Hypotensive episodes at 24-h ambulatory blood pressure monitoring predict adverse outcomes in Parkinson's disease.

PURPOSE: Neurogenic orthostatic hypotension (nOH) is a frequent nonmotor feature of Parkinson's disease (PD), associated with adverse outcomes. Recently, 24-h ambulatory blood pressure monitoring (ABPM) showed good accuracy in diagnosing nOH. This study aims at evaluating the prognostic role of ABPM-hypotensive episodes in predicting PD disability milestones and mortality and comparing it to the well-defined prognostic role of bedside nOH. METHODS: Patients with PD who underwent ABPM from January 2012 to December 2014 were retrospectively enrolled and assessed for the development of falls, fractures, dementia, bed/wheelchair confinement, hospitalization, and mortality, during an up-to-10-year follow-up. Significant ABPM-hypotensive episodes were identified when greater than or equal to two episodes of systolic BP drop ≥ 15 mmHg (compared with the average 24 h) were recorded during the awakening-to-lunch period. RESULTS: A total of 99 patients (74% male, age 64.0 ± 10.1 years, and PD duration 6.4 ± 4.0 years) were enrolled. At baseline, 38.4% of patients had ABPM-hypotensive episodes and 46.5% had bedside nOH. On Kaplan-Meier analysis, patients with ABPM-hypotensive episodes showed earlier onset of falls (p = 0.001), fractures (p = 0.004), hospitalizations (p = 0.009), bed/wheelchair confinement (p = 0.032), dementia (p = 0.001), and shorter survival (8.0 versus 9.5 years; p = 0.009). At Cox regression analysis (adjusted for age, disease duration, Charlson Comorbidity Index, and Hoehn and Yahr stage) a significant association was confirmed between ABPM-hypotensive episodes and falls [odds ratio (OR) 3.626; p = 0.001), hospitalizations (OR 2.016; p = 0.038), and dementia (OR 2.926; p = 0.008), while bedside nOH was only associated with falls (OR 2.022; p = 0.039) and dementia (OR 1.908; p = 0.048). CONCLUSIONS: The presence of at least two ABPM-hypotensive episodes independently predicted the development of falls, dementia, and hospitalization, showing a stronger prognostic value than the simple bedside assessment.

Hypotensive episodes at 24-h Ambulatory Blood Pressure Monitoring predict adverse outcomes in Parkinson's Disease.

Purpose: Neurogenic orthostatic hypotension (nOH) is a frequent non-motor feature of Parkinson's disease (PD), associated with adverse outcomes. Recently, 24-hour ambulatory BP monitoring (ABPM) has been shown to diagnose nOH with good accuracy (in the presence of at least 2 episodes of systolic BP drop ≥ 15 mmHg compared to the average 24-h). This study aims at evaluating the prognostic role of ABPM-hypotensive episodes in predicting PD disability milestones and mortality and comparing it to well-defined prognostic role of nOH. Methods: PD patients who underwent ABPM from January 2012 to December 2014 were retrospectively enrolled and assessed for the development of falls, fractures, dementia, bed/wheelchair confinement, hospitalization, mortality, during an up-to-10-year follow-up. Results: Ninety-nine patients (male 74%; age: 64.0 ± 10.1 years; PD duration: 6.4 ± 4.0 years) were enrolled. At baseline, 38.4% of patients had ABPM-hypotensive episodes and 46.5% had bedside nOH.At Kaplan-Meier analysis patients with ABPM-hypotensive episodes had an earlier onset of falls (p = 0.001), fractures (p = 0.004), hospitalizations (p = 0.009), bed/wheelchair confinement (p = 0.032), dementia (p = 0.001), and showed a shorter survival (8.0vs9.5 years; p = 0.009). At Cox regression analysis (adjusted for age, disease duration, Charlson Comorbidity Index, and H&Y stage at baseline) a significant association was confirmed between ABPM-hypotensive episodes and falls (OR:3.626; p = 0.001), hospitalizations (OR:2.016; p = 0.038), and dementia (OR:2.926; p = 0.008), while bedside nOH was only associated with falls (OR 2.022; p = 0.039) and dementia (OR:1.908; p = 0.048). Conclusion: The presence of at least two ABPM-hypotensive episodes independently predicted the development of falls, dementia, and hospitalization, showing a stronger prognostic value than the simple bedside assessment.

Cardiovascular Response to Posture Changes: Multiscale Modeling and in vivo Validation During Head-Up Tilt.

In spite of cardiovascular system (CVS) response to posture changes have been widely studied, a number of mechanisms and their interplay in regulating central blood pressure and organs perfusion upon orthostatic stress are not yet clear. We propose a novel multiscale 1D-0D mathematical model of the human CVS to investigate the effects of passive (i.e., through head-up tilt without muscular intervention) posture changes. The model includes the main short-term regulation mechanisms and is carefully validated against literature data and in vivo measures here carried out. The model is used to study the transient and steady-state response of the CVS to tilting, the effects of the tilting rate, and the differences between tilt-up and tilt-down. Passive upright tilt led to an increase of mean arterial pressure and heart rate, and a decrease of stroke volume and cardiac output, in agreement with literature data and present in vivo experiments. Pressure and flow rate waveform analysis along the arterial tree together with mechano-energetic and oxygen consumption parameters highlighted that the whole system approaches a less stressed condition at passive upright posture than supine, with a slight unbalance of the energy supply-demand ratio. The transient dynamics is not symmetric in tilt-up and tilt-down testing, and is non-linearly affected by the tilting rate, with stronger under- and overshoots of the hemodynamic parameters as the duration of tilt is reduced. By enriching the CVS response to posture changes, the present modeling approach shows promise in a number of applications, ranging from autonomic system disorders to spaceflight deconditioning.