MSA-C is the predominant clinical phenotype of MSA in Japan: Analysis of 142 patients with probable MSA

Abstract

We investigated the clinical features and mode of disease progression in 142 patients with probable multiple system atrophy (MSA) according to the Consensus Criteria. The subjects included 84 men and 58 women with a mean age at onset of 58.2 ± 7.1 years (range: 38-79 years). Cerebellar signs were detected in 87.3% of these patients at the time of initial examination, and were found in 95.1% of them at latest follow-up. MSA-C was diagnosed in 83.8% of the patients at their first examination.Parkinsonism was initially detected in 28.9% of the patients, increasing to 51.4% at the latest follow-up. Among all of the subjects, only 16.2% were classified as having MSA-P on initial examination. At the latest follow-up, parkinsonian features had become predominant over cerebellar features in 24.6% of the 65 patients with MSA-C who were followed for more than 3 years. Although parkinsonism usually masked the signs of cerebellar involvement in MSA-C patients, none of the patients with MSA-P at an early stage showed predominance of cerebellar features at the latest follow-up.Parkinsonism is the predominant feature of MSA among Western patients, even at an early stage, but this study showed that cerebellar deficits are the main feature in Japanese patients. This difference of disease manifestations between ethnic groups suggests that genetic factors may influence the clinical phenotype of MSA.

Evidence for α-synuclein prions causing multiple system atrophy in humans with parkinsonism

“…For the majority of the MSA patients, parkinsonism rather than cerebellar symptoms dominated the clinical presentation. Parkinsonism was consistent with the origin of the patient population, as MSA-P is known to be more common in Western countries (16), whereas MSA-C is more frequent in Asian countries (17). The mean age of onset of disease in this MSA patient population was 59 ± 9 y, consistent with previous reports (18).…”

Epidemiology of Multiple System Atrophy in Hokkaido, the Northernmost Island of Japan

“…In this study, the MSA-C predominance in Japan that had been reported in previous studies was confirmed [5,6]. On the other hand, some epidemiological reports from Europe and the United States have shown MSA-P predominance [13,14].…”

“…This epidemiological difference has been confirmed by other studies in each region [6,7]. The difference between MSA-C and MSA-P is the rate of motor symptom progression [8].…”

Comparison of Different Symptom Assessment Scales for Multiple System Atrophy

“…The patients in this study were a good representation of the Asian and Japanese MSA population and were consistent with the previous studies [35][36][37]. Our study patients were in the relatively early stages of MSA and consequently had good ADL, but the average onset age was slightly high.…”