Dynamic Alteration in Cerebral Total Hemoglobin Concentration Measured Using Portable Near-infrared Spectroscopy in Orthostatic Hypotension and Intolerance

A portable near infrared spectroscopy (NIRS) system was used to evaluate alterations in cerebral total hemoglobin concentration (HbT) in individuals with orthostatic hypotension (OH) and orthostatic intolerance (OI) symptoms. We enrolled 238 healthy participants (mean age, 47.9 years) and assessed the presence of OH (orthostatic blood pressure (BP) drop of systolic BP ≥ 20 mmHg or diastolic BP ≥ 10 mmHg within 3 minutes of supine-to-stand) and OI symptoms using the OH questionnaire. The participants were categorized into three groups based on the presence of OH and OI symptoms: the classic OH (OH-BP) group, symptom alone (OH-Sx) group, and control group. Random case-control matching sets (age, sex, hypertension, and diabetes mellitus) were constructed consisting of 16 OH-BP and 69 OH-Sx-control sets. We measured the time-derivative of HbT change in the prefrontal cortex during the squat-to-stand maneuver. There were no differences in demographics, baseline BP, and heart rate among the matched sets. Among the NIRS parameters, the peak-time of maximum slope variation was significantly longer in the OH-Sx and OH-BP groups than in the matched control groups during transition to the standing position after squatting. Our results suggested that OH and OI symptoms are associated with dynamic alteration in cerebral HbT.

Orthostatic Hypotension and Antiparkinsonian Drugs: A Systematic Review and Meta-analysis

Background Orthostatic hypotension (OH) is multifactorial in Parkinson’s disease (PD). Antiparkinsonian medication can contribute to OH, leading to increased risk of falls, weakness and fatigue. Methods We conducted a systematic review and meta-analysis of randomised controlled trials (RCTs) of antiparkinsonian drugs associated with OH as an adverse effect, compared to placebo. We searched EMBASE, MEDLINE and Web of Science databases until November 2020. Analysis used fixed-effects models and the GRADE tool to rate quality of evidence. Meta-analysis was performed if 3 or more studies of a drug group were available. Results Twenty-one RCTs including 3783 patients were included comparing 6 PD drug groups to placebo (MAO-B inhibitors, dopamine agonists, levodopa, COMT inhibitors, levodopa and adenosine receptor antagonists). OH was recorded as an adverse event or measurement of vital signs, without further specification on how this was defined or operationalised. Meta-analysis was performed for MAO-B inhibitors and dopamine agonists, as there were 3 or more studies for these drug groups. In this analysis, compared with placebo, neither MAO-B inhibitors or dopamine agonists were associated with increased risk of OH, (OR 2.28 [95% CI:0.81–6.46]), (OR 1.39 [95% CI:0.97–1.98]). Conclusions Most studies did not specifically report OH, or reporting of OH was limited, including how and when it was measured. Furthermore, studies specifically reporting OH included participants that were younger than typical PD populations without multimorbidity. Future trials should address this, for example,, by including individuals over the age of 75, to improve estimations of how antiparkinsonian medications affect risk of OH.

Trajectory Analysis of Orthostatic Hypotension in Parkinson’s Disease: Results From Parkinson’s Progression Markers Initiative Cohort

Background: Orthostatic hypotension (OH) in Parkinson’s disease (PD) can lead to falls, impair quality of life, and increase mortality. A trajectory analysis of OH could be useful to predict and prevent the hypotension incidence early.Methods: The longitudinal data of 660 patients with PD with disease duration up to 12 years were extracted from an integrated PD database. We used latent class mixed modeling (LCMM) to identify patient subgroups, demonstrating trajectories of changes in orthostatic blood pressure (BP) over time. The optimal number of subgroups was selected by several criteria including the Bayesian Information Criterion. Baseline information comparison between groups and backward stepwise logistic regression were conducted to define the distinguishing characteristics of these subgroups and to investigate the predictors for BP trajectory.Results: We identified three trajectories for each orthostatic change of systolic blood pressure (ΔSBP), namely, Class 1 (i.e., the increasing class) consisted of 18 participants with low ΔSBP that increased continuously during the follow-up; Class 2 (i.e., the low-stable class) consisted of 610 participants with low ΔSBP that remained low throughout the follow-up; and Class 3 (i.e., the high-stable class) consisted of 32 participants with high ΔSBP at baseline that was relatively stable throughout the follow-up. Several parameters differed among subgroups, but only male sex [odds ratio (OR) = 4.687, 95% confidence interval (CI) = 1.024–21.459], lower supine diastolic blood pressure (DBP) (OR = 0.934, 95% CI = 0.876–0.996), and lower level of total protein at baseline (OR = 0.812, 95% CI = 0.700–0.941) were significant predictors of an increasing ΔSBP trajectory.Conclusion: This study provides new information on the longitudinal development of ΔSBP in patients with PD with distinct trajectories of rapidly increasing, low-stable, and high-stable class. The parameters such as male sex, lower supine DBP, and lower total proteins help to identify the rapidly increasing class.

Cardiac Changes in Parkinson’s Disease: Lessons from Clinical and Experimental Evidence

Dysautonomia is a common non-motor symptom in Parkinson’s disease (PD). Most dysautonomic symptoms appear due to alterations in the peripheral nerves of the autonomic nervous system, including both the sympathetic and parasympathetic nervous systems. The degeneration of sympathetic nerve fibers and neurons leads to cardiovascular dysfunction, which is highly prevalent in PD patients. Cardiac alterations such as orthostatic hypotension, heart rate variability, modifications in cardiogram parameters and baroreflex dysfunction can appear in both the early and late stages of PD, worsening as the disease progresses. In PD patients it is generally found that parasympathetic activity is decreased, while sympathetic activity is increased. This situation gives rise to an imbalance of both tonicities which might, in turn, promote a higher risk of cardiac damage through tachycardia and vasoconstriction. Cardiovascular abnormalities can also appear as a side effect of PD treatment: L-DOPA can decrease blood pressure and aggravate orthostatic hypotension as a result of a negative inotropic effect on the heart. This unwanted side effect limits the therapeutic use of L-DOPA in geriatric patients with PD and can contribute to the number of hospital admissions. Therefore, it is essential to define the cardiac features related to PD for the monitorization of the heart condition in parkinsonian individuals. This information can allow the application of intervention strategies to improve the course of the disease and the proposition of new alternatives for its treatment to eliminate or reverse the motor and non-motor symptoms, especially in geriatric patients.

COVID-19-associated orthostatic hypotension syndrome: direct and indirect mechanisms of development

Background. The article presents an observation of the clinical case of orthostatic hypotension that developed after an infection caused by the SARS-CoV-2 virus. The issues of etiology, pathogenesis, diagnosis are outlined. The complexity of diagnosis at the stage of clinical observation is due to the comorbidity of possible mechanisms and the difficulty of determining the primary factor. Taking into account the study of variants of direct and indirect action of this 2019-nCoV, the description of the clinical observation of orthostatic hypotension supplements the data on the spectrum of manifestations of this disease. Aim. Analysis of the clinical case of the development of orthostatic hypotension in the post-acute period of COVID-19. Material. When conducting a literature review on the selected topic, various sources were considered. The search depth was over 7 years. For the recruitment of literature, Internet platforms UpToDate, PubMed, Medscape were used. Russian and foreign sources were studied. Methods. Anamnesis collection, objective research, specialized tests, laboratory and instrumental research methods, study of disease history, literature sources on orthostatic hypotension and the effect of COVID-19 on the autonomic nervous system. Results. The analysis of this case with the determination of the leading mechanism of orthostatic hypotension is extremely difficult. Probably, there is a combination of factors: direct and indirect effects on the nervous system at COVID-19. The direct effect is associated with the interaction of the virus with the angiotensin converting enzyme 2 receptors in the nervous system, which causes a significant increase in the concentration of bradykinin and the development of hypotension. An indirect effect is due to both increased thrombus formation with the development of PE, and autonomic dysfunction, within the framework of secondary polyneuropathy of fine fibers. Conclusion. It is likely that in the near future the number of such patients in the practice of doctors will increase, therefore, timely and correct diagnosis of these conditions, with their careful management, will be the fundamental postulates in the recovery of patients. Drawing attention to this topic will possibly expand our understanding of the spectrum of complications of COVID-19 and will greatly complement the information available today.

Orthostatic hypotension following posterior spinal fusion surgeries for spinal deformity correction in adolescents: prevalence and risk factors

Study design Retrospective case series. Objectives This study aimed to determine the prevalence and risk factors for orthostatic hypotension (OH) in adolescents undergoing posterior spinal fusion for spinal deformity correction. Methods The data of 282 consecutive adolescents who underwent posterior spinal fusion for spinal deformity correction in our center over 12 months were retrieved. Patient characteristics, including whether laminectomy or osteotomy was performed during the surgery, the occurrence of postoperative nausea and vomiting (PONV), perioperative hemoglobin albumin changes, perioperative blood transfusion, length of bed rest, willingness to ambulate, length of postoperative exercises of the lower limbs, and length of hospital stay, were collected and compared statistically between patients who did and did not develop postoperative OH. Results Of 282 patients, 197 (69.86%) developed OH postoperatively, and all cases completely resolved 5 days after the first out-of-bed exercises. Significant differences in the incidence of PONV, the willingness to ambulate and the length of postoperative exercises of the lower limbs were observed. The mean length of hospital stay of the patients with OH was longer than that of the patients without OH. Conclusion Our study suggests that temporary OH is a common manifestation following posterior spinal fusion for spinal deformity correction in adolescents. Postoperative OH may increase the length of hospital stay in these patients. Patients with PONV, who are not willing to ambulate and who perform postoperative lower limb exercises for a shorter time are more likely to have OH.