Pre-motor signs of PD are related to SN hyperechogenicity assessed by TCS in an elderly population

Much effort has been put in the identification of risk factors and pre-motor markers for Parkinson's disease (PD). In contrast to many of the pre-motor markers, SN hyperechogenicity (SN+) assessed by transcranial sonography (TCS) has been found to be conclusive for vulnerability for PD. In two centers in Germany 1204 individuals ≥50 years without the diagnosis of PD were recruited and the prevalence and relation of SN+ to a range of pre-motor markers was evaluated. SN+ was detected in 193 (16.0%) of 1204 subjects. Hyposmia (25.4%) was the most frequent sign in the cohort, followed by the occurrence of slight motor deficits. Male gender, positive family history of PD as possible risk factors and the pre-motor markers slight parkinsonian signs, one-sided reduced arm swing, and hyposmia were found to be significantly associated with SN+. The number of subjects who had more than one marker was significantly larger in the SN+ subgroup than in the non-hyperechogenic group (9.2% vs. 2.1%). Most of the discussed markers for PD seem to be unspecific with older age, but related to SN+. Co-occurrence of these markers is more probable in SN+ subjects. These findings may have implications for the design of high-risk cohorts for PD.