Burden of Sensitive Skin Questionnaire and Current Perception Threshold: Use as Diagnostic Tools for Sensitive Skin Syndrome

The assessment of sensitive skin syndrome, characterized by subjective unpleasant sensations, remains a challenge, since there is no international consensus on the best diagnostic tools. This study evaluated the combination of the Burden of Sensitive Skin (BoSS) questionnaire and the current perception threshold as diagnostic tools for sensitive skin syndrome, and the relationship between BoSS and the subjects’ smoking status, phototype and skin type. A total of 100 women completed the BoSS questionnaire, and current perception threshold was measured on the face. The BoSS score was significantly higher in the self-reported sensitive skin group compared with the non-sensitive skin group (25.61 vs 14.05; p < 0.001), and in non-smokers vs smokers (23.00 vs 18.37; p < 0.05). In addition, the current perception threshold values were similar between the sensitive and non-sensitive groups. These results suggest that BoSS is a better diagnostic tool for sensitive skin syndrome than the current perception threshold, and that smokers less frequently have sensitive skin than do non-smokers.

Current perception threshold testing in chronic ankle instability

Background Damage to sensory input is an underlying pathology of chronic ankle instability (CAI). Therefore, it is necessary to evaluate the sensory function of patients with CAI. The present study quantitatively evaluated sensory nerve function in patients with CAI and healthy controls using current perception threshold (CPT) measurements, as well as the influence of sex, age, and body mass index (BMI) on CPT values and the relations between CPT frequencies. Methods Fifty-nine subjects with CAI and 30 healthy controls participated in this study. CPT values at the anterior talofibular ligament region were recorded on the injured and uninjured sides in CAI patients and on both sides in the healthy control group. Between group differences were compared. The influence of sex, age and BMI on CPT values was evaluated. Correlations between different frequencies were also studied. Results There were no significant differences in age, sex, height, weight or BMI between the CAI and healthy control groups. The CPT values did not show a significant difference by sex. The CPT values did not significantly correlate with age or BMI. Compared to the control group, the CAI group had significantly higher CPT values on the injured and uninjured sides under 250-Hz and 5-Hz electrical stimuli; the difference between the groups was significant (p < 0.01), and the effect size were large. No significant difference was observed under 2000-Hz stimuli. There were correlations between CPT values at different frequencies (p < 0.01), especially 250 Hz and 5 Hz. Conclusion The present study revealed increased sensory thresholds in 250-Hz- and 5-Hz-related sensory nerve fibres in the injured and uninjured ankles of patients with CAI. This increase may indicate dysfunction of A-delta and C fibres. Sex, age and BMI did not significantly impact CPT values. There were correlations between CPT values at different frequencies, especially 250 Hz and 5 Hz. Level of evidence Level III, case-control study.

Analysis of the effect of fingertip size for sex differences in current perception thresholds with transcutaneous electrical stimulation in healthy subjects

Objective This study aimed to measure the current perception threshold (CPT) of five fingertips of the left hand in healthy subjects and analyze whether sex differences in perception thresholds are suppressed when adjusting for fingertip size among males and females. Results For fingertips from the thumb to the little finger, the males’ CPT values were 1.03, 0.83, 0.86, 0.86, and 0.88 mA; the females’ results were 0.63, 0.55, 0.54, 0.51, and 0.50 mA. The CPTs were higher in males than in females for every fingertip. Upon adjusting for fingertip length, the log-transformed CPT values were found to have sex differences, except for the index finger: thumb, t(20.05) = 3.493, p = 0.002; middle finger, U(30) = 44.50, p = 0.005; ring finger, t(30) = 55.50, p = 0.018; little finger, U(30) = 30.00, p = 0.001. Similarly, the CPT values, transformed into log values when adjusting for the fingertip area, were found to have sex differences for three fingertips: thumb, t(18) = 2.649, p = 0.016; middle finger, U(20) = 12.00, p = 0.004; ring finger, t(18) = 2.206, p = 0.041. According to this study, sex differences in CPTs were not completely abolished by adjusting for fingertip length or area.

Correlation Between Gut Microbiome Composition and Acute Pain Perception in Young Healthy Male Subjects

Objective Recently, there has been growing interest in the gut–brain axis because it is emerging as a player influencing the health status of the host human. It is a known fact that the gut microbiome (GM) through the gut–brain axis has been implicated in numerous diseases. We previously reported that stool condition was associated with pain perception. Stool consistency and constipation are known to be associated with GM composition. Thus, we imagine that GM composition could influence pain perception. The aim of this study was to investigate the correlations between GM composition and pain perception and psychological states in young healthy male subjects. Subjects A total of 42 healthy young male volunteers completed the present study. Methods The volunteers’ pain perceptions were assessed by pressure pain threshold, current perception threshold, temporal summation of pain, and conditioned pain modulation, and a questionnaire on psychological state was obtained. During the current perception threshold examination, we used 5, 250, and 2,000 Hz to stimulate C, Aδ, and Aβ fibers. In addition, GM composition was evaluated by using 16S rRNA analysis. Results Pressure pain threshold showed a significant and negative correlation with Bacteroidetes phylum, in contrast to a significant and positive correlation with Firmicutes phylum. Current perception threshold of Aδ and Firmicutes phylum showed a significant correlation. There was a negative correlation between anxiety state and Bifidobacterium genus. In contrast, there was no significant correlation between psychological states and pain perceptions. Conclusion The present study showed that acute pain perception was associated with GM composition in young healthy males.

A test-retest reliability study of assessing small cutaneous fibers by measuring current perception threshold with pin electrodes

Background The quantitative measurement of current perception threshold (CPT) has been used as a method to assess the function of nerve fibers in neuropathy diseases. The aim of this study was to assess the test-retest reliability measuring CPT using the circular pin electrodes for assessing the function of cutaneous thin nerve fibers. Methods CPT measurement was repeated on two separate days with at least one-week interval in 55 volunteers. Superficial blood flow (SBF) and skin temperature (ST) were measured on the skin in an around area concentric to the circular pin electrodes after the process of finding CPTs. The coefficient of variation (CV) and intra-class correlation coefficient (ICC) were calculated. The correlation between each two of CPT, SBF increment and ST increment was analyzed. Results No significant differences were found for CPT, SBF and ST between two sessions. SBF was found to be significantly increased after the process of finding CPT. CPT values of males were found to be higher than females. SBF increment was found to be positively correlated with ST increment. The ICC values for CPT, SBF and ST were 0.595, 0.852 and 0.728, respectively. The CV values for CPT, SBF and ST were 25.53%, 12.59% and 1.94%, respectively. Conclusions The reliability of CPT measurement using circular pin electrodes is fair, and need consistence of measurements in longitudinal studies.

References Values for the Current Perception Threshold in the Pharynx Based on a Study of a Healthy Population

Objectives: The application of the current perception threshold (CPT) in the diagnosis of pharyngeal sensory abnormalities has rarely been studied, and there is a lack of reference values for this application. This study established a normal reference range for CPT in the pharynx based on a study of a healthy population. Methods: The CPT values of the palatoglossal arch, posterior 1/3 of the lingual body and hard palate were measured in 60 healthy individuals at 2000, 250, and 5 Hz. The influencing factors were analyzed, and reference values for the CPT were established. Results: There was no correlation between the CPT value and gender. Age was only correlated at 250 Hz level in the hard palate. The CPT values of the palatoglossal arch were 324.95 ± 82.422 at 2000 Hz, 66.90 ± 38.622 at 250 Hz, and 13 ± 14.93 (7.83-22.75) at 5 Hz. The CPT values of the posterior 1/3 of the lingual body were 359.17 ± 76.299 at 2000 Hz, 86.92 ± 35.151 at 250 Hz, and 19 ± 15.73 (13.03-28.75) at 5 Hz. The CPT values of the hard palate were 157.5 ± 61.75 (124-185.75) at 2000 Hz, 57.63 ± 28.785 at 250 Hz, and 22 ± 25.73 (11.03-36.75) at 5 Hz. Conclusions: The CPT values of the pharynx in healthy people were not related to gender. The CPT values of the hard palate for 250 Hz stimulation were related to age, and there were no relationships between the CPT values and age for the other frequencies and loci. We established a normal reference range of CPT values in the pharynx from measurements obtained from healthy populations.

Current Perception Threshold Testing in Chronic Ankle Instability

Background: Damage to sensory input is one of the pathologies underlying chronic ankle instability (CAI). Therefore, it is necessary to evaluate the sensory function of patients with CAI. This study aims to quantitatively evaluate sensory nerve function in patients with CAI and healthy controls using current perception threshold (CPT) measurements.Methods: Fifty-nine subjects with CAI and 30 healthy control individuals participated in this study. CPT values at the anterior talofibular ligament region were tested on the injured and uninjured sides in CAI patients and on a random side in the healthy control group.Results: There were no significant differences in age, gender, height, weight or BMI between the CAI and healthy control groups. The CPT values did not show significant gender differences. The CPT values were not significantly correlated with age or BMI. Compared to the control group (250 Hz: 24.32±9.28, 5 Hz: 6.87±1.56), the CAI group had significantly higher CPT values on the injured (250 Hz: 42.83±28.49, 5 Hz: 23.43±18.53) and uninjured sides (250 Hz: 38.62±19.98, 5 Hz: 18.84±14.21) under 250 Hz and 5 Hz electrical stimuli (p<0.01). No significant difference was observed under 2000 Hz stimuli. There were correlations among CPT values at different frequencies (p<0.01).Conclusion: This study revealed increased sensory thresholds in injured and uninjured ankles of 250 Hz- and 5 Hz-related sensory nerve fibers among patients with CAI. The bilateral change in sensory threshold may indicate a central sensory modulation process.Level of Evidence: Level III, case-control study.