Detecting factors that influence disease variability in MS patients is crucial to provide novel insights into the etiology of the disease and guide the search for effective therapies. To study the phenotypic variability, well-defined unbiased cohort studies are necessary. The most common and arguably most important variable to be considered as a confounding factor when studying variability of disease course in MS, is age.
To identify determinants that explain phenotypic variability in MS, while eliminating the undesirable effect of age variation between MS patients.
Project Y is an ongoing population-based cross-sectional study of all people with MS born in the Netherlands in 1966. Participants are subjected to extensive examinations of a wide array of potential determinants and outcome measures: functional and static imaging, biomarkers in body fluid, physical and cognitive measurements, and lifestyle factors early and later in life. Age and sex matched controls are included.
As for July 2020, a total of 386 eligible MS patients were identified, of which 31 refused to participate and 86 patients awaiting inclusion. Thirteen patients had passed away prior to study inclusion. Between December 2017 and July 2020, 269 MS patients participated with either a full or partial data collection, together with 125 healthy controls. The total number of identified cases (386) results in a prevalence of at least 1.7/1000 in the birth year 1966.
The first preliminary data of our unique cohort indicate that the previously presumed prevalence of MS in the Netherlands (1/1000) is a serious underestimation of the actual prevalence.