Background & Aims

Findings from large pharmaceutical trials have not altered the progressive course of painful diabetic peripheral neuropathy (P-DPN) leaving a large population suffering with pain and limited treatment options. Exercise-induced pain-threshold modulation (EPM) is a promising tool that provides valuable information on endogenous pain modulation mechanisms via measurement of changes in pain sensitivity pre- and post- exercise. Thus, EPM may be useful for identifying responders to exercise-based physiotherapy interventions. Cardiovascular diseases (CVD) are common amongst patients with P-DPN and current guidelines require maximal graded exercise stress testing with electrocardiogram monitoring (ExSt) prior to participation in exercise. This is a barrier for wide implementation of EPM testing in those with diabetes. The purpose of this secondary analysis is to describe the impact of ExSt guidelines for patients with diabetes on participant enrollment in a study of EPM in patients with P-DPN.

Methods

Patients with P-DPN were recruited from a university-based health system. Screening included chart review, medical history, and vital response to a 6-minute walk test. The American College of Sports Medicine guidelines require ExSt prior to exercising diabetics with any of the following: > 40 years-old, > 30 years-old and 10+ years of diabetes, smoking, hypertension, dyslipidemia, retinopathy, nephropathy, known/suspected coronary or peripheral arterial disease, and autonomic neuropathy. Due to equipment and time constraints, ExSt was not used for this study; thus, participants meeting the criterion above were excluded. Patients who were enrolled participated in 2 EPM sessions consisting of cycling for 20 minutes at an intensity level eliciting a self-reported 6/10 exertion on the Borg Category-Ratio Scale. This scale has strong correlations with oxygen consumption and anaerobic thresholds during exercise.

Results

Fifty-two total patients were contacted for this study. 23.1% were excluded per the American College of Sports Medicine criteria. Of those excluded from this exercise study, a third were currently engaging in exercise programs supervised by physiotherapists without reported adverse events.

Conclusions

Current ExSt guidelines in those with diabetes limited enrollment in this study and may unnecessarily challenge the feasibility of EPM research. ExSt has low sensitivity for predicting if patients with diabetes will have a CVD event (0.47), thus is a poor tool to identify who is safe to exercise. In addition, 33% of those excluded from the study were participating in exercise supervised by physiotherapists, without adverse events, suggesting that ExSt is not necessary for participation in exercise. These strict guidelines are barriers directly affecting the study of EPM and limit our understanding of central nervous system modulation, despite little evidence to support ExSt improves patient safety. Appropriate monitoring of vital signs during and after exercise may be sufficient to ensure participant safety in EPM research. Pain scientists should work with cardiologists to modify current guidelines that largely exclude the patients most likely to benefit.

References

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Presenting Author

Juan P. Gonzalez

Poster Authors

Juan Gonzalez

PT

University of Miami, Department of Physical Therapy, APReCIAT Lab

Lead Author

E-mail

Kathryn Roach PT

PhD

University of Miami, Miller School of Medicine, Department of Physical Therapy

Lead Author

E-mail

Neva Kirk-Sanchez PT

PhD

University of Miami, Miller School of Medicine, Department of Physical Therapy

Lead Author

E-mail

Francesco Vendrame MD

PhD

University of Miami, Miller School of Medicine, Division of Endocrinology Diabetes and Metabolism

Lead Author

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Lawrence Cahalin PT

PhD

University of Miami, Miller School of Medicine, Department of Physical Therapy

Lead Author

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Jadyn Chandler SPT

University of Miami, Miller School of Medicine, Department of Physical Therapy

Lead Author

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Cameron Schmidt SPT

University of Miami, Miller School of Medicine, Department of Physical Therapy

Lead Author

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Tamir Shitrit SPT

University of Miami, Miller School of Medicine, Department of Physical Therapy

Lead Author

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Mark Bishop PT

PhD

University of Florida, College of Public Health & Health Professions, Department of Physical Therapy

Lead Author

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Marlon Wong

PT

University of Miami

Lead Author

E-mail

Topics

  • Specific Pain Conditions/Pain in Specific Populations: Neuropathic Pain - Peripheral

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