부산대학교 도서관

Objective: A blood pressure (BP) rise and sleep disturbances are known effects of high altitude exposure. Most available data have been collected at altitudes >3300m, while the possible effects of moderate altitude (MA) exposure (around 2000 m) are still poorly understood in spite of the fact that such altitude is easily reachable even by subjects suffering from cardiovascular diseases. Aim of HIGHCARE (HIGH altitude CArdiovascular REsearch)-Sestriere study was thus to evaluate the effect of exposure to an altitude of 2035m (Sestriere, Italy) on BP and sleep disturbances.(Figure is included in full-text article.)Design and Method: : 58 healthy lowlanders were evaluated both at sea level (SL,Milan, Italy) and during acute exposure to MA (2035m, barometric pressure 80% of that at SL). 46 individuals (18 male, 28 females, age 41.52 ± 12.65y) completed the study, having conventional BP measures and 24 h ambulatory BP monitoring (ABPM, validated oscillometric TM-2430 A&D device; measurements every 15 minutes during daytime and 20 minutes during nighttime) performed both at SL and at MA. During both study conditions subjects' daily life behaviour was carefully standardized, only light physical exercise being allowed.Results: During MA exposure mean 24 h systolic (S) and diastolic (D) BP significantly increased compared to SL (p < 0.005), with no difference between day and night (Figure1). This was the case also for mean daytime and nighttime SBP and DBP (respectively, p < 0.05) and for heart rate (p < 0.005) (Figure1). No statistically significant between-condition differences were found for conventional BP nor for nocturnal BP dipping, and there were no effects of age, gender or BMI. Low sleep quality was reported by 22% of individuals (sleep quality questionnaire), with no correlation between reported sleep quality and BP nocturnal dipping.Conclusions: Our data offer the first demonstration, in healthy subjects, that exposure to an easy-to-reach MA is associated with an increase in 24 h ambulatory BP. No changes were observed in conventional BP, further emphasizing the superior sensitivity of ABPM in assessing BP response to environmental challenges. Our results may have clinical implications for the protection of cardiovascular patients travelling to such altitude for either leisure or work.