Author Of 1 Presentation
P0838 - Autonomic dysfunction in patients with relapsing-remitting multiple sclerosis treated with different oral disease modifying therapies – a pilot study (ID 1454)
Abstract
Background
Autonomic dysfunction is common among patients with multiple sclerosis (MS) and can contribute to significant disability. However, there are limited data concerning the influence of disease modifying therapies (DMT) on autonomic dysfunction in MS.
Objectives
The aim of this pilot study was to evaluate cardiovascular autonomic function in relapsing-remitting MS (RRMS) patients treated with two different oral DMTs – dimethyl fumarate (DMF) and fingolimod (FTY) – using standard autonomic tests.
Methods
In 8 patients without signs of recent clinical relapse and 8 age and gender matched healthy persons (26.9±2.9 vs 29.1±7.0 years, p=0.42; 7 females in each subgroup, p=1.00), we continuously monitored heart rate (HR), blood pressure (BP) and respiration during supine rest, deep breathing, Valsalva maneuver and head-up tilt. The tests were repeated in patients after initiation of DMF or FTY, with median interval of 9 (7-17) weeks. Six patients started DMF (5 treatment-naïve and 1 switched from interferon beta-1a s.c.). Two patients previously treated with 2 other DMTs (one with interferon beta-1b s.c. and glatiramer acetate and another with interferon beta-1a i.m. and 2 natalizumab infusions) initiated FTY.
Results
Median EDSS was 1.69±1.00 and median time from first MS symptoms was 58.4 months. Clinical autonomic symptoms, such as bradycardia, flushing or gastrointestinal disturbances occurred in 5 patients (62.5%) after DMF or FTY initiation. Before DMT, mean and diastolic BP responses to tilt were significantly smaller in patients than in controls (change from supine baseline by -1.2±2.5 vs 6.0±5.9%, p=0.007 and 0.2±6.2 vs 9.6±8.9%, p=0.03, respectively). Furthermore, prior to treatment, orthostatic hypotension was present in 50% of patients (in 3 from DMF and 1 from FTY group) and none of controls (χ2=5.33, p=0.02). Initiation of oral DMT did not significantly change autonomic variables, however, there was a tendency to lower HR during tilt following DMF (84.6±9.8 vs 80.8±7.6 bpm, p=0.08). Moreover, after DMT initiation, orthostatic hypotension was observed in both FTY patients but only in 1 out of 6 DMF patients (p=0.22). Clinical autonomic symptoms did not correlate with HR responses to orthostatic stress in patients (p>0.1).
Conclusions
Patients with RRMS demonstrated reduced sympathetic responses to orthostatic stress. However, DMF or FTY did not significantly change cardiovascular autonomic function within several weeks of therapy.