Therapeutic advances in restless legs syndrome (RLS)

Association between Chronic Pain and Alterations in the Mesolimbic Dopaminergic System

Chronic pain (pain lasting for >3 months) decreases patient quality of life and even occupational abilities. It can be controlled by treatment, but often persists even after management. To properly control pain, its underlying mechanisms must be determined. This review outlines the role of the mesolimbic dopaminergic system in chronic pain. The mesolimbic system, a neural circuit, delivers dopamine from the ventral tegmental area to neural structures such as the nucleus accumbens, prefrontal cortex, anterior cingulate cortex, and amygdala. It controls executive, affective, and motivational functions. Chronic pain patients suffer from low dopamine production and delivery in this system. The volumes of structures constituting the mesolimbic system are known to be decreased in such patients. Studies on administration of dopaminergic drugs to control chronic pain, with a focus on increasing low dopamine levels in the mesolimbic system, show that it is effective in patients with Parkinson’s disease, restless legs syndrome, fibromyalgia, dry mouth syndrome, lumbar radicular pain, and chronic back pain. However, very few studies have confirmed these effects, and dopaminergic drugs are not commonly used to treat the various diseases causing chronic pain. Thus, further studies are required to determine the effectiveness of such treatment for chronic pain.

Randomized pilot trial for the efficacy of the MMF07 foot massager and heat therapy for restless legs syndrome

Background

Restless Legs Syndrome (RLS) is a sensorimotor condition with a wide range of severity. Symptoms negatively affect sleep and quality of life. Pharmacologic options are not universally effective and side effects are common. Objective data regarding non-pharmacologic treatment is limited. The study objective was to evaluate the efficacy of the MMF07 foot massager and heat therapy on the severity of RLS symptoms.

Methods

In this pilot randomized controlled trial, twenty-eight patients with diagnosed, bothersome RLS were randomized to four treatment arms: no active intervention (n = 7), foot massager (n = 8), heat therapy (n = 6), and foot massager plus heat therapy (n = 7). Participants completed the RLS Severity Scale, RLS Quality of Life questionnaire, and the Medical Outcomes Study Sleep scale at the baseline visit and at the 4-week follow up visit.

Results

Four weeks post randomization, participants in the massager group had significant improvement in the RLS severity score (average difference: -9.0, 95% CI: -16.3, -1.7, p = 0.017) and sleep scale (average difference: -22.0, 95% CI: -36.5, -7.5, p = 0.005) compared to the no intervention group. The heat alone group had a significant improvement in the sleep scale compared to the no-intervention group (average difference: -17.4, 95% CI: -32.5, -2.3, p = 0.026). Quality of life improved in the massage only group compared to control (average difference 25.3, 95% CI: -2.4, 53.0, p = 0.072).

Conclusions

Results suggest that the MMF07 foot massage device and heat therapy may be feasible and effective treatment options to improve RSL symptoms.