Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0234215 (discomfort)
 24,445 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Histamine has been widely used experimentally to induce headache in healthy subjects and migraine in migraineurs. There is evidence that the vascular effects of histamine are at least partially mediated by nitric oxide (NO). Hence we hypothesized that subjective symptoms and hemodynamic effects of histamine could be reduced by systemic NO-synthase inhibition. We therefore studied the effect of pretreatment with N-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of NO-synthase, or placebo on headache, flush and discomfort scores during histamine infusion. Additionally, blood flow velocities in the middle cerebral and the ophthalmic artery and ocular fundus pulsations were measured. Whereas L-NMMA blunted the effect of histamine in the ophthalmic artery and the ocular circulation, NO-synthase inhibition did not mitigate subjective symptoms. Histamine did not affect mean blood flow velocities in the middle cerebral artery. Hence, we conclude that NO-synthase inhibition reduces the histamine-induced vascular effects in the ocular circulation, but is not sufficient to attenuate or abort the subjective symptoms provoked by histamine infusion.
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PMID:Nitric oxide synthase inhibition in the histamine headache model. 917 Mar 40

This study investigated whether migraineurs are more sensitive to light and sound while headache-free than are healthy people. Fifty-two migraineurs (mean age 39 years) were selected using the International Headache Society diagnostic criteria for migraine. Forty-eight healthy controls were matched for age, sex, and race (mean age 36 years). Visual and auditory discomfort thresholds were measured by exposing subjects to increasing light and sound until they complained of discomfort. There were significant differences between groups in both the light discomfort threshold (P < 0.00005) and the hearing discomfort threshold (P < 0.0005). The thresholds for both were lower in the migraineurs. Overall, for both groups together, there was a significant negative correlation between light discomfort threshold and age (correlation coefficient -0.2276, P = 0.011), but not for the hearing discomfort threshold and age (P = 0.275). The results show that the migraineurs were significantly more sensitive to light and sound when headache-free than were healthy controls. The apparent increased intolerance to light in both groups together noted with increased age, did not apply to the migraine group.
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PMID:Photophobia and phonophobia in migraineurs between attacks. 932 31

Quantitative thresholds for discomfort and pain with monocular and binocular light stimuli were measured in 67 controls and 67 migraine patients (37 migraine with aura and 30 migraine without aura). Patients were more photophobic during attack than outside attack (p < 0.03), and they were more sensitive to light than controls even between attacks (p < or = 0.0001). We found no differences in light sensitivity between migraine with aura and migraine without aura (p > or = 0.93). Unilateral pain affected light sensitivity on both sides. When asked with a questionnaire, 74% of patients answered that they were sensitive to light outside attack and 100% were sensitive during attack. Pain thresholds were generally lower among sensitive than non-sensitive patients (p = 0.004), indicating some agreement between subjective opinion and objective measurements of photophobia. Photophobia seems to be an intrinsic property of migraineurs. It is increased by migraine pain, but seems to be unrelated to migraine characteristics such as nausea, severity of attacks, pain character and pain laterality.
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PMID:Light-induced discomfort and pain in migraine. 939 2

Pericranial muscle tension may contribute to the development of facial discomfort, chronic daily headache, and migraine-type headache. Elimination of pericranial muscle tension may reduce associated myalgia and counteract influences that can trigger secondary headaches which fall within the migraine continuum. Four patients with chronic, predominantly tension-type headaches and associated pericranial muscle tension failed prolonged conventional treatment and, therefore, symptomatic areas were treated with botulinum toxin A. This alleviated myalgia and reduced the severity and frequency of migraine-type headaches with a concomitant reduction in subsequent medical and physical therapy interventions. Judicious use of botulinum toxin A into defined areas of pericranial muscle tension may be useful for reducing primary myalgia and secondary headache.
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PMID:Botulinum toxin A, adjunctive therapy for refractory headaches associated with pericranial muscle tension. 966 53

Quantitative measurement of sound-induced discomfort and pain thresholds showed that migraineurs (n = 65) were significantly more sensitive than headache-free controls (n = 80), both during and outside attack (p < 0.0001). Patients tested with head pain had lower thresholds than those tested without pain (p < 0.01). Migraine with and without aura did not differ as to sound sensitivity. There were no significant differences in thresholds between the symptomatic and nonsymptomatic sides (p > or = 0.78). Patients with unilateral headache or pain of pulsating character were more sensitive than those with bilateral headache or pressing pain (p < 0.05). Phonophobia did not correlate significantly with duration, frequency, or severity of attacks. The main results were in accordance with a questionnaire study concerning subjective evaluation of sound sensitivity. Similarities between phonophobia and photophobia in migraine provide evidence that both phenomena share a common pathophysiological mechanism in this condition.
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PMID:Phonophobia in migraine. 967

Childhood migraine can be the expression of an unconscious attempt of the small patient to show a discomfort which is denied through the defence of somatization. We considered a sample of 73 children, 39 males and 34 females suffering from migraine. We evaluated the presence of emotional disorders through diagnostic interviews consisting of one by one submission of the Anxiety Scale Questionnaire for Evolutive Age and the Children Depression Scale Test. Within our sample we are able to distinguish three groups: a first group negative for both anxiety and depressive disorders, thus defined as control group; a second group presenting anxiety depressive disorders and a third one presenting a mostly depressive symptomatology. We found a significantly higher incidence of migraine in male firstborn children belonging to the group with a condition associated to anxiety and depression.
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PMID:Evaluation of anxiety and depression in childhood migraine. 1071 Aug 29

Performance in migraine with and without visual aura, non-specific headache and headache-free control groups was measured using a visual search task. Data from groups with high and low visual discomfort were also gathered. No pattern, 2 c/deg, 15 c/deg and a grey field were used in different background conditions. Presentation of patterned backgrounds slowed performance for all groups with the 2 c/deg pattern producing greatest interference. Performance of headache groups did not differ from that of the control group in any condition. The high visual discomfort group responded significantly more slowly than other groups with the 2 c/deg background. It was concluded that the presence of visual discomfort, reported on an everyday basis was a better indicator of heightened sensory sensitivity than the occurrence of migraine with or without aura.
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PMID:The influence of pattern interference on performance in migraine and visual discomfort groups. 1116 99

We aimed to estimate primary sensory evoked potential (EP) amplitude, amplitude-intensity functions and habituation in migraine patients compared with healthy control subjects and to investigate the possible relation to check size, sound and light discomfort thresholds, and the time to the next attack. Amplitudes of cortical visual evoked potentials (VEP, check size 8' and 33'), cortical long latency auditory evoked potential (AEP NIP1; 40, 55 and 70 dB SL tones) and brainstem auditory evoked potential (BAEP wave IV-V; 40, 55 and 65 dB SL clicks) were recorded and analysed in a blind and balanced design. The difference between the response to the first and the second half of the stimulus sequence was used as a measure of habituation. Twenty-one migraine patients (16 women and five men, mean age 39.3 years, six with aura, 15 without aura) and 22 sex- and age-matched healthy control subjects were studied (18 women and four men, mean age 39.5 years). Low sound discomfort threshold correlated significantly with low levels of BAEP wave IV-V amplitude habituation (r = -0.30, P = 0.05). VEP an AEP amplitudes, habituation, and amplitude-intensity function (ASF) slopes did not differ between groups when ANOVA main factors were considered. Control group VEP habituation was found for small check stimuli (P = 0.04), while potentiation was observed for medium sized checks (P = 0.02). The eight migraine patients who experienced headache within 24 h after the test tended to have increased BAEP wave IV-V ASF slopes (P = 0.08). This subgroup did also have a significant VEP habituation to small checks (P = 0.04). No correlation was found between different modalities. These results suggest that: (i) VEP habituation/potentiation state and brainstem activatio state may depend on the attack-interval cycle in migraine; (ii) VEP habituation/ potentiation may depend on spatial stimulus frequency; (iii) phonophobia (and possibly photophobia) may depend more on subcortical (brainstem) function than on cortical mechanisms; (iv) low cortical preactivation in migraine could not be confirmed; (v) EP habituation and ASF analysis may reflect sensory modality-specific, not generalized, central nervous system states in migraine and healthy control subjects.
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PMID:Visual, long-latency auditory and brainstem auditory evoked potentials in migraine: relation to pattern size, stimulus intensity, sound and light discomfort thresholds and pre-attack state. 1116 10

Questions about discomfort or pain produced by various stimuli (e.g., light, sound, exercise, neck movements) are currently used to differentiate between various primary headache disorders. In order to evaluate the usefulness of differences in sensitivity to physical stimuli in headache diagnosis, the answers to a questionnaire about sensitivity to various stimuli were compared in 68 patients with migraine, 45 with tension-type headache, 46 with cluster headache, and 23 patients with cervicogenic headache, and in 71 controls. Even among controls, a high proportion reported that many of these stimuli could elicit some degree of discomfort or pain. Without headache, migraineurs differed from the other patients with headache and controls mainly in their increased sensitivity to light. With headache, patients with tension-type headache were the least sensitive and migraineurs were the most sensitive to all stimuli, except for stimuli stemming from neck movements, to which patients with cervicogenic headache were most sensitive. Migraineurs also reported the highest degree of sensitivity regarding aggravation and provocation of headache. However, the most striking finding was that all patient groups, cluster headache in particular, became significantly more sensitive with headache than without headache to almost all stimulus categories. This may indicate that these headaches share important pathogenetic mechanisms. The fact that no headache had a very specific sensitivity profile may point to weaknesses of present headache classification systems.
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PMID:Sensitivity to various stimuli in primary headaches: a questionnaire study. 1097 72

The response of different visual discomfort groups to a range of spatial frequencies at threshold and suprathreshold was investigated. In experiment 1, a paired-comparison task was conducted. The high visual discomfort group judged a spatial frequency of 4 cycles deg-1 as the most perceptually distorted and somatically unpleasant to view. The moderate and low visual discomfort groups judged 8 and 12 cycles deg-1 as more perceptually and somatically unpleasant to view than lower spatial frequencies. In experiment 2, the spatial contrast-sensitivity function (CSF) for the high visual discomfort group was depressed for spatial frequencies between 1 and 12 cycles deg-1 in comparison with the moderate and low visual discomfort groups. When these same spatial frequencies were modulated at 6 Hz, CSFs were the same for all groups. These results are discussed in relation to a failure of inhibition across spatial-frequency channels in the high visual discomfort group. This may be explained by a more generalised parvocellular system processing deficit. Possible similarities between some forms of migraine and visual discomfort are highlighted.
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PMID:Visual discomfort: the influence of spatial frequency. 1143 Feb 42


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