Ge Ri-Li, Stone J A, Levine B D, Babb T G
Research Center for High Altitude Medicine, Qinghai Medical College, 16 Kunlun Road, Xining, Qinghai 180001, PR China.
Respir Physiol Neurobiol. 2005 Mar;146(1):47-54. doi: 10.1016/j.resp.2004.11.009.
To investigate whether obesity is associated with alterations in respiratory chemosensitivity, we compared the ventilatory response to hypoxia (HVR) and hypercapnia (HCVR) in 9 obese men (BMI: 37.0+/-4.3 kg m(-2)) and 10 lean men (BMI: 25.8+/-4.8 kg m(-2)). HVR (DeltaVE, L min(-1) per DeltaSaO2, %) was measured by a progressive isocapnic hypoxia technique, and HCVR (DeltaVE/DeltaPETCO2, L min(-1)Torr(-1)) was measured by a progressive hypercapnic method. HCVR, was greater (p<0.001) in the obese men (2.68+/-0.78) than in the lean men (1.4+/-0.45) as was HVR (p<0.05) (1.26+/-0.65 versus 0.71+/-0.43, respectively). The difference (DeltaSaO2, 4.30+/-3.69 and 10.54+/-3.45 in the lean and obese men, respectively, p<0.01) between daytime (86+/-1 and 86+/-1%) and nighttime SaO2 (81+/-3 and 76+/-4%) at a simulated altitude of 3658 m was significantly (p<0.05) correlated with both HVR (r=0.51) and HCVR (r=0.48). These results suggest that chemosensitivity in mildly obese men is increased, not blunted. Furthermore, otherwise healthy, obese individuals have the potential for significant desaturation during sleep at high altitude possibly due to exaggerated sleep-disordered breathing.
为了研究肥胖是否与呼吸化学敏感性改变有关，我们比较了9名肥胖男性（BMI：37.0±4.3 kg/m²）和10名瘦男性（BMI：25.8±4.8 kg/m²）对低氧（HVR）和高碳酸血症（HCVR）的通气反应。通过渐进性等碳酸血症低氧技术测量HVR（每ΔSaO₂的ΔVE，L/min/%），并通过渐进性高碳酸血症方法测量HCVR（ΔVE/ΔPETCO₂，L/min/Torr⁻¹）。肥胖男性的HCVR（2.68±0.78）高于瘦男性（1.4±0.45）（p<0.001），HVR也是如此（p<0.05）（分别为1.26±0.65和0.71±0.43）。在模拟海拔3658米时，瘦男性和肥胖男性白天（86±1%和86±1%）与夜间SaO₂（81±3%和76±4%）之间的差异（ΔSaO₂，瘦男性为4.30±3.69，肥胖男性为10.54±3.45，p<0.01）与HVR（r=0.51）和HCVR（r=0.48）均显著相关（p<0.05）。这些结果表明，轻度肥胖男性的化学敏感性增加，而非减弱。此外，在其他方面健康的肥胖个体在高海拔睡眠期间可能会出现显著的血氧饱和度降低，这可能是由于睡眠呼吸紊乱加剧所致。
