Geomagnetic activity, humidity, temperature and headache: is there any correlation?

Pain and Weather associations - Action Mechanisms; Personalized profiling

It is a well-known hypothesis that weather can influence human health, including pain sensation. The primary meteorological factors are atmospheric pressure, wind, humidity, precipitation, and temperature, which vary from the climate and seasons, but the parameters of space weather (e.g., geomagnetic and cosmic ray activities) also may affect our body condition. Despite a significant number of experimental studies, reviews, and meta-analyses concerning the potential role of weather in pain sensitivity, the findings are heterogeneous and lack consensus. Therefore, rather than attempting a comprehensive analysis of the entire literature on the effects of weather on different pain types, this study highlights the potential action mechanisms of the meteorological factors, and the possible causes of the controversial results. The few data available about the individual evaluations are discussed in detail to reveal the significance of the personalized analysis of the possible relationships between the most available weather parameters and the pain scores. The use of special algorithms may enable the individual integration of different data for a precise outcome concerning the link between pain sensitivity and weather parameters. It is presumed that despite the high level of interindividual differences in response to meteorological parameters, the patients can be clustered in different groups based on their sensitivity to the weather parameters with a possible disparate treatment design. This information may help patients to control their daily activities and aid physicians to plan more valuable management for patients with pain states when the weather conditions change.

Revisiting the connection between Solar eruptions and primary headaches and migraines using Twitter

Many internal and environmental triggers of primary headaches have been proposed, but establishing firm evidence for any of them has proved elusive. Geomagnetic storms, the disturbances of Earth’s magnetic field following Solar eruptions, have been proposed as one such trigger. In this study, we utilized a vast amount of self-reported symptoms from the online social networking service Twitter in order to investigate a purported link between the level of geomagnetic activity and the onset of primary headaches and migraines. We analyzed 63 million keyword-bearing messages posted over the three years covering the maximum of Solar Cycle 24. No correlation has been found despite the large sample size. The simulation reveals that the significant correlation would have emerged even if only 1% of headache (2% of migraine) instances were caused by geomagnetic disturbances, thus placing very low upper limits on the prevalence of this trigger among Twitter users.

Triggers of migraine and tension-type headache

Identification of trigger factors or precipitants is frequently recommended as a basic strategy in the treatment of migraine and tension-type headache (TTH). Trigger factors increase the probability of headache in the short term. Potential trigger factors have been examined most frequently in migraine and less often in TTH. Many of these factors are related to migraine as well as to TTH, but their prevalence may differ in the two headache types. In this chapter, we will review the findings of retrospective as well as of prospective and controlled studies. Taken together, virtually all aspects of life have been suspected to trigger migraine or TTH, but scientific evidence for many of these triggers is poor. Menstruation has a prominent unfavorable role in migraine and possibly in TTH. There is at least some evidence that environmental factors such as weather, lights, noise and odors, stress and other psychological factors, sleeping problems, fatigue and tiredness may play a role. In addition, intake of alcohol, caffeine withdrawal, skipping meals, and possibly dehydration may trigger migraine and TTH in some patients. Scientific evidence is lacking that any other food or food additive plays a relevant role as a trigger factor of headaches.

[Non-alimentary trigger factors of migraine and tension-type headache]

Based on an overview of the literature, this contribution critically discusses the importance of non-alimentary trigger factors of migraine and tension-type headache. Menstruation, environmental factors, psychological effects as well as sleep disorders and fatigue are mentioned most frequently. According to controlled studies, menstruation is indubitably associated with an increased risk of headache. Although a correlation between specific meteorological parameters and the appearance of headaches was established in some patients, the subjective observations of the patients did not however correlate with the objective weather data. Sensory stimuli function as triggers particularly for migraine with aura. Psychological factors, especially stress and everyday pressures, have been confirmed as trigger factors, but further prospective trials addressing this issue would be advantageous. Additional studies are also needed to elucidate the significance of sleep (disorders) and fatigue since their importance as triggers or symptoms of a headache attack has not been conclusively determined.

Environmental variables and the risk of disease

OBJECTIVES

To study the relation between the risk of acute myocardial infarctions (AMI) and meteorological variables and the geomagnetic field, and to make a literature survey of the relation between environmental variables and the occurrence of disease.

STUDY DESIGN

Register study and literature search.

METHODS

Register data on AMI were analysed together with data on temperature, relative humidity, barometric pressure, the Arctic Oscillation, the earth's magnetic field, and changes in these variables. A PubMed search for studies on environmental variables and the occurrence of other diseases was done.

RESULTS

There was no correlation between "static" weather variables and the number of AMIs. A temperature rise of one degree C was associated with an increase in the number of non-fatal AMIs by 1.5%. There was a strong correlation between the AO and the number of AMIs--a one unit increase in AO caused an increase in the number of surviving AMIs by 3.4%, fatal AMIs by 5.1% and the number of sudden cardiac deaths by 8.3%. There was no association between the geomagnetic field and the number of AMIs. The literature study revealed that several other disease states were related to extremes of or changes in weather situations.

CONCLUSIONS

A change in weather, rather than weather extremes, was associated with an increase in the number of AMIs. The environment surrounding us is capable of causing both disease and symptoms. The triggering mechanisms are not known, though.

Biometeorological effects on worker absenteeism

The effects of six biometeorological variables (temperature, precipitation, air pressure, humidity, wind speed, and snow) on plant-wide worker absenteeism rates were investigated using 4 years of daily absence data (n=889). After holding constant temporal variables (years, season, and day of week), and then other biometeorological variables, all but one of the variables under consideration were uniquely and significantly related to absenteeism: temperature (r(partial)=-0.17***), precipitation (r(partial)=0.12***), air pressure (r(partial)=-0.09**), wind speed (r(partial)=0.11*), and snow (r(partial)=0.30***). Humidity (r(partial)=-00, ns) was not uniquely correlated. The adjusted R(2) of .29 (full R=0.55) for the entire model was also significant, illustrating the importance of these exogenous, meteorological variables in developing a prediction model of plant-wide absenteeism.

Toward a rational understanding of migraine trigger factors

The typical migraine patient is exposed to a myriad of migraine triggers on a daily basis. These triggers potentially can act at various sites within the cerebral vasculature and the central nervous system to promote the development of migraine headache. The challenge to the physician is in the identification and avoidance of migraine trigger factors within patients suffering from migraine headache. Only through a rational approach to migraine trigger factors can physicians develop an appropriate treatment strategy for migraine patients.

The influence of a low-fat diet on incidence and severity of migraine headaches

Migraine headaches are a common, debilitating syndrome causing untold suffering and loss of productivity. A review of the literature indicates that high levels of blood lipids and high levels of free fatty acids are among the important factors involved in triggering migraine headaches. Under these conditions, platelet aggregability, which is associated with decreased serotonin and heightened prostaglandin levels, is increased. This leads to vasodilation, the immediate precursor of migraine headache. A high-fat diet is one factor that may directly affect this process. This study, undertaken to evaluate the impact of dietary fat intake on incidence and severity of migraine headache, was conducted over a 12-week period on 54 previously diagnosed migraine headache patients. During the first 28 days, the study subjects recorded all food consumption in a diet diary and maintained a headache diary. At the conclusion of this 28-day baseline period, subjects were individually counseled to limit fat intake to no more than 20 g/day. A 28-day run-in period was allowed for adaptation to the low-fat diet. Results are reported on the final 28-day postintervention period. Subjects significantly decreased the ingestion of dietary fat in grams between baseline (mean 65.9 g/day, p < 0.0001) and the postintervention period (mean 27.8 g/day). The decreased dietary fat intervention was associated with statistically significant decreases in headache frequency, intensity, duration, and medication intake (all p < 0.0001). There was a significant positive correlation between baseline dietary fat intake and headache frequency (r = .44, p = 0.02). This study indicates that a low-fat diet can reduce headache frequency, intensity, and duration and medication intake.

Electrocortical responses of headache patients to the simulation of 10 kHz sferics

Many headache patients believe that weather changes act as pain triggers. Therefore, the present study investigated the psychophysiological influence of an indicator of atmospheric instability, Very Low Frequency (VLF)-sferics, on 32 subjectively weather-sensitive women suffering from migraine attacks and/or tension-type headaches. It was analyzed if sferics exposure is able to induce electrocortical changes as well as headache symptoms. The subjects, who had been divided into two groups, participated in a sferics simulation study. The experimental group (n = 16) underwent a ten-minute exposure to 10kHz-sferics impulses followed by 20 minutes without treatment in order to examine possible prolonged sferics effects. The control group (n = 16) received no treatment. As dependent measures, EEG spectral power was compared between the two groups at six electrode sites (F3/F4; P3/P4; O1/O2). Sferics exposure provoked increases in absolute alpha and beta power during the treatment. The alpha power enhancement was still present at parietal sites at the end of registration (20 minutes after the end of exposure). The stimulation did not induce headache symptoms.

Relationship between suicide and myocardial infarction with regard to changing physical environmental conditions

In recent years, the possible association of changes in mortality from cardiovascular disease and myocardial infarction (MI) and deaths related to violence and the suicide rate has been repeatedly discussed. This study examined the relationship between cosmic physical changes (solar, geomagnetic and other space activity parameters) and changes in the total number of in-hospital and MI-related deaths and deaths from suicide to determine if a relationship exists between the distribution of total and MI-related deaths with suicide over time; some differences in the serotonergic mechanisms involved in the pathogenesis of MI and suicide were also taken into account. All suicides (n = 2359) registered in the State of Israel from 1981 to 1989 (108 months) were analysed and compared with the total number of deaths (n = 15601) and deaths from MI (n = 1573) in a large university hospital over 180 months (1974-1989). The following were the main features of the Results. (1) Monthly suicide rate was correlated with space proton flux (r = 0.42, P = 0.0001) and with geomagnetic activity (r = -0.22, P = 0.03). (2) Total hospital and MI-related deaths were correlated with solar activity parameters (r = 0.35, P < 0.001) and radiowave propagation (r = 0.52-0.44, P < 0.001), an with proton flux (r = -0.3 to -0.26, P < 0.01). (3) Monthly suicide distribution over 108 months was correlated with MI (r = -0.33, P = 0.0005) and total hospital mortality (r = -0.22, P = 0.024). (4) Gender differences were prominent.(ABSTRACT TRUNCATED AT 250 WORDS)