The most prevalent form of headache found in the present study was migraine, although women with headache from excessive use of medication also had the initial diagnosis of migraine. In a study conducted in six Latin American countries, migraine was the most prevalent form of headache, with Brazil in second place among the countries studied. It is observed that migraine generally affects those aged from 30 to 50 years , which was evident in our study also. There was a slight variation in patient ages in the groups. Few studies correlate the prognosis and natural history of migraine with age. However, this difference in the randomized groups did not affect the results of the researches .
When comparing the basal index of pain between the two selected groups, it was considered important that no statistical difference was present, allowing the possible conclusion that the patients started treatment with the same intensity of pain. The same instrument was used to determine the index of pain after treatment, showing the analgesic effect of acupuncture in the true acupuncture group compared with the sham acupuncture group. Furthermore, both the number of crises and the number of analgesics used during the first and second months of treatment were significantly lower in the true acupuncture group.
A review from the Cochrane Institute showed that acupuncture in migraine is equally effective as or even more effective than preventive medication and has fewer adverse effects . In TTH, acupuncture did not seem superior to physiotherapy, massages, or exercises; however, new studies were suggested to rectify the methodological flaws. The authors conclude that acupuncture could be a valuable nonpharmacological tool in patients with episodic TTHs or frequent chronic headache crises .
A prospective, randomized, controlled study with 401 patients with complaints of chronic headache (mostly migraine) in the primary care network in England and Wales compared acupuncture (12 sessions in three months) with medication and routine care. The acupuncture group had a steeper improvement in symptom scale (acupuncture 34%/control 16%), 22 fewer days of headache, used 15% less medication, and had 25% less visits to the doctor .
In accordance with the study mentioned above, all participants in the present research used medications recognized as standard treatment, i.e., preventive medications such as topiramate, nortriptyline, and propranolol and abortive medications such as sumatriptans and nonsteroidal antiinflammatory drugs. They, then, underwent acupuncture sessions as an auxiliary treatment, which had improvements in the evaluative variables of pain.
The studies on the effects of acupuncture are frequently limited by serious methodological difficulties. To date, a universally accepted model of sham acupuncture (placebo) has not been established. By analyzing the placebo and the control model of 47 randomized controlled trials of acupuncture treatment for pain and other conditions, a group of authors observed that two studies used superficial needling of acupuncture points, four used acupuncture points that would not be suitable for the condition studied, 27 used needling out of the acupuncture points, five used placebo needles, and nine studies used pseudo-interventions, such as laser acupuncture with the equipment turned off .
The models that are used as placebo, such as superficial needling in acupuncture points, acupuncture points that would not be suitable for the condition studied, and needling out of the acupuncture points are not considered ideal as placebo method, as they are also methods that stimulate the peripheral nerve endings, causing analgesic effects, although in smaller proportion than true acupuncture .
The placebo used in this study was noninvasive masking, that is, there was no contact of the needle to the skin of patients. Therefore there was no stimulation of peripheral nerve endings. Besides, a prerequisite for reproducibility would be a uniform training of acupuncturists participating in a study . This problem was overcome in the study because only one acupuncturist performed the treatment.
The gold standard method for determining the effectiveness of therapies is the detection of a significant difference between a pharmacologically active agent or a procedure and an inert placebo assessed in a randomized clinical trial . The present study, using both an inert placebo and a randomized design, demonstrated a statistically significant difference in the effectiveness of true acupuncture. This placebo method which involves noninvasive masking can be promising. In addition, one of the inclusion criteria used was that patients had never undergone acupuncture sessions before, which contributed to their blinding.
Chronic pain has negative consequences for general health and hence to quality of life, causing physical and psychological discomforts [18, 19].
A study conducted to assess the quality of life of patients with chronic pain, including migraine, who underwent treatment with acupuncture, showed the highest score in the general state of health domain, followed by the mental health and functional capacity domains. The lowest scores were obtained in the physical limitation, pain, and emotional limitation domains .
Another study that assessed the effect of acupuncture on the quality of life in patients with migraine without aura compared acupuncture with flunarizine and demonstrated that although both groups had improvements in all aspects, the group that used only acupuncture had significantly superior improvements to the group that used only medication in functional capacity, physical limitations, and pain domains .
We can observe in the results of the present research that after treatment, there was statistically significant improvement in the true acupuncture group in almost all the domains. The exceptions were in the emotional limitation and mental health domains, since these already had good basal scores.
In the Quality of Life Questionnaire, the body pain domain assesses the severity of the pain felt by the patient, limiting the usual functioning at home and at work . In this domain, improvement was demonstrated in both groups because the patients in the sham acupuncture group, although receiving placebo, underwent drug treatment just as those in the true acupuncture group. These results also contributed to the significant improvement in question 2, in which health is assessed in comparison to 1 year back.
Some limitations to this study should be considered including the small sample size being directed to a specific type of headache and not using the same preventive medication for pain. However, it is worth pointing out that it was conducted with the following methodological criteria which may give credibility to the results; it was randomized, the assessor (pain specialist) was blinded, one acupuncturist conducted all the sessions, and a promising placebo method was used.
Another limitation of our study related to the size for comparison of the average number of analgesics used during the first and second month of treatment (Table 3). However, significant differences in intragroup and intergroup comparisons were observed, indicating that the sample under study had the power to detect statistical significance.