Physicians have noted the potential for dizziness in migraine patients since the 19th century. And yet the 21st century has so far failed to bring any unifying definition to a symptom that is frustratingly diffuse in its intensity and frequency and unclear in its origins.
The market has seen no wonder drugs, and most medications tailored to stopping migraine headaches, like triptans, do not address the primary manifestation of migraine-related dizziness, commonly known as migraine-associated vertigo. Despite the continued absence of rigorous clinical criteria or gold standards of care, however, otolaryngologists are achieving considerable success in treating migraine-associated vertigo, using a more ad hoc strategy that is based on their own experience, anecdotal evidence and therapeutic trial and error.
Eliminating potential triggers, closely monitoring diets and regulating sleep patterns have all proven effective as initial interventions. For more stubborn cases, diagnosis may hinge on how well patients respond to a variety of medications repurposed for migraine-associated symptoms. Using drugs approved for everything from Alzheimer’s disease and epilepsy to high blood pressure and depression, otolaryngologists are finding they can provide relief for a clear majority of their patients.
“Roughly 80 percent of the people that I’ve had in my practice respond to the first drug that I give them, and then the other 20 percent, they struggle,” said Joel Goebel, MD, professor and vice chair of the department of otolaryngology-head and neck surgery at Washington University School of Medicine in St. Louis, Mo.
In the U.S., rough estimates suggest that 18 percent of women and 6 percent of men between the ages of 12 and 80 experience a migraine-type disorder, with rates peaking at about 25 percent among 35-year-old women. Of these patients, one-fourth to one-third may experience episodes of dizziness, chiefly vertigo. Episodes may last seconds or days, and symptoms may appear before or during a headache, ranging from occasional dizziness to severe, progressive brain-damaging disorders.
As otolaryngologists emphasize, however, migraine patients often experience vertigo during headache-free periods. “Some people, for example, will have a pattern where they have headaches, and then for a few years they’ll just have vertigo spells, and then they’ll go back to having headaches again,” said Carol Foster, MD, director of the Balance Laboratory and associate professor of otolaryngology at the University of Colorado, Denver. “So the vertigo is sort of the migraine.”
Because migraine-associated vertigo is widely viewed as a diagnosis of exclusion, otolaryngologists may order MRIs, audiograms and vestibular testing to rule out causes such as a tumor, vestibular or viral neuritis or Ménière’s disease.
“If I have a patient with vertigo and we’re not getting control easily, I may treat for migraine to see if it works.”
—Carol Foster, MD
Overdiagnosis?
The lingering uncertainty over diagnosis and treatment has led some critics to openly question whether the condition is being oversold. Neurotologists at the University of British Columbia recently published a commentary in the journal Headache in which they labeled migraine-associated vertigo as “neither clinically nor biologically plausible as a migraine variant” (2010;50(8):1362-1365).
Among otolaryngologists, however, that sentiment appears to be a minority viewpoint. “I think the diagnosis of migraine-associated vertigo is more widely received now than it had been previously,” said Joe Walter Kutz, MD, assistant professor of otolaryngology at the University of Texas Southwestern Medical Center in Dallas. “It’s still a difficult diagnosis to make, and there is still controversy.”
The International Headache Society (IHS) does not yet recognize migraine-associated vertigo as a distinct entity, although several movements are afoot to establish more formal diagnostic criteria, including one led by Hannelore Neuhauser, MD, MPH, of the department of epidemiology and health reporting at the Robert Koch Institute in Berlin.
With a lack of agreed-upon guidelines, other efforts are underway to compile data that might better delineate the condition. One example is the CHEER Network (Creating Healthcare Excellence through Education and Research), which is building a national infrastructure for practice-based clinical research focused on hearing and balance disorders. According to network co-principal investigator Debara Tucci, MD, professor of otolaryngology-head and neck surgery at Duke University Medical Center in Durham, N.C., a team led by investigators at the University of California-Los Angeles and Mayo Clinic in Rochester, Minn., is seeking funding for a proposal to further define migraine-associated vertigo. The epidemiological research, she said, would tap into the CHEER Network.
Evidence that clinicians are expanding on the traditional view of what constitutes a migraine comes from a recent Otology & Neurotology study of 26 patients who had experienced at least three months of otalgia symptoms of unclear origin (2011;32(2):322-325). Only 17 of the patients fit the IHS criteria for a migraine. Nevertheless, 24 responded well to migraine preventive and abortive therapies, based on a scored comparison of pre- and post-treatment symptom severity, frequency and duration. Dr. Foster agreed that restricting treatment to those with classic IHS migraine could leave out a host of patients who might otherwise benefit. “The reality is that if I have a patient with vertigo, especially a damaging vertigo, and we’re not getting control easily, I may treat for migraine to see if it works, because it’s so common,” she said.
Lifestyle and Diet
Therapy usually means first exploring non-pharmacological approaches. “Really you go back to the migraine treatment: You try to address lifestyle changes, avoiding stress, getting a good night’s sleep, trying to avoid too much caffeine or any trigger,” said Maroun Semaan, MD, associate director of the otology, neurotology and balance disorders section at University Hospitals of Case Medical Center in Cleveland, Ohio. Yoga and psychotherapy sometimes help, he added.
“Migrainers are hypersensitive to all sensory stimuli and that includes side effects of medications,” Dr. Foster said. “So you end up with a group [for whom] there are medicines we can use to help, but they won’t take them. So I usually start with a non-medicine approach, and then only if that fails do I go on to using a migraine prophylactic.”
Several otolaryngologists said patients can help themselves by taking vitamin supplements, notably riboflavin and magnesium, the latter of which may reduce a type of vasospasm thought to be linked to migraines. Dr. Foster said she reviews several pages full of possible triggers with patients. Cheese, yogurt and monosodium glutamate often play big roles. Other otolaryngologists cite eggs, wine and nicotine.
Regulating sleep cycles may also do wonders. Dr. Foster said she now regularly questions her migraine patients about sleep apnea, after noticing an unusually strong connection between the two. Similarly, she estimated that about 25 percent of her Ménière’s disease patients have sleep apnea. “It turns out that sleep apnea presents as an early morning headache, often, in a patient who snores,” she said. “And in people who have any kind of migraine tendency, it presents as a severe exacerbation of migraine, which can include the vertigo part.”
If those patients can tolerate wearing a CPAP (continuous positive airway pressure) device at night, she has discovered, their symptoms often resolve.
Modifying a patient’s diet may be especially important for children or pregnant women who cannot take many of the available medications. Among children with migraines, Dr. Goebel has gained the upper hand over previously out-of-control symptoms by limiting patients’ intake of caffeine and sugar, especially by curtailing caffeinated sodas that might produce wild swings in sugar levels. He experienced similar success by advising patients to limit their intake of cheese on pizza and other foods.
“The problem with Inderal as a beta blocker is that if you give it to a younger person, not only does it lower their blood pressure, but it lowers their exercise tolerance.”
—Joel Goebel, MD
Medication
When medication becomes necessary, otolaryngologists often have their favorite standbys as first-line treatments. Experts, however, said several considerations are warranted regardless of the regimen. Dr. Foster said she tailors prophylactic medications to the severity and full suite of a patient’s symptoms, as well as the side-effect profiles of candidate drugs. Dr. Semaan recommended starting the medication slowly and increasing the amount based on the patient’s tolerance, then staying with the medication for at least six months before tapering back down. For more severe cases of vertigo, especially those that don’t respond to a first or second-line drug, otolaryngologists said involving a neurologist is always a good idea.
For a first or second-line therapy, common drugs of choice include verapamil (Calan) and the tricyclic antidepressant nortriptyline (Pamelor). For verapamil, “We use it in a very low dosage, below levels that we would use for blood pressure control,” said Aaron Benson, MD, clinical adjunct professor of otolaryngology head and neck surgery at the University of Michigan and Michigan State University. “I find that to be very effective in my patients and it has the lowest side effect profile of the medications that I can normally offer to patients,” said Dr. Benson, also medical director of the Ohio Hearing and Balance Institute at St. Luke’s Hospital in Maumee.
Dr. Foster agreed, noting that verapamil is a good choice for patients with hypertension or arrhythmias. How the drug works is less clear, especially in light of the uncertain etiology of migraines. One hypothesis suggests symptoms may be related to a vasospasm of the blood supply to the posterior fossa. Another posited that the condition results from a disruption of calcium ion channels. Either way, Dr. Benson said calcium channel blockers make sense as a first-line therapy. “A calcium channel blocker relaxes vessels so it would work if it’s vasospasm, and if it’s a calcium ion channel problem, well, it’s a calcium channel blocker,” he said. “I find that to be an extremely effective medication.”
Dr. Goebel often starts with the relatively inexpensive nortriptyline, which he prefers over its chemical cousin amitriptyline (Elavil) because it is less sedating and patients aren’t as likely to gain weight. Dr. Foster noted that amitriptyline’s sedative effect can be a plus for patients with poor sleep patterns, thereby also removing lack of sleep as a potential migraine trigger. Other side effects can include dry eyes and a dry mouth, and both drugs are usually contraindicated for pregnant women.
The potential mechanism for action by tricyclic antidepressants in addressing migraine is poorly understood, though some researchers suggest that regulation of the serotonin neurotransmitter may play a role. Experts also note that antidepressants have been widely used for pain control.
New Options
Among the few promising new drugs, Dr. Foster pointed to Namenda (memantine), normally used to treat Alzheimer’s disease. The drug seems to work best in cases with prominent aura, she said, when the inner ear may be damaged by low blood flow, by blocking the NMDA [N-methyl-D-aspartate] receptor calcium channel. That channel is involved in excitotoxicity, or the death of nerve cells from excessive stimulation, a pathway that Dr. Foster has been exploring as the mechanism for severe attacks. “If you can block excitotoxicity, you can block the damage,” she said. “So for people with progressive damaging disorders who have migraine, blocking that kind of damage then prevents the disorder from progressing.”
Patients with uncontrolled migraine-associated vertigo who had failed other drug treatments found relief with the drug, Dr. Foster said. “But this is really early, so we don’t know yet what the difficulties that we’re going to encounter with the drug are.”
Specialists agreed that other potent drugs like topiramate (Topamax), used to treat seizures in epilepsy patients, should likewise be reserved as a third-line option if other regimens fail. Dr. Goebel cautioned that he’s encountered cognitive problems among some patients on the drug. “You get some word-finding problems, not being able to exactly come up with the word you want to use,” he said.
Similarly, beta blockers like propranolol (Inderal) may be effective but can have a significant downside. “The problem with Inderal as a beta blocker is that if you give it to a younger person, not only does it lower their blood pressure, but it lowers their exercise tolerance,” Dr. Goebel said. Dr. Foster also uses propranolol sparingly, but noted that it can be a good choice for migraine patients with tremor or high blood pressure.
A similarly intense medication like the anti-epileptic and altitude sickness drug acetazolamide (Diamox) may likewise help in more severe cases, Dr. Foster said, such as vertigo with damaging hearing loss. Diamox, Inderal and the occasionally prescribed anti-seizure medication lamotrigine (Lamictal) may not stop headaches, though, potentially requiring such patients to take more than one drug.
Experts have pointed to some limited success with the depression and generalized anxiety disorder drug escitalopram (Lexapro), although the medication is prescribed primarily by neurologists. Another small randomized clinical trial pointed to zolmitriptan (Zomig) as a somewhat beneficial abortive treatment, a rarity among triptans. And an observational study found marginal improvement with the blood pressure medication metoprolol (Lopressor, Toprol) (J Neurol. 2009 256(5):711-716).
The take-away lesson, otolaryngologists say, is that a suite of symptoms still in search of clear categorization may nevertheless respond to a carefully chosen, individually tailored treatment regimen that stops the spinning world of vertigo patients.