Economic burden and risk factors of migraine disease progression in the US: a retrospective analysis of a commercial payer database

Figures & data

Figure 1. Study sample attrition.

Table 1. Patient characteristics.

Characteristic	Prevention-eligible EM progressed to CM (n = 5,790)	Non-progressed prevention-eligible EM (n = 119,646)
Age, mean years (SD)	42.3 (11.7)	43.4 (12.5)*
Sex, % female	87.9%	84.3%*
Geographic region, %*
Northeast	28.6%	24.9%
Midwest	23.1%	25.5%
South	37.2%	39.6%
West	11.1%	10.0%
Payer type, %
Commercial	58.4%	57.2%
Self-insured	3.2%	3.6%
Medicare Advantage	0.3%	0.3%
Medicaid	37.4%	38.3%
Unknown	0.8%	0.6%
Charlson Comorbidity Index (CCI), mean (SD)	0.4 (1.0)	0.5 (1.0)*
Baseline comorbid conditions, %
Asthma	10.4%	9.9%
Anxiety	19.1%	19.2%
Cardiac arrhythmia	4.7%	5.7%*
Chronic pain/fibromyalgia	17.5%	13.5*
Depression	24.1%	22.4%*
Diabetes	5.9%	6.8%*
Dyslipidemia  (including hyperlipidemia)	22.6%	26.0%*
Hypertension	19.9%	25.5%*
Osteoarthritis	44.2%	40.3%
Sleep disorders	16.2%	14.5%
Smoking or history of smoking	6.5%	7.5%*
Thyroid disease	13.4%	12.5%*
Baseline migraine medication use, %
Acute medications  (specific & non-specific)**	81.5%	72.4%*
Preventive medications***	66.2%	61.9%*

* Statistically significant (i.e. p < 0.05). Univariate analyses were conducted with 2-sample t-tests to compare mean values. Chi-square tests/Fisher exact tests were used to compare categorical variables.

** Acute migraine medications included triptans; ergotamine/dihydroergotamine; isometheptene mucate; NSAIDs; butalbital combination analgesics; neuroleptics/antiemetics; opioids.

*** Preventive migraine medications included antidepressants (e.g. amitriptyline, SSRIs, other (e.g. mirtazapine, venlafaxine, phenelzine); antihypertensives (e.g. propranolol, lisinopril, candesartan, calcium channel blockers); anticonvulsants (i.e. gabapentin, topiramate, divalproex sodium, sodium valproate); onabotulinumtoxin A.

Figure 2. All-cause healthcare costs by medical service type before vs after progression. *p < 0.0001.

Table 2. All-cause healthcare resource utilization and costs over the 24-month follow-up period (per patient per month) before vs after progression.

	Prevention-eligible EM before progression (n = 5,790)	Prevention-eligible EM after progression (n = 5,790)
Total number of healthcare visits and prescriptions among all patients
Mean (SD)	6.0 (3.8)	7.2 (5.6)*
Median	5.2	5.8*
Total healthcare costs among all patients
Mean (SD)	$1,414 ($2,456)	$1,790 ($3,788)*
Median	$779	$874*
Outpatient visits
Incidence of ≥1 visit, %	99.9%	99.9%
Number of visits among all patients
Mean (SD)	2.6 (2.3)	3.1 (3.3)*
Median	2.0	2.2*
Number of visits among those with ≥1 visit
Mean (SD)	2.6 (2.3)	3.1 (3.3)*
Median	2.0	2.2*
Outpatient visit costs
Total costs among all patients
Mean (SD)	$753 ($1,428)	$999 ($2,277)
Median	$424	$493
Total outpatient costs among those with ≥1 visit
Mean (SD)	$754 ($1,428)	$1,000 ($2,278)*
Median	$424	$493*
Physician office visits
Incidence of ≥1 visit, %	99.9%	99.1%*
Number of visits among all patients
Mean (SD)	1.6 (1.5)	1.9 (2.4)*
Median	1.1	1.3*
Number of visits among those with ≥1 visit
Mean (SD)	1.6 (1.5)	2.0 (2.4)*
Median	1.1	1.3*
Physician office visit costs
Total costs among all patients
Mean (SD)	$192 ($202)	$258 ($504)*
Median	$135	$153*
Total costs among those with ≥1 visit
Mean (SD)	$192 ($202)	$261 ($505)*
Median	$135	$154*
Emergency department visits
Incidence of ≥1 visit, %	45.0%	23.8%*
Number of visits among all patients
Mean (SD)	0.1 (0.2)	0.1 (0.3)
Median	0.0	0.0*
Number of visits among those with ≥1 visit
Mean (SD)	0.2 (0.3)	0.3 (0.6)*
Median	0.1	0.2*
Emergency department visit costs
Total costs among all patients
Mean (SD)	$92 ($320)	$94 ($466)
Median	0.0	0.0*
Total costs among those with ≥1 visit
Mean (SD)	$204 ($453)	$393 ($892)*
Median	$92	$156*
Inpatient visits
Incidence of ≥1 visit, %	14.3%	6.7%*
Number of visits among all patients
Mean (SD)	0.0 (0.1)	0.0 (0.1)*
Median	0.0	0.0*
Number of visits among those with ≥1 visit
Mean (SD)	0.1 (0.1)	0.3 (0.5)*
Median	0.1	0.1*
Inpatient visit costs
Total costs among all patients
Mean (SD)	$251 ($1,284)	$300 ($2,272)
Median	$0	$0*
Total costs among those with ≥1 visit
Mean (SD)	$1,748 ($2,981)	$4,474 ($7,646)*
Median	$905	$2,009*
Pharmacy utilization (outpatient)	100.0%	97.5%
Incidence of ≥1 prescription, %
Number of prescriptions among all patients	3.4 (2.2)	4.0 (3.2)*
Mean (SD)	2.9	3.3*
Median
Number of prescriptions among those with ≥1 prescription
Mean (SD)	3.4 (2.2)	4.1 (3.2)*
Median	2.9	3.4*
Pharmacy costs (outpatient)
Total costs among all patients
Mean (SD)	$318 ($553)	$398 ($804)
Median	$168	$175
Total costs among those with ≥1 prescription
Mean (SD)	$318 ($553)	$408 ($812)*
Median	$168	$183*

* Statistically significant (i.e. p < 0.05). Paired t-tests were used to compare mean values before and after progression. Wilcoxon signed-rank tests were used to compare median values. McNemar’s tests were used to compare categorical variables. For outcomes reported among users (e.g. patients with ≥1 prescription), independent sample tests were used.

Figure 3. Risk factors associated with migraine progression from prevention-eligible EM to CM. The HRs are adjusted for potential confounders in the model such as demographics, baseline (12-month pre-index) comorbidities, medication use, and costs; also adjusted for region, payer type, and number of unique classes of preventive medication use at baseline (not shown in the figure).