Headache is usually unilateral and pulsating in nature, with a duration that can vary from 2 to 72 hours. Associated symptoms may include nausea, vomiting, photophobia, increased sensitivity to light, phonophobia, increased sensitivity to sound, and pain generally worsens following physical activity.
Up to a third of people with migraines experience aura - a transient visual, sensory, motor, or speech disturbance that shortly precedes the onset of a headache episode. Occasionally an aura can occur without being followed by a migraine.
Migraines are believed to be caused by a mix of environmental and genetic factors. About two thirds of the patients belong to families in which other cases of the same pathology had occurred. Fluctuations in hormone levels may play a role and in fact migraines affect more boys than girls before puberty, but in adults, women with migraines are two to three times more frequent than men.
The predisposition to migraines generally decreases during pregnancy. The exact etiology and pathophysiology of migraine is unknown; however, it is often thought of as a neurovascular disorder. The most accepted theory is related to the increased excitability of the cerebral cortex and abnormal control of pain neurons in the trigeminal nucleus of the brain stem.
The study: Mobile phone electromagnetic radiation and the risk of headache: a systematic review and meta-analysis, published on the International archives of occupational and environmental health, analyzes: "The effects of electromagnetic fields of mobile phones on headaches have attracted researchers during the last decades.
In this systematic review and meta-analysis, major databases including PubMed, Scopus and Web of Science were searched using suitable search terms and PRISMA guidelines to retrieve eligible studies for the effect of mobile phone use on headache.
After the abstract and full-text screening, 33 studies were retrieved and the effect size in terms of odds ratio (OR) was extracted. Between-study heterogeneity was assessed using I2 statistic and Q test, while publication bias was evaluated by funnel plot and Egger's and Begg's tests.
Among 33 eligible studies, 30 eligible studies were included in the meta-analysis. When considering all studies, the pooled effect size of OR = 1.30 (95% CI 1.21-1.39) was obtained, while the heterogeneity between studies was significant.
Subgroup analyzes by considering the age of participants and EMF exposure duration were performed to find the source of heterogeneity. The odds ratios when the age of participants was the variable were 1.33 (95% CI 1.14-1.53) and 1.29 (95% CI 1.20-1.37), for ages> 18 and age ≤ 18 years, respectively.
When EMF exposure duration was considered, subgroup analysis obtained the pooled effect size of OR = 1.41 (95% CI 1.22-1.61) and 1.23 (95% CI 1.12-1.34), for EMF exposure duration> 100 and ≤ 100 minutes per week, respectively.
The pooled effect sizes emphasized the effect of mobile phone use on headaches for all ages and exposure durations. Results revealed that age and exposure duration (mainly call duration), both were the source of heterogeneity between studies.
Furthermore, results showed that increasing call duration and mobile phone use in older individuals increased the risk of headache."