Medication overuse headache in Europe and Latin America: general demographic and clinical characteristics, referral pathways and national distribution of painkillers in a descriptive, multinational, multicenter study

Table 1 Baseline Characteristics

		Denmark	Germany	Italy	Spain	Argentina	Chile	Europe	Latin America	p-value	Total
N		125	101	117	92	126	108	435	234		669
Age, years	<30	13.6	26.7	18.8	15.2	31.2	20.4	18.4	26.1		21.1
	30–55	71.2	63.4	72.6	70.7	58.4	70.4	69.7	63.7	0.058	67.7
	>55	15.2	9.9	8.5	14.1	10.4	9.3	12.0	9.8		11.2
Gender, female		77.6	74.3	82.1	80.4	80.2	81.5	78.6	80.8	0.55	79.4
High educational level^a		87.2	40.4	71.8	49.5	80.2	67.6	64.4	74.4	0.009*	67.9
Marital status, married		70.4	52.0	58.1	68.1	50.8	55.6	62.4	53.0	0.021*	59.1
Primary headache diagnosis	Migraine^b	30.4	80.2	82.9	46.7	72.2	79.6	59.5	75.6		65.2
	TTH^b	26.4	2.0	0.9	16.3	5.6	1.9	11.7	3.8	<0.001*	9.0
	Migraine and TTH^b	43.2	17.8	16.2	37.0	22.2	18.5	28.7	20.5		25.9
Age of onset of primary headache, years		23.4 (13.0)	18.1 (9.2)	14.1 (6.0)	18.9 (9.9)	16.2 (6.2)	19.7 (10.1)	18.8 (10.5)	17.8 (8.4)	0.22	18.4 (9.8)
Headache frequency, days/month^c		25.8 (5.5)	25.1 (5.6)	23.3 (6.0)	23.6 (5.0)	22.1 (6.4)	23.0 (5.7)	24.5 (5.7)	22.5 (6.1)	<0.001*	23.8 (5.9)
Duration of overuse in years	<1	13.6	21.8	11.1	16.3	19.0	22.2	15.4	20.5		17.2
	1–5	67.2	54.5	58.1	57.6	61.9	57.4	59.8	59.8	0.13	59.8
	>5	19.2	22.4	30.8	26.1	19.0	20.4	24.8	19.7		23.0
EEG^d		7.3	31.8	0.9	4.7	8.0	2.8	10.0	5.6	0.055	8.4
Scans (CT and MR)^d		29.3	42.3	20.5	36.4	40.0	21.3	31.0	31.3	0.93	31.1
X-rays^d		5.7	21.2	2.6	14.1	12.8	0.9	9.8	7.3	0.32	8.9

Age, gender, educational level, marital status, primary headache type: Proportion of patients in percent. Age of onset of primary headache and headache frequency: Mean (SD). Duration of overuse: Percent of patients categorized into three intervals. EEG, Scans and X-rays: Percent of patients, who had these instrumental investigations performed in the year preceding therapy
TTH tension type headache, EEG electro encephalogram, CT computer tomography scan, MR magnetic resonance scan
^aHigh educational level = High/technical school or university degree
^bMigraine = Migraine with aura, migraine without aura and chronic migraine. TTH = episodic and chronic forms
^cHeadache frequencies refer to the time of inclusion in the study and thereby to the MOH diagnosis
^d N = 643
*p < 0.05. p-values correspond to comparison between Europe and Latin America

ISSN: 1129-2377