Some positive effects seen but no decrease in pain intensity was observed….
A common complication of diabetes is painful diabetic peripheral neuropathy (P-DPN). Current standard of care for patients with P-DPN involves pharmacological interventions that are limited by their potential adverse side effects. Numerous drugs are still being developed and studied each year along with novel therapies for the treatment of P-DPN. Many studies have documented the beneficial effects of exercise in diabetes, but none has studied its effect on P-DPN. In this study, University of Kansas Medical Center researchers examined the effect of aerobic exercise on pain and patient interference in the daily lives of people with DPN.
Individuals were recruited for the study if they were between 40-70 years of age, diagnosed with T2DM, diagnosed with DPN or had signs/symptoms consistent with neuropathy, and were determined sedentary (under-active) using the Telephone Assessment of Physical Activity (TAPA). There was no control group; each participant was part of the exercise intervention where they participated in three-supervised aerobic exercises each week for 16 weeks. The primary outcomes were pain and pain interference, which were measured by the Brief Pain Inventory Short Form for DPN (BPI-DPN) that consists of four pain intensity items (worst in past 24 hours, least in past 24 hours, average, and current pain severity) and 7 item pain interference scale (impact of DNP on quality of life, described by general activity, mood, sleep, walking ability, relationships, and enjoyment of life in the past 24 hours). Secondary outcomes includes BMI, aerobic fitness (using VO2max), blood pressure, and glycemic control (using A1c).
A total of 20 people were enrolled into the study, but only 18 completed the intervention. Participants included patients with both nonpainful DPN (n=3) and painful DPN (n=15). There were no significant changes in pain intensity; however, pain interference was significantly reduced in walking, normal work, relationship with others, and sleep. General activity, mood, and enjoyment of life did not change. Overall interference (average of all 7 pain interference scale) was significantly reduced after the exercise intervention. Aerobic fitness showed a moderate significant improvement, while BMI, blood pressure, and HbA1c had no significant changes.
The authors concluded that while the participant’s perceived pain intensity did not change, the participants felt less interference in their life after the 16-week exercise intervention. The absence of significant changes in pain intensity but decrease in pain interferences may suggest a psychological component. The authors also acknowledge that the study had several limitations, including a small sample size and a lack of a control group. A potential difference in outcomes could have resulted if adherence to protocol and a longer duration was tested for; the researchers did not include a measure of “coping with pain,” which is possible if the participants learned to cope better with DPN. The results may not be generalizable to many people with P-DPN and certain comorbidities, making it less applicable to the wider population; lastly, further randomized studies need to be conducted to confirm these findings.
- The study examines the effect of aerobic exercise on people with P-DPN.
- There were significant changes in pain interference, but not in pain intensity.
- Further studies are needed, but the pilot study suggests that aerobic exercise can have some beneficial effect in patients with P-DPN.
Yoo M, D’Silvia LJ, Martin P, Sharma N, et al. Pilot study of Exercise Therapy on Painful Diabetic Peripheral Neuropathy. Pain Medicine. 20 March 2015. Web. 14 April 2015.