Obstructive sleep apnoea syndrome promotes reversal albuminuria during sleep.

INTRODUCTION: Sleep apnoea syndrome (OSAS) may induce albuminuria during sleep which could reflect one of the possible pathogenetic mechanisms regarding cardiovascular risk. MATERIALS AND METHODS: We studied 224 patients with newly diagnosed OSAS, free of any chronic disease, and any regular drug therapy. The levels of urine albumin/creatinine ratio (ACR) before (ACR-bsleep) and immediately after (ACR-asleep) a sleep study were determined. The same procedure was repeated during the first night on CPAP treatment (n = 121) and in 46 reevaluated patients, after 3 months, on CPAP therapy. Ambulatory blood pressure was monitored in 133 of the patients. RESULTS: ACR-asleep was significantly higher in patients (17.82 ± 31.10 mg/g) compared with controls (6.54 ± 6.53 mg/g, p < 0.001). The mean percent change in ACR levels between after and before sleep (%dACR) was increased by 8.82% ± 61.06 in OSAS patients and reduced by 26.87% ± 18.95 in controls (p < 0.001). During the first sleep study on CPAP, the %dACR was reduced by 21.40% ± 24.59, in contrast to the increase observed during the initial study (10.73% ± 69.93, p < 0.001). This beneficial effect of CPAP treatment was preserved in the reevaluated patients. The %dACR was +29.33% ± 57.67 in nondippers (44% of the patients) and -5.57% ± 40.81 in dippers (p < 0.001). It was negatively correlated to the percent change of systolic (rho = -0.284, p = 0.003) and diastolic (rho = -0.341, p < 0.001) blood pressure between wakefulness and sleep. Contrary to normal people, ACR is increased in OSAS patients during sleep, at least partially, related to the nondipping phenomenon observed in these patients. Following CPAP treatment, urinary albumin excretion is reduced.

Blood pressure and serum potassium levels in hypertensive patients receiving or not receiving antihypertensive treatment.

OBJECTIVE: Serum potassium has a fundamental role in blood pressure (BP) regulation, and there is evidence highlighting the importance of potassium homeostasis in hypertension. The aim of this study was to determine the relationship between serum potassium levels and office BP in untreated essential hypertensives and the effect of antihypertensive medication on serum potassium levels. SETTING AND PARTICIPANTS: In a retrospective analysis, we collected data for consecutive patients first visiting our Hypertension Clinic from 1999-2004. From this population, we first selected patients who were not taking any antihypertensive medication. Patients who had conditions that could affect potassium metabolism, such as history of arrhythmias treated with digitalis, diabetes mellitus under insulin treatment, and hypo- and hyperthyroidism, were excluded from the study. From the remaining patients, those who had impaired renal function (serum creatinine > or = 1.6 mg/dL for men and > or = 1.4 mg/dl for women) and patients with secondary forms of hypertension were also excluded. The final population consisted of 817 subjects. Multivariate linear regression analysis was applied, and models were created associating serum potassium with systolic BP, diastolic BP, mean BP, or pulse pressure. The population for the second part of the study consisted of patients first visiting our Hypertension Clinic who were on one antihypertensive agent. This second group included 757 patients, 218 of whom were on beta-blockers, 42 on diuretics, 187 on angiotensin-converting enzyme (ACE) inhibitors, 287 on calcium channel blockers (CCBs), and 28 on angiotensin receptor blockers (ARBs). RESULTS: After adjusting for age, gender, and body mass index, significant negative correlations were found between serum potassium levels and systolic BP (R = -0.093, p = 0.007), diastolic BP (R = -0.078, p = 0.03), mean BP (R = -0.122, p = 0.002), and pulse pressure (R = -0.071, p = 0.044). The levels of potassium were found to be significantly lower among patients receiving diuretics than those receiving one of the other four drug categories of antihypertensive (p < 0.05 for beta-blockers, ACE inhibitors, and CCBs; p < 0.001 for ARBs). In addition, hypokalemia was found to be significantly more prevalent in the group using diuretics than the other groups. CONCLUSIONS: The observed reverse relation between serum potassium and BP supports a close pathophysiological connection between serum potassium and essential hypertension. Moreover, diuretic therapy is a significant cause of hypokalemia and requires systematic monitoring.

Peritoneal dialysis glossary 2009.

A number of attempts to create a commonly accepted terminology regarding definitions and terms used for clinical entities, methods, problems, and materials encountered by health professionals involved in peritoneal dialysis (PD) were undertaken in the past, the last one in 1990. Later on, some relevant sporadic attempts in a number of textbooks have been made, but they did not include the whole spectrum of PD. This glossary is an attempt to address the need for a universally accepted PD terminology including the latest advances in PD connection systems and fluids.