Abstract
Objective
The aim of this study was to evaluate the efficacy of a therapeutic pathway for vestibular migraine (VM) and complex dizziness of undetermined etiology (CDUE) with caffeine cessation and pharmacotherapy.
Study Design
This study is a retrospective chart review.
Intervention(s)
Patients were recommended to stop intake of caffeine and other putative migraine-triggering agents. Pharmacotherapy was initiated with nortriptyline or topiramate if symptoms persisted despite diet modification.
Main Outcome Measure
Self-reported dizziness is the main outcome measure.
Results
Vestibular migraine and CDUE were considered contributing factors to dizziness in 34 and 10, respectively, of 156 patients. Fourteen percent of patients reported improvement in symptoms upon caffeine cessation, whereas 46% of patients reported a reduction in dizziness after nortriptyline therapy ( P = .007). Topiramate reduced symptoms in 25% of patients. In total, 75% of VM patients and 56% of patients with CDUE received sufficient benefit from this therapeutic pathway to not progress to other treatments.
Conclusions
Vestibular migraine and CDUE can be treated effectively with a therapeutic pathway consisting of caffeine cessation followed by pharmacotherapy.
1
Introduction
A portion of patients presenting to dizziness clinics have symptoms that may be attributed to vestibular migraine (VM). Vestibular migraine, also known as migrainous vertigo and migraine-associated dizziness, is a migraine variant for which specific diagnostic criteria have been proposed . However, VM has not been officially recognized by the International Headache Society as a migraine variant . As a result, this lack of recognition may act as a contributing factor to a subset of patients with dizziness escaping categorization despite a thorough evaluation. In our practice, we describe another subset of patients as having “complex dizziness of unknown etiology” (CDUE)—those patients who do not have an underlying cause for their dizziness identified despite evaluation by both a neuro-otologist and neurologist specializing in dizziness. We have chosen to initially treat patients with CDUE equivalently to those with VM under the rationale that, because migraine is relatively common and VM is ill defined, it is possible that patients with CDUE may have a migraine variant as a cause of their dizziness.
Various treatments, including diet therapy, have been reported for VM . Some patients with migraine, be it VM or other variants, appear to have dietary or environmental triggers, and avoiding such triggers can result in relief of symptoms. Both the use of caffeine and caffeine withdrawal have been suggested to be triggers of migraine for some patients, yet caffeine is a component of over-the-counter migraine medications and has also been used in clinical trials as a therapy against migraines . In an effort to resolve the ambiguity currently in the literature regarding the role of caffeine in migraine and to identify an effective method to treat patients with VM and CDUE, the authors retrospectively reviewed the records of patients presenting to the clinic with the primary complaint of dizziness to evaluate the efficacy of a therapeutic pathway to VM and CDUE with long-term caffeine cessation as a first step and pharmacotherapy with nortriptyline or topiramate as the second step.
2
Materials and methods
In this retrospective study, the records of 156 consecutive patients seen at a tertiary combined dizziness clinic by a neurologist and a neurotologist from 2005 to 2009 were reviewed. The records of patients who had reported caffeine intake and caffeine cessation, had undergone treatment with topiramate or nortriptyline, or had been diagnosed with VM or CDUE were selected and examined in detail. All patients diagnosed with CDUE had undergone thorough evaluation, including assessment for vestibular, neurologic, autonomic, and cardiac dysfunction as an underlying cause of dizziness.
This study was initiated with the purpose of assessing the prevalence of VM and the average quantity of caffeine consumption in our combined dizziness clinic, as well as to evaluate the efficacy of caffeine cessation, treatment with nortriptyline, and treatment with topiramate in patients with VM and CDUE. The caffeine concentrations used in this study were acquired either from company Web sites or by direct inquiry from the company and rounded to the nearest multiple of 5. The values for these calculations are listed in Table 1 .
| Beverage | Volume (oz) | Caffeine (mg) |
|---|---|---|
| Generic brewed coffee | 12 | 200 |
| Decaffeinated generic coffee | 12 | 15 |
| Diet Coca Cola | 12 | 50 |
| Coca Cola Classic | 12 | 35 |
| Pepsi and Diet Pepsi | 12 | 40 |
| Dr Pepper and Diet Dr Pepper | 12 | 40 |
| Mountain Dew | 12 | 55 |
| Tea, brewed | 12 | 75 |
| Decaffeinated tea | Negligible |
Pharmacotherapy was initiated if patients continued to complain of dizziness symptoms after 4 to 6 weeks of caffeine cessation and diet modification. Nortriptyline was prescribed in an escalating fashion, starting with a dose of 25 mg nightly for 2 weeks, then escalating to 50 mg nightly for 2 weeks, and then finally escalating to 75 mg nightly. Patients were recommended to maintain the lower dose of 25 or 50 mg if they received sufficient benefit at that dose. Topiramate therapy was initiated at 25 mg twice daily and occasionally increased to 50 mg twice daily based on patient tolerance and preference. Drug selection was based on cost, side-effect profile, interactions with other patient medications, and familiarity of the prescribing physician with the medication. The Saint Louis University Institutional Review Board approved this study.
Statistical analysis was conducted using a 2-tailed Fisher exact test with the GraphPad QuickCalc online statistical tool: http://www.graphpad.com/quickcalcs/contingency1.cfm (accessed November 2010).
2
Materials and methods
In this retrospective study, the records of 156 consecutive patients seen at a tertiary combined dizziness clinic by a neurologist and a neurotologist from 2005 to 2009 were reviewed. The records of patients who had reported caffeine intake and caffeine cessation, had undergone treatment with topiramate or nortriptyline, or had been diagnosed with VM or CDUE were selected and examined in detail. All patients diagnosed with CDUE had undergone thorough evaluation, including assessment for vestibular, neurologic, autonomic, and cardiac dysfunction as an underlying cause of dizziness.
This study was initiated with the purpose of assessing the prevalence of VM and the average quantity of caffeine consumption in our combined dizziness clinic, as well as to evaluate the efficacy of caffeine cessation, treatment with nortriptyline, and treatment with topiramate in patients with VM and CDUE. The caffeine concentrations used in this study were acquired either from company Web sites or by direct inquiry from the company and rounded to the nearest multiple of 5. The values for these calculations are listed in Table 1 .
| Beverage | Volume (oz) | Caffeine (mg) |
|---|---|---|
| Generic brewed coffee | 12 | 200 |
| Decaffeinated generic coffee | 12 | 15 |
| Diet Coca Cola | 12 | 50 |
| Coca Cola Classic | 12 | 35 |
| Pepsi and Diet Pepsi | 12 | 40 |
| Dr Pepper and Diet Dr Pepper | 12 | 40 |
| Mountain Dew | 12 | 55 |
| Tea, brewed | 12 | 75 |
| Decaffeinated tea | Negligible |
Pharmacotherapy was initiated if patients continued to complain of dizziness symptoms after 4 to 6 weeks of caffeine cessation and diet modification. Nortriptyline was prescribed in an escalating fashion, starting with a dose of 25 mg nightly for 2 weeks, then escalating to 50 mg nightly for 2 weeks, and then finally escalating to 75 mg nightly. Patients were recommended to maintain the lower dose of 25 or 50 mg if they received sufficient benefit at that dose. Topiramate therapy was initiated at 25 mg twice daily and occasionally increased to 50 mg twice daily based on patient tolerance and preference. Drug selection was based on cost, side-effect profile, interactions with other patient medications, and familiarity of the prescribing physician with the medication. The Saint Louis University Institutional Review Board approved this study.
Statistical analysis was conducted using a 2-tailed Fisher exact test with the GraphPad QuickCalc online statistical tool: http://www.graphpad.com/quickcalcs/contingency1.cfm (accessed November 2010).
3
Results and analysis
Of the 156 charts reviewed, a total of 57 patients were suspected of VM, had reported caffeine intake and cessation results, or had been treated with topiramate or nortriptyline. This group ranged in age from 22 to 85 years, with a median age of 45 years, and was composed of 23% men and 77% women. For further analysis, the group was divided into patients with definite or probable VM and those with complex dizziness of unclear etiology (CDUE).
Based on vestibular testing and patient history, VM was considered a contributing factor to dizziness in 41 patients. The median age of the VM group was 44 years, ranged from 22 to 68 years, and was composed of 22% men and 78% women. These patients met the Neuhauser criteria for probable VM as described in Table 2 . Thus, probable VM had a prevalence of 26% at our tertiary dizziness clinic. The retrospective nature of this study precluded the authors to diagnose definite VM with certainty.
| Definite VM |
| • Episodic vestibular symptoms of at least moderate severity |
| • Current or previous history of migraine according to the 2004 criteria of the International Headache Society (IHS) |
| • One of the following migrainous symptoms during 2 or more attacks of vertigo: migrainous headache, photophobia, phonophobia, visual aura, or other aura |
| • Other causes ruled out by appropriate investigations |
| Probable VM |
| • Episodic vestibular symptoms of at least moderate severity |
| • One of the following: |
| (1) current or previous history of migraine according to the 2004 criteria of the HIS; |
| (2) migrainous symptoms during vestibular symptoms; |
| (3) migraine precipitants of vertigo in more than 50% of attacks: food triggers, sleep irregularities, or hormonal change; or |
| (4) response to migraine medications in more than 50% of attacks |
| • Other causes ruled out by appropriate investigations |
Sixteen patients were diagnosed with CDUE. Patients included in the CDUE group presented with an amalgamation of poorly defined symptoms defying easy categorization. Some patients reported symptoms consistent with episodic vertigo, some reported symptoms of disequilibrium without vertigo, others reported more vague sensations such fogginess or instability, and yet others reported a combination of the aforementioned symptoms. The age range in this group was 25 to 85 years, with median age of 58 years. The CDUE group was composed of 31% men and 69% women. Figs. 1 and 2 outline the therapeutic pathway used to treat patients with VM and CDUE, respectively.
