Month-of-birth-effect in multiple sclerosis in Austria.

BACKGROUND: The month-of-birth-effect (MoBE) describes the finding that multiple sclerosis (MS) patients seem to have been born significantly more frequently in spring, with a rise in May, and significantly less often in autumn and winter with the fewest births in November. OBJECTIVES: To analyse if the MoBE can also be found in the Austrian MS population, and if so, whether the pattern is similar to the reported pattern in Canada, United Kingdom, and some Scandinavian countries. METHODS: The data of 7886 MS patients in Austria were compared to all live births in Austria from 1940 to 2010, that is, 7.256545 data entries of the Austrian birth registry and analysed in detail. RESULTS: Patterns observed in our MS cohort were not different from patterns in the general population, even when stratifying for gender. However, the noticeable and partly significant ups and downs over the examined years did not follow the distinct specific pattern with highest birth rates in spring and lowest birth rates in autumn that has been described previously for countries above the 49th latitude. CONCLUSION: After correcting for month-of-birth patterns in the general Austrian population, there is no evidence for the previously described MoBE in Austrian MS patients.

Detection and kinetics of persistent neutralizing anti-interferon-beta antibodies in patients with multiple sclerosis. Results from the ABIRISK prospective cohort study.

Two validated assays, a bridging ELISA and a luciferase-based bioassay, were compared for detection of anti-drug antibodies (ADA) against interferon-beta (IFN-ß) in patients with multiple sclerosis. Serum samples were tested from patients enrolled in a prospective study of 18 months. In contrast to the ELISA, when IFN-ß-specific rabbit polyclonal and human monoclonal antibodies were tested, the bioassay was the more sensitive to detect IFN-ß ADA in patients' sera. For clinical samples, selection of method of ELISA should be evaluated prior to the use of a multi-tiered approach. A titer threshold value is reported that may be used as a predictor for persistently positive neutralizing ADA.