NCT02641418

Brief Summary

Background: Peripheral arterial disease is a result of atherosclerotic occlusion in the major arteries supplying the lower limbs and is associated with an increased risk of mortality and morbidity. It results in restricted blood flow to the skeletal muscles causing intermittent claudication (IC). IC presents as cramp like pain affecting 5% of the population \>50 years and is associated with a substantial reduction in walking capacity, quality of life and diminished physical function. Supervised exercise programmes have been demonstrated to improve maximum walking distances and NICE recommends group-based supervised exercise for treating patients with IC. However, there is significant variability in the impact of treatment across studies and little agreement on the underlying mechanism whereby exercise increases functional outcomes. Potential mechanisms include skeletal muscle metabolism, VO2 max, anaerobic threshold and endothelial function. Studies are needed to better understand how exercise improves outcome and in whom, so as to better refine and target the treatment. The participation of patients with IC in exercise programmes is low. The investigators need to understand factors influencing participation so that we can improve the number of patients with IC benefiting from the programme The research consists of two workstreams: Workstream one Objective: Assess the extent to which patient baseline characteristics and candidate physiological mechanisms are associated with clinical improvement in IC patients participating in an exercise programme Patients: Patients with documented IC referred from a Vascular Consultant. Eligible patients will be invited to participate in a 12 week supervised exercise programme. Testing Schedule: Measurements will be recorded at baseline (prior to exercise), immediately after the completion of the exercise programme and then three months after. Measurements include: Baseline characteristics that might predict outcome:

  • Quality of life using the VascuQol questionnaire
  • Clinical indicators of lower limb function: Ankle brachial pressure index (ABPI), intermittent claudication distance (ICD), Maximum walking distance (MWD). Candidate physiological mechanisms
  • Aerobic capacity (VO2 max \& AT)
  • Muscular strength and endurance
  • Muscle morphology (including muscle thickness, pennation angle, fascicle length and elastography)
  • Endothelial function (sheer stress response as measured by flow mediated dilation) Analysis: Regression analysis will be used to explain variation in patient maximum walking distance at 3 months. The regression will use 9 candidate measures of physiological response and 3 baseline measures to explore what mechanism and patient factors may be associated with clinical improvements. 100 patients recruited over 2 years will give a 90% power to detect an additional increase in variability in MWD explained by each candidate measure of around 5% at the a 0.05 significance level. This research will be used to identify which types of exercise may be most influential in improving outcome and in which patients. Workstream two Objective: Explore the reasons behind patients' participation, non-participation in, experience of and adherence to the exercise programme. Study Design: An interview study of patients with IC routinely referred for supervised exercise. Three groups of patients will be invited to participate. Those who:
  • Choose not to participate in the exercise programme (Group A)
  • Agree to participate in the exercise programme (Group B).
  • Agree to participate but discontinue after at least one session (Group C). Semi-structured face-to-face interviews with 20 patients per group, interviews will be conducted using a topic guide to ensure consistency. The format will be flexible to allow participants to generate naturalistic data on what they consider as important and / or successful in terms of outcome. Data will be analysed thematically and managed using Nvivo software - the approach will be inductive and iterative. This research will be used to redesign the current exercise programme to improve participation and so the impact of exercise in patients with IC.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
109

participants targeted

Target at P50-P75 for not_applicable

Timeline
Completed

Started May 2015

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

May 1, 2015

Completed
4 months until next milestone

First Submitted

Initial submission to the registry

August 25, 2015

Completed
4 months until next milestone

First Posted

Study publicly available on registry

December 29, 2015

Completed
1.8 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

October 1, 2017

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

October 1, 2017

Completed
Last Updated

July 31, 2019

Status Verified

July 1, 2019

Enrollment Period

2.4 years

First QC Date

August 25, 2015

Last Update Submit

July 29, 2019

Conditions

Keywords

Exercise

Outcome Measures

Primary Outcomes (1)

  • Patient maximum walking distance

    12 weeks

Study Arms (1)

Exercise

OTHER

only 1 arm to trial

Other: Supervised exercise programme

Interventions

supervised exercise programme

Exercise

Eligibility Criteria

Age45 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Patients with IC not referred for surgery
  • Community dwelling adults aged forty five or over
  • Ankle brachial index ABPI less than 0.9 at rest or a drop of more than 20 after exercise testing
  • Ability to walk unaided
  • English speaking and able to understand simple protocol instructions

You may not qualify if:

  • Participants who are unable to provide informed consent
  • Severe cardiovascular, musculo-skeletal or pulmonary illness precluding participation in the supervised exercise
  • Critical limb ischaemia
  • Active treatment for cancer

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Hull Royal Infirmary

Hull, East Riding Of Yorkshire, HU3 2JZ, United Kingdom

Location

Related Publications (1)

  • Harwood AE, Totty JP, Pymer S, Huang C, Hitchman L, Carradice D, Wallace T, Smith GE, Chetter IC. Cardiovascular and musculoskeletal response to supervised exercise in patients with intermittent claudication. J Vasc Surg. 2019 Jun;69(6):1899-1908.e1. doi: 10.1016/j.jvs.2018.10.065. Epub 2018 Dec 21.

Related Links

MeSH Terms

Conditions

Vascular DiseasesIntermittent ClaudicationMotor Activity

Condition Hierarchy (Ancestors)

Cardiovascular DiseasesPeripheral Arterial DiseasePeripheral Vascular DiseasesSigns and SymptomsPathological Conditions, Signs and SymptomsBehavior

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
DIAGNOSTIC
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER GOV
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 25, 2015

First Posted

December 29, 2015

Study Start

May 1, 2015

Primary Completion

October 1, 2017

Study Completion

October 1, 2017

Last Updated

July 31, 2019

Record last verified: 2019-07

Data Sharing

IPD Sharing
Will not share

Locations