Challenges in recruitment and adherence to a randomized clinical trial in Brazil on the effects of transcutaneous nervous electrical stimulation on individuals with peripheral arterial disease: A feasibility study

Abstract

Describe the feasibility, barriers during the recruitment and intervention period, recruitment rate (success and efficiency), and the level of participation and adherence in the randomized clinical trial to verify the effects of transcutaneous electrical nerve stimulation (TENS) for the symptoms of intermittent claudication (IC) and its repercussions on functional capacity, cardiorespiratory fitness and cardiovascular autonomic function in individuals with sta II Fontaine classification, residing in Brazil. Prospective, double-blind, randomized clinical trial. Level secondary. A total of 63 participants were screened, of which 12.6% were included. Eight individuals with peripheral arterial disease (PAD) and IC underwent a protocol that lasted 8weeks. The experimental group received 45minutes TENS 10Hz, followed by 30minutes of aerobic exercise, and the control group received a placebo TENS also followed by 30minutes of exercise. Incremental walking test, gait impairment questionnaire, treadmill test, heart rate variability, and 4-second test were applied, considering adherence, success, and efficiency. The most efficient recruitment sources were as follows: 1) referral by physician and 2) referral by a physiotherapist. Out of 63 participants, 8 (12.6%) were included in the clinical trial. Participants were excluded due to the following reasons: not meeting the criteria (41 participants (65%)), locomotion (6 participants (9.5%)), transportation (5 participants (7.9%)), work release (1 participant (1.6%)), and interest (2 participants (3.2%)). The overall participation was 99 participants (51.6%) in a total of 192 sessions offered. It was not possible to succeed in recruitment and adherence rates. The results of this clinical trial reinforce that PAD is neglected, and strategies including a multidisciplinary approach with the effective participation of nursing, physiotherapy, medicine, and nutrition professionals, are necessary to optimize care for individuals with PAD need to be strengthened. Brazilian Registry of Clinical Trials (RBR-8RTZFN).