Long-Term Follow-up of a Randomized Controlled Trial Evaluating a Mobile Health Intervention for Self-Management in Lung Transplant Recipients

Abstract

Mobile health interventions may help transplant recipients follow their complex medical regimens. Pocket Personal Assistant for Tracking Health (Pocket PATH) is one such intervention tailored for lung transplant recipients. A randomized controlled trial showed Pocket PATH's superiority to usual care for promoting the self-management behaviors of adherence, self-monitoring and communication with clinicians during posttransplant year 1. Its long-term impact was unknown. In this study, we examined associations between Pocket PATH exposure during year 1 and longer term clinical outcomes-mortality and bronchiolitis obliterans syndrome (BOS)-among 182 recipients who survived the original trial. Cox regression assessed whether (a) original group assignment and (b) performance of self-management behaviors during year 1 predicted time to outcomes. Median follow-up was 5.7 years after transplant (range 4.2-7.2 years). Pocket PATH exposure had no direct effect on outcomes (p-values >0.05). Self-monitoring was associated with reduced mortality risk (hazard ratio [HR] 0.45; 95% confidence interval [CI] 0.22-0.91; p = 0.027), and reporting abnormal health indicators to clinicians was associated with reduced risks of mortality (HR 0.15; 95% CI 0.04-0.65; p = 0.011) and BOS (HR 0.27; 95% CI 0.08-0.86; p = 0.026), regardless of intervention group assignment. Although Pocket PATH did not have a direct impact on long-term outcomes, early improvements in self-management facilitated by Pocket PATH may be associated with long-term clinical benefit.

Keywords: allied health/nursing; bronchiolitis obliterans (BOS); clinical research/practice; compliance/adherence; lung transplantation/pulmonology; patient survival; social sciences.

Figure 1

Flow of participants from the original Pocket PATH RCT to the present long-term follow-up study. Participants enrolled, randomized and followed-up in the original RCT are denoted in the Enrollment, Allocation and Follow-up sections of the figure, respectively. Participants who survived to the end of the original RCT and were included in the present long-term follow-up study are denoted in the Analysis section of the figure.

Figure 2

Cox regression curves depicting patient survival over the long-term follow-up period. Each curve includes subjects regardless of intervention assignment but represents a different frequency of self-monitoring during the original trial (dashed line: self-monitored on <25% of days; dot-dashed line: self-monitored on 25–<50% of days; solid line: self-monitored on ≥50% of days). P values refer to the test of significance between the curves indicated with each bracket.