The burden of headache disorders in Nepal: estimates from a population-based survey

Table 3 Population-level disability (adults aged 18–65 years), by headache type

	Migraine	Tension-type headache	Probable medication-overuse headache
	n = 728 ≥ 24 h’ duration: n = 289; <24 h’ duration: n = 439	n = 863	n= 46 “never goes away”: n = 17; other: n = 29
Reported mean headache frequency [HF] (d/m)	2.3 (HF1 = 2.38, HF2 = 2.27)	1.8	23.1 (HF1 = 30, HF2 = 19.1)
Reported mean attack duration [D] (h)	33.6 (D1 = 57.1, D2 = 12.2)	16.0	12.1 (D1 = 24.0, D2 = 5.04)
Mean attack frequency [AF] (per month) (see text for explanation)	AF1 = 1, AF2 = 2.27	1.8	AF1 = 30, AF2 = 19.1
Mean absolute time in ictal state [T_abs = AF*D] (h/m)	Weighted mean of AF1D1 and AF2D2 = 39.36	AF*D = 28.8	Weighted mean of AF1D1 and AF2D2 = 326.8
Mean time in ictal state as proportion of total time T_pro = (T_abs12)/(36524)] (%)	5.4	3.9	44.7
Disability weight [DW] (from GBD 2013 [3]	0.441	0.037	0.217
Mean disability per person with headache DIS_per = T_pro*DW] (%)	2.4	0.15	9.7
Prevalence in adults aged 18–65 years [P] (%)	34.1	41.5	2.1
Disability in population [DIS_pop = DIS_per * P] (%)	0.81	0.06	0.20

For migraine, HF1, D1 and AF1 refer to those with attacks of ≥24 h’ duration, HF2, D2 and AF2 to those with attacks of <24 h’ duration; for probable medication-overuse headache, HF1, D1 and AF1 refer to those who report headache that never goes away, HF2, D2 and AF2 to those with headache of determinable duration; D days, m month, h hours

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