Comparison of active standing test, head-up tilt test and 24-h ambulatory heart rate and blood pressure monitoring in diagnosing postural tachycardia

Protocols for the assessment of postural tachycardia differ in both type of orthostatic challenge and test duration. We therefore compared heart rate (HR) and blood pressure responses during an active standing test (AST) and a head-up tilt test (HUT) in 34 patients with orthostatic intolerance and 31 asymptomatic subjects. A subset also performed 24-h ambulatory blood pressure monitoring (ABPM). HR responses were similar between AST and HUT both in asymptomatic and in orthostatic intolerant subjects. Specificity of HR increase ≥30 bpm for orthostatic intolerance was high (above 0.85) with both AST and HUT and was similar at 3 minutes and at 9 minutes. HR changes recorded during self-performed AST (in the context of 24-h ABPM) and circadian HR difference corresponded well to changes recorded during AST in the autonomic laboratory. We conclude that AST and HUT are comparable methods for the assessment of postural tachycardia, that 3-min and 9-min tests are appropriate, and that ABPM is a useful ancillary test in the assessment of orthostatic responses

The diabetic brain and cognition

The prevalence of both Alzheimer's disease (AD) and vascular dementia (VaD) is increasing with the aging of the population. Studies from the last several years have shown that people with diabetes have an increased risk for dementia and cognitive impairment. Therefore, the authors of this consensus review tried to elaborate on the role of diabetes, especially diabetes type 2 (T2DM) in both AD and VaD. Based on the clinical and experimental work of scientists from 18 countries participating in the International Congress on Vascular Disorders and on literature search using PUBMED, it can be concluded that T2DM is a risk factor for both, AD and VaD, based on a pathology of glucose utilization. This pathology is the consequence of a disturbance of insulin-related mechanisms leading to brain insulin resistance. Although the underlying pathological mechanisms for AD and VaD are different in many aspects, the contribution of T2DM and insulin resistant brain state (IRBS) to cerebrovascular disturbances in both disorders cannot be neglected. Therefore, early diagnosis of metabolic parameters including those relevant for T2DM is required. Moreover, it is possible that therapeutic options utilized today for diabetes treatment may also have an effect on the risk for dementia. T2DM/IRBS contribute to pathological processes in AD and VaD