Suvidha Pain Management : Specialities-Migraine

Migraine is a chronic disorder characterized by moderate to severe headaches together with nausea. It is believed to be a neurovascular
disorder. A typical migraine headache is unilateral (affecting one half of the head) and pulsating in nature, lasting from 2 to 72 hours. Symptoms include nausea, vomiting, photophobia (increased sensitivity to light) and phonophobia (increased sensitivity to sound); the symptoms are generally aggravated by routine activity. Approximately one-third of people who suffer from migraine headaches perceive an aura: transient visual, sensory, language, or motor disturbance which signal that the migraine will occur soon.
Migraines are related to a mix of environmental and genetic factors. About two-thirds of cases run in families. Fluctuating hormone levels may also play a role: migraine affects approximately equal numbers of girls and boys before puberty, but about two to three times more women than men. Propensity to migraine headache sometimes disappears during pregnancy, but in some women, migraines may become more frequent. The underlying mechanisms of migraines are unknown. The most supported theory is that migraine is related to hyperexcitability of the cerebral cortex and/or abnormal control of pain neurons in the trigeminal nucleus of the brainstem.
Initial recommended management is with analgesics for the headache, an antiemetic for the nausea, and the avoidance of triggers. Specific agents such as triptans or ergotamines may be used by those for whom simple analgesics are not effective. Globally, more than 10% of the population is affected by migraine at some point in life.

Symptoms

Migraines typically present with self-limited, recurrent severe headache associated with autonomic symptoms.About 15-30% of people experience migraines with an aura.The severity of the pain, duration of the headache, and frequency of attacks is variable.A migraine lasting longer than 72 hours is termed status migrainosus.There are four possible phases to a migraine, although not all the phases are necessarily experienced:

1- The prodrome, which occurs hours or days before the headache

2- The aura, which immediately precedes the headache

3- The pain phase, also known as headache phase

4- The postdrome

Causes

The underlying cause of migraines is unknown however they are believed to be related to a mix of environmental and genetics factors. They do run in families in about two-thirds of cases and rarely occur due to a single gene defect. Many biological events or triggers have been associated.

Genetics

Studies of twins indicate a 34 to 51 percent genetic influence of likelyhood to develop migraine headaches. A number of specific variants of genes increase the risk by a small to moderate amount.

Single gene disorders that result in migraines are rare. One of these is known as familial hemiplegic migraine, a type of migraine with aura, which is inherited in a autosomal dominant fashion.It is related to disorders of gene coding for proteins involved in ion transport. Another is CADASIL syndrome or cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

Triggers

Migraines may be induced by triggers, with some reporting it as an influence in a minority of cases and others the majority. Many things have been labeled as triggers, however the strength and significance of these relationships are uncertain. A trigger may occur up to 24 hours prior to the onset of symptoms.

Physiological

Common triggers quoted are stress, hunger, and fatigue (these equally contribute to tension headaches). Migraines are more likely to occur around menstruation. Other hormonal influences, such as menarche, oral contraceptive use, pregnancy, perimenopause, and menopause, also play a role. Migraines typically do not occur during the second and third trimesters or following menopause.

Dietary

Reviews of dietary triggers have found that evidence, mostly relying on subjective assessments and is not rigorous enough to prove or disprove any particular triggers. Regarding specific agents there does not appear to be evidence for an effect of tyramine on migraine and while monosodium glutamate (MSG) is frequently reported as a dietary trigger evidence does not consistently support this.

Environmental

Potential triggers in the indoor and outdoor environment concluded the overall evidence was of poor quality, but nevertheless suggested people with migraines take some preventative measures related to indoor air quality and lighting.

Migraine