Syncope and near-syncope as a multifactorial problem in geriatric inpatients: Systemic hypotension is an underrated predictor for syncope exclusively.

PURPOSE: Syncope (SC) and near-syncope (NS) are still misunderstood syndromes. Aim of study was to determine the risk factors for SC, NS, as well as for both entities (SC/NS) in geriatric inpatients reporting these events within the last year, irrespectively of the reason of admission to hospital. MATERIAL AND METHODS: The retrospective study covered 250 patients, consecutively admitted to the geriatric ward. Patients were assigned to the three models: SC and/or NS in total, n=106; isolated NS, n=72; SC with co-existing NS, if any, n=34, and compared with patients without any such events (n=144). The patients underwent a comprehensive geriatric assessment and complete clinical investigation. The binary logistic regression was applied to predict risk factors for each of the models. RESULTS: Falls were most predictive for NS model (OR 35.4; 95% CI 10.3-121.1), and systemic hypotension for SC model (OR 92.9; 95% CI 6.1-1421.0). The highest specificity (85%) and sensitivity (81%) were found for the SC/NS model, with the highest contribution by falls (OR 18.1; 95% CI, 7.6-45.2), orthostatic hypotension (OR 8.1; 95% CI, 3.5-18.5), a history of stroke or transient ischemic attack, treatment with an angiotensin receptor blocker, plasma creatinine >1.4mg/dL, negatively self-rated health, vertigo, pathology of carotid arteries, and lack of hypertension. CONCLUSIONS: Syncope and near-syncope in geriatric inpatients have multifactorial and cumulative aetiology, with blurred, frequently overlapping boundaries between them. The falls, postural hypotension, and/or brain hypoperfusion of different origin seem to be most predictive of the both events, however low systemic blood pressure was predictive for the syncope exclusively.

Kynurenine and its metabolites in Alzheimer's disease patients.

PURPOSE: The kynurenine pathway (KP) is a major route of tryptophan metabolism. Several metabolites of this pathway are proposed to be involved in the pathogenesis of Alzheimer's disease. The aim of this study was to evaluate peripheral KP in patients with Alzheimer type dementia and a detailed analysis of correlation between kynurenine (KYN), kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), anthranilic acid (AA), quinolinic acid (QUIN) and degree of neuropsychological changes in AD. MATERIAL/METHODS: The plasma concentration of tryptophan and its products degradation by kynurenine pathway were analyzed in 34 patients suffering from Alzheimer type dementia and 18 controls in similar age using high-performance liquid chromatography technique. RESULTS: In demented patients we found lower tryptophan and KYNA concentrations. There was a non-significant increase of KYN, 3-HK and AA levels, and a Marked increase of QUIN in Alzheimer's disease group. We observed positive correlations between cognitive function tests and plasma KYNA levels, and inversely correlations between these tests and QUIN levels in Alzheimer type dementia. CONCLUSIONS: Increased TRP degradation and simultaneous altered kynurenines levels were found in plasma of AD patients. It proves activation of peripheral kynurenine pathway in this type of dementia. The alterations of two main KYN metabolites: KYNA and QUIN seem to be associated with the impairment of the cognitive function in AD patients. This appears to offer Novel therapeutic opportunities, with the development of new compounds as a promising perspective for brain neuroprotection.