Autonomic responses to tooth clenching and handgrip test.

OBJECTIVE: The aim was to study the differences in autonomic nervous system activation between maximal tooth clenching task and handgrip test during and after the tasks. Also, the possible activation of trigeminocardiac reflex during the clenching task was explored. MATERIAL AND METHODS: We compared autonomic responses to maximal tooth clenching and handgrip in 28 participants. Responses in heart rate variability, heart rate, and blood pressure were evaluated before, during, and after tests. Although all study participants were considered healthy during recruitment, 14 of them showed painful temporomandibular disorders in the clinical examination, which was taken into account in the analyses. RESULTS: Handgrip and tooth clenching caused similar autonomic responses. However, tooth clenching seemed to activate the trigeminocardiac reflex shown as clenching-related vagal activation. The painful signs of temporomandibular disorders may interfere with the heart rate variability both at the baseline and during both tests causing significant variation in them. CONCLUSIONS: Both handgrip and tooth clenching affect the autonomic nervous system function. Tooth clenching differs from the handgrip due to trigeminocardiac reflex. Painful signs of temporomandibular disorders are interfering with the results of the tests and maybe underestimated in the studies of autonomic responses to both tasks.

Electrocardiographic findings in migraineurs: results of the Finnish Health 2000 survey.

BACKGROUND: The precise relation between migraine and cardiovascular diseases remains unknown, but cardiac autonomic regulation as reflected by electrocardiography is poorly studied in migraineurs. AIMS OF THE STUDY: To search whether electrocardiographic findings may elucidate the mechanisms linking migraine with cardiovascular diseases. METHODS: We compared electrocardiographic findings in headache-free subjects (n=5,317) and people with migraine (n=490) in a Finnish population cohort. RESULTS: The frequency of cardiac rhythm and conduction disorders did not differ between the groups but left ventricular hypertrophy was more often seen in migraineurs than in non-migraineurs (odds ratio (OR)=1.32, 95% confidence interval (CI) 1.0; 1.74, p<0.05). In migraineurs reporting frequent attacks, cardiovascular diseases were associated with longer QTc intervals (p<0.05). After excluding confounders, migraineurs had longer PR intervals (160.3 vs 159.8 ms, mean difference (MD)=3.14, 95% CI 0.65; 5.62, p<0.05) than non-migraineurs. PR intervals (MD=6.6, CI 1.51; 11.68, p<0.05) and the probability of left ventricular hypertrophy (OR=1.98, CI 1.2; 3.26, p<0.05) were different in males with and without migraine, especially in patients with frequent attacks, but not in females. CONCLUSIONS: Our findings support the notion that there are interactions between migraine and cardiovascular disorders and suggest that electrocardiographic screening in migraineurs should be considered during clinical work-up.

Left ventricular hypertrophy and other cardiac risk factors in migraineurs.

BACKGROUND: The influence of cardiovascular risk factors on the probability of cardiovascular diseases in migraineurs is still being discussed. AIMS OF THE STUDY: To further elucidate the mechanisms of these relationships, we assessed the associations between migraine and cardiovascular risk factors, including those that have been recently shown to improve the prediction of cardiovascular events. METHODS: We used the data of the Finnish Health 2000 Survey (BRIF8901), consisting of 5737 subjects aged 30 years or older. In total, 488 participants reported migraine. In addition to conventional cardiovascular risk factors, educational attainment, presence of electrocardiographic signs of left ventricular hypertrophy and hemoglobin A1c were also included in the logistic regression analyses. RESULTS: Migraine was found to be associated with female sex (Odds ratio (OR) = 3.75, p < .001), lower age (B = 0.99, p < .001), lower high-density lipoprotein cholesterol (OR = 1.23, p < .05), higher diastolic blood pressure (OR = 1.31, p < .05), and left ventricular hypertrophy (OR = 1.32, p < .05), the probability of the last one increasing with migraine attack frequency. CONCLUSIONS: Left ventricular hypertrophy, most probably as a consequence of migraine-related arterial hypertension and dyslipidemia, may play a role in the relationship between migraine and cardiovascular events. The nature of this finding calls for further studies.

Autonomic responses to tooth clenching in migraineurs-augmented trigeminocardiac reflex?

BACKGROUND: Systemic autonomic changes are well known in migraineurs. Also, masticatory disorders are reported to be associated with migraine. However, if those phenomena are interrelated, and how, is unclear. Moreover, the knowledge on the autonomic responses to masticatory stimuli in migraineurs is limited. OBJECTIVE: To investigate tooth clenching-related cardiac autonomic regulation in migraineurs. METHODS: We compared maximal tooth clenching-induced systemic autonomic responses, indicated by heart rate variability and blood pressure changes, in headache-free migraineurs (n = 17) and control subjects (n = 22). RESULTS: Levels of high-frequency power, reflecting vagal activity, were lower in migraineurs at baseline but increased after tooth clenching whereas in controls they returned to baseline (P < 0.05, mixed model analysis). In multivariate regression model, the presence of migraine predicted the baseline levels of low- and high-frequency power and sympathovagal balance, and the post-test increase in high-frequency power, with the attack frequency and side of headache as the modifiers of the measured changes in migraineurs. The painful signs of temporomandibular disorders, found in clinical oral examination, enhanced both maximal changes in RR intervals and post-test vagal responses to tooth clenching only in migraineurs. CONCLUSION: The enhanced post-clenching vagal activation may represent a marker of the augmented trigeminocardiac reflex to stimulation of trigeminal area, sensitised in migraineurs. Our results support an involvement of autonomic mechanisms in migraine pathophysiology and are interesting in terms of interactions between migraine and masticatory disorders, elucidating one potential way how masticatory disorders may aggravate migraine.

Determinants of serum 25-hydroxyvitamin D concentration in Finnish children: the Physical Activity and Nutrition in Children (PANIC) study.

We studied vitamin D intake, serum 25-hydroxyvitamin D (S-25(OH)D) concentration, determinants of S-25(OH)D and risk factors for S-25(OH)D <50 nmol/l in a population sample of Finnish children. We studied 184 girls and 190 boys aged 6-8 years, analysed S-25(OH)D by chemiluminescence immunoassay and assessed diet quality using 4-d food records and other lifestyle factors by questionnaires. We analysed the determinants of S-25(OH)D using linear regression and risk factors for S-25(OH)D <50 nmol/l using logistic regression. Mean dietary intake of vitamin D was 5·9 (sd 2·1) µg/d. Altogether, 40·8 % of children used no vitamin D supplements. Of all children, 82·4 % did not meet the recommended total vitamin D intake of 10 µg/d. Milk fortified with vitamin D was the main dietary source of vitamin D, providing 48·7 % of daily intake. S-25(OH)D was <50 nmol/l in 19·5 % of children. Consumption of milk products was the main determinant of S-25(OH)D in all children (standardised regression coefficient ß=0·262; P<0·001), girls (ß=0·214; P=0·009) and boys (ß=0·257; P=0·003) in multivariable models. Vitamin D intake from supplements (ß=0·171; P=0·035) and age (ß=-0·198; P=0·015) were associated with S-25(OH)D in girls. Children who drank ≥450 g/d of milk, spent ≥2·2 h/d in physical activity, had ≥13·1 h/d of daylight time or were examined in autumn had reduced risk for S-25(OH)D <50 nmol/l. Insufficient vitamin D intake was common among Finnish children, one-fifth of whom had S-25(OH)D <50 nmol/l. More attention should be paid to the sufficient intake of vitamin D from food and supplements, especially among children who do not use fortified milk products.

Finger skin temperatures in 8- to 11-year-old children: determinants including physical characteristics and seasonal variation. The Physical Activity and Nutrition in Children (PANIC) Study.

PURPOSE: The fingertip skin temperature (FST) reflects skin blood flow, and FST measurement has been suggested for the investigation of vascular responses. As a limitation, the multifactorial nature and the seasonal variation in measured values have been earlier described in adults but not in children. In the present study, we identify the modifiers of FST in a population sample of Finnish children. METHODS: FST was measured in children (age range 8-11 years, n = 432) with infrared thermometer, and its possible determinants including the subjects' physical characteristics and seasonal variables, such as daylight time and outdoor temperature, were identified. RESULTS: In univariate regression models, FST was dependent on the sex, age and anthropometric characteristics of the children with the higher body fat content-related variables and a lower surface area-to-mass ratio as strongest single modifiers of FST. There was interaction between sex and puberty with FST. In addition, FST was directly related to daylight time and outdoor temperature although the children had stayed inside for at least 2 h before the measurements. The FST values were lowest in the winter and highest in the summer. In multivariate regression model, main determinants of FST were a higher body fat percentage (standardized regression coefficient ß = 0.472; p < 0.001), male sex (ß = 0.291; p < 0.001) and longer daylight time (0.226; p < 0.001). CONCLUSIONS: Altogether, complex effects of body composition and sex with the confounding effect of seasonal variation may complicate the use of FST as a tool to study the vascular function in children.

Are the infrared thermography findings skin temperature-dependent? a study on neck pain patients.

BACKGROUND: Skin temperature (Tsk) disorders have been proposed as sign of impaired innervation in several conditions, but the influence of different factors on the infrared thermography (IRT) findings remains unclear. METHODS: The relations between the Tsk and δT (side-to-side temperature difference) values, and influence of age, gender, anthropometric characteristics and pain intensity on those values were analysed in non-specific neck pain (NP) patients (n = 91) using mixed model analysis. IRT findings were also compared in subgroups of NP patients: with cold (CHNPP, n = 21) or warm hands (WHNPP, n = 56) and healthy controls, with cold (CHC, n = 11) or warm hands (WHC, n = 19). Also, the stability of δT values in CHNPP was examined. RESULTS: Only the area of measurement and the actual Tsk influenced the δT values. CHNPP demonstrated higher δT values in distal parts, compared with WHNPP and controls, but those values vanished when their hands turned warm. δT values in CHNPP were related to the pain intensity. The findings of WHNPP and WHC did not differ. CONCLUSION: Our results suggest that the δT values as signs of impaired Tsk regulation are dynamic and better detectable in cold skin. The results underline the need of caution in interpretation of IRT findings.

Temporomandibular-disorder-related pain as a predictor of severe headaches.

OBJECTIVE: The current study aimed to investigate the association of temporomandibular disorders (TMD)-related pain with the presence of migraine or tension-type headaches (TTH) over a follow-up period of 11 years. METHODS: Data sets from Finnish national health surveys, the Health 2000 Survey (baseline), and the Health 2011 Survey (follow-up) were utilized. Study participants are undergoing clinical TMD examination at baseline and answering questions related to the presence of migraine and TTH at follow-up were included in the study (n = 530). For analyses, the study sample was divided into two data sets: One with those excluded suffering from migraine at baseline (Data set I, n = 345), and the other excluding those having TTH at baseline (Data set II, n = 464). RESULTS: Based on logistic regression modelling, no consistent association between TMD-related pain and the presence of migraine was observed, although jTMD associated with elevated estimates for migraine. However, participants with muscle-related TMD pain (mTMD) at baseline had markedly higher odds for having TTH at follow-up than participants without mTMD at baseline (OR 2.1, 95% CI 1.2-3.8). Joint-related TMD pain (jTMD) at baseline was inversely associated with the presence of TTH at follow-up (OR 0.4, 95% CI 0.1-1.3). CONCLUSION: Contrasting patterns of the associations of TMD-related pain with different severe headaches point towards a more thorough and systematic research approach are needed to understand the mechanisms behind these associations.

Association Between Temporomandibular Disorders Pain and Migraine: Results of the Health 2000 Survey.

AIMS: To study the possible associations of various clinically assessed painful signs of temporomandibular disorders (TMD) with the presence of migraine using a large population-based dataset. METHODS: The data were taken from the nationally representative Health 2000 Survey (BRIF8901). The sample consisted of 5,876 adults (age range 30 to 97 years, mean ± standard deviation 52.5 ± 14.8), 5,378 nonmigraineurs and 498 migraineurs. The study participants answered questions concerning migraine presence, migraine frequency, and migraine medication consumption during a home interview. They also underwent a clinical TMD examination. RESULTS: Based on the multivariate regression models, painful muscular TMD, but not joint-related TMD, was associated with the presence of migraine (odds ratio [OR] = 1.58; 95% confidence interval [CI] = 1.23 to 2.04; P < .01). Migraine with TMD was associated with increased migraine frequency (daily or a few attacks within a week) (OR = 1.93; 95% CI = 1.27 to 2.93; P < .01) and higher migraine medication consumption (OR = 2.37; 95% CI = 1.43 to 3.92; P < .01). CONCLUSION: According to the results of this study, muscle-related TMD pain is associated with the presence of migraine. Additionally, migraine along with painful TMD signs is associated with increased migraine frequency and migraine medication consumption.

Reproducibility of infrared thermography measurements in healthy individuals.

The aim of this study was to investigate the reproducibility of skin surface infrared thermography (IRT) measurements and determine the factors influencing the variability of the measured values. While IRT has been widely utilized in different clinical conditions, there are few available data on the values of the skin temperature patterns of healthy subjects and their reproducibility. We recorded the whole body skin temperatures of sixteen healthy young men with two observers on two consecutive days. The results were compared using intra-class correlations analyses (ICC). The inter-examiner reproducibility of the IRT measurements was high: mean ICC 0.88 (0.73-0.99). The day-to-day stability of thermal patterns varied depending on the measured area: it was high in the core and poor in distal areas. The reproducibility of the side-to-side temperature differences (deltaT) was moderately good between the two observers (mean ICC 0.68) but it was reduced with time, especially in the extremities, mean ICC 0.4 (-0.01-0.83). The results suggest that the IRT technique may represent an objective quantifiable indicator of autonomic disturbances although there are considerable temporal variations in the measured values which are due to both technical factors such as equipment accuracy, measurement environment and technique, and physiological variability of the blood flow, and these factors should be taken into account.

Tooth Clenching Induces Abnormal Cerebrovascular Responses in Migraineurs.

Prevalence of masticatory parafunctions, such as tooth clenching and grinding, is higher among migraineurs than non-migraineurs, and masticatory dysfunctions may aggravate migraine. Migraine predisposes to cerebrovascular disturbances, possibly due to impaired autonomic vasoregulation, and sensitization of the trigeminovascular system. The relationships between clenching, migraine, and cerebral circulation are poorly understood. We used Near-Infrared Spectroscopy to investigate bilateral relative oxy- (%Δ[O2Hb]), deoxy- (%Δ[HHb]), and total (%Δ[tHb]) hemoglobin concentration changes in prefrontal cortex induced by maximal tooth clenching in twelve headache-free migraineurs and fourteen control subjects. From the start of the test, migraineurs showed a greater relative increase in right-side %Δ[HHb] than controls, who showed varying reactions, and right-side increase in %Δ[tHb] was also greater in migraineurs (p < 0.001 and p < 0.05, respectively, time-group interactions, Linear mixed models). With multivariate regression model, migraine predicted the magnitude of maximal blood pressure increases, associated in migraineurs with mood scores and an intensity of both headache and painful signs of temporomandibular disorders (pTMD). Although changes in circulatory parameters predicted maximal NIRS responses, the between-group differences in the right-side NIRS findings remained significant after adjusting them for systolic blood pressure and heart rate. A family history of migraine, reported by all migraineurs and four controls, also predicted maximal increases in both %Δ[HHb] and %Δ[tHb]. Presence of pTMD, revealed in clinical oral examination in eight migraineurs and eight controls, was related to maximal %Δ[HHb] increase only in controls. To conclude, the greater prefrontal right-side increases in cerebral %Δ[HHb] and %Δ[tHb] may reflect disturbance of the tooth clenching-related cerebral (de)oxygenation based on impaired reactivity and abnormal microcirculation processes in migraineurs. This finding may have an impact in migraine pathophysiology and help to explain the deleterious effect of masticatory dysfunctions in migraine patients. However, the role of tooth clenching as a migraine trigger calls for further studies.

Effectiveness of traditional bone setting in chronic neck pain: randomized clinical trial.

OBJECTIVE: This study evaluates the effectiveness of traditional bone setting (TBS) in chronic neck pain (cNP) compared with conventional physiotherapy (PT) and massage (M). METHODS: This was a randomized clinical trial. Working-aged employed subjects with cNP (n = 105; 37 men and 68 women; mean age, 41.5 years) were randomized into TBS, PT, and M groups. Follow-up times were 1, 6, and 12 months after the treatments. Neck pain intensity (visual analog scale), perceived disability (Neck Disability Index [NDI]), and neck spine mobility measurements were used as outcomes. Global assessment was evaluated by the subjects (scale from -1 to +10). Data were analyzed using time (pre and post) by group (TBS, PT and M), 2- way analysis of variance for repeated measures. RESULTS: Neck pain decreased and NDI scores improved in all groups 1 month after the treatment (P < .001). The improvement of NDI and persons' satisfaction were significantly better after TBS. Neck spine mobility in rotation movements tended to improve significantly better and the frons-knee distance improved more after TBS. One year later, both NDI and neck pain were significantly better after TBS than in reference groups. A significant improvement was reported by 40% to 45.5% of subjects in the PT and M groups and by 68.6% in the TBS group. Bone setters' ability to communicate and to interact with patients was evaluated significantly higher. In the TBS group, the number of sick days was minimal as was the use of painkillers during 1-year follow-up compared to that in the reference groups. CONCLUSIONS: Traditional bone setting, which is a soft manual mobilization technique focusing on the muscles, joints, and ligaments, appears to be effective in cNP. Two thirds of subjects experienced it as beneficial, and it seems to be able to improve disability and pain in patients with cNP. Subjective and partially objective benefits of TBS were found in those patients more than after other interventions, and the effects lasted at least for 1 year.

Dynamic surface electromyographic responses in chronic low back pain treated by traditional bone setting and conventional physical therapy.

OBJECTIVE: This study compared the dynamic surface electromyographic (EMG) activities of back muscles and pain before and after traditional bone setting and physical therapy. METHODS: This study was a prospective clinical trial that compared surface EMG dynamic activities after traditional bone setting and physical therapy. Sixty-one patients (mean age, 41 years) with nonspecific low back pain were randomized into two subgroups by treatment. The patients underwent a dynamic EMG evaluation for which they were asked to stand and then bend forward as far as possible, stay fully flexed, and return to standing. A flexion-relaxation ratio was calculated by comparing maximal EMG activity while flexing with the average EMG activity in full flexion. Concentric (maximal EMG activity during extension) and eccentric (maximal EMG activity during flexion) ratios were also used in the analyses. RESULTS: Disability, depression, and visual analog scale scores decreased significantly after both treatments. The concentric ratio increased statistically in both groups after the treatments. The study failed to show a significant association between experienced back pain and EMG parameters. CONCLUSIONS: Both treatments seem to have a positive influence on back muscle function by improving muscle symmetry; however, the treatments had no effect on the flexion-relaxation phenomenon after 1 month. Active back exercise at home together with rehabilitation treatments might be effective and improve function for patients with chronic low back pain.

Plantar infrared thermography measurements and low back pain intensity.

OBJECTIVE: To study the skin temperature disorders in low back pain (LBP) patients compared with reference persons without LBP and to evaluate the relationship between pain intensity and other clinical signs and temperature abnormalities. METHODS: Sixty-five patients with unilateral chronic LBP with or without referred nonradicular leg pain (29 men and 36 women; age range, 30-51 years) and 20 reference persons without LBP (7 men and 13 women; age range, 30-49 years) participated in this study. The pain level was recorded by the use of a visual analog scale (0-100). Questionnaires and a series of spinal mobility tests (the modified Schober, straight leg-raising test, finger-floor distance, side bending) were used. Thermographic images of the low back area and legs (anterior, lateral, and posterior surfaces and the plantar surfaces of feet) were taken with an infrared video camera. RESULTS: The temperature changes in the plantar surface correlated with LBP intensity. The pain levels differed in the groups with the different types of temperature changes. There were significant lower extremity regional skin temperature alterations (at least 1 regional interside difference more than 0.3 degrees C) in most cases both in LBP patients and in reference persons, but plantar interside temperature difference was significantly higher in LBP patients. CONCLUSION: Temperature changes of the plantar surface seem to be connected with LBP intensity. Temperature measurements may be useful as an adjunctive physiological test in the evaluation and documentation of autonomic dysfunction in LBP patients.

High scrotal temperatures and chairs in the pathophysiology of poor semen quality.

AIM:: The purpose of the present study was to investigate the temperature and humidity of the scrotal skin during sitting on commonly used chairs in relation to body mass index. MATERIALS AND METHODS:: Six different chairs were studied, and 8 men participated in the study. In addition to traditional sensors also infrared photography was used in recordings. RESULTS:: Statistically highly significant increase up to 3 degrees C was recorded when subjects were sitting on commonly used chairs already in 20min. When the subjects were sitting on the saddle chair no increase of scrotal skin temperature or humidity was observed indicating good ventilation due to open hip and knee angles. Body mass index correlated with the scrotal skin temperature, when the subjects were sitting on the conventional cushioned office chair, but not when sitting on the saddle chair. Chairs which increase the scrotal temperature may have contributed to the decrease of semen quality and quantity reported during the last decades in sedentary societies.

Sympathetic pathology evidenced by hand thermal anomalies in carpal tunnel syndrome.

OBJECTIVE: To clarify sympathetic pathology in carpal tunnel syndrome and the usefulness of digital infrared thermography as a diagnostic aid. MATERIAL AND METHODS: 38 clinically diagnosed carpal tunnel syndrome hands from 30 patients (confirmed by the standard nerve conduction studies) and 41 hands from 22 healthy volunteers (the hands having current finger inflammation were excluded) were studied. A series of hand infrared photos of each subject were taken and stored by using the technique of digital infrared thermography. We studied the infrared pictures and measured the temperatures of finger tips from digit 1 (D1) to digit 5 (D5), the center point of thenar (Th) and hypothenar eminences (Ht), then we calculated the temperature differences (absolute values) between each two of the 7 points, and median index (MI): (D1-D2)+(D2-D3)+(D1-D3). The means of D2 and Th (MD2+Th), D5 and Ht (MD5+Ht) were also calculated. RESULTS: The results showed that the temperatures of median nerve distribution area in the hands were highly significantly different (Th-Ht, p < 0.001, MI, p < 0.001) between carpal tunnel syndrome (CTS) and the control group. The differences between the median and ulnar nerve distribution area were also highly significantly different in CTS hands (MD2+Th compared to MD5+Ht, p < 0.01). The sensitivity and specificity of digital infrared thermography were 84 and 91%, respectively. CONCLUSION: Digital infrared thermography suggests sympathetic neural pathology in carpal tunnel syndrome. It may also be useful as an additional non-invasive tool in the diagnosis of CTS especially in the early stage.

Sensory and sympathetic disorders in chronic non-specific neck pain.

The signs of sympathetic and sensory nerve-related disorders are not widely investigated in chronic nonspecific neck pain (NNP) patients. Thus, we performed skin temperature (Tsk), evaporation and touch threshold (TT) measurements to reveal possible dysfunctions at the fingertips of NNP patients (n=60) compared with healthy controls (n=11). Neck pain intensity was the main modifier of Tsk, and age the main modifier of TT in a multivariate model. On comparisons of the subgroups of NNP patients with unilateral (n=26) and bilateral (n=34) symptoms and controls, TT differed and Tsk tended to differ, the unilateral pain patients being found to demonstrate higher TT values on both sides. Interrelations between the measured parameters were found in the controls, but not in the patients. The NNP patients exhibited signs of functional impairment of innervation reflected in changes in tactile sensitivity and vasoactive sympathetic function. These changes may be based on both central and peripheral mechanisms, which possibly differ in patients with unilateral and bilateral symptoms.

Computer use related upper limb musculoskeletal (ComRULM) disorders.

Computer use has progressed fast in recent years. The symptoms and signs caused by repetitive computer use that is characterized by neck, shoulder, elbow, wrist and hand pain, paresthesia, and numbness can be called 'Computer Related Upper Limb Musculoskeletal (ComRULM) disorders'. Publications of recent 20 years have been reviewed. These disorders are usually multifactorial processes, caused by occupational, personal and social factors. Some suggestions concerning the diagnostics, procedures of prevention, and treatment options have been discussed. Further studies on 'ComRULM disorders' are necessary.

Acral coldness in migraineurs.

In search for new biomarkers of vascular disturbances accompanying migraine, we compared the facial and hand skin temperatures in 41 women, including 12 migraine patients during the headache-free period and 29 healthy controls. Compared to the controls, the acral skin temperatures were lower in migraineurs, especially in those with right-sided headache. Our findings suggest that migraine is associated with a peripheral coldness possibly due to abnormal autonomic vascular control. The cold nose and hands may represent easily assessable biomarkers of these disorders.

Nitroglycerin-induced changes in facial skin temperature: 'cold nose' as a predictor of headache?

Nitroglycerin (NTG) often induces headaches when used to treat cardiac diseases. Such property of NTG has been widely used in modelling of migraine-like headaches. However, background reasons, predisposing to the development of NTG-headache, are less studied. The main aim of our study was to find, using NTG model, easily accessible markers of the vascular changes associated with headache. Because changes in the blood flow alter the local skin temperature (Tsk), we studied the relationship between the regional changes in the facial Tsk and NTG-induced headaches. Tsk was measured with infrared thermography in 11 healthy women during 3 h after sublingual NTG administration. NTG caused headache in five women, and four of them were the first-degree relatives of migraine patients. Notably, before NTG administration, subjects in the headache group had lower Tsk values, especially in the nose area, than women in the pain-free group (n = 6). NTG-induced headache was associated with a long-lasting increase of Tsk over the baseline. In sharp contrast, in the pain-free group, the Tsk reduced and returned rapidly to the baseline. Thus, the low baseline level and greater increase of regional Tsk correlated with the incidence of headache that supports a role of greater vascular changes in headache happening on the basis of the dissimilarities in vascular tone. An easily accessible phenomenon of 'cold nose' may indicate background vascular dysfunctions in individuals with predisposition to headache. Facial infrared thermography, coupled with NTG administration, suggests a novel temporally controlled approach for non-invasive investigation of vascular processes accompanying headaches.