Cerebrovascular response in migraineurs during prophylactic treatment with acupuncture: a randomized controlled trial.
The study objective was to evaluate the effect of acupuncture on cerebrovascular response in migraineurs by transcranial Doppler ultrasound. This study was a randomized, quasi double-blinded, placebo-controlled study. Thirty-five (35) migraineurs were diagnosed according to the International Headache Society criteria. The stimulus paradigm was performed in 18 verum and 17 placebo acupuncture patients. Participants were treated with acupuncture according to Traditional Chinese Medicine recommendations. All patients received one session of acupuncture each week for 8 weeks. To evaluate the clinical effect of acupuncture treatment, headache frequency and intensity was monitored by a headache diary. Cerebral blood flow velocity data were analyzed with a validated technique based on automated stimulus-related averaging. Vasotonus was determined by systolic and mean flow velocities and pulsality index in right and left middle cerebral arteries during rest. Cerebrovascular response was evaluated by detecting the cerebrovascular Valsalva ratio by maximum end-diastolic flow velocity acceleration during the straining phase of a Valsalva maneuver. Additionally, the centroperipheral Valsalva ratio was determined by the quotient of the cerebrovascular ratio to the corresponding blood pressure acceleration. Pre-/post-acupuncture treatment comparisons between verum- and placebo- acupuncture groups demonstrated a significant decrease of days with migraine headache in the verum group (-52.5%; p<0.001), whereas placebo-acupuncture patients profited to a smaller extent and the duration of headache attack (hours/month) did not decrease significantly. Pretreatment recordings showed increased vasotonus and exaggerated cerebrovascular response in migraineurs. Pre-/post-treatment comparisons demonstrated no significant differences in vasotonus between groups, while cerebrovascular response patterns to Valsalva stimulus were significantly (p<0.001) diminished in verum-acupuncture patients, but not in the placebo group. The findings indicate that prophylactic treatment of migraineurs by standardized acupuncture might positively influence the dysfunction of the cerebrovascular response to autonomic stimuli, but not the cerebral vasotonus during rest.