Table 2.

Number of migraine days per month, age-at-onset of migraine, and number of days with medication compared across groups with an increasing genetic load (reflected by the proportion of affected parents).

	Total group of migraine patients	Subgroups by parents’ migraine status			Jonckheere- Terpstra test*
	No parent affected	One parent Affected	Both parents affected
Number of migraine days/ month, median (IQR)	4.0 (2.0–8.0)	4.0 (2.0–7.0)	4.0 (2.0–7.3)	4.0 (2.0–9.0)	p = 0.41
Age-at-onset of migraine, median (IQR) (years)	16.0 (12.0–24.0)	18.0 (12.0–27.0)	16.0 (12.0–22.0)	14.0 (11.0–20.0)	p < 0.001
Number of days of acute headache medication use, median (IQR) (days/ month)
Combined total	5.0 (2.0–10.0)	4.0 (2.0–9.0)	5.0 (2.0–10.0)	6.0 (2.0–12.0)	p = 0.006
Simple analgesics	4.0 (1.0–8.0)	3.0 (1.0–7.0)	4.0 (2.0–8.0)	5.0 (1.0–10.0)	p < 0.001
Triptans	2.0 (0.0–6.0)	2.0 (0.0–6.0)	2.0 (0.0–6.0)	2.0 (0.0–6.0)	p = 0.82

^*Jonckheere-Terpstra test comparing distribution of presented variables over the categories of: 0 = no parents affected; 1 = one parent affected; 2 = both parents affected with migraine.

IQR: interquartile range.