Isolated systolic hypertension in the young: a position paper endorsed by the European Society of Hypertension.

: Whether isolated systolic hypertension in the young (ISHY) implies a worse outcome and needs antihypertensive treatment is still a matter for dispute. ISHY is thought to have different mechanisms than systolic hypertension in the elderly. However, findings from previous studies have provided inconsistent results. From the analysis of the literature, two main lines of research and conceptualization have emerged. Simultaneous assessment of peripheral and central blood pressure led to the identification of a condition called pseudo or spurious hypertension, which was considered an innocent condition. However, an increase in pulse wave velocity has been found by some authors in about 20% of the individuals with ISHY. In addition, obesity and metabolic disturbances have often been documented to be associated with ISHY both in children and young adults. The first aspect to consider whenever evaluating a person with ISHY is the possible presence of white-coat hypertension, which has been frequently found in this condition. In addition, assessment of central blood pressure is useful for identifying ISHY patients whose central blood pressure is normal. ISHY is infrequently mentioned in the guidelines on diagnosis and treatment of hypertension. According to the 2013 European Guidelines on the management of hypertension, people with ISHY should be followed carefully, modifying risk factors by lifestyle changes and avoiding antihypertensive drugs. Only future clinical trials will elucidate if a benefit can be achieved with pharmacological treatment in some subgroups of ISHY patients with associated risk factors and/or high central blood pressure.

Index measured at an intermediate altitude to predict impending acute mountain sickness.

PURPOSE: Acute mountain sickness (AMS) is a neurological disorder that may be unpredictably experienced by subjects ascending at a high altitude. The aim of the present study was to develop a predictive index, measured at an intermediate altitude, to predict the onset of AMS at a higher altitude. METHODS: In the first part, 47 subjects were investigated and blood withdrawals were performed before ascent, at an intermediate altitude (3440 m), and after acute and chronic exposition to high altitude (Mount Everest Base Camp, 5400 m (MEBC1 and MEBC2)). Parameters independently associated to the Lake Louise scoring (LLS) system, including the self-reported and the clinical sections, and coefficients estimated from the model obtained through stepwise regression analysis were used to create a predictive index. The possibility of the index, measured after an overnight stay at intermediate altitude (Gnifetti hut, 3647 m), to predict AMS (defined as headache and LLS ≥ 4) at final altitude (Capanna Margherita, 4559 m), was then investigated in a prospective study performed on 44 subjects in the Italian Alps. RESULTS: During the expedition to MEBC, oxygen saturation, hematocrit, day of expedition, and maximum velocity of clot formation were selected as independently associated with LLS and were included in the predictive index. In the Italian Alps, subjects with a predictive index value ≥ 5.92 at an intermediate altitude had an odds ratio of 8.1 (95% confidence limits = 1.7-38.6, sensitivity = 85%, specificity = 59%) for developing AMS within 48 h of reaching high altitude. CONCLUSION: In conclusion, a predictive index combining clinical and hematological parameters measured at an intermediate step on the way to the top may provide information on impending AMS.

Continuous positive airway pressure increases haemoglobin O2 saturation after acute but not prolonged altitude exposure.

AIMS: It is unknown whether subclinical high-altitude pulmonary oedema reduces spontaneously after prolonged altitude exposure. Continuous positive airway pressure (CPAP) removes extravascular lung fluids and improves haemoglobin oxygen saturation in acute cardiogenic oedema. We evaluated the presence of pulmonary extravascular fluid increase by assessing CPAP effects on haemoglobin oxygen saturation under acute and prolonged altitude exposure. METHODS AND RESULTS: We applied 7 cm H(2)O CPAP for 30 min to healthy individuals after acute (Capanna Margherita, CM, 4559 m, 2 days permanence, and <36 h hike) and prolonged altitude exposure (Mount Everest South Base Camp, MEBC, 5350 m, 10 days permanence, and 9 days hike). At CM, CPAP reduced heart rate and systolic pulmonary artery pressure while haemoglobin oxygen saturation increased from 80% (median), 78-81 (first to third quartiles), to 91%, 84-97 (P < 0.001). After 10 days at MEBC, haemoglobin oxygen saturation spontaneously increased from 77% (74-82) to 86% (82-89) (P < 0.001) while heart rate (from 79, 64-92, to 70, 54-81; P < 0.001) and respiratory rate (from 15, 13-17, to 13, 13-15; P < 0.001) decreased. Under such conditions, these parameters were not influenced by CPAP. CONCLUSION: After ascent excessive lung fluids accumulate affecting haemoglobin oxygen saturation and, in these circumstances, CPAP is effective. Acclimatization implies spontaneous haemoglobin oxygen saturation increase and, after prolonged altitude exposure, CPAP is not associated with HbO(2)-sat increase suggesting a reduction in alveolar fluids.