Clinical features of headache associated with mobile phone use: a cross-sectional study in university students

A 14-item questionnaire investigating MP use and headache was administered to 247 medical students at Hallym University, Korea. Individual telephone interviews were subsequently conducted with those participants who reported HAMP more than 10 times during the last 1 year on the clinical features of HAMP. We defined HAMP as a headache attack during MP use or within 1 hour after MP use.In total, 214 (86.6%) students completed and returned the questionnaire. Forty (18.9%) students experienced HAMP more than 10 times during the last 1 year in the questionnaire survey. In subsequent telephone interviews, 37 (97.4%) interviewed participants reported that HAMP was triggered by prolonged MP use. HAMP was usually dull or pressing in quality (30 of 38, 79.0%), localised ipsilateral to the side of MP use (32 of 38, 84.2%), and associated with a burning sensation (24 of 38, 63.2%).We found that HAMP usually showed stereotyped clinical features including mild intensity, a dull or pressing quality, localisation ipsilateral to the side of MP use, provocation by prolonged MP use and often accompanied by a burning sensation.The use of mobile phones (MPs) has increased dramatically, with over 3 billion people currently using MPs worldwide [1]. In Korea, 92.9% of the population of approximately 48.4 million people used MPs in 2008 [2]. With the increased use of MPs, some users have reported the development of symptoms such as headache, sleep disturbance, memory loss, dizziness, and burning sensations during or after MP use [3,4]. Several epidemiological studies have suggested that MP use may be related to the occurrence of these symptoms [5].Experiments aimed at explaining these symptoms have shown changes in cerebral blood flow [6,7], altered electroencephalogram (EEG) patterns [3,5,6], and changes in responses to transcranial magnetic stimulation [8] resulting from MP use. A series of double-blind, sham-controlled studies have reported no significant differences in headache provocat