The role of physical exercise and rehabilitation in delirium.

PURPOSE: This article aims to analyze the intersections between delirium, physical exercise and rehabilitation, to better understand their interrelation and to visualize future lines of research. METHODS: In this narrative review, after an overview of brain neurophysiology and function, as common substrates to understand the relationship between delirium and physical function, we explore the scientific evidence in: (1) physical dysfunction as a risk factor for delirium; (2) physical dysfunction as a symptom of delirium and (3) functional consequences related to delirium. Later, we analyze the physical therapy as one of the main strategies in multicomponent interventions to prevent delirium, by examining intervention studies including rehabilitation, which have shown to be effective in managing delirium. Finally, we analyze how frailty, delirium and physical exercise interact with each other. RESULTS: This review confirms the close relationship between delirium and physical dysfunction; therefore, it is not surprising that physical exercise is widely used in delirium preventive strategies. Although delirium is catalogued as a neurocognitive disorder, scientific evidence shows that it is also a motor disorder, which is to be expected, since a vast body of literature already supports an interaction between motor and cognitive function. CONCLUSION: The motor component of delirium should be taken into account when designing interventions or strategies to address delirium. These interventions may have a special importance in frail older adults.

Nonlinear Dynamics of Spinning Bosonic Stars: Formation and Stability.

We perform numerical evolutions of the fully nonlinear Einstein (complex, massive) Klein-Gordon and Einstein (complex) Proca systems, to assess the formation and stability of spinning bosonic stars. In the scalar (vector) case these are known as boson (Proca) stars. Firstly, we consider the formation scenario. Starting with constraint-obeying initial data, describing a dilute, axisymmetric cloud of spinning scalar or Proca field, gravitational collapse toward a spinning star occurs, via gravitational cooling. In the scalar case the formation is transient, even for a nonperturbed initial cloud; a nonaxisymmetric instability always develops ejecting all the angular momentum from the scalar star. In the Proca case, by contrast, no instability is observed and the evolutions are compatible with the formation of a spinning Proca star. Secondly, we address the stability of an existing star, a stationary solution of the field equations. In the scalar case, a nonaxisymmetric perturbation develops, collapsing the star to a spinning black hole. No such instability is found in the Proca case, where the star survives large amplitude perturbations; moreover, some excited Proca stars decay to, and remain as, fundamental states. Our analysis suggests bosonic stars have different stability properties in the scalar (vector) case, which we tentatively relate to its toroidal (spheroidal) morphology. A parallelism with instabilities of spinning fluid stars is briefly discussed.

A Community Program of Integrated Care for Frail Older Adults: +AGIL Barcelona.

OBJECTIVES: To assess the 3-month impact on physical function of a program for community-dwelling frail older adults, based on the integration of primary care, geriatric medicine, and community resources, implemented in "real life". DESIGN: Interventional cohort study. SETTING: Primary care in Barcelona, Spain. PARTICIPANTS: Individuals aged ≥80 years (n=134), presenting at least one sign of frailty (i.e., slow gait speed, weakness, memory complaints, involuntary weight loss, poor social support). INTERVENTION: After frailty screening by the primary care team, candidates were referred to a geriatric team (geriatrician + physical therapist), who performed a comprehensive geriatric assessment and designed a tailored multidisciplinary intervention in the community, including a) multi-modal physical activity (PA) sessions, b) promotion of adherence to a Mediterranean diet c) health education and d) medication review. MEASUREMENTS: Participants were assessed based on a comprehensive geriatric assessment including physical performance (Short Physical Performance Battery -SPPB- and gait speed), at baseline and at a three month follow-up. RESULTS: A total of 112 (83.6%) participants (mean age=80.8 years, 67.9% women) were included in this research. Despite being independent in daily life, participants' physical performance was impaired (SPPB=7.5, SD=2.1, gait speed=0.71, SD=0.20 m/sec). After three months, 90.2% of participants completed ≥7.5 physical activity sessions. The mean improvements were +1.47 (SD 1.64) points (p<0.001) for SPPB, +0.08 (SD 0.13) m/sec (p<0.001) for gait speed, -5.5 (SD 12.10) sec (p<0.001) for chair stand test, and 53% (p<0.001) improved their balance. Results remained substantially unchanged after stratifying the analyses according to the severity of frailty. CONCLUSIONS: Our results suggested that a "real-world" multidisciplinary intervention, integrating primary care, geriatric care, and community services may improve physical function, a marker of frailty, within 3 months. Further studies are needed to address the long-term impact and scalability of this implementation program.