title: Prevalence and clinical features of non-motor symptoms of essential tremor in Shanghai rural area.
abstract: OBJECTIVE
  Few studies regarding the epidemiology of essential tremor (ET) and its non-motor symptoms (NMS) have been conducted to date. We thus conducted a door-to-door survey to investigate the ET and its NMS and their clinical manifestations in a rural area of Shanghai, China.
  
  
  METHODS
  We recruited 19,614 residents (≥ 50 years old), living in Malu town, Shanghai. Investigations were divided into two steps. In first step, trained physicians conducted door-to-door surveys and reported probable ET subjects to movement disorder specialists. In the second step, participants with suspected ET had their diagnosis confirmed by movement disorder specialists. We randomly selected 123 subjects from those adults who screened negative for neurological conditions as healthy controls for the study of NMS.
  
  
  RESULTS
  The prevalence of ET in individuals (≥ 50 years old) was 0.306% (PR = 3.06 per 1000). The mini-mental state examination (MMSE) scores were lower in ET patients than in controls (25.81 ± 4.20 vs. 26.63 ± 3.14, P= 0.024). Complaints of restless legs reported by ET patients were significantly higher than those in controls (P < 0.05). In contrast, we did not observe a significant difference for other NMS between ET patients and controls, including olfactory function (P = 0.82), depression (P = 0.94), and rapid eye movement sleep behavior disorder (RBD) (P = 0.71).
  
  
  CONCLUSIONS
  The prevalence of ET in people ≥ 50 years old in a rural area of Shanghai China is low. Prevalence of certain NMSs was higher among participants with ET relative to health controls.
authors.forename: Yiwen
authors.initials: Y
authors.lastname: Wu
authors.forename: Xi
authors.initials: X
authors.lastname: Wang
authors.forename: Cheng
authors.initials: C
authors.lastname: Wang
authors.forename: Qian
authors.initials: Q
authors.lastname: Sun
authors.forename: Ning
authors.initials: N
authors.lastname: Song
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Qianwen
authors.initials: Q
authors.lastname: Jiang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Qiao
authors.forename: Jing
authors.initials: J
authors.lastname: Xu
authors.forename: Liang
authors.initials: L
authors.lastname: Liang
authors.forename: Huidong
authors.initials: H
authors.lastname: Tang
authors.forename: Jianfang
authors.initials: J
authors.lastname: Ma
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
authors.forename: Sheng-Di
authors.initials: SD
authors.lastname: Chen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D003863:Depression / Q000453:epidemiology*; D020329:Essential Tremor / Q000453:epidemiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D000857:Olfaction Disorders / Q000453:epidemiology*; D015995:Prevalence; D020187:REM Sleep Behavior Disorder / Q000453:epidemiology*; D012148:Restless Legs Syndrome / Q000453:epidemiology*; D012424:Rural Population / Q000706:statistics & numerical data*