Nocturnal pulse oxygen saturation dynamics at simulated high altitudeNarang, Benjamin J. (Avtor) Manferdelli, Giorgio (Avtor) Millet, Grégoire P. (Avtor) Debevec, Tadej (Avtor) sporthypoxiaprematuritypulse oximetrysleepThe physiological sequelae of pre-term birth might influence the responses of this population to hypoxia. Moreover, identifying variables associated with development of acute mountain sickness (AMS) remains a key practically significant area of altitude research. We investigated the effects of pre-term birth on nocturnal oxygen saturation (S$_p$o$_2$) dynamics and assessed the predictive potential of nocturnal S$_p$o$_2$-related metrics for morning AMS in 12 healthy adults with gestational age < 32 weeks (pre-term) and 12 term-born control participants. Participants spent one night at a simulated altitude of ∼4200 m (normobaric hypoxia; fraction of inspired O$_2$= 0.141), with nocturnal S$_p$o$_2$ and heart rate recorded continuously at the fingertip using pulse oximetry and with morning AMS assessed using the Lake Louise scale. Pre-term and term-born participants had similar nocturnal mean S$_p$o$_2$ (mean ± SD; 77% ± 3% vs. 77% ± 4%; P = 0.661), minimum S$_p$o$_2$ (median[IQR]; 67[4]% vs. 69[5]%; P = 0.223), relative time spent with S$_p$o$_2$ < 80% (72% ± 29% vs. 70% ± 27%; P = 0.879) and mean heart rate (79 ± 12 vs. 71 ± 7 beats/min; P = 0.053). However, the increase in S$_p$o$_2$ between the two halves of the night was blunted with prematurity (−0.12% ± 1.51% vs. 1.11% ± 0.78%; P = 0.021). Moreover, the cumulative relative desaturation-based hypoxic ‘load’ was higher with prematurity (32[26]%min/h vs. 7[25]%min/h; P = 0.039), underpinned by increased desaturation frequency (69[49] vs. 21[35] counts/h; P = 0.009). Mean S$_p$o$_2$ , minimum S$_p$o$_2$ , morning S$_p$o$_2$ and relative time spent with S$_p$o$_2$ < 80% predicted AMS incidence better than a random classifier exclusively in the pre-term group, with no other variables predictive of AMS in the two groups separately or combined. Overall, pre-term birth might alter nocturnal S$_p$o$_2$ dynamics and influence AMS prediction in severe hypoxia.20252026-05-07 11:53:57Članek v reviji182330sl