Upper vs. Lower Body Aerobic Training in Patients with Claudication

Diane Treat-Jacobson, PhD, RNDiane Treat-Jacobson, PhD, RNAssistant Professor of NursingAssistant Professor of NursingCenter for Gerontological NursingCenter for Gerontological Nursing

Peripheral Arterial DiseasePeripheral Arterial Diseaseand Claudicationand Claudication

Peripheral Arterial DiseasePeripheral Arterial Disease (PAD) (PAD)A disorder caused by atherosclerosis A disorder caused by atherosclerosis that limits blood flow to the limbsthat limits blood flow to the limbs

ClaudicationClaudication A symptom of PAD characterized by A symptom of PAD characterized by pain, aching, or fatigue in working pain, aching, or fatigue in working skeletal muscles. Claudication arises skeletal muscles. Claudication arises when there is insufficient blood flow to when there is insufficient blood flow to meet the metabolic demands of meet the metabolic demands of working skeletal muscles working skeletal muscles

Exercise Training for Exercise Training for ClaudicationClaudication• Efficacy of treadmill training to

improve walking distance in patients with claudication from is well established

• Mechanisms by which exercise training improves walking distance have not been fully elucidated

What is the mechanism of What is the mechanism of improvement in walking improvement in walking distance?distance? Local conditioning effect – changes Local conditioning effect – changes

in muscle metabolism stimulated in muscle metabolism stimulated by exercising specific muscles by exercising specific muscles affected by limited blood flowaffected by limited blood flow

Systemic effect – changes in Systemic effect – changes in central cardiovascular conditioning central cardiovascular conditioning and/or vascular function, leading and/or vascular function, leading to improved walking abilityto improved walking ability

Exercise Training for Exercise Training for ClaudicationClaudication There is limited information about the There is limited information about the

potential of aerobic arm training to improve potential of aerobic arm training to improve onset to claudication (OCD) distance and onset to claudication (OCD) distance and maximal walking distance (MWD)maximal walking distance (MWD)

One study demonstrated equivalent benefit One study demonstrated equivalent benefit of upper and lower extremity cycle of upper and lower extremity cycle ergometry exercise on walking distance ergometry exercise on walking distance (Walker et. al, 2000) (Walker et. al, 2000)

No previous studies have compared aerobic No previous studies have compared aerobic arm training to treadmill training in patients arm training to treadmill training in patients with claudicationwith claudication

Potential Mechanisms by Which Potential Mechanisms by Which Exercise Improves ClaudicationExercise Improves Claudication

Peripheral arterial diseaseReduced oxygen delivery

: Ischemia-Reperfusion

Poor aerobic capacity Reduced muscle strength & endurance

Impaired walking ability Decreased quality of life

Deconditioning and worsening:Obesity

Hypertension Hyperlipidemia Hyperglycemia Thrombotic risk

Effects of exercise training on pathophysiological correlates of claudication Good evidence for improvement Potential improvement Short-term: may worsen Long-term: may improve

Systemic inflammation

Muscle fiber denervation Muscle fiber atrophy

Altered muscle metabolism

Endothelial Dysfunction

Stewart et al. Medical Progress: Exercise Training for Claudication. NEJM 2002; 347(24):1941-1951

Exercise Training for Exercise Training for Claudication StudyClaudication Study**

Specific Aims:Specific Aims:– Determine the relative efficacy of Determine the relative efficacy of

supervised treadmill training or arm supervised treadmill training or arm ergometry alone, or in combination, ergometry alone, or in combination, versus ‘usual care’ in subjects with PADversus ‘usual care’ in subjects with PAD

– Evaluate the extent to which the effects Evaluate the extent to which the effects are maintained or improved following are maintained or improved following completion of supervised programcompletion of supervised program

**Funded by a American Heart Association Scientist Development GrantFunded by a American Heart Association Scientist Development Grant

MethodsMethods

Randomized controlled pretest-Randomized controlled pretest-posttest designposttest design

4 groups4 groups– Treadmill trainingTreadmill training– Upper extremity ergometryUpper extremity ergometry– Combined trainingCombined training– Control GroupControl Group

Entry CriteriaEntry Criteria

InclusionInclusion– Age Age >> 18 years 18 years– Resting ABI Resting ABI << 0.90 0.90

or 20% drop in or 20% drop in post-exercise ABIpost-exercise ABI

– Lifestyle limitation Lifestyle limitation due to claudicationdue to claudication

– Ability to complete Ability to complete study proceduresstudy procedures

ExclusionExclusion– Uncontrolled Uncontrolled

hypertension or hypertension or diabetesdiabetes

– Recent peripheral or Recent peripheral or coronary coronary revascularization revascularization procedureprocedure

– Fontaine stage 3 (rest Fontaine stage 3 (rest pain) or 4 (tissue loss)pain) or 4 (tissue loss)

– Unstable heart diseaseUnstable heart disease– Walking limited by Walking limited by

factors than factors than claudicationclaudication

ProceduresProcedures

Screening VisitScreening Visit– Informed consentInformed consent– Medical History & Physical Exam, Medical History & Physical Exam,

including ankle brachial index (ABI)including ankle brachial index (ABI)– Quality of life and health status Quality of life and health status

questionnairesquestionnaires– Symptom-limited graded cardiopulmonary Symptom-limited graded cardiopulmonary

treadmill exercise test (x2)treadmill exercise test (x2)– Post-Exercise ABIPost-Exercise ABI– Baseline arm ergometry testBaseline arm ergometry test

Exercise GroupsExercise Groups

Supervised in the exercise Supervised in the exercise laboratory 3 times/week for 12 laboratory 3 times/week for 12 weeksweeks

Sessions 70 minutes in length, 5 Sessions 70 minutes in length, 5 minutes warm-up, 60 minutes of minutes warm-up, 60 minutes of exercise, 5 minutes cool downexercise, 5 minutes cool down

Recording of daily exercise Recording of daily exercise outside supervised settingoutside supervised setting

Treadmill Exercise Treadmill Exercise ProgramProgram Treadmill walking Treadmill walking Speed: 2.0 mphSpeed: 2.0 mph Grade increased by 0.5% every 8 Grade increased by 0.5% every 8

minutes until onset of moderate minutes until onset of moderate claudication (rating: 4 out of 5)claudication (rating: 4 out of 5)

After 7% grade is reached, increase After 7% grade is reached, increase speed at 0.1 MPH intervalsspeed at 0.1 MPH intervals

Time: 60 minutes including rest Time: 60 minutes including rest periodsperiods

Upper Body Exercise Upper Body Exercise ProgramProgram Arm Ergometry Arm Ergometry Watts start at one level below Watts start at one level below

maximal testmaximal test 2 minutes exercise, 2 minutes rest2 minutes exercise, 2 minutes rest Gradually increase watts, exercise-Gradually increase watts, exercise-

rest intervals throughout program as rest intervals throughout program as tolerated tolerated

Time: 60 minutes including rest Time: 60 minutes including rest periodsperiods

Combination Exercise Combination Exercise ProgramProgram

20 minutes Arm Ergometry 20 minutes Arm Ergometry 40 minutes Treadmill40 minutes Treadmill Increase intensity as with other Increase intensity as with other

protocolsprotocols Time: 60 minutes including rest Time: 60 minutes including rest

periodsperiods

Control GroupControl Group

Instructed to continue ‘usual care’Instructed to continue ‘usual care’ Provided specific written walking Provided specific written walking

instructionsinstructions Instructed on completion of daily Instructed on completion of daily

exercise recordsexercise records Weekly follow-up in the laboratory, Weekly follow-up in the laboratory,

review of exercise recordsreview of exercise records

Post-Training AssessmentPost-Training Assessment

Re-assessment of all outcome Re-assessment of all outcome variables within 1 week of variables within 1 week of completion of training program, completion of training program, or 12 weeks after enrollment for or 12 weeks after enrollment for control groupcontrol group

Follow-up 12 weeks following Follow-up 12 weeks following completion of program (approx. completion of program (approx. 24 weeks) 24 weeks)

Outcome MeasuresOutcome Measures

Walking Distance (pain free, OCD Walking Distance (pain free, OCD and maximal, MWD)and maximal, MWD)

Cardiovascular VariablesCardiovascular Variables

Quality of Life, Functional Status Quality of Life, Functional Status and Moodand Mood

Demographic and Medical VariablesDemographic and Medical Variables

Variable Mean (sd)

Age in Years 67.8 (11.61)

BMI 27.7 (4.32)

Pack Years 36.6 (20.25)

Lowest Resting ABI 0.68 (0.13)

Variable n (%)

Male 18 (64.3)

Diabetes 8 (28.6)

Hypertension 22 (78.6)

Current/Past Smoking 25

(89.3)

Dyslipidemia 26 (92.9)

Leg Revascularizatio

n9 (32.1)

Coronary Heart Disease 18

(64.3)

Median Onset of Claudication Distance (OCD) and Maximal Walking Distance (MWD) Scores at Baseline and Following 12 Weeks of Exercise Training

Training Group Baseline OCD Median (Range)

12 Week OCDMedian (Range)

Wilcoxan Z Score (p)

Treadmill (n=8) 94.3 meters(26.8-482.8)

187.3 meters(78.67-885.1)

2.37 (0.018)

Combination (n=10)

147.1 meters(54.0-268.2)

224.4 meters(80.46-481.0)

1.96 (0.05)

Arm Ergometry (n=6)

132.3 meters(80.0-268.2)

251.2 meters(134.1-482.8)

2.20 (0.028)

Baseline MWD Median (range)

12 Week MWD Median (Range)

Wilcoxan Z Score (p)

Treadmill (n=9) 363.9 meters(320.1-266.8)

764.5 meters(401.0-1402.0)

2.67 (0.008)

Combination (n=10)

475.1 meters(114.4-618.7)

796.5 meters(510.0-970.0)

2.80 (0.005)

Arm Ergometry (n=6)

385.3 meters(319.2-886.9)

665.0 meters(544.0-1080.0)

2.20 (0.028)

Median Change in Onset of Claudication Distance

Baseline 12 Weeks

0

100

200

300

Upper Body Ergometer (n=6)

Treadmill (n=8).

Combination (n=10)Combination (n=10)

Test

Me

ters

Treadmill z= 2.37, p<0.018

Upper Body Ergometer z= 2.20, p<0.028

Combination z= 1.96, p=0.05

Baseline 12 Weeks0

100

200

300

400

500

600

700

Median Change in Maximal Walking Distance

Baseline 12 Weeks0

100

200

300

400

500

600

700

Treadmill (n=9)

Upper Body

Combination (n=10)

Treadmill (n=9)

Upper Body

Combination (n=10)

Treadmill (n=9)

Upper Body Ergometer(n=6)

Combination (n=10)

Test

Met

ers

Treadmill z=2.67, p=0.008

Upper Body Ergometer z=2.20, p=0.028

Combination z=2.80, p=0.005

Treadmill z=2.67, p=0.008

Upper Body Ergometer z=2.20, p=0.028

Combination z=2.80, p=0.005

ConclusionsConclusions

Preliminary data suggest that arm Preliminary data suggest that arm ergometry and treadmill training offer ergometry and treadmill training offer similar benefits in improving OCD and similar benefits in improving OCD and MWD. MWD.

Mechanisms of improvement with both Mechanisms of improvement with both forms of exercise require further study.forms of exercise require further study.

For those with severe PAD who cannot For those with severe PAD who cannot perform walking exercise, arm perform walking exercise, arm exercise is a promising alternative. exercise is a promising alternative.

Future ResearchFuture Research

Preliminary data indicate that there is Preliminary data indicate that there is improvement in those performing upper improvement in those performing upper body aerobic exercise trainingbody aerobic exercise training

This finding suggests a systemic This finding suggests a systemic mechanism of exercise-related mechanism of exercise-related improvementimprovement

Assessment of physiological variables Assessment of physiological variables associated with endothelial injury, associated with endothelial injury, thrombosis/hemostasis, and inflammation thrombosis/hemostasis, and inflammation in those engaging in ischemic versus non-in those engaging in ischemic versus non-ischemic exercise is warrantedischemic exercise is warranted

Functional Consequences

Aerobic Exercise Training

Functional Outcomes

Pathophysiological Changes with Claudication

Arteria l Flow

Cardiac Output

Thrombogenic Activity

Endothelial Injury

Inflammation

Physiological Outcomes with Aerobic Training

Cardiovascular Conditioning

Thrombogenic Activity

Endothelial Injury

Inflammation

Walking ability

Functional Status

Quality of Life

Walking Ability

Functional Status

Quality of Life

A Model of the Impact of Exercise on Patients with Claudication

AcknowledgementsAcknowledgements

Clinical Scholar Clinical Scholar Mentorship TeamMentorship Team– Jean Wyman, Jean Wyman,

PhD, RN, FAANPhD, RN, FAAN– Nigel Key, MDNigel Key, MD– Arthur S. Leon, Arthur S. Leon,

MDMD– Don Dengel, PhDDon Dengel, PhD– Jayne Fulkerson, Jayne Fulkerson,

PhDPhD

Research TeamResearch Team– Ulf Bronas, MSUlf Bronas, MS– Arthur S. Leon, MD Arthur S. Leon, MD – Lora SweezyLora Sweezy– Kristie KochKristie Koch– Kimberly MillerKimberly Miller– Kathryn KochKathryn Koch– Judith Judith

Regensteiner, Regensteiner, ConsultantConsultant