Sleep disorders comorbidity

The common structural and neurotransmitter pathways between headache and sleep accounted for the strict comorbidities between these two conditions, since it is mediated by the structural co-alteration of serotonergic and dopaminergic pathways that affect migraine and sleep. Both an excess or a lack of sleep could be trigger for a migraine or headache attack, but also sleep could be a relieving factor for headache. Therefore, the link between sleep and headache or migraine is complex and could not be simply explained by the common neurotransmitters alterations. Different comorbid sleep disorders, like insomnia, parasomnias (sleepwalking, sleep terrors, enuresis), restless legs syndrome, periodic limb movements, and narcolepsy, could have distinctive pathogenetic causes. Alteration of sleep architecture, sleep fragmentation or hypoxia linked to sleep apnea are common recognized factors affecting headache or migraine. Often the treatment of a sleep disorder could resolve or improve headache and on the other hand the drugs used for migraine/headache prophylaxis could improve sleep