Autonomic Dysfunction In MS

Introduction
Multiple Sclerosis (MS) can cause alterations in Autonomic CardioVascular functioning. Some authors attribute these anomalies detected in MS patients to BrainStem lesions.

Due to the fact that important Autonomic Nuclei are located in this region of the Brain. Other studies, however, have been unable to prove such a relation.

AIMS
The purpose of this study was to analyze whether these alterations had an exclusive relation with the BrainStem lesions that usually appear in the course of this disease.

Patients And Methods
We compared the Spectral Analysis of the Heart Rate Variability (SAHRV) in the frequency domain between a group of 34 patients with MS.

And, another group of 14 patients with Isolated BrainStem Lesions (IBSL) of a non inflammatory origin, which were measured using a 24 hour Holter recording.

Results
Heart rate, very low rates, low rates and the low rate/high rate quotient are significantly higher in the MS group than in the IBSL group.

Even when the former present BrainStem lesions, results in the high rate component, however, depend on the presence of BrainStem lesions in the MS group.

Conclusion
These findings suggest that Autonomic CardioVascular Dysfunction in MS is only related with BrainStem lesions, although we obtained results that confirm the importance of this area in CardioVascular innervation.

CardioVascular Dysfunction (CD) in Multiple Sclerosis (MS) is related to involvement of reflex pathways in the BrainStem.

The battery of CD tests was applied to a group of 40 healthy subjects and 40 patients with MS, divided in 2 subgroups according to the Expanded Disability Status Scale (EDSS).

The tests included:

1. Postural blood pressure changes
   
2. Postural Heart Rate changes
   
3. Heart Rate changes on inspiration/forced expiration
   
4. ECG R-R interval measurement on the Valsalva maneuver

Both groups were subjected to the functional independence scale (FIM). Imaging studies were reviewed and Autonomic Dysfunction at other levels was explored.

The results showed a statistically significant difference (P < 0.05) in all tests when comparing patients to controls.

Tests 1 and 4 had the highest significance, with findings of more severe involvement in patients with a higher EDSS and lower FIM. A correlation was also found between CD and BrainStem lesions on MRI (P < 0.01).

A significant number of MS patients had evidence of CD. Test 1 may be considered a simple marker, in daily clinical practice, to detect subclinical CD. Subclinical CD is a cause of disability in this group of patients.

Twenty patients with active Relapsing/Remitting Multiple Sclerosis (MS) were examined annually for 2 years with a set of Autonomic Function Tests (AFT) consisting of Heart Rate Variability during deep breathing (IE), standing-up, and Ratios of Valsalva manoeuvre (VR).

Disease characteristics, including T₂-weighted Magnetic Resonance Imaging (MRI) of the Brain and the Expanded Disability Status Scale (EDSS) score were documented each year within 1 week of the AFT.

The EDSS score, MRI load lesion and VR did not change significantly over the follow-up period.

The IE and initial Heart Rate on standing during the first 30 s (DeltaHRMAX) showed significant worsening during follow-up. No relationship was found between deterioration of AFT and EDSS score, number of exacerbations, duration of disease, gender, age, size and number of lesions on MRI.

We conclude that patients with active Relapsing/Remitting MS show progression of Autonomic Dysfunction over a relatively short time.

Therefore, in the absence of changes in clinical disability or Brain MRI lesion load, AFT might be useful as a sensitive surrogate outcome measure for demonstrating subclinical change in MS.

Copyright 1999 Lippincott Williams & Wilkins

Sexual Dysfunction affects a large part of patients suffering from Multiple Sclerosis, but some aspects of its clinical presentation and Etiology are not clearly defined yet.

In an unselected sample of 108 patients with definite Multiple Sclerosis we investigated the relationship between symptoms of Sexual Dysfunctioning and Sphincteric Dysfunction, patients' and disease characteristics, Disability and Neurological Impairment, Psychological and Cognitive functioning.

Sexual Dysfunction directly correlated with presence of:

1. Physical Disorders (r=0.37, P=0.0004)
   
2. Low Educational Level (r=0.32, P<0.002)
   
3. Disability (r=0.31, P<0.003)
   
4. Age at Onset of symptoms (r=0.30, P<0.003)
   
5. Sphincteric Dysfunction (r=0.30, P<0.003)
   
6. Age (r=0.30, P<0.004)
   
7. Depression (r=0.29, P<0.005)
   
8. Fatigue (r=0.29, P=0.005)
   
9. Cognitive Deterioration (r=0.26, P<0.01)
   
10. Primary/Progressive Disease (r=0.25, P<0.02)
    
11. Neurological Impairment (r=0.25, P<0.02)
    
12. Marriage (r=0.24, P<0.02)
    
13. Anxiety (r=0. 23, P<0.03)
    
14. Male Gender (r=0.22, P=0.03)
    
15. Bladder Dysfunction (r=0. 29, P<0.04)
    
16. Unemployment (r=0.21, P<0.04).

Sexual Dysfunction correlated inversely with Relapsing/Remitting course of disease (r=-0.31, P<0.002).

No correlation was found between Sexual Dysfunction and Bowel Dysfunction, duration of disease, Secondary/Progressive course of disease, number and frequency of sexual intercourses in the last year, number of partners, number of exacerbations in the last year, number of months since last exacerbation, masturbation, and fertility.

In conclusion, the association between Sexual Dysfunction and Sphincteric Dysfunction indicates a common Etiology corresponding to the frequent involvement of the Spinal Cord in Multiple Sclerosis.

But the concomitant correlation between Sexual Dysfunction and other variables suggests the possible aetiological role of Physical, Psychological and Sociological factors as well.

The objectives of the present study were to test odor identification ability in patients with Multiple Sclerosis (MS) and to examine possible correlations between smell identification test scores and various clinical variables.

We performed a case-control study comparing the Cross Cultural Smell Identification Test scores of 40 patients with definite Multiple Sclerosis with those obtained in 40 age-, sex- and smoking-habit-matched healthy controls.

The Neurological Impairment, the Disability, the Cognitive performances and the Psychological functioning were also assessed.

Patients with Multiple Sclerosis scored significantly poorer than controls on the Cross-Cultural Smell Identification Test (P<0.001). Olfactory function was borderline normal in four (10%) and abnormal in five (12.5%) MS patients, whereas it was normal in all controls (P<0.02).

Significant correlations between the smell identification score and symptoms of Anxiety (r=-0.43, P=0.006), Depression (r=-0.42, P=0. 008) and severity of Neurological Impairment (r=-0.32, P=0.05) were found.

Only two (5%) patients with Multiple Sclerosis reported having episodes of smell loss, suggesting a low level of awareness of this problem. Although smell changes are rarely reported, Olfactory function is impaired in a considerable number of patients with MS.

The observed association between decreased odor identification ability and symptoms of Anxiety and Depression in our patients suggests that Mood and Anxiety Disorders have to be considered in assessing Olfaction in MS patients.

Clearly, smell disturbances deserve greater attention from health professionals and caregivers dealing with such patients.

Autonomic dysfunction causes significant disability in patients with Multiple Sclerosis (MS).

Abnormalities of Bladder, Bowel and Sexual function have been well documented in previous studies but CardioVascular and SudoMotor Autonomic changes have been less frequently reported.

The present study has documented Autonomic symptoms and results of CardioVascular and SudoMotor Autonomic Function Tests in 63 MS patients and correlated these changes with the clinical features of MS.

Autonomic symptoms were common in MS patients, the most common being disorders of Micturition, Impotence, SudoMotor and GastroIntestinal disturbances, which were associated with increased MS severity.

There was no significant association between Autonomic symptoms and abnormalities of Autonomic investigations.

Abnormalities of one or more Autonomic function tests, not including those of Bladder, GastroIntestinal or Sexual Dysfunction, were present in more than one half of the MS patients.

Autonomic Dysfunction, defined as abnormalities in two or more tests, was found in 18% of patients and was associated with increased MS severity. Postural HypoTension was very uncommon.

ParaSympathetic CardioVascular Autonomic abnormalities occurred in 16% of patients and were associated with increased MS severity.

Sympathetic CardioVascular abnormalities were present in 13% of patients and showed no significant association with MS severity.

The Sympathetic Skin Response (SSR) was abnormal in nearly one half of the patients and also showed no significant association with MS severity.

There was a variable and heterogenous pattern of Autonomic test abnormalities found in the MS patients, which were of minor clinical significance except for Postural HypoTension.

CardioVascular and Sudomotor Autonomic abnormalities in MS patients are likely to be due to plaques distributed throughout the BrainStem and Spinal Cord affecting anatomically widespread Autonomic Regulatory Areas and their connections.