Entry Demographics and Pharmacological Treatment of Migraine Patients Referred to a Tertiary Care Pain Clinic

Abstract

The aim was to examine pharmacological treatment of migraine patients admitted to a tertiary care pain clinic. A retrospective review of 100 consecutive migraine patients admitted to The Wasser Pain Management Centre was conducted. Patients included met the 2nd Edition of the International Classification of Headache Disorders criteria for diagnosis of migraine. Data were collected with regard to nicotine and alcohol consumption, family history of migraine headaches, other pain diagnoses and pharmacological treatment. Twenty-two per cent of these patients were male as opposed to 78% female. The mean age of patients admitted for migraine was 43.4 years. Of the patients admitted, 48% had tried at least one triptan in the past and only 31% were actively using triptan(s). The most commonly used triptan in the past had been sumatriptan, whereas the most common triptan used on admission was rizatriptan. Opiate use was much more prevalent; 72% of admitted patients were using an opiate and 27% used multiple opiates. A significant number of patients had not yet been tried on a triptan despite meeting the diagnostic criteria for migraine and having significant disability. More education of the general medical community may be beneficial in implementing a stratified care approach to migraine management.

Introduction

Headache is the most common reason for referral to neurologists (1). However, migraine headaches are the most common referral to specialized pain/headache clinics (2,3). Migraines are very common, with a lifetime prevalence of 7.8% in men and 24.9% in women (4). However, many patients with migraine do not seek medical therapy (5). In fact, a significant number of patients with migraine are never diagnosed (6). Of those which do seek medical attention, many are significantly disabled by their migraines, requiring time off employment (7). Historically, two approaches have been used in migraine treatment: step care and stratified care. Step care management involves escalating medication after first-line treatments fail (8). In stratified care, initial treatment is based on measurement of the severity of migraine and disability (8). This stratification can be performed by using the Migraine Disability Assessment Scale (MIDAS) (grades of II, III and IV, with IV being the most disabling) (9,10). Many primary care physicians commonly use step care in approaching headache patients (11). However, the Disability in Strategies of Care study has demonstrated that stratified care is more effective than step care as measured by headache response and disability time (8).

The objective of this study was to examine the demographics and pharmacological treatment of patients referred to a tertiary pain clinic. Many of these patients are at the severe end of the migraine spectrum with disabilities (12). This often results in significant costs to the healthcare system and economy (13), a burden that may be avoided if treatment is more effectively optimized in a primary care setting.

Methods

A retrospective review was conducted of 100 migraine patients admitted to the Wasser Pain Management Centre between June 2006 and July 2007. Patients included met the 2nd Edition of the International Classification of Headache Disorders (ICHD-II) criteria for diagnosis of migraine (14). Approval was obtained from the Ethics Committee at Mount Sinai Hospital (Toronto, Ontario, Canada). The vast majority of patients were referred from family physicians. Data were collected with regard to nicotine and alcohol consumption, family history of migraine headaches, other pain diagnoses and pharmacological treatment. All data were stripped of specific patient identifiers. Patients diagnosed with analgesic-overuse headaches were excluded.

Results

Of the patients meeting the ICHD-II criteria for migraine, 22% were male as opposed to 78% female. The mean age of patients admitted for migraine was 43.4 years. Figure 1 demonstrates the age distribution in the study. Eighty-six per cent scored 0/4 on the CAGE questionnaire, compared with 8% having a score of 3–4/4 (15). The majority of patients (62%) reported no history of tobacco use. However, 17% were active smokers. A positive family history was noted in 61% of all patients admitted with migraine.

Figure 1.

Age distribution of patients admitted for migraine.

In addition to migraines, a significant number of patients also had comorbid pain diagnoses. Fibromyalgia was the most common associated condition, seen in 17% of patients (Fig. 2). Figure 2 demonstrates the distribution of associated pain diagnoses.

Figure 2.

Distribution of pain diagnoses of patients admitted for migraine.

Pharmacological therapy most commonly used for prevention of migraine included antiepileptics, β-blockers and tricyclic antidepressants (TCA) (Table 1). Topiramate was the most commonly used antiepileptic used in the past or at the time of admission. Similarly, propranolol was the most commonly used β-blocker and amitriptyline the most common TCA. Other medications that were the most commonly used in the past or on admission included venlafaxine, seen in 21% of patients (Table 1).

Table 1.

Pharmacological therapy used for prevention of migraines prior to and on admission to pain clinic (n = 100)

Pharmacological agent	Number of patients using on admission (n)	Number of patients that have used in past (n)
Antiepileptics
Topiramate	12	8
Phenytoin	1	0
Carbamazepine	2	3
Oxcarbamazepine	0	1
Gabapentin	8	7
Pregabalin	1	1
Divalproex	4	1
Lamictal	0	1
β-blockers
Propranolol	4	10
Nadolol	1	1
Atenolol	1	1
Tricyclic antidepressants
Amitriptyline	12	11
Nortriptyline	2	4
Trazadone	3	0
Others
Venlafaxine	18	3
Sandomigran	2	5
Lithium	1	1
Verapamil	3	6
Baclofen	1	0
Botox	0	6

Pharmacological therapy used for migraine included: serotonin receptor agonists (triptans), opiates, ergot alkaloids, non-steroidal anti-inflammatory drugs (NSAIDs), paracetamol and barbiturates (Table 2). Of the patients admitted, 48% had tried at least one triptan in the past and only 31% were actively using triptan(s). The most commonly used triptan in the past had been sumatriptan, whereas the most common triptan used on admission was rizatriptan. Table 2 demonstrates the distribution of triptans used on admission or in the past.

Table 2.

Pharmacological therapy used for treatment of migraines prior to and on admission to pain clinic (n = 100)

Pharmacological agent	Number of patients using on admission (n)	Number of patients that have used in past (n)
Serotonin receptor agonists
Almotriptan	2	0
Eletriptan	1	0
Naratriptan	4	7
Rizatriptan	12	5
Sumatriptan	7	18
Zolmitriptan	5	13
Non-steroidal anti-inflammatory drugs
Aspirin	6	1
Celecoxib	1	4
Diclofenac	5	0
Ibuprofen	19	3
Indomethacin	1	1
Ketorolac	2	5
Meloxicam	2	1
Naproxen	8	6
Rofecoxib	6	3
Opioids
Oxycodone	29	13
Codeine	34	7
Fentanyl	7	5
Butorphanol	2	2
Hydromorphone	3	5
Mepiridine	7	3
Methadone	1	1
Morphine IR	6	6
Morphine SR	3	0
Propoxyphene	1	1
Pentazocine	1	2
Others
Butalbital	10	8
Ergotamine Tartrate	0	7
Paracetamol	11	1
Paracetamol/codeine	31	6

Opiate use was much more prevalent. Seventy-two per cent of admitted patients were using an opiate and 27% multiple opiates. The most frequently used opiate on admission was codeine in 34% of patients, followed by oxycodone used by 29%. Opiate use was followed by NSAIDs, which were actively used by 50% of patients admitted (Table 2).

Discussion

Of the 100 migraine patients referred to a tertiary care pain clinic, the vast majority had significant disability (i.e. severe migraine spectrum, MIDAS grades 3 or 4). A significant number of patients had not yet been tried on a triptan despite meeting the diagnostic criteria for migraine on admission. Despite the fact many of these patients were disabled with severe migraine, opiates and NSAIDs were more commonly prescribed in the primary care setting. It may be postulated that a step care approach by primary care physicians involves using opiates and NSAIDs as first-line treatments before triptans (16–18). It has been demonstrated that in patients stratified with severe migraines, management with triptans has been most effective in decreasing headache and disability (8).

This study population is not a typical cross-section of patients who present with migraine in a primary care setting. Of those migraine patients admitted in this study, a significant proportion had comorbid pain diagnoses, the most common being fibromyalgia. Twenty per cent of patients had comorbid cervical or lumbar-related pain issues. Opiates and NSAIDs may have also been used to treat these conditions in addition to migraine.

It is unclear how these comorbidities may have influenced primary care migraine management. It is certainly plausible that multiple comorbid pain complaints may have influenced clinicians and detracted from migraine-specific treatment. Furthermore, it would be interesting to compare triptan contraindications, such as rates of atherosclerosis and hypertension, in the primary care setting vs. our study population. Finally, our review was limited in that alteration of pharmacotherapy, following consultation at our pain centre, was not examined. This could easily be investigated in a future prospective study.

Conclusions

A significant number of patients had not yet been tried on a triptan despite meeting the diagnostic criteria for migraine and having significant disability. The vast majority of patients admitted have severe migraines resulting in significant healthcare and economic costs (13,19). A stratified approach may involve using analgesics/NSAIDs in milder cases and triptan use in more severe cases. This has been demonstrated to be effective in decreasing headache and disability (8). More education of the general medical community may be beneficial in implementing a stratified care approach to migraine management.