Headache

SYNOPSIS

A population‐based epidemiological study of the prevalence of headache in a sample of 24,682 adults was carried out in Finland. Enquiries were made concerning the frequency of headache, migraine and characteristics of headache attacks in a questionnaire survey in 1981. Headache was classified as migraine, and headache without migrainous features. Possible somatic causes of headache were excluded by record‐linkage with three nation‐wide medical registries.

The prevalence of both headache types depended on age and gender. Among women the overall prevalence of migraine was 10.1% with a maximum of 11.5% in the 40‐49 age group. The prevalence rate among men was 2.5% and the female/male gender ratio was 4.0. Women with migraine had an average of 52.5 headache occasions during a year and men with migraine 61 headache occasions per year. At the individual level, headache without migrainous features was least invalidating. There were only 16.5 headache occasions a year among women and 11.5 among men. However, from a population perspective headache without migrainous features accounted for 46.5% of all headache occasions among women and for 60.8% among men. Thus, from the public health viewpoint, studies of “non‐clinical” headache, e.g. headache without migrainous features should be emphasized.

Objective.—The main objective of this study is to determine whether change in migraine frequency is correlated with a denervation pattern of the corrugator muscle after local botulinum toxin type A injections.

Background.—Recent studies suggest botulinum toxin type A is effective in preventing migraine. Relaxation of the corrugator muscle may be one of multiple targets of botulinum toxin type A in relieving migraine pain.

Methods.—The pretreatment amplitude of the compound muscle action potential (CMAP) was obtained in 10 patients with a migraine frequency of two to six attacks per month following stimulation of the temporal branch of the facial nerve. Patients were subsequently injected with 20 units of botulinum toxin type A at predefined sites in the procerus and corrugator muscles. CMAP was obtained on days 7, 30, 60, and 90 after injection. Migraine frequency, as reported in headache diaries, was compared with the amplitudes obtained.

Results.—A 50% decrease in CMAP was demonstrated in the total group by day 7. Maximal decline of CMAP was observed by day 30, and was sustained at day 60. Migraine frequency declined by 50% or more in 7 of 10 patients by day 60. Migraine response to botulinum toxin type A treatment did not correlate with the denervation pattern.

Conclusion.—Relaxation of the corrugator muscles is not solely responsible for the pain relief in migraine patients treated with botulinum toxin type A.

SYNOPSIS

Migraine has no single cause. It can be seen as a reaction of the organism, probably determined by the hypothalamus and released by a variety of extrinsic and intrinsic factors. Several factors may determine attacks at different times within a patient's lifetime. Vascular reactions are secondary to the primary cerebral mechanism, and account for many of the symptoms, notably the headache. The prodrome, aura, and the incubation during sleep are part of the attack.

Emotional disturbance is the commonest single trigger mechanism, and is the most important cause of frequent and severe attacks. There is, however, nothing specific about the emotional stimulus, nor is there a consistent personality type in migraine subjects. Certain personality reactions and patterns of behavior recur in migraine subjects; a tendency to anxiety reactions, sensitivity to stress and difficulty in handling aggressive and hostile drives. In this respect, migraine is similar to many other “psychosomatic diseases” without demonstrable pathology but characterized by disorders of homeostasis. In some patients extrinsic physical and biochemical precipitants are prominent and the “psychosomatic element” is slight. In most migraine patients, however, psychologic factors are important but are secondary rather than precipitating etiologic agents.

SYNOPSIS

Muscle contraction headache and migraine patients were compared for symptoms of muscular and vascular activity, and responsiveness to frontalis electromyogram (EMG) biofeedback therapy. Locations of head pain were non‐specific to the diagnostic groups. Migraine patients had higher frontalis EMG activity than muscle contraction headache patients and headache‐free controls. Both headache groups had higher neck EMG activity than controls. Pulse velocities in the superficial temporal arteries were similar in the two headache patient groups but different from controls. It is suggested that muscle contraction headache and migraine patients have similar physiologic predisposition for headaches. Further support for similar predisposition in the two groups was provided by the frontalis EMG biofeedback results which showed this treatment to be equally effective for both groups.

SYNOPSIS

Typically migraine and muscle contraction headaches are thought to be different disorders. Recently some investigators have argued that these headache categories are quantitatively, but not qualitatively distinct. Studies of vasomotor and electromyographic (EMG) reflexes and treatments for these headaches were reviewed to elucidate similarities and differences. Similarities include for both types of headaches high levels of tension in the muscles of the head and neck, a vasoconstrictive component, a responsiveness to treatment by relaxation or reduction of frontalis muscle tension. Differences between migraine and muscle contraction headaches relate to the status of the temporal artery between and during headaches and the standard medical treatments used for each. Systematic research is needed to establish if fundamental differences exist between these two major categories of headache.

SYNOPSIS

Thirty‐two patients with chronic cluster headache, not responding to conventional therapy, were treated with lithium carbonate for 32 weeks.

Treatment was discontinued in 4 cases because of intolerable side effects. Marked and continued improvement occurred in 27 of 28 patients throughout the treatment period. Twenty‐five percent of all patients had mild or transient side effects without increased serum lithium levels. Long‐term prophylactic lithium maintenance treatment is efficacious in selected cases of chronic cluster headache.

SYNOPSIS

Characteristics of headache sufferers and their headaches were investigated in a random sample of general practice patients by way of postal questionnaire.

The results are consistent with previous studies in respect to prevalence, and the relation of headache to sex, age, and social class. Features of headache were found to be more closely associated with headache severity and sufferer's sex, than diagnositic group. Little justification was found for sharp division into migraine and muscle tension groups.

SYNOPSIS

Based on clinical features, a group of 31 patients with cluster headache was divided into 1) episodic cluster headache, with months or years of headache free intervals, 2) chronic cluster headache without significant headache free intervals. Chronic type could be subdivided into primary and secondary varieties, secondary being a transformation from episodic cluster headache. A clinical trial of Lithium Carbonate was undertaken. Blood levels of lithium were determined at regular intervals to monitor the therapeutic dosage. Lithium was found to be an effective prophylactic agent in both episodic and chronic cluster headache patients. The percentage of improvement based on headache index was as follows: 55% of patients had more than 90% improvement; 10% of patients showed 60–90% improvement; 15% of patients showed 25–60% improvement; and 20% no improvement. Effectiveness of lithium was evident in less than a week after the initiation of treatment in those who responded. 55% of patients showed mild side effects such as tremor, nausea, diarrhea, abdominal discomfort and lethargy. Only one patient had serious side effects which needed discontinuation of therapy.The beneficial effect of lithium on cluster headaches appear to be independent of its anti‐depressant action. Mechanism of action of lithium in cluster headache is not clear.