The Clinical Heterogeneity Of Orthostatic Hypotension In Patients With Parkinson's Disease

Objective:To investigate the clinical heterogeneity of patients with Parkinson's disease(PD)in terms of orthostatic hypotension(OH),to explore the possible risk factors for OH in PD patients and to improve the diagnosis and treatment of OH.Subjects and Methods:121 patients with PD were enrolled in the Department of Neurology,Qilu Hospital of Shandong University,from January 2016 to December 2017.Blood pressure and corresponding heart rate of all patients were measured both in supine position,and after 1 minutes,3 minutes and 5 minutes of standing position respectively.The basic information,and the clinical data like the course of the disease,the anti-Parkinson disease medication was collected.The clinical subtypes and restless legs syndrome(RLS)was analyzed.The stage of the disease was evaluated using Hoehn-Yahr scale.All patients during the "on" period were assessed by the movement disorder society-sponsored revision of the unified parkinson's disease rating scale(MDS-UDPRS).the scale for outcomes in parkinson's disease for autonomic symptoms(SCOPU-AUT),the rapid eye movement sleep behavior disorder screening questionnaire(RBDSQ),the part one of Orthostatic Hypotension Questionnaire(OHQ_partone).the mini-mental state examination(MMSE).Further,all PD patients with OH(the PD-OH group)were divided into different types based on different characteristics.All data were statistically analyzed using R(3.3.3)software.The difference of clinical information was mainly compared between PD patients with and without OH(PD-OH versus PD-nonOH).The Mann-Whitney U and Fisher's Exact was applied to analyze the similarities and differences in each group.Based on the results of single factor analysis and the Akaike information criterion,Using the Logistic regression analysis,the disease course,bodymassindex(BMI),RBD,RLS,OHQ_partone and MDS.UPDRS_I were chosen as independent variables to calculate the risk factors of OH.Statistical significance was set at P<0.05.Results:1.Among 121 patients with PD,38 PD patients reached the OH criterion and the incidence of OH was 31%.Most of the PD with OH occurred in 3 minutes after standing,accompanied with increased reflexes heart rate.2.There were significant differences between the two group with and without OH(PD-OH versus PD-nonOH)in age,BMI,duration,Hoehn-Yahr stage,RBD,RLS,the first,second,third parts and total scores of MDS.UPDRS,the scores of SCOPA-AUT and OHQ_partone.3.The cluster analysis further verified the results of single factor analysis of variances,but no single variance was found to independently differentiate the PD patients with OH or not.Some patients with OH appeared at the early stage of PD,always together with older age,low BMI,RBD and/or RLS.4.According to the Akaike information criterion,the results of Logistic regression analysis showed that low BMI,RLS,RBD,high MDS.UPDRS_I and OHQ_patone scores were risk factors for OH.5.The decision tree model indicated that 25 of the 48 PD patients had OH when the course of disease was longer than 5.1 years.Then if BMI was less than 20.1,23 among 34 patients developed OH.Further,when MDS.UPDRS_I score of those patients was greater than 12,there were 90%PD patients with OH.The accuracy of the decision tree analysis is 0.82,with the specificity 0.96,and the sensitivity 0.48.Conclusions:1.The incidence of orthostatic hypotension in Parkinson's disease is not uncommon,with 31%in this study.2.Among PD patients,those with OH were significantly older,had lower BMI,more advanced Hoehn&Yahr stage,a longer duration,high score of SCOPA-AUT,MDS-UPDRS.No independent risk factors for OH were found.Various factors with a combined effect increased the risk of OH.3.Although most patients with OH happened in the advanced stage of the disease,some patients with OH occured in the early stage of PD,always accompanied by older age,low BMI,RBD and/or RLS.4.The course of disease,BMI,RLS,RBD,OHQ_partone and MDS.UPDRS_I could better explain the occurrence of OH.5.Those patients with the courses of longer than 5.1 years,BMI less than 20.1,and the MDS.UPDRS part one scores more than 12 were more likely to have OH.For such patients,screening of OH should be routinely performed.