A complex interplay between autonomic symptoms and symptoms of depression, anxiety, and stress.

BACKGROUND: We evaluated the influence of symptoms of depression, anxiety, and stress on the results of COMPASS-31 in a large population of people referred to the head-up tilt test (HUTT) and healthy controls (HC). METHODS: Nine hundred fifty-nine consecutive patients referred to HUTT and 518 HC were enrolled. All participants completed Composite Autonomic Symptom Score-31 (COMPASS-31). Stress symptoms were evaluated by Depression, Anxiety, and Stress-21 (DASS-21) questionnaire. We corrected the result of the COMPASS-31 with the independent predictors in order to improve the specificity of the test. RESULTS: In both patients and HC, COMPASS-31 was higher in participants with depression, anxiety, and stress symptoms (all p < 0.001). In a multivariable linear regression analysis, HC was negative, while female sex and symptoms of depression, anxiety, and stress were independent positive predictors of COMPASS-31. In HC, COMPASS-31 had a median of 7.913, and this value differentiated between HC and patients with a high sensitivity of 87% and low specificity of 50%. In order to adjust the value of COMPASS-31 with the parameters that were significant in the multivariable linear regression model, we calculated the new corrected COMAPSS-31 (cCOMPASS-31), which had comparable sensitivity of 77%, but an increased specificity of 73%. CONCLUSION: This study has shown that symptoms of depression, anxiety, and/or stress worsen the perceived severity of autonomic symptoms in people with symptoms of orthostatic intolerance and healthy population. cCOMPASS-31 is a valuable tool that can help clinicians in discerning the true autonomic background of patients' complaints.

Sudomotor dysfunction in people with neuromyelitis optica spectrum disorders.

BACKGROUND AND PURPOSE: The aim was to determine the extent of sudomotor dysfunction in people with neuromyelitis optica spectrum disorder (pwNMOSD) and to compare findings with a historical cohort of people with relapsing-remitting multiple sclerosis (pwRRMS). METHODS: Forty-eight pwNMOSD were enrolled from four clinical centers. All participants completed the Composite Autonomic Symptom Score 31 to screen for symptoms of sudomotor dysfunction. Sudomotor function was assessed using the quantitative sudomotor axon reflex test. The results were compared with a historical cohort of 35 pwRRMS matched for age, sex and disease duration. RESULTS: Symptoms of sudomotor dysfunction, defined by a score in the Composite Autonomic Symptom Score 31 secretomotor domain >0, were present in 26 (54%) of pwNMOSD. The quantitative sudomotor axon reflex test confirmed a sudomotor dysfunction in 25 (52.1%) of pwNMOSD; in 14 of them (29.2%) sudomotor dysfunction was moderate or severe. No difference was observed between pwNMOSD and pwRRMS in any of the studied parameters. However, symptomatic sudomotor dysfunction was more frequent in pwNMOSD (n = 8, 22.9%) compared to pwRRMS (n = 1, 3%; p = 0.028). In a multivariable logistic regression analysis, statistically significant predictors for symptomatic sudomotor failure were age and diagnosis of neuromyelitis optica spectrum disorder. CONCLUSIONS: Sudomotor dysfunction is common in pwNMOSD and more often symptomatic compared to pwRRMS.

Comparison of pain-provoked versus standard 40-min tilt table test for the conformation of vasovagal syncope.

BACKGROUND: Tilt table test represents a valuable diagnostic method in assessing patients with transient loss of consciousness and confirming the diagnosis of vasovagal syncope. However, the test lacks standardization, and various protocols exist in different centers. The aim of this study was to compare the difference in sensitivity and time-to-syncope of tilt table test with a painful stimulus provocation compared to standard test with no provocation. METHODS: This was a prospective study that included consecutive patients diagnosed with vasovagal syncope who were referred for tilt table testing. Patients were randomly assigned to two groups: group 1 with pain provocation after the first 10 min of upright position and group 2 with no provocation with further 30 min of tilt in both groups. RESULTS: In group 1, 66 (78.6%) patients developed syncope while in group 2, 35 (44.3%) patients had syncope (p < 0.001). This represents an increase of 34.3% in TTT sensitivity with the application of painful provocation. According to results of the Cox regression, the hazard for developing syncope after the 10th min of the tilt for group 2 was 0.275 of the hazard of group 1 (95% C.I. 0.170-0.444, p < 0.001). CONCLUSION: Pain provocation is a useful method for increasing sensitivity and shortening the duration of tilt table testing.

Autonomic dysfunction in people with neuromyelitis optica spectrum disorders.

AIMS: To determine the difference in autonomic symptom burden measured with the Composite Autonomic System Score-31 (COMPASS-31) and presence of objective dysautonomia in people with neuromyelitis optica spectrum disorders (pwNMOSD) compared to people with multiple sclerosis (pwMS). DESIGN/METHODS: Twenty pwNMOSD and 20 pwMS, matched for age, sex, and disease duration, were enrolled. All patients completed the COMPASS-31. The quantification of cardiovascular autonomic dysfunction (CAD) was made using the two indices of the Composite Autonomic Scoring Scale (CASS): adrenergic index (AI) and cardiovagal index (CI). RESULTS: In all pwNMOSD, COMPASS-31 was >0. Sympathetic dysfunction was present in 8 (40%), parasympathetic dysfunction in 10 (50%), and orthostatic hypotension in 6 (30%) pwNMOSD. This group of patients had higher frequency and level on the pupillomotor domain of the COMPASS-31 compared to pwMS (p = 0.048 and p = 0.006, respectively). A binary logistic regression model showed that drop in diastolic blood pressure (dBP) during tilt-table test and normal function of autonomic nervous system, defined as AI = 0 and CI = 0, were independent predictors of pwNMOSD (p = 0.042 and p = 0.029, respectively). If CAD was present, it was significantly worse in pwNMOSD compared to pwMS (p = 0.003). CONCLUSION: Significant proportion of pwNMOSD experience dysautonomia, which seems to be different from dysautonomia observed in pwMS.

The incidence of postural orthostatic tachycardia syndrome in the population of Zagreb, Croatia.

AIM: To estimate the incidence of postural orthostatic tachycardia syndrome (POTS) in the population of Zagreb, Croatia, and to determine the patients' demographic and clinical characteristics. METHODS: From 2012-2017, we identified patients with POTS by a retrospective analysis of medical records at University Hospital Center Zagreb. Crude incidence rates were directly standardized by age according to the European and World Standard Population. RESULTS: Out of 385 patients with suspected POTS, 23 had a definitive POTS diagnosis. The annual incidence ranged from 3.3 to 14.8 per 1000000 for both sexes combined. The highest incidence rates were in the age groups 18-29 and 30-39 years, with female predominance. The mean age at diagnosis was 30.7 years (standard deviation ±9.2, range 18-52). The median duration of symptoms at diagnosis was 7.5 months (range 3-180 months). Regarding associated comorbidities, two patients had chronic gastritis and one patient had each of the following: epilepsy, prior subarachnoid hemorrhage, anxiety, mitral insufficiency, obstructive sleep apnea, hypothyreosis, and irritable bowel syndrome. In patients not fulfilling the criteria for POTS, the most common alternative diagnoses were autonomic dysfunction due to multiple sclerosis in 22, anxiety disorder in 17, epilepsy in 16, and orthostatic tachycardia due to deconditioning in 13 patients. CONCLUSION: The data obtained in this study can be used to optimize disease surveillance in population, comprehensive assessment of disease burden, and organization of health care services.

Performance of the COMPASS-31 questionnaire with regard to autonomic nervous system testing results and medication use: a prospective study in a real-life setting.

The aim of this study was to investigate the performance of the Composite Autonomic System Score-31 (COMPASS-31) questionnaire in a real-life setting in consecutive patients referred to the laboratory for objective testing of the autonomic nervous system (ANS), with the hypothesis that COMPASS-31 results differ depending on medications and findings of the tilt table test results. One hundred seventy-one consecutive patients (125 females, mean age 41.5 ± 19.3) referred for testing of the ANS were enrolled. Before testing, all patients completed the recently validated Croatian version of COMPASS-31. The following data were systematically collected for all patients: age, sex, diagnoses, and medications. Results of COMPASS-31 were significantly higher in patients taking medications with a known influence on the ANS (p < 0.001). Patients with postural orthostatic tachycardia had significantly higher orthostatic intolerance and vasomotor domains of COMPASS-31 (p = 0.048 and p = 0.022, respectively). Patients with a cardiovagal score ≥ 1 had a significantly higher vasomotor domain of COMPASS-31 compared to patients with normal results of ANS tests (p = 0.030). These findings suggest the COMPASS-31 might be a valuable screening tool for autonomic dysfunctions, as it is associated with impaired ANS tests, but usage of medications that modify the ANS should always be taken into account.

Association of Autonomic Nervous System Abnormalities on Head-Up Tilt Table Test with Joint Hypermobility.

AIM: The aim of this study was to investigate the association of autonomic nervous system abnormalities on head-up tilt table test (HUTT) with generalized joint hypermobility, expressed by Beighton score (BS). METHODS: This was a prospective study that included 115 consecutive patients (91 females; mean age 34.35 ± 14.11) referred either for the HUTT or testing of the cardiovascular autonomic reflexes together with HUTT. Generalized joint hypermobility was evaluated according to the BS system after which HUTT was performed. Clinically significant BS was considered if ≥4. RESULTS: Fifteen patients (15.1%) had BS ≥4. Results of the HUTT were normal in 58 (50.4%) patients and in 57 (49.6%) patient HUTT was abnormal. Fifteen (13.0%) patients fulfilled criteria for orthostatic hypotension, 30 (26.1%) for reflex syncope and 21 (18.3%) for postural orthostatic tachycardia syndrome. Patients with pathological findings on HUTT had significantly higher BS compared to patients with normal HUTT (median 1 vs. 0, p = 0.001). There was a significant association between participants with BS ≥4 and pathological HUTT (χ[1] = 6.392, p = 0.011). Results of the multivariate regression analysis revealed that increase in the BS is associated with the increased likelihood of HUTT pathology (Exp[B] 1.44, 95% CI 1.084-1.922, p = 0.012), while increase in age is associated with lower risk of HUTT pathology (Exp[B] 0.968, 95% CI 0.939-0.998, p = 0.036). CONCLUSION: There is an association between autonomic nervous system abnormalities on HUTT test and generalized joint hypermobility.

Validation and cross-cultural adaptation of the COMPASS-31 in Croatian and Serbian patients with multiple sclerosis.

AIM: To validate and cross-culturally adapt Croatian and Serbian versions of composite autonomic symptom score-31 (COMPASS-31) for the detection of dysautonomia in patients with multiple sclerosis (MS). METHODS: A total of 179 patients, 67 with clinically isolated syndrome (CIS) and 112 with MS, completed the COMPASS-31 at two MS centers in Zagreb and Belgrade between April 1 and October 31, 2016. Demographic and clinical data including age, gender, MS phenotypes, and the Expanded Disability Status Scale (EDSS) score were collected. RESULTS: The Cronbach's alpha coefficient of COMPASS-31 total score was 0.844 for the Croatian MS sample and 0.779 for the Serbian MS sample. A joint analysis yielded Cronbach's alpha coefficients ranging from 0.394 to 0.796, with values in four domains higher than 0.700. In Croatian and Serbian samples and the total study sample, the Cronbach's alpha coefficient of COMPASS-31 was 0.785. Reproducibility measured by intra-class correlation coefficient (ICC) was acceptable (ICC=0.795). With regard to the clinical validity, significant correlation was found between EDSS and the COMPASS-31 total score (P<0.001). Furthermore, significant differences between MS phenotypes were detected for bladder and gastrointestinal domains and for the COMPASS-31 total score (PP<0.001, P=0.005, and P=0.027, respectively). Finally, significant differences between MS phenotypes in patients with score >0, which implies the existence of at least one of the symptoms investigated in each domain, were detected for secretomotor and bladder domains (P=0.015 and PP<0.001, respectively). CONCLUSION: COMPASS-31 represents a valid and acceptable self-assessment instrument for the detection of dysautonomia in MS patients.

Sympathetic cardiovascular and sudomotor functions are frequently affected in early multiple sclerosis.

OBJECTIVE: The aim of this study was to determine the prevalence of autonomic dysfunction using the composite autonomic scoring scale (CASS) and heart rate variability (HRV) in patients with clinically isolated syndrome (CIS) and to correlate autonomic dysfunction with other measures of MS disease activity. METHODS: CASS, HRV and plasma catecholamines during supine and tilted phase were performed in 104 CIS patients. MRI findings were analyzed for total number of lesions and the presence of brainstem and cervical spinal cord lesions. RESULTS: Autonomic dysfunction (CASS >1) was present in 59.8 % of patients, parasympathetic dysfunction in 5 %, sympathetic in 42.6 % and sudomotor in 32.7 % of patients. Patients with autonomic dysfunction on CASS had lower level of norepinephrine in the supine position compared to patients without autonomic dysfunction (1.06 ± 0.53 vs. 1.37 ± 0.86, p = 0.048). The CASS score showed positive correlation with s-HF (r = 0.226, p = 0.031), s-SDNN (r = 0.221, p = 0.035), t-HF (r = 0.225, p = 0.032), and t-HFnu (r = 0.216, p = 0.04), and a negative correlation with t-LF/HF (r = -0.218, p = 0.038). More patients with MRI brainstem lesions had a positive adrenergic index (p = 0.038). Patients with MRI brainstem lesions also had a lower t-SDNN (26.2 ± 14.2 vs. 32 ± 13.3, p = 0.036) and a lower t-LF (median 415.0 vs. 575.5, p = 0.018) compared to patients without these lesions. Patients with adrenergic index ≥1 had a significantly higher standing heart rate compared to patients with an adrenergic index of 0 (96 ± 13.5 vs. 90 ± 12, p = 0.032). CONCLUSION: Autonomic (primarily sympathetic) dysfunction is present in a large proportion of early MS patients and it seems to be related to brainstem involvement.

Blood flow velocity changes in anterior cerebral arteries during cognitive tasks performance.

OBJECTIVE: Transcranial Doppler sonography (TCD) enables monitoring of blood flow velocities (BFVs) in basal cerebral arteries during different cognitive tasks performance with great temporal resolution. So far, BFVs changes during mental activity were monitored primarily in middle cerebral arteries (MCAs) and little is known about these changes in anterior cerebral arteries (ACAs). AIM: To determine the effect of different cognitive tasks performance on BFV changes and hemispheric dominance in ACAs and to assess the most suitable activation test for monitoring of BFV changes in ACAs. METHODS: Fourteen right-handed, healthy subjects aged 20-26 were included in the study. BFVs in both ACAs were recorded simultaneously during performance of cognitive tasks designed to activate frontal lobes: phonemic verbal fluency test (pVFT), Stroop tests and Trail Making Tests (TMTs). RESULTS: A statistically significant BFV increase was recorded in both ACAs during performance of all cognitive tasks. Statistically significant right ACA dominance was found during performance of pVFT and TMTB. The most significant BFV increase was obtained during performance of TMTB. CONCLUSION: Our result addressed cognitive tests with great activation potential for monitoring of ACAs that might be used in distinguishing of healthy individuals and patients with neurovascular or neurodegenerative diseases.

Hemodynamic monitoring of middle cerebral arteries during cognitive tasks performance.

AIM: The aim of this study was to obtain temporal pattern and hemispheric dominance of blood flow velocity (BFV) changes and to assess suitability of different cognitive tasks for monitoring of BFV changes in the middle cerebral arteries (MCA). METHODS: BFV were recorded simultaneously in MCA during performance of phonemic verbal fluency test (pVFT), Trail Making Tests A and B (TMTA and TMTB) and Stroop tests in 14 healthy, right-handed volunteers aged 20-26 years. RESULTS: A significant increase of BFV in both MCA was obtained during performance of all cognitive tasks. Statistically significant lateralization was found during performance of Stroop test with incongruent stimuli, while TMTB was found to have the best activation potential for MCA. CONCLUSION: Our findings specify TMTB as the most suitable cognitive test for monitoring of BFV in MCA.

Characteristics and predictors of sexual dysfunction in men with multiple sclerosis.

PURPOSE: To validate and culturally adapt the Sexual Health Inventory for Men (IIEF-5) and the Premature Ejaculation Diagnostic Tool (PEDT), to compare the frequency and severity of erectile dysfunction (ED) and premature ejaculation (PE) in male individuals with MS (mwMS) in comparison with healthy controls (HC) and to investigate predictors of the severity of ED and PE in mwMS. METHODS: 216 consecutive mwMS and 37 HC completed IIEF-5 and PEDT. Additionally, 114 mwMS completed the Modified Fatigue Impact Scale (MFIS), Beck Depression Inventory (BDI-2), Composite Autonomic System Score-31 (COMPASS-31), and the 5-level EQ-5D questionnaire. RESULTS: The test-retest reliability was satisfactory for both questionnaires, with acceptable reliability for both questionnaires. mwMS scored less on IIEF-5 compared to HC (23, IQR 18.25-25 vs 24, IQR 20.25-25, p = 0.028). ED was present in 39.4 % of mwMS and 27.8 % of HC (p = 0.198). Definite PE was present in 12.1 %, and possible PE in 7.8 % of mwMS; and 5.6 % and 11.1 % of HC respectively (p = 0.496). An increase in EDSS was a positive predictor (Exp(B) 1.455, 95 %CI 1.135-1.886, p = 0.003) and the presence of cremasteric reflex was a negative predictor (Exp(B) 0.381, 95 %CI 0.183-0.790, p = 0.010) for the presence of ED. For the PE, disease duration was the only positive predictor in a univariable logistic regression (Exp(B) 1.084, 95 %CI 1.019-1.153, p = 0.070). CONCLUSION: SD is frequent in mwMS with EDSS being a positive and the presence of cremasteric reflex a negative predictor of ED and disease duration a positive predictor of PE symptoms.

Short pain-provoked head-up tilt test for the confirmation of vasovagal syncope.

We investigated a short pain-provoked head-up tilt (PP-HUT) and the Calgary Syncope Symptom Score in a group of patients with clinically diagnosed vasovagal syncope and group of neurological patients without transient loss of consciousness. We included 127 consecutive patients who were investigated in our laboratory. The group 1 included 56 patients who after appropriate investigations were diagnosed with vasovagal syncope. The group 2 included 70 neurological patients without transient loss of consciousness. The subjects were tilted to 70° for a maximum period of 10 min or until symptoms occurred. If there were no symptoms after initial 10 min, a painful stimulus with the insertion of 0.7 mm needle into the dorsum of hand subcutaneously for 30 s was performed with the patient in the tilted for further 5 min. Calgary Syncope Symptom Score was calculated for all patients. In the group 1, significantly higher number of patients had positive results on PP-HUT (36 vs. 6 patients, respectively; p < 0,001). There was no difference in the presence of orthostatic hypotension (8 vs. 15 patients, respectively; p = 0.36) or postural orthostatic tachycardia syndrome (3 vs. 1 patient, respectively; p = 0.32) between groups. PP-HUT had sensitivity of 65.9 % (95 % CI 0.49-0.79) and specificity of 89.7 % (95 % CI 0.75-0.97). The CSSS had sensitivity of 58.5 % (95 % CI 0.42-0.73) and specificity of 46.1 % (95 % CI 0.30-0.63). PP-HUT has a higher diagnostic rate than the CSSS and provides a rapid alternative to conventional methods.

Impact of the autonomic dysfunction on the quality of life in people with NMOSD and MS: An international cross-sectional study.

BACKGROUND: A substantial autonomic nervous system (ANS) dysfunction has been described in multiple sclerosis (MS) and recently, also in neuromyelitis optica spectrum disorder (NMOSD). The prevalence of ANS symptoms contributes to the chronic symptom burden in both diseases. The aim of our study was to assess ANS dysfunction in people with (pw) NMOSD and MS, using the Composite Autonomic Symptom Score-31 (COMPASS-31), and additionally, to evaluate if ANS dysfunction have impact on the quality of life of these patients. METHODS: We conducted cross-sectional study at three national referral neurological clinics in Serbia, Croatia, and Montenegro. A total of 180 consecutive subjects, 80 pwNMOSD and 100 pwMS, followed-up at these clinics, were enrolled in the study. Subjects included in the study completed: the validated versions of the COMPASS-31 and the Multiple Sclerosis Quality of Life-54 (MSQoL-54), and the Beck Depression Inventory (BDI). RESULTS: This study demonstrated that the total COMPASS-31 score > 0.0, implicating the presence of ANS dysfunction, was detected in almost all NMOSD and MS study participants tested (80/80, and 97/100, respectively). Our findings showed that autonomic symptom burden was statistically significantly correlated with decreased quality of life, in both NMOSD and MS cohorts. The independent predictors of the better quality of life in pwNMOSD were lower autonomic burden, particularly the absence of the orthostatic intolerance (p = 0.005), along with lower EDSS and BDI score (p ≤ 0.001). Similarly, in pwMS, independent predictors were EDSS, BDI, orthostatic intolerance, and the total COMPASS-31 (p ≤ 0.001). CONCLUSION: Our study demonstrated that a significant proportion of persons with both NMOSD and MS have considerable dysautonomic symptom burden which is correlated with the decreased quality of life. Further investigations are warranted in order to optimize treatment interventions in MS and NMOSD.

Blood pressure variability is altered in secondary progressive multiple sclerosis but not in patients with a clinically isolated syndrome.

OBJECTIVES: To investigate differences in beat-to-beat systolic blood pressure variability (SBPV) in people with secondary progressive MS (pwSPMS), clinically isolated syndrome (pwCIS) and healthy controls (HC). METHODS: This retrospective case-control study included 46 pwSPMS, 46 pwCIS and 44 HC. A semi-automated software made with MATLAB R2019b (The MathWorks, Inc.) was used for the evaluation of SBPV. The frequency domain characteristics observed were the power spectrum in the LF and HF bands and the LF/HF ratio. Data is expressed in absolute power (mmHg2) of LF and HF and ratio (LF/HF) during both supine and tilt-up phases of testing. RESULTS: There were no significant differences in mean systolic (sBP) or diastolic blood pressure (dBP) values during supine and tilt-up phases of testing between groups. During the supine phase of testing LF and LF/HF were significantly lower in the SPMS group (4.17±5.38 and 3.52±2.34, respectively) compared to the CIS (5.42±3.59, p = 0.015 and 5.92±4.63, p = 0.029, respectively) and HC group (6.03±4.55, p = 0.011 and 6.52 ±â€¯5.09, p = 0.010, respectively), while during the tilt-up phase, LF was significantly lower compared to both the CIS and HC group, and HF was significantly lower only compared to the CIS group. CONCLUSION: SBPV is altered in pwSPMS compared to pwCIS and normal controls. Further research in the field of MS related dysautonomia is warranted not only because of its relevance to comorbidities and MS symptoms, but also because of its likely involvement in the pathophysiology of MS.

Short- and long-term effects of siponimod on autonomic nervous system in secondary progressive multiple sclerosis.

OBJECTIVES: The aim of this study was to investigate the short- and long-term effects of siponimod on autonomic nervous system (ANS) function, in people with secondary progressive multiple sclerosis (pwSPMS) METHODS: The following ANS tests were performed in 26 pwSPMS: a 10 min supine resting position, Valsalva maneuver, deep breathing test and a 10 min tilt-up table test. Heart rate variability (HRV) was performed for the 10 min in supine resting position (M0) and for a 3 h period after siponimod treatment initiation (M0s1-6). All ANS tests were repeated after at least 6 months of treatment with siponimod (M6). RESULTS: In all 6 intervals after siponimod ingestion (M0s1-6), standard deviation of NN intervals (SDNN) was higher compared to M0. After 6 months of continuous treatment with siponimod, SDNN was significantly lower compared to M0. At M6, Valsalva ratio and respiratory sinus arrhythmia were lower compared to M0 values (1.510±0.338 vs 1.864±0.456, p=0.003 and 7.969±2.865 vs 13.091±4.687, p<0.001, respectively). Cardiovagal index was significantly higher at M6 compared to M0 (1 (range 0-2) vs 0 (range 0-1), p=0.008, respectively). Active Magnetic Resonance Imaging (MRI) one year prior to starting siponimod was a positive predictor of M6 SDNN and Adrenergic Index (AI) at M0 was a negative predictor of M6 SDNN. CONCLUSION: This study has shown an inverse relationship in short- versus long-term effects of siponimod on ANS function. A shift towards parasympathetic predominance was observed during the first three hours after ingestion, while after 6 or more months of continuous treatment with siponimod, a shift towards sympathetic predominance was observed.

Comparison of baroreflex sensitivity indices with standard tests of autonomic nervous system function.

OBJECTIVE: In order to further evaluate clinical usefulness of α- and ß-adrenergic components of the baroreflex sensitivity (BRS) index, the aim of this study was to compare them to standardized measures of the autonomic dysfunction. METHODS: In 275 participants (mean age 40.57 ± 15.19, range 18 to 89 years, 76.4% females) referred for testing of the autonomic nervous system, α-BRSa, ß-BRSa and BRSv were compared to heart rate (HR) and blood pressure (BP) values, adrenergic and cardiovagal indices of the Composite Autonomic Severity Score (CASS) and heart rate variability (HRV) parameters. RESULTS: α-BRSa showed statistically significant positive correlation with HR in the supine position and negative with the adrenergic index. ß-BRSa showed statistically significant negative correlation with tests for parasympathetic nervous system function. BRSv showed statistically significant negative correlation with all HR and BP parameters and positive with all HRV parameters. In a univariable logistic regression analysis, α-BRSa was a negative predictor (Exp(B) 0.866, 95% CI 0.782-0.959, p = 0.006, respectively) of the pathological adrenergic index. To differentiate between subjects with normal and pathological adrenergic index, the optimal cutoff for α-BRSa was found to be 6.741, which gave a sensitivity of 61.0% and a specificity of 56.0%. CONCLUSION: BRSa indices showed a good correlation with standard measures of ANS function. The most promising test was α-BRSa, which performed well as a α adrenergic receptors mediated sympathetic nervous system marker.

Autonomic nervous system abnormalities predict cardiovascular changes after initiation of siponimod in secondary progressive multiple sclerosis.

OBJECTIVE: The aim of this study was to identify whether autonomic nervous system (ANS) dysfunction identified prior to treatment initiation can predict siponimod related decrease in heart rate (HR) after treatment initiation. METHODS: In 26 people with secondary progressive multiple sclerosis (SPMS) the following ANS testing protocol was applied: 10-min supine resting position, Valsalva maneuver, deep breathing test, 10 min tilt-up table test, 5-min supine resting period, ingestion of siponimod, followed by 180-min supine resting period recordings. Heart rate variability (HRV) parameters were investigated as possible predictors of decrease in HR (ΔHR) after treatment initiation. RESULTS: After treatment initiation, there was a statistically significant drop in HR (71.1 ± 9.2 to 66.3 ± 8.1, p < 0.001) and elevation of systolic blood pressure (sBP) (113.2 ± 12.4 to 117.1 ± 10.8, p = 0.04). Values of the diastolic BP (dBP) followed similar trend as did sBP, however not reaching statistical significance (72.8 ± 9.6 to 74.9 ± 8.3, p = 0.13). In a multivariable regression model, disease duration and standard deviation of NN intervals (SDNN) were identified as independent predictors for ΔHR, where increase in SDNN and longer disease duration predict smaller ΔHR. CONCLUSION: ANS abnormalities may predict cardiovascular abnormalities associated with treatment initiation with siponimod. SIGNIFICANCE: Results of this study may help mitigate risks associated with siponimod treatment.

The Relationship between Autonomic Regulation of Cardiovascular Function and Body Composition.

BACKGROUND: We investigated whether the results of autonomic function tests correlate with body composition and shape in healthy young people. METHODS: We conducted cardiovascular reflex tests (heart rate [HR] and blood pressure [BP] responses to the Valsalva maneuver and HR response to deep breathing) and the tilt table test with 32 subjects (19 males; mean age, 22.1±1.9 years). Participants also completed an anthropometric measurement sequence (weight; height; upper arm, hips, and waist circumference; triceps and subscapular skinfold), bioelectric impedance testing, and hand grip strength measurements. RESULTS: Markers of obesity, other anthropometric measures, functional measures, and the basal metabolic rate (BMR) were significantly positively correlated with systolic BP (SBP) and diastolic BP (DBP) in both the supine and tilted positions. There was a positive correlation between the difference in HR (ΔHR) between the tilt and supine body positions and markers of obesity, the functional marker of dominant handgrip strength, and BMR. Participants with a body mass index (BMI) <25 kg/m2 had significantly lower median values of ΔHR, DBP in the tilt-test, SBP at rest, and SBP in the tilt-test than participants who had a BMI ≥25 kg/m2 (10.55 vs. 21.95 bpm, P=0.003; 77.55 vs. 90.05 mmHg, P=0.045; 113.45 vs. 140.55 mmHg, P=0.013; 117.00 vs. 135.25 mmHg, P=0.006, respectively). Body fat percentage was identified as an independent positive predictor (ß=0.993; 95% confidence interval [CI], 0.070 to 1.916; P=0.036) and body water percentage was an independent negative predictor of tilted SBP (ß=-1.370; 95% CI, -2.634 to 0.106; P=0.035). CONCLUSION: High sympathetic activity, as evaluated by cardiovascular regulation, correlates with a high share of adipose tissue in young healthy persons.

Effect of Food Intake on Hemodynamic Parameters during the Tilt-Table Test in Patients with Postural Orthostatic Tachycardia Syndrome.

BACKGROUND AND PURPOSE: The aim of this study was to determine the effect of food intake on the heart rate (HR) in postural orthostatic tachycardia syndrome (POTS). METHODS: The following five-phase protocol was applied to 41 subjects who had a sustained HR increment of ≥30 beats/min within 10 min of standing in an initial tilt-table test: 1) 10-min supine phase, 2) 10-min 70°-tilted phase, 3) ingestion of 400 mL of Nutridrink Multi Fibre®, 4) 45-min supine phase, and 5) 10-min 70°-tilted phase. Subjects were divided into four groups: A) difference in HR for standing vs. supine (ΔHR) before the meal of ≥30 beats/min (n=13), B) ΔHR <30 beats/min before the meal but ≥30 beats/min after the meal (n=12), and C) ΔHR <30 beats/min both before and after the meal (n=16). Group D consisted of 10 healthy subjects. RESULTS: Before the meal, ΔHR was significantly higher in group A than in all of the other groups, and in group B than in group D (p<0.001). After the meal, ΔHR was significantly higher in groups A and B (p<0.001 and p<0.0001, respectively). When we pooled patients (according to their symptoms) from group A and B into a POTS group and from group C and D into a non-POTS group, an increase in HR of 25 beats/min before the meal had a sensitivity of 92.0% and a specificity of 80.8%. After the meal, an increase in HR of 30 beats/min had a sensitivity of 96.0% and a specificity of 96.2%. CONCLUSIONS: Food intake can significantly alter the results of the tilt-table test and so should be taken into account when diagnosing POTS.