Article

OBJECTIVE: To determine whether repetitive and cumulative exposure to
low-frequency pulsed electromagnetic fields (PEMF) targeting painful feet can
reduce neuropathic pain (NP), influence sleep in symptomatic diabetic peripheral
neuropathy (DPN), and influence nerve regeneration.
DESIGN: Randomized,
double-blind, placebo-controlled parallel study. SETTING: Sixteen academic and
clinical sites in 13 states. PARTICIPANTS: Subjects (N=225) with DPN stage II or
III were randomly assigned to use identical devices generating PEMF or sham
(placebo) 2 h/d to feet for 3 months. INTERVENTIONS: Nerve conduction testing was
performed serially. MAIN OUTCOME MEASURES: Pain reduction scores using a visual
analog scale (VAS), the Neuropathy Pain Scale (NPS), and the Patient's Global
Impression of Change (PGIC). A subset of subjects underwent serial 3-mm punch
skin biopsies from 3 standard lower limb sites for epidermal nerve fiber density
(ENFD) quantification. RESULTS: Subjects (N=225) were randomized with a dropout
rate of 13.8%. There was a trend toward reductions in DPN symptoms on the PGIC,
favoring the PEMF group (44% vs 31%; P=.04). There were no significant
differences between PEMF and sham groups in the NP intensity on NPS or VAS.
Twenty-seven subjects completed serial biopsies. Twenty-nine percent of PEMF
subjects had an increase in distal leg ENFD of at least 0.5 SDs, while none did
in the sham group (P=.04). Increases in distal thigh ENFD were significantly
correlated with decreases in pain scores. CONCLUSIONS: PEMF at this dosimetry was
noneffective in reducing NP. However neurobiological effects on ENFD, PGIC and
reduced itching scores suggest future studies are indicated with higher dosimetry
(3000-5000 G), longer duration of exposure, and larger biopsy cohort.

Langue : ANGLAIS