Autonomic Dysreflexia

This study looks to characterize gradients of dysfunction in the autonomic nervous system in patients with clinically diagnosed multiple sclerosis. The autonomic nervous system plays key roles in regulation of blood pressure, skin blood flow, and bladder health- all issues that individuals with multiple sclerosis typically suffer. Focusing on blood pressure regulation, the most precise metric with broad clinical applicability, the investigators will perform laboratory-based tests to probe the body's ability to generate autonomic responses. For both individuals with multiple sclerosis and uninjured controls, laboratory-based experiments will utilize multiple parallel recordings to identify how the autonomic nervous system is able to inhibit and activate signals. The investigators anticipate that those with autonomic dysfunction with multiple sclerosis will exhibit abnormalities in these precise metrics. The investigators will look to see if any substantial connections exist between different degrees of preserved autonomic function and secondary autonomic complications from multiple sclerosis. In accomplishing this, the investigators hope to give scientists important insights to how the autonomic nervous system works after multiple sclerosis and give physicians better tools to manage these secondary autonomic complications.

This study looks to characterize gradients of dysfunction in the autonomic nervous system after spinal cord injury. The autonomic nervous system plays key roles in regulation of blood pressure, skin blood flow, and bladder health- all issues that individuals with spinal cord injury typically suffer. Focusing on blood pressure regulation, the most precise metric with broad clinical applicability, the investigators will perform laboratory-based tests to probe the body's ability to generate autonomic responses. For both individuals with spinal cord injury and uninjured controls, laboratory-based experiments will utilize multiple parallel recordings to identify how the autonomic nervous system is able to inhibit and activate signals. The investigators anticipate that those with autonomic dysfunction after spinal cord injury will exhibit abnormalities in these precise metrics. The investigators will further have research participants wear a smart watch that tracks skin electrical conductance, heart rate, and skin temperature, which can all provide clues as to the degree of autonomic dysfunction someone may suffer at home. The investigators will look to see if any substantial connections exist between different degrees of preserved autonomic function and secondary autonomic complications from spinal cord injury. In accomplishing this, the investigators hope to give scientists important insights to how the autonomic nervous system works after spinal cord injury and give physicians better tools to manage these secondary autonomic complications.

The goal of this clinical trial is to learn if non-invasive spinal cord stimulation intervention improves blood pressure regulation in individuals with chronic spinal cord injury. The main questions it aims to answer are: * Can site specific spinal cord stimulation enhance blood pressure regulation? * Does this stimulation affect enzymes responsible for blood pressure regulation? Researchers will stimulate different sites of spinal cord and compare to see if site-specific stimulation provide blood pressure stability. Participants will have up to six pairs of self-adhesive conductive electrodes placed on the skin over the spinal cord (midline and/or just to the left and right of midline) as cathodes and up to six pairs of self-adhesive electrodes located symmetrically on the skin over the iliac crests, clavicles, shoulders, and/or abdominal muscles (left and right of the umbilicus) as anodes for stimulation of the spinal cord.

This project aims to evaluate the safety and efficacy of using a short-acting drug to reduce the maximal blood pressure during dangerous blood pressure spikes that happen during bowel care in individuals with spinal cord injury. the investigators will monitor the physiological effects of this drug during at-home bowel care to best understand the drug's effects in typical use.

This case-control study aims to investigate left ventricular remodeling in individuals with chronic spinal cord injury or disease (SCI/D) (≥10 years) and autonomic dysreflexia (AD) who have no prior cardiovascular history. The primary objective is to compare cardiac changes between 24 individuals with high-level SCI/D (above Th6) who have AD and 24 individuals with low-level SCI/D (below Th10) who do not have AD. A secondary objective examines how factors such as age, sex, injury duration, and physical activity are associated with cardiac remodeling. All 48 participants will undergo cardiac MRI as well as blood measurement of B-type natriuretic peptid to assess cardiac morphology and function. The findings could shed light on a potentially underestimated cardiovascular risk factor in the SCI/D population.

In patients with spinal cord injury, the investigators want to understand and understand the differences in AD prevalence and characteristics according to bladder injection rate, and to determine which factors have a greater influence between bladder expansion or injection rate.

This study is a pilot clinical trial to explore the efficacy of transcutaneous spinal cord stimulation (TCSCS) (proof-of-concept) in mitigating crucial autonomic dysfunctions that impact the health-related quality of life of individuals with spinal cord injury (SCI).

The prevalence of autonomic dysfunction and sleep disordered breathing (SDB) is increased in individuals with spinal cord injury (SCI). The loss of autonomic control results in autonomic dysreflexia (AD) and orthostatic hypotension (OH) which explains the increase in cardiovascular related mortality in these Veterans. There is no effective prophylaxis for autonomic dysfunction. The lack of prophylactic treatment for autonomic dysfunction, and no best clinical practices for SDB in SCI, are significant health concerns for Veterans with SCI. Therefore, the investigators will investigate the effectiveness of mild intermittent hypoxia (MIH) as a prophylactic for autonomic dysfunction in patients with SCI. The investigators propose that MIH targets several mechanisms associated with autonomic control and the co-morbidities associated with SDB. Specifically, exposure to MIH will promote restoration of homeostatic BP control, which would be beneficial to participation in daily activities and independence in those with SCI.