Association of chronotype and timing of interferon injection with severity of IFNβ-induced flu-like syndrome in Multiple sclerosis (MS) patients.

Time of interferon injection was significantly associated with FLS score, with higher FLS score following evening injection. However, no significant relationship was found between the FLS score and the patient's chronotype. It is recommended that further studies assessing circadian rhythm using laboratory tests such as melatonin measurement need to be undertaken to investigate the association of circadian rhythm with post-interferon injection FLS.