For the purposes of this study, those patients who have symptoms of headaches on a minimum of 10 days a month are addressed, and chronic headaches are generally defined as a patient having a headache 15 days of the month for at least three months.
Clark, Chelsea (2013) "The temporal relationship between daily stress and delayed modulation of chronic headache pain," Introduction Headache pain affects a large portion of the population and can be very disabling for those who experience it. About 4% of general practitioner visits in the medical field are made up of headache consultations, and one of the most common reasons for referral to a neurologist is headache pain [1]. It is estimated that greater than 10% of the entire global population suffers from migraine, about 40% suffer from tension-type headache (TTH), and 5% suffer from chronic daily headache, although these estimates vary widely between studies [2-5]. Primary headache refers to headache disorders with no exogenous cause [5]. Secondary headaches, which are caused by some other condition, often produce very extreme, even life-threatening acute pain. However, the pain from primary headaches should not be overlooked; primary headaches very often greatly reduce quality of life and result in significant long-term disability. Although there are many types of primary headache, the most prevalent are migraine and tension-type headache [6]. Migraines are characterized by a headache with associated features, which can include throbbing pain, sensitivity to sensory stimuli such as light or sound, or sensitivity to head movement itself. TTH does not present with these associated features [5]. For migraine sufferers, head pain stems from an inherited tendency to have headaches. Environmental factors, or 'triggers', are very influential on headache patterns of migraine patients. It seems that the brain of a migraine sufferer is very sensitive to environmental stimuli and less tolerant to changes in the environment [5]. In general, most headache patients experience fluctuations in headache pain intensity, duration, and frequency. There are many known factors that influence this variability. For example, many foods can serve as triggers, and also alcohol, weather, exercise, stress, and menstruation can have an effect [5, 7]. Primary headaches can often become long-term problems. There is much debate over what should be considered a chronic headache disorder. Because headaches are generally presented in the form of " attacks " , it is hard to categorize when these attacks become a chronic condition. Chronic headaches are generally defined as a patient having a headache 15 days of the month for at least three months [8]. For the purposes of this study, we aim to address those patients who have symptoms of headaches on a minimum of 10 days a month, …