Orthostatic hypotension in Parkinson disease: how much you fall or how low you go?

Abstract

Orthostatic hypotension (OH) is frequent in patients with Parkinson's disease (PD) and can occur with or without symptoms. Pharmacological treatments are effective, but often exacerbate supine hypertension. Guidelines exist for the diagnosis, but not for the treatment of OH. We examined the relationship between blood pressure (BP) and symptoms in a cohort of PD patients with the goal of identifying a hemodynamic target to guide treatment. We measured BP supine and upright (tilt or active standing) and identified the presence or absence of symptomatic OH by using a validated patient-reported outcome questionnaire in 210 patients with PD. We evaluated the usefulness of the 20/10 and 30/15 mmHg diagnostic criteria (systolic/diastolic) to identify symptomatic OH. Fifty percent of the PD patient cohort met criteria for the 20/10 fall and 30% for the 30/15 BP fall. Among the patients who met either OH criteria, the percentage of those with symptoms was small (33% of those with 20/10 and 44% of those with 30/15 mmHg; 16% and 13%, respectively, overall). Symptomatic OH was associated with an upright mean BP below 75 mmHg. A mean standing BP <75 mmHg had a sensitivity of 97% and a specificity of 98% for detecting symptomatic OH. Although the prevalence of OH in PD is high, not all patients have symptoms of organ hypoperfusion. A mean standing BP below 75 mmHg appears to be a useful benchmark when deciding whether the benefits of initiating pharmacological treatment of OH outweigh the risks of exacerbating supine hypertension.

Keywords: autonomic failure; consensus criteria; dysautonomia; mean blood pressure; standing blood pressure; supine hypertension.

© 2015 International Parkinson and Movement Disorder Society.

Figures

Figure 1. Prevalence of orthostatic hypotension

Overall average shows the percentages of symptomatic and global OH according to each of the two criteria. According to age groups, there is a trend toward increased prevalence of global and symptomatic OH with increasing age regardless of the criteria used.

Figure 2. Mean Blood Pressure after 3-min standing in patients with and without orthostatic hypotension and with and without orthostatic symptoms

Patients with symptoms had a significantly lower MBP standing than those with symptoms, regardless of the presence of OH (p<0.001). In the vast majority of patients, symptoms appeared when MBP<75 mmHg (denoted with a horizontal dashed line and shaded area). (60.1±10.5 mmHg vs. 89.5±12.3 mmHg in the 20/10 group; 58.4±10.1 mmHg vs. 90.3±11.1 mmHg in the 30/15 group).

Figure 3. Sensitivity and specificity of different criteria to identify symptomatic orthostatic hypotension

A MBP below 75 mmHg had the best-combined sensitivity (97.2%) and specificity (98.3%) to predict symptomatic orthostatic hypotension in patients with Parkinson disease.