams. In post hoc analyses, more episodes of worsening heart failure were managed through increased oral diuretics in the intervention group, whereas ambulatory intravenous or subcutaneous furosemide was more frequent with usual care.

During follow-up, the mobile health platform generated 11,012 alerts. Mean adherence was 77% for biometric data transmission and 67% for daily symptom questionnaires.

Assigned follow-up ended prematurely for 20% (n = 51) of patients in the intervention group. Fourteen patients were unwilling to continue using the technology, and another 14 were unable to use it. All randomized patients remained included in the primary intention-to-treat analysis.

The researchers acknowledged limitations related to the open-label design, the absence of systematically collected adverse-event data, and the lack of ethnicity information. The trial was not designed to systematically assess intervention-related safety.

The study enrolled slightly fewer patients than its calculated sample size of 508. Differences in standard care across participating centers could have introduced variability, although sensitivity analyses accounting for center-level clustering were consistent with the primary findings.

The researchers did not systematically evaluate alarm response times, staffing requirements, training needs, or the effects of additional alerts and unplanned contacts on clinical workflows. All participating centers had established heart failure management programs, and the operational requirements for broader implementation remain to be determined.

The trial began before sodium-glucose cotransporter 2 inhibitors and vericiguat were included in heart failure treatment guidelines, and their use was not collected.

"Studies to establish the full requirements of implementing [mobile health technology] for heart failure healthcare teams are ... warranted," wrote lead study author Sergi Yun, MD, of the University of Barcelona, and colleagues.

The study authors declared no conflicts of interest.

Source: Lancet Digital Health