Alterations in cardiovascular autonomic function tests in idiopathic hyperhidrosis

Disentangling the phenotypic patterns of hypertension and chronic hypotension

OBJECTIVE

2017 blood pressure (BP) categories focus on cardiac risk. We hypothesize that studying the balance between mechanisms that increase or decrease BP across the medical phenome will lead to new insights. We devised a classifier that uses BP measures to assign individuals to mutually exclusive categories centered in the upper (Htn), lower (Hotn) and middle (Naf) zones of the BP spectrum; and examined the epidemiologic and phenotypic patterns of these BP-categories.

METHODS

We classified a cohort of 832,560 deidentified electronic health records by BP-category; compared the frequency of BP-categories and four subtypes of Htn and Hotn by sex and age-decade; visualized the distributions of systolic, diastolic, mean arterial and pulse pressures stratified by BP-category; and ran Phenome-wide Association Studies (PheWAS) for Htn and Hotn. We paired knowledgebases for hypertension and hypotension and computed aggregate knowledgebase status (KB-status) indicating known associations. We assessed alignment of PheWAS results with KB-status for phecodes in the knowledgebase, and paired PheWAS correlations with KB-status to surface phenotypic patterns.

RESULTS

BP-categories represent distinct distributions within the multimodal distributions of systolic and diastolic pressure. They are centered in the upper, lower, and middle zones of mean arterial pressure and provide a different signal than pulse pressure. For phecodes in the knowledgebase, 85% of positive correlations align with KB-status. Phenotypic patterns for Htn and Hotn overlap for several phecodes and are separate for others. Our analysis suggests five candidates for hypothesis testing research, two where the prevalence of the association with Htn or Hotn may be under appreciated, three where mechanisms that increase and decrease blood pressure may be affecting one another's expression.

CONCLUSION

PairedPheWAS methods may open a phenome-wide path to disentangling hypertension and chronic hypotension. Our classifier provides a starting point for assigning individuals to BP-categories representing the upper, lower, and middle zones of the BP spectrum. 4.7 % of individuals matching 2017 BP categories for normal, elevated BP or isolated hypertension, have diastolic pressure < 60. Research is needed to fine-tune the classifier, provide external validation, evaluate the clinical significance of diastolic pressure < 60, and test the candidate hypotheses.

Heart rate variability as a potential diagnostic tool to predict compensatory hyperhidrosis after sympathectomy in patients with primary focal hyperhidrosis

Background

Primary focal hyperhidrosis (PFH) is associated with autonomic nervous activity, and studies investigating this association in patients with PFH are very important. Heart rate variability (HRV) is a simple and noninvasive electrocardiographic test showing activity and balance in the autonomic nervous system, which consists of sympathetic and parasympathetic components. The aims of this study are to investigate associations between autonomic nervous activity and hyperhidrosis characteristics using HRV and to investigate the association between HRV findings and compensatory hyperhidrosis (CH) after sympathectomy.

Methods

From March 2017 to March 2020, 105 subjects with PFH who underwent preoperative HRV tests and sympathectomy were analyzed. All subjects underwent bilateral thoracoscopic sympathectomy. T2 sympathectomy was conducted for craniofacial hyperhidrosis, and T3 sympathectomy was conducted for palmar hyperhidrosis. The following HRV parameters chosen to investigate the association between hyperhidrosis and autonomic nervous activity were measured by time and frequency domain spectral analysis: (I) time domain: standard deviation of normal-to-normal interval (SDNN) and square root of mean squared differences of successive normal-to-normal intervals (RMSSD), (II) frequency domain: total power (TP) of power spectral density, very low frequency (VLF), low frequency (LF), and high frequency (HF). HRV parameters were analyzed according to hyperhidrosis type (craniofacial vs. palmar type), sweat reduction, and CH after sympathectomy. In addition, the independent HRV parameters influencing CH after sympathectomy were investigated with multivariate analysis.

Results

Craniofacial hyperhidrosis was significantly more prevalent in the old age group (P<0.001). Sweat reduction after sympathectomy was significantly more prominent in palmar hyperhidrosis (P=0.037), and CH after sympathectomy was more prominent in craniofacial hyperhidrosis (P<0.001). Palmar type patients exhibited significantly larger SDNN, RMSSD, TP, LF, and HF than craniofacial type patients (all P<0.001). There were no significant differences in any HRV parameters according to sweat reduction after sympathectomy. Low-degree CH was associated with significantly larger SDNN, RMSSD, TP, LF, and HF than high-degree CH (P<0.001, P<0.001, P=0.002, P=0.001, and P<0.001, respectively). Multivariate analysis showed that HF and age group were associated with CH after sympathectomy (P=0.007 and P=0.010, respectively).

Conclusions

This study shows that HRV can provide useful insight into the pathophysiology of PFH and enhance preoperative risk stratification of CH. Large-scale, prospective studies are required to determine the predictive value of HRV in patients at risk for subsequent CH after sympathectomy.

Heart Rate Variability Assessment and Its Application for Autonomic Function Evaluation in Patients with Hyperhidrosis

BACKGROUND

Pathophysiology mechanism of primary focal hyperhidrosis (PFHH) is controversial. Heart rate variability (HRV) could explain if there is a systemic component present. We aimed to investigate the functions of the autonomic nervous system in patients diagnosed with PFHH compared to controls using the analysis of HRV in the domains of time, frequency, and nonlinearity, as well as analysis of the recurrence plots (RPs).

METHODS

We selected 34 patients with PFHH (29.4 ± 10.2 years) and 34 controls (29.2 ± 9.6 years) for HRV analysis. Heart beats were recorded with Polar RS800CX monitor (20 min, at rest, in supine position), and RR intervals were analyzed with Kubios Premium HRV software. RPs were constructed with Visual Recurrence Analysis software. Statistical analysis included unpaired t test (p < 0.05).

RESULTS

Our results showed that HRV parameters in the 3 domains evaluated did not show any differences between the groups. The same was observed with RPs.

CONCLUSIONS

The findings suggest that PFHH, from the pathophysiological point of view, may be caused by peripheral involvement of the sympathetic nervous system (glandular level or nerve terminals), as there was no difference between the groups studied. More specific studies should help elucidate this issue.

Personality features and vulnerability to stress: a case study on hyperhidrosis

By using the Rorschach test, self-reports, and psychophysiological measures, we investigated thoroughly the psychological functioning in a hyperhidrotic case. Erica, a young female with hyperhidrosis, was assessed in three times at one-week distance. First, specific tools assessing potential psychological and affective distress, and the Rorschach test were administered. About one week later, Electrodermal Activity was recorded during the exposure to a mild laboratory stress-inducing task. Finally, a magnetic resonance imaging exam was performed in order to exclude medical conditions/neurological alterations for potential physiological anomalies. Erica tends to avoid living in the moment and prefers to experience close relationships in her inner world where she can rehearse the future and imagine different contexts and social situations without risks and embarrassment. She reports high capacities to perform goaldirected behaviors and clarity of emotions only in absence of stressful situations. The study has the merit to be the first to combine Rorschach data with physiological data in order to investigate the psychological functioning in a hyperhidrotic case.

A new method for evaluation of the autonomic nervous system in patients with idiopathic hyperhidrosis: systolic blood pressure and heart rate recovery after graded exercise

BACKGROUND

Idiopathic hyperhidrosis (IH) is characterized by excessive and uncontrolled production of sweat, mainly localized to the soles, palms, axillae and craniofacial area. Although IH is a disease concerning the autonomic nervous system, it is not clear yet whether this dysfunction is local or systemic.

OBJECTIVE

To evaluate the autonomic control of cardiovascular system by measuring values of heart rate recovery (HRR) and systolic blood pressure recovery (SBPR) obtained at various time intervals after maximal graded exercise treadmill testing in patients with IH compared with controls.

METHODS

The study population comprised 36 patients with IH (20 men, 16 women; mean age 25 ± 7 years) and 36 healthy controls (HCs) (12 men, 24 women; mean age 27 ± 5 years). All patients were selected from young, nonobese and healthy sedentary individuals.

RESULTS

Peak HR values reached in patients with IH were significantly higher compared with the HC group (P < 0.001). The obtained HRR values at minutes 3, 4 and 5 were significantly lower in the IH than the HC group [57 ± 16 vs. 64 ± 9 (P = 0.03); 61 ± 14 vs. 68 ± 9 (P = 0.03); 64 ± 12 vs. 70 ± 7 (P < 0.01)]. In addition, calculated mean values for SBPR1 and SBPR2 were > 1 in patients with IH (1.04 ± 0.15 vs. 0.98 ± 0.08 and 1.0 ± 0.12 vs. 0.94 ± 0.06, respectively) and these were statistically significant compared with the HC group (P = 0.04 and P = 0.03, respectively).

CONCLUSIONS

The significantly impaired SBPR and decreased HRR values we observed in patients with IH may indicate that the autonomic dysfunction in IH is a systemic disorder with cardiovascular effects, rather than a merely local disease. Both HRR and SBPR values may provide additional information about predicting adverse cardiovascular events in the future even in apparently healthy young patients with IH.

Syringomyelia, limb hypertrophy and sympathetic overactivity: a rare association

A 32-year-old man presented with uniform enlargement of right upper limb for 6 years. Examination revealed painful disorganised elbow joint along with sensory impairment in the affected limb with weakness of small muscles. The patient was given empirical antileprotic therapy from outside without any benefit. Ultrasonography showed pan-hypertrophic nature of local tissues. Although axonal type of sensorimotor neuropathy involving right ulnar and median nerve was detected in nerve conduction velocity study, biopsy of the same failed to confirm any axonal degeneration or evidence of leprosy. Considering the nature of sensory abnormality MRI of cervical spine was done which revealed a syrinx extending from C3 till D2. Tests for vasomotor tone showed positive results on the affected limb. Syringomyelia can rarely give rise to pan-hypertrophy of limb due to sympathetic overactivity, which is infrequently reported in literatures and deficient in logical grounds.