Postural abnormalities in Asian and Caucasian Parkinson's disease patients: A multicenter study

Introduction: Postural abnormalities (PA) are disabling features of Parkinson's disease (PD). Indirect analyses suggested a higher prevalence of PA among Asian patients compared to Caucasian ones, but no direct comparisons have been performed so far.Methods: An international, multicenter, cross-sectional study was performed in 6 European and Asian movement disorders centers with the aim to clarify differences and similarities of prevalence and characteristics of PA in Asian vs. Caucasian PD patients. Axial PA, encompassing antecollis (AC), camptocormia (CC), and Pisa syndrome (PS), and appendicular PA (appPA) were systematically searched and analysed in consecutive patients. Results: 88 (27%) of 326 PD patients had PA (29.1% in Asians and 24.3% in Caucasians, p: 0.331). Prevalence of axial PA was 23.6% in Asians and 24.3% in Caucasians (p = 0.886), in spite of a longer disease duration among Caucasians, but a longer PA duration among Asians. No differences in prevalence between AC, CC, and PS were found between the two ethnicities. The prevalence of appPA was higher in Asians (p = 0.036), but the regression analysis did not confirm a significant difference related to ethnicity. Considering the whole population, male gender (OR, 4.036; 95% CI, 1.926-8.456; p < 0.005), a longer disease duration (OR, 2.61; 95% CI, 1.024-6.653; p = 0.044), and a higher axial score (OR, 1.242; 95% CI, 1.122-1.375; p < 0.0005) were the factors associated with axial PA. Conclusion: The prevalence of axial PA in PD patients is not influenced by ethnicity. However, Asian PD patients tend to develop PA earlier in the disease course, particularly AC.