DAILY LEAD
Plasma β-hydroxybutyrate concentrations in young adult females after a high-fat meal under normoxaemia, intermittent hypoxaemia and continuous hypoxaemia: An exploratory analysis.
Observation and source date: 24 July 2026. This issue uses PubMed Date-Publication records; the matching arXiv submitted-date window returned no relevant new records.
Hypoxaemia occurs in intermittent forms, such as obstructive sleep apnoea, and in continuous forms, such as at high altitude, and is increasingly recognized as a modulator of cardiometabolic risk. Although hypoxaemia alters postprandial glucose and lipid metabolism, its effects on ketone bodies remain unclear. Using a randomized crossover design, we examined whether 6 h of normoxaemia or intermittent hypoxaemia (15 hypoxaemic cycles/h targeting ∼85% peripheral oxyhaemoglobin saturation with 100% medical-grade nitrogen) alters plasma β-hydroxybutyrate (BHB) concentrations in 12 young adult females (mean [SD]: 21 [3] years) following a high-fat meal (33% of estimated daily energy requirements; 59% of energy from fat). In a follow-up session, a subset (n = 8) completed 6 h of continuous hypoxaemia (fraction of inspired oxygen ∼12.0% in a normobaric chamber). Postprandial data were analysed using baseline-adjusted linear mixed-effects models, with Bonferroni post hoc tests. A time × condition interaction (P = 0.010) indicated that BHB concentrations at 360 min were higher during continuous hypoxaemia (0.247 mmol/L; 95% CI: 0.218-0.275) than normoxaemia (0.176 mmol/L; 95% CI: 0.153-0.200; PBonferroni = 0.029) and intermittent hypoxaemia (0.163 mmol/L; 95% CI: 0.139-0.186; PBonferroni = 0.002), representing increases of 13.0% and 14.2% in estimated marginal means, respectively. This response was accompanied by higher postprandial plasma glucose and triglyceride concentrations during continuous hypoxaemia than during normoxaemia and intermittent hypoxaemia (PBonferroni ≤ 0.002), despite similar plasma insulin and non-esterified fatty acid responses across conditions (P ≥ 0.081). These findings indicate that continuous hypoxaemia increases late postprandial plasma BHB concentrations in young adult females.
Evidence boundary: 样本很小，连续低氧随访子集仅8人；这是探索性生理结果，不能外推为饮食或睡眠呼吸疾病建议。