Exploring determinants of progression in Parkinson's disease. Is there a difference among Jewish ethnic groups?. Issue 3 (March 2015) - Orlev, Y.
Abstract Introduction Parkinson's disease (PD) displays an individually variable rate of progression, of which the underlying mechanisms are largely unknown, but may involve genetic factors. In this study, we aimed to explore the effect of ethnic origin on PD progression rate in Israeli Jews, as expressed by time from onset until reaching Hoehn and Yahr stage 3 (HY3). Methods Consecutive patients with PD followed bi-annually at the Movement Disorders Institute at Sheba Medical Center, were included. Demographic data and clinical information, including age at PD onset (AO), H&Y staging, and family history of PD, were collected. Ethnicity was determined based on the parents' origin and was categorized as Ashkenazi Jews (AJ), Yemenite Jews (YJ), North African Jews (NAJ) and Oriental Jews (OJ) excluding YJ. Associations between the above variables and the time to HY3 were determined using Cox proportional hazards model. Survival curves were derived from the model. Results Of 707 patients [430 males, AJ: 458, YJ: 37, NAJ: 75 and OJ: 137] included in the analysis, 343 had reached HY3. In a multivariate analysis, a longer time to HY3 was significantly associated with a younger AO (HR = 1.07, p < 0.001). YJ showed a significantly shorter time to HY3 compared to AJ and OJ, but not compared to NAJ. Time to HY3 was significantly shorter for NAJ than for OJ. Conclusion Jewish PD patients of Yemenite and North African origin may have a more rapid progression of PD, compared to those of Ashkenazi and Oriental origin, suggesting distinctive genetic influences.