Sleep Quality In Essential Tremor:a Comparison With Parkinson’s Disease Patients And Normal Controls

Objective:Through the application of the Pittsburgh sleep quality index(PSQI) and the Epworth sleepiness scale(ESS) to investigate the similarities and differences of sleep quality between essential tremor (ET),Parkinson’s disease (PD) patients and normal controls,and to analyze the incidence rate of sleep disorder in ET and its characteristics.Methods:Sleep was assessed using the Pittsburgh sleep quality index and the Epworth sleepiness scale in53ET cases,69PD cases and45normal controls. ET and PD cases were selected from the initial and untreated patients.Normal controls were selected from the frequency-matched by age and gender to ET cases. The incidence rate of sleep disorder and sleep quality was evaluated by the three of sleep test scores.PSQI total scores, incidence rate of sleep disorder and distribution of patients endorsing individual PSQI items were compared between the ET and PD cases.Results:The incidence rates of sleep disorder were69.8%,72.5%and44.4%in ET cases,PD cases and normal controls respectively.The ET cases-PD cases difference was not significant(P=0.749>0.05),and the ET casee-control difference was significant (p=0.002<0.05).There was no significant difference between the ET and PD cases in the distribution of patients endorsing individual PSQI items (P>0.05).The mean±SD ESS score increased from normal controls (5.53±2.78), to ET cases (7.00±3.30), to PD cases (7.61±4.77), test for trend p=0.04<0.05. An ESS score≥10(an indicator of greater than normal levels of daytime sleepiness) was observed in4(8.8%) normal controls, compared to14(24.6%) ET cases and19(27.5%) PD cases (p=0.02when comparing ET to normal controls, and p=0.855when comparing ET to PD cases).Conclusions:Some sleep scores in ET were intermediate between those of PD cases and normal controls,suggesting that a form of sleep dysregulation could be present in ET.It is similar in both incidence rate of sleep disorder and clinical manifestations between ET and PD.Sleep disorder in ET are common, so clinicians should pay attention to it.