Introduction: Psychological troubles are common in multiple sclerosis but their underlying etiology is still controversial.
Methods: The objective of this open, non comparative, multicenter study was to assess changes in global psychological functioning in new multiple sclerosis patients during the first 3 months of treatment with intramuscular interferon beta-1a once weekly (Avonex). This functioning was rated every 4 weeks with the GAF (Global Assessment Functioning) scale. Depression measured on MADRS (Montgomery & Asberg Depression Rating Scale), clinical global impression (CGI) on patients'psychological status and clinical as well as biological tolerance were also assessed every 4 weeks.
Results: Five hundred and ninety-nine patients (71.4 percent women), aged 39.4 years were included. No clinically significant difference in mean GAF score between baseline and the end of the first 3 months of interferon beta-1a IM treatment (main evaluation outcome) was found. Similar results were obtained on MADRS scale.
Conclusion: No clinically significant alteration of global psychological functioning, including symptoms of depression, was observed during the first 3 months of treatment with interferon beta-1a IM.