The final study sample consisted of 284,719 patients with migraine who met all of the study inclusion criteria (Fig. 1). The average age of the patients was 40.1 ± 12.1 years and 79.1% were women; the average duration of follow-up was 31.3 ± 14.2 months (Table 1). Commonly observed baseline comorbid conditions (> 10%) were headache (28.5%), chronic pain (22.3%), hypertension (17.2%), depression (12.8%), chest pain (11.3%) and anxiety (11.0%). Patients had an average baseline DCI of 0.3 ± 0.8.
All-cause and migraine-related healthcare utilization by the study population during follow-up was analyzed. During follow-up, patients generally visited a physician’s office (99.5%; referred to as office visits henceforth) or the ER (49.5%) for any reason (Table 2). Patients also generally used the following healthcare services for migraine: office visits (83.3%), neurologist visits (38.5%), ER visits (11.6%) and neuroimaging scans (11.5%) (Table 2).
Office visits, both all-cause (20.0 ± 18.3 visits PPPM) and migraine-specific (2.7 ± 3.7 visits PPPM), were the most utilized healthcare resource among the study patients, followed by neurologist visits (1.0 ± 2.2 visits PPPM) and neuroimaging scans (0.1 ± 0.4 scans PPPM) (Table 2). The ER was not regularly utilized for any reason (1.4 ± 3.5 visits PPPM) or for migraine (0.2 ± 0.9 visits PPPM). In contrast, those with at least one migraine-related ER visit averaged a markedly higher number of visits (1.6 ± 2.1 visits PPPM). Following a migraine-specific ER visit, migraine-specific office (8.1%) and neurologist (3.9%) visits were not commonly observed. Of those who had a migraine-related office/neurologist visit after a migraine-related ER visit, less than half made an office (36.5%) or neurologist (30.2%) visit within 2 weeks; on average, these visits occurred > 100 days after a migraine-related ER visit (office visits 111.0 ± 206.2 days; neurologist visits 132.7 ± 236.9 days). The smallest category of observed healthcare utilization was IP admissions for any reason (20.4%) and for migraine (6.5%) (Table 2).
In general, patients used both acute and preventive therapies (54.6%) or only acute therapy (32.9%) (Table 1). More than half of the study patients used preventive medication (59.1%) and started treatment within 0.7 months (median) of their diagnosis. Most patients used their first preventive treatment for a median of 4.0 months before discontinuing treatment or switching to another treatment. Of note, the median time to discontinuation of the first preventive treatment was 5.4 months (Table 3).
Only one-half of those who started a first preventive treatment (48.5%) went onto a second preventive treatment, with 50% of the latter starting the second preventive treatment within 2.6 months of ending their first preventive treatment. Patients starting on a second preventive treatment stayed on that treatment for a median of 3.0 months, and 45.0% subsequently started a third preventive treatment. The median time from the end of the second preventive treatment to the start of the third preventive treatment was 2.9 months, and the median duration of the third preventive treatment was 2.7 months (Table 3). About one-half (48.8%) of patients who discontinued preventive therapy never started another preventive therapy during the median post-discontinuation follow-up time of 26.5 months. Among the discontinuers of preventive therapy, 77.6% started on an acute therapy (43.5% within 3 months of preventive therapy discontinuation; 68.4% within 1 year), 18.3% visited a neurologist and 6.2% had a migraine-specific ER visit in the post-discontinuation follow-up period (Table 3).
In general, all patients on acute medication used opioids (68.3%), triptans (63.0%) or prescription NSAIDs (46.6%) (Table 4); in comparison, among those only on acute therapy, fewer patients used opioids (58.2%) and prescription NSAIDs (40.5%). Triptan use was similar among all users of acute therapy (63.0%) and users of acute therapy only (64.3%). The use of opioids or barbiturates as the first acute migraine therapy was observed in 34.1% of all acute therapy users and in 29.5% of acute therapy-only users. An excessive use of triptans was observed in 1.6% of all acute therapy users and in 1.3% of acute therapy-only users. The excessive use of prescription NSAIDs, opioids and barbiturates based on ICHD-3b (https://www.ihs-headache.org/ichd-guidelines) criteria was observed in 7.1% of all acute therapy users and in 4.1% of acute therapy-only users. When a less strict definition of excessive use (≥ 10 pills a month of prescription NSAIDs, opioids or barbiturates) was applied, 23.6% of all acute therapy users and 12.4% of acute therapy-only users were defined as showing excessive use of medications. Although an excessive use of acute medication was found in < 10% of all patients (7.1% of all patients on acute medication and 4.1% of those only on acute medications), 12.0% of all acute therapy users and 4.7% of acute therapy-only users still had > 5 days of opioid supply per month over a 12-month period (Table 4).