Contributions
Abstract: P311
Type: Poster
Abstract Category: Clinical aspects of MS - Epidemiology
Background: Multiple sclerosis (MS) is a chronic disabling neurological disease typically manifest in young adults aged between 20 and 40. Age at the onset of MS is often assigned retrospectively and is based on several factors including patients" recollection of the first neurological symptom and therefore presumably less reliable. In addition, early MS/non-MS symptoms can be assigned mistakenly for another. We investigated accuracy of onset age and the prodromal phase of MS using number of sick leave days in a population-based cohort of MS patients and non-MS controls.
Methods: Clinical and demographic data and number of sickness absence days from MS patients and age, sex and area of residence matched controls were obtained from three Swedish nationwide databases. We employed joinpoint regression models to identify significant deviations in the age-specific trend of sickness absence spells in MS patients at the time of MS onset in relation to the changes in controls.
Results: 10,852 MS patients and 202,976 controls were included. The mean number of age-specific
(18 to 55) sick leave days increased by an average of 0.94 (95%Confidence Intervals (CI): 0.89 to 0.99) in MS patients compared with 0.63 (95%CI: 0.58 to 0.67) in controls. The sharpest increase in the mean number of sick leave days overlapped the recorded onset age, however, in the 30-34 and 35-39 onset age groups sickness absence days in about 41% of individuals started to increase from seven years before the recorded onset age.
Conclusions: Even though recorded onset age in MS is appeared to be of reasonable accuracy, MS patients" general state of health, as measured by number of sickness absence days, started to deteriorate several years before the clinical manifestation of the disease. Investigations of the causes of sickness absence long before recorded onset age might give a clue about the temporal aspects of etiologic or triggering event(s) of MS. Our finding in a real-world setting warrant further observational studies and will inform design of new clinical trials for MS.
Disclosure:
Omid Beiki: nothing to disclose
Ali Manouchehrinia: nothing to disclose
Jan Hillert: JH has received honoraria for serving on advisory boards for Biogen and Novartis and speaker"s fees from BiogenIdec, Merck-Serono, Bayer-Schering, Teva and Sanofi-Aventis. He has served as P.I. for projects, or received unrestricted research support from, Biogen, Merck-Serono, Sanofi-Genzyme and Novartis.
Abstract: P311
Type: Poster
Abstract Category: Clinical aspects of MS - Epidemiology
Background: Multiple sclerosis (MS) is a chronic disabling neurological disease typically manifest in young adults aged between 20 and 40. Age at the onset of MS is often assigned retrospectively and is based on several factors including patients" recollection of the first neurological symptom and therefore presumably less reliable. In addition, early MS/non-MS symptoms can be assigned mistakenly for another. We investigated accuracy of onset age and the prodromal phase of MS using number of sick leave days in a population-based cohort of MS patients and non-MS controls.
Methods: Clinical and demographic data and number of sickness absence days from MS patients and age, sex and area of residence matched controls were obtained from three Swedish nationwide databases. We employed joinpoint regression models to identify significant deviations in the age-specific trend of sickness absence spells in MS patients at the time of MS onset in relation to the changes in controls.
Results: 10,852 MS patients and 202,976 controls were included. The mean number of age-specific
(18 to 55) sick leave days increased by an average of 0.94 (95%Confidence Intervals (CI): 0.89 to 0.99) in MS patients compared with 0.63 (95%CI: 0.58 to 0.67) in controls. The sharpest increase in the mean number of sick leave days overlapped the recorded onset age, however, in the 30-34 and 35-39 onset age groups sickness absence days in about 41% of individuals started to increase from seven years before the recorded onset age.
Conclusions: Even though recorded onset age in MS is appeared to be of reasonable accuracy, MS patients" general state of health, as measured by number of sickness absence days, started to deteriorate several years before the clinical manifestation of the disease. Investigations of the causes of sickness absence long before recorded onset age might give a clue about the temporal aspects of etiologic or triggering event(s) of MS. Our finding in a real-world setting warrant further observational studies and will inform design of new clinical trials for MS.
Disclosure:
Omid Beiki: nothing to disclose
Ali Manouchehrinia: nothing to disclose
Jan Hillert: JH has received honoraria for serving on advisory boards for Biogen and Novartis and speaker"s fees from BiogenIdec, Merck-Serono, Bayer-Schering, Teva and Sanofi-Aventis. He has served as P.I. for projects, or received unrestricted research support from, Biogen, Merck-Serono, Sanofi-Genzyme and Novartis.