DOCTORS' BLOG

Archive for February, 2010

Chronic daily headache (CDH) is a common problem, affecting approximately 3 to 4% of the population. CDH poses a significant therapeutic challenge to both physician and patient.

For those with moderate or severe CDH, preventive medications are often utilized in an effort to limit analgesics and decrease headache frequency and/or severity. The primary first-line preventives include antidepressants (primarily selective serotonin reuptake inhibitors and tricyclics) and anticonvulsants. Antidepressants have been an attractive choice in those with comorbid depression and anxiety. Tricyclic antidepressants have been known to have enhanced efficacy of SSRI’s, but are not as well tolerated. The anticonvulsants sodium valproate and topiramate have emerged as effective drugs for use in CDH.

In our current study, only 46% of the patients obtained significant long-term relief from a preventive medication. While there are a variety of preventive medications available including, but not limited to, sodium valproate, antidepressants, beta blockers, muscle relaxants, NSAIDs, gabapentin and topiramate, many patients cannot tolerate these medications or find that efficacy is lacking. Among those who do benefit, side effects such as weight gain and fatigue may, over time, cause them to discontinue the medication. The patient may also experience a decline in efficacy over time. Most of the new breakthrough medications have been in the abortive category—particularly the triptans.  Currently there is a lack of new or novel headache preventives.

Many medications have been utilized in an effort to decrease severity and/or frequency of CDH. Short-term (less than six month) studies often demonstrate success at preventing CDH. However, the long-term success of these medications for CDH has not been demonstrated. In fact, while antidepressants and anticonvulsants demonstrated reasonable long-term efficiency, the majority of patients do not obtain adequate long-term relief from CDH preventive medications.

There is a lack of agreement between the results of short-term studies and those which we observed anecdotally regarding long-term success of daily preventive medications.  We need longer-term studies, at least nine to twelve months in length, in order to adequately evaluate the daily preventives. In addition, we need a new approach to more effective daily preventive medications for chronic daily headache.

Outpatient Treatments for RCM

New Technologies and Pharmacotherapies

There are a number of therapeutic options for RCM (Refractory Chronic Migraine), including inpatient treatment. New approaches such as transcranial brain stimulation (TMS), are in various stages of development and will come along. TMS has the potential to alleviate RCM without side effects. There is currently one newer type of TMS machine in use in the US, The Neurostar machine. It is FDA-indicated for the treatment of depression. There is another type of TMS unit in development by the company Neuralieve, which will be primarily used as a migraine abortive. It has the advantage of being readily available in a patient’s home.

Occipital nerve stimulation has been beneficial for a small number of RCM patients. Techniques of implantation have improved but the technical challenges need to be overcome; the leads tend to migrate away from the occipital nerve, for example. Other implantable stimulators are being studied, such as the Bion microstimulator and the Precision Implantable Stimulator for Migraine. It is too early to know what, if any, role these will play.

In pharmacology, there are a number of emerging compounds that may eventually come to market. These include newer abortives, such as 5-HT   drugs.  These work on the 5-HT F receptor, while the current triptans target B and D. CGRP antagonists, such as olcagepant and telcagepant, may be very useful. Gap junction blockers at the neural-glial level are being assessed. Finally, glutamate receptor antagonists are currently in Phase III trials.

Migraine with and without aura is associated with an increased risk of both cardiovascular disease (CVD) and risk factors for CVD, according to an analysis of data from the American Migraine Prevalence and Prevention study.

In an accompanying editorial, Dr. Hans-Christoph Diener with the University Duisburg-Essen and Dr. Judith Harrer with the Department of Neurology at Caritas Klinik St.Theresia in Germany agreed with the study authors that the analysis was limited by certain factors, including a lack of in-person assessments and an inability to control for certain risk factors.

Regardless they remarked that certain conclusions could be drawn from the findings. In particular, they noted, these data suggest that the absolute risk of vascular events in patients with migraine is small, and that such patients should be counseled with absolute rates rather than increases in relative risk.

In addition, they wrote, the increased prevalence of CVD risk factors among the patients with migraine in this study undermines the perception that patients with migraine lead relatively healthy lifestyles, while the data as a whole suggest that vascular risk factors in these patients should be assessed and appropriately treated.