Depression and anxiety in multiple sclerosis patients: The role of genetic variability of interleukin 1β

•rs16944TT genotype is a susceptibility factor to the development of psychopathology in MS.•rs16944 polymorphism may be involved in feelings of anxiety in the normal population.•Immune factors could be implicated in the physiological regulation of mood. Mood disorders, as depression and anxiety, are frequent in Multiple Sclerosis (MS) patients. High pro-inflammatory cytokine levels (e.g. IL-1β) have been reported in depressed individuals. We aimed to investigate the role of the rs16944 (IL-1β-511 C>T) polymorphism in the development of anxiety and depression symptoms in a Portuguese cohort of MS patients. 393 MS patients answered the Hospital Anxiety and Depression Scale (HADS) at T1. This questionnaire was reapplied to a subgroup of 175 MS patients approximately three years later (T2). HADS cut-off scores for anxiety and depression were respectively ≥11 and ≥8. At T1, anxiety was found in 106 MS patients (27.0%) and 11 controls (16.7%); whereas depression was identified in 116 (29.5%) MS patients and 9 controls (13.6%). Persistent anxiety and depression were respectively recorded in 12% and 20% of MS patients. The rs16944TT genotype was found to be a susceptibility factor for the occurrence of depression at T1 (OR = 3.16, p=0.002) and the development of persistent depression (OR = 5.63, p=0.003) in MS. Study results support the hypothesis that inflammation is a significant factor in psychopathology development.