Exercise Therapy In Patients With Peripheral Neuropathy

Abstract

Peripheral neuropathy is a pathology associated with damage to peripheral nerves, especially those of the extremities. Common symptoms of this condition include weakness, numbness, abnormal sensations and pain in feet, legs, arms, and/or hands. A recent literature search concluded there is inadequate evidence to evaluate the effects of exercise on functional ability in people with peripheral neuropathy. PURPOSE The primary objective was to assess the influence of exercise therapy on peripheral blood flow responses, heart rate variability and functional measures in a small sample of individuals with peripheral neuropathy. METHODS Participants engaged in an organized progressive exercise program 3*week for six weeks. The exercise program consisted of a typical walking program (with or without partial body weight support) or Tai Chi. Leg blood flow was evaluated, in both legs, at rest and following 5 minutes of arterial occlusion, using strain gauge plethysmography. Heart rate variability indices included standard deviation (SDNN), and low frequency (LF) and high frequency (HF) powers determined from EKG's obtained during 10 minutes of uninterrupted supine rest. Postural stability was defined as the average sway velocity in varied conditions on a force platform. Dynamic gait capability was defined as the center of pressure motion during walking on a treadmill. RESULTS To this point sixteen individuals (9 Women and 7 Men, Age: 68±7yrs, Height: 167±9cm, and Weight: 85±16kg) completed the exercise program. The program was well tolerated. No apparent differences in blood flow responses between the left and right legs were noted prior to the program. After 6 weeks, systolic blood pressure decreased (Pre: 135±15 Post: 126±14mmHg, p=0.001), whereas reactive hyperemic blood flow (RHBF) increased (Pre: 16.77±8.16 Post: 20.26±6.45ml/100ml/min, p=0.05). Moreover, changes in measures of heart rate variability suggest a favorable shift in autonomic modulation of the heart (Pre: LF/HF: 2.97±2.42 Post: 2.11±2.05, p=0.03). Finally, the changes in RHBF were associated with changes in SDNN (r2=0.39). Measures of postural stability improved significantly, whereas measures of dynamic gait capability only improved in those individuals involved in the walking program. CONCLUSION The results suggest that progressive exercise therapy is well tolerated in patients with peripheral neuropathy and may improve RHBF, HRV and postural stability. Improvements of measures of dynamic gait capability were specific to the modality of training used.