The influences of cytokines as a possible substrate for the psychological effects of immunomodulation therapy in multiple sclerosis

The impact of drugs for multiple sclerosis on sleep

Although there is a growing literature on the presence of sleep disorders in multiple sclerosis (MS), few studies have specifically addressed the impact of drugs on sleep of these patients. Moreover, even when sleep is considered, quantitative assessment by standardized questionnaires or polysomnography is lacking. The studies that have been done highlight that interferon-beta and some symptomatic medications may affect sleep, thus contributing to fatigue, depression, and poor quality of life; conversely, natalizumab and cannabinoids may improve sleep. Common limitations of the literature reviewed here are small sample size, selection bias, and often a lack of objective outcome measures. Clinicians need to remember to ask about sleep in all MS patients and intervene when appropriate. A systematic approach that takes sleep into account is recommended to enhance recognition and appropriate management of sleep disruption, including disorders related to medication. Consideration of the impact on sleep should also be part of the design of trials of new therapies.

Sleep disturbance and fatigue in mild relapsing remitting multiple sclerosis patients on chronic immunomodulant therapy: an actigraphic study

Background: poor sleep is common in MS and it contributes to fatigue. The β interferons produce systemic effects which may not adapt and may induce fatigue.

Objective: to verify whether subjective poor sleep and fatigue during chronic therapy correspond to reduced sleep efficiency obtained by actigraphy at home.

Methods: 42 ambulatory relapsing remitting MS patients with mild disability were monitored for at least 7 nights. Habitual sleep quality and fatigue were assessed with the MOS sleep measure and the Fatigue Severity Scale. Sleep logs provided daily sleep quality assessments during actigraphy at home. Patients were grouped according to their current treatment: no therapy, glatiramer acetate, IFNβ 3 times a week, and IFNβ once a week.

Results and Conclusion: sleep efficiency was reduced by an average of 5% in 2/3 of the nights following IFNβ injections compared to the other nights, and daily sleep ratings correlated with actigraphy. Patients on glatiramer acetate also showed a lower sleep efficiency than patients without therapy. Actigraphy data were only modestly correlated with MOSsm scores, not with fatigue. Long term adaptation of sleep effects of immunomodulant agents is incomplete and needs to be considered in treatment planning and assessment of sleep in MS.