Broñola, Lorness Mae V. MT 632 1F–MT 2nd Shift JournalRationale and Objective of the study The researchers of the journal article described Orthostatic Hypotension (OH) as a decrease in the systolic and diastolic blood pressure resulting from prolonged standing.
The systolic blood pressure was said to decrease in a minimum of 20 mmHg while the decrease of the diastolic blood pressure was at least to be 10 mmHg. In relation to this, the researchers identified that there was no distinct range of orthostatic heart rate (HR)–the heart rate of a person with OH–that will aid the pathologist to identify its relation to the failure of the patient’s autonomic functions. Thus, the researchers identified their objective to clearly propose a specific range of the orthostatic HR of the patient that will help the pathologist in identifying whether the patient has a failure of autonomic functions brought by neurodegenerative synucleinopathies.Methods used The researchers chose 444 patients under autonomic evaluation in the U.
S. Autonomic Disorders Consortium. These patients were evaluated based on a standardized battery test for their autonomic function as well as a neurological evaluation. The standardized test was comprised of: measuring the parasympathetic function of the patients, a test to evaluate their breathing while in the supine position for 300 seconds, a standardized Valsalva maneuver test wherein the patients were asked in a minimum of 10 seconds to maintain an expiratory pressure greater than 30 mmHg, and a test wherein the patients’ blood samples were extracted after tilting them uprightly at a 60 degree angle without moving for 10 minutes. The data collected by the researchers were calculated for statistical analysis.Results and Recommendations The researchers stated that among the sample population of 444 patients, 402 were said to have OH. Among these 402 patients, 378 suffer from Parkinson’s disease, dementia, autonomic failure, or multiple system atrophy.
The 24 remaining patients have nonneurogenic OH derived from their lower volume. This decrease in volume may be a result of their anemia or of their number of medications (polypharmacy). Nonetheless, the patients with neurogenic OH had a lower systolic blood pressure and higher heart rate (HR). Although the study was successful with regards to their objective to identify a specific range for identifying the presence of OH in a person, the researchers have not relayed whether the range was applicable in all cases of OH or only for a limited sample only. Furthermore, the research itself lacked a detailed discussion on the patients with other disorders and its relation to OH–whether the presence of other disorders affects the chance of developing OH. In addition to this, the study was not able to associate the relevance of the age of the patients and its relationship with OH. Although it was not the primary focus of the research, it may be relevant to succeeding researches about its link and probability of developing OH.
Reference:Norcliffe-Kaufmann, L., Kaufmann, H., et al.
(2018). Orthostatic Heart Rate Changes in Patients with Autonomic Failure Caused by Neurodegenerative Synucleinopathies. Annals of neurology, 83(3), 522-531. doi: 10.1002/ana.25170