The investigators noted that continuous non-invasive blood pressure monitoring upon standing may aid in the identification of a modifiable risk factor for syncope-related falls in patients with Parkinson disease.
Transient orthostatic hypotension (tOH) is at least as common as classic orthostatic hypotension (cOH) in patients with Parkinson disease, and occurs as an age-dependent phenomenon, according to the findings of a recent study.
All told, the assessment included 173 patients with Parkinson and an age- and gender-matched control group of the same size, and uncovered that tOH occurred in 24% (n = 41) of those with Parkinson compared to 21% (n = 37) of controls (odds ratio [OR], 1.1; 95% CI, 0.6–2.0; P = .759), while cOH occurred in 19% (n = 32) and 0%, respectively, and 12% (n = 20) of those with Parkinson fulfilled OH criteria after a single minute of standing.
Notably, 40% (n = 69) of patients with Parkinson had a history of falls, 29% of which were due to syncope. PD patients with history of orthostatic intolerance and syncope had a more severe systolic BP fall and lower diastolic BP rise upon standing, most pronounced in the first 30 to 60 seconds.
“Transient blood pressure falls when changing to the upright position may be overlooked with bedside blood pressure measurements but contribute to orthostatic intolerance and syncope in Parkinson disease,” the authors, including Alessandra Fanciulli, MD, PhD, department of neurology, Medizinische Universität Innsbruck, wrote in conclusion. “Continuous non-invasive blood pressure monitoring upon standing may help identify a modifiable risk factor for syncope-related falls in parkinsonian patients.”
Pathological blood pressure regulation upon standing was observed in 41% (n = 71)of patients with Parkinson and 21% (n = 37) of controls. After adjustment for the total number of drugs, use of anti-hypotensive, anti-hypertensive and central nervous system-acting drugs other than dopaminergic medications, patients with Parkinson showed an OR of 2.0 (95% CI, 1.2–3.5; P = .013) for any form of orthostatic blood pressure dysregulation.
Fanciulli et al. defined tOH as a systolic blood pressure fall of ≥20 mmHg or diastolic ≥10 mmHg resolving within the 1st minute upon standing, and cOH as a sustained systolic BP fall of ≥20 mmHg or diastolic ≥10 mmHg within 3 minutes upon standing. “In those with Parkinson, we reviewed the medical records of the 6 months preceding and following autonomic testing for a history of falls, syncope, and orthostatic intolerance,” they noted.
When comparing the Parkinson cohort with the age- and gender-matched patients with orthostatic intolerance but a negative neurological history, there were similar frequencies of initial OH (iOH), although delayed orthostatic blood pressure recovery was significantly more frequent in those with Parkinson than in controls (P = .019).
In the 6 months following or prior to cardiovascular autonomic function testing, syncope was documented in 13% (n = 22) of patients with Parkinson, occurring upon standing in all but 2 patients and was associated with falls (P <.001). A history of syncope was present in 17% of the Parkinson group who had an altered blood pressure regulation upon standing and in 10% of those without.
“Performing a standing test under continuous heart rate and blood pressure monitoring may thus help in identifying a modifiable cause of syncope-related falls in patients with a suggestive medical history,” the investigators wrote.
The frequency of syncope did not differ between PD patients diagnosed with tOH versus cOH at cardiovascular autonomic function testing (10% versus 23%, respectively). Upon standing, those with Parkinson and a history of syncope showed lower absolute systolic blood pressure values after 30 seconds (P = .015) and 1 minute (P = .016), as well as more severe systolic blood pressure falls, which were most pronounced after 30 seconds (P <.001) and 1 minute (P = .001) in the upright position.
“To the best of our knowledge, this is the first study specifically investigating tOH in Parkinson,” Fanciulli et al. wrote. “IOH40/20, as defined by the 2018 Guidelines for the Diagnosis and Management of Syncope of the European Society of Cardiology, occurred rarely. The observed frequency of delayed orthostatic blood pressure recovery was also lower than previously reported for the general aging population. Patients with Parkinson mostly showed milder transient orthostatic blood pressure changes, i.e., iOH20/10, but overall, tOH was at least as common as cOH in the present study.”
The group concluded by noting that in light of the frequency and potential impact on Parkinson-related symptoms, including tOH as an outcome measure in interventional trials targeting OH should be recommended.