Dopamine Transporter Density Profiles in Patients With Periodic Limb Movements
Condition: Periodic Limb Movements in Sleep
Study type: Interventional

Summary: 
      Restless legs syndrome and periodic limb movement (PLM)are sleep-related movement disorders
      and studies have shown changes in striatal dopaminergic activity in patients with these
      disorders. Physical exercise has been shown to improve the symptoms of restless legs syndrome
      and PLM, as has treatment with dopamine agonists. However, the mechanism by which physical
      exercise acts as a non-pharmacological treatment in improving symptoms of restless legs
      syndrome and PLM remains unknown. The investigators evaluated dopamine transporter density
      profiles in 16 sedentary patients (control and experimental - with PLM, groups) and the
      influence of acute physical exercise on its concentration after a maximal exercise test. Each
      patient underwent baseline polysomnography to evaluate sleep patterns and PLM index values.
      After obtaining the polysomnography baseline, the single photon emission computer tomography
      baseline was determined. Subsequently, the volunteers performed a maximal exercise test in
      the morning, followed by a single photon emission computer tomography two hours later and
      polysomnography that night, to assess the effect of acute physical exercise on dopamine
      transporter and sleep patterns. The results showed significant lower dopamine transporter
      baseline densities in the striatum region for the experimental group. The results also showed
      a significant reduction in the periodic leg movement rate in the experimental group and a
      significant increased percentage of stage-1 non-REM sleep in both groups after maximal
      exercise test. Significant differences between the groups were only observed for Stage 2
      sleep and slow wave sleep. Our results show that patients with PLM had a lower dopamine
      transporter density in the left putamen region compared to the control group and an acute
      physical exercise (maximal exercise test) did not alter this profile, providing evidence that
      this improvement is the result of chronic physical exercise.
    

Detailed description: 
      Experimental Design Each volunteer (in both control and experimental groups) underwent
      Polysomnography (PSG) adaptation. After one week, a baseline cerebral SPECT was performed
      (1-3pm) and a baseline PSG was performed that night to evaluate the sleep pattern and the PLM
      index. Subsequently (after one week), each subject underwent a maximal exercise test (MET) in
      the morning (11am to 1pm) after which SPECT examination was performed in the afternoon (1-3
      pm). A PSG was then performed that night to evaluate the effect of acute exercise on DAT
      density and sleep pattern (Figure 1).
    

Intervention name(s): Aerobic Physical Exercise; Aerobic Physical Exercise
Intervention type(s): Behavioral; Behavioral
Intervention description(s): All individuals were submitted to physical exercise reaching maximum effort; All individuals were submitted to physical exercise reaching maximum effort
Other intervention name(s): Acute Physical Exercise: Maximal Exercise Test; Acute Physical Exercise: Maximal Exercise Test
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Health Services Research
Keywords: PLM; dopamine; physical exercise