Incorporating intervention fidelity components into randomized controlled trials promoting exercise adherence in heart failure patients

Intervention Fidelity to VITAL Start (Video Intervention to Inspire Treatment Adherence for Life) in a Randomized Controlled Trial Among Women Living With HIV in Malawi

BACKGROUND.

Intervention effectiveness in a randomized controlled trial is attributed to intervention fidelity. Measuring fidelity has increasing significance to intervention research and validity. The purpose of this article is to describe a systematic assessment of intervention fidelity for VITAL Start (Video intervention to Inspire Treatment Adherence for Life)-a 27-minute video-based intervention designed to improve antiretroviral therapy adherence among pregnant and breastfeeding women.

METHOD.

Research Assistants (RAs) delivered VITAL Start to participants after enrolment. The VITAL Start intervention had three components: a pre-video orientation, video viewing, and post-video counseling. Fidelity assessments using checklists comprised self (RA assessment) and observer (Research Officers, also known as ROs) assessment. Four fidelity domains (adherence, dose, quality of delivery, and participant responsiveness) were evaluated. Score scale ranges were 0 to 29 adherence, 0 to 3 dose, 0 to 48 quality of delivery and 0 to 8 participant responsiveness. Fidelity scores were calculated. Descriptive statistics summarizing the scores were performed.

RESULTS.

In total, eight RAs delivered 379 VITAL Start sessions to 379 participants. Four ROs observed and assessed 43 (11%) intervention sessions. The mean scores were 28 (SD = 1.3) for adherence, 3 (SD = 0) for dose, 40 (SD = 8.6) for quality of delivery, and 10.4 (SD = 1.3) for participant responsiveness.

CONCLUSION.

Overall, the RAs successfully delivered the VITAL Start intervention with high fidelity. Intervention fidelity monitoring should be an important element of randomized control trial design of specific interventions to ensure having reliable study results.

The HEART Camp Exercise Intervention Improves Exercise Adherence, Physical Function, and Patient-Reported Outcomes in Adults With Preserved Ejection Fraction Heart Failure

BACKGROUND

Despite exercise being one of few strategies to improve outcomes for individuals with heart failure with preserved ejection fraction (HFpEF), exercise clinical trials in HFpEF are plagued by poor interventional adherence. Over the last 2 decades, our research team has developed, tested, and refined Heart failure Exercise And Resistance Training (HEART) Camp, a multicomponent behavioral intervention to promote adherence to exercise in HF. We evaluated the effects of this intervention designed to promote adherence to exercise in HF focusing on subgroups of participants with HFpEF and heart failure with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

This randomized controlled trial included 204 adults with stable, chronic HF. Of those enrolled, 59 had HFpEF and 145 had HFrEF. We tested adherence to exercise (defined as ≥120 minutes of moderate-intensity [40%-80% of heart rate reserve] exercise per week validated with a heart rate monitor) at 6, 12, and 18 months. We also tested intervention effects on symptoms (Patient-Reported Outcomes Measurement Information System-29 and dyspnea-fatigue index), HF-related health status (Kansas City Cardiomyopathy Questionnaire), and physical function (6-minute walk test). Participants with HFpEF (n = 59) were a mean of 64.6 ± 9.3 years old, 54% male, and 46% non-White with a mean ejection fraction of 55 ± 6%. Participants with HFpEF in the HEART Camp intervention group had significantly greater adherence compared with enhanced usual care at both 12 (43% vs 14%, phi = 0.32, medium effect) and 18 months (56% vs 0%, phi = 0.67, large effect). HEART Camp significantly improved walking distance on the 6-minute walk test (η2 = 0.13, large effect) and the Kansas City Cardiomyopathy Questionnaire overall (η2 = 0.09, medium effect), clinical summary (η2 = 0.16, large effect), and total symptom (η2 = 0.14, large effect) scores. In the HFrEF subgroup, only patient-reported anxiety improved significantly in the intervention group.

CONCLUSIONS

A multicomponent, behavioral intervention is associated with improvements in long-term adherence to exercise, physical function, and patient-reported outcomes in adults with HFpEF and anxiety in HFrEF. Our results provide a strong rationale for a large HFpEF clinical trial to validate these findings and examine interventional mechanisms and delivery modes that may further promote adherence and improve clinical outcomes in this population.

CLINICAL TRIAL REGISTRATION

URL: https://clinicaltrials.gov/. Unique identifier: NCT01658670.