Vögele Claus, Hilbert Anja, Tuschen-Caffier Brunna
Clinical and Health Psychology Research Centre, School of Human and Life Sciences, Roehampton University, Whitelands College, Holybourne Avenue, London SW15 4JD, UK.
Physiol Behav. 2009 Aug 4;98(1-2):229-34. doi: 10.1016/j.physbeh.2009.05.018. Epub 2009 Jun 2.
Recent findings suggest sympathetic inhibition during dietary restriction as opposed to increased sympathetic activity during re-feeding. The present study investigated cardiac autonomic regulation and stress reactivity in relation to biochemical markers of dietary restriction status in women diagnosed with bulimia nervosa. We predicted that bulimic individuals (BN) with a biochemical profile indicating dietary restriction exhibit reduced cardiac sympathetic and/or increased vagal activity. We also hypothesized, that BN with a biochemical profile within a normal range (i.e. currently not dieting or malnourished) would show heart rate variability responses (HRV) and reactivity to mental stress indicating increased sympathetic activation compared with non-eating disordered controls. Seventeen female volunteers diagnosed with bulimia nervosa were categorized according to their serum profile (glucose, pre-albumin, IGF-1, TSH, leptin) into currently fasting versus non-fasting and compared with 16 non-eating disordered controls matched for age and BMI. Spectral components of HRV were calculated on heart rate data from resting and mental stress periods (standardized achievement challenge) using autoregressive analysis. Compared to non-fasting BN and controls, fasting BN showed increased vagal and decreased sympathetic modulation during both resting and recovery periods. Cardiac autonomic regulation was not impaired in response to mental challenge. No differences could be found between non-fasting BN and controls. The results confirm the notion of cardiac sympathetic inhibition and vagal dominance during dietary restriction and suggest the specificity of starvation related biochemical changes for cardiac autonomic control. The results are discussed in terms of the higher incidence in cardiac complications in these patients.
最近的研究结果表明,节食期间交感神经受到抑制,而重新进食期间交感神经活动增加。本研究调查了神经性贪食症女性患者的心脏自主神经调节和应激反应性,以及与节食状态生化指标的关系。我们预测,具有表明节食的生化特征的贪食症患者(BN),其心脏交感神经活动会降低和/或迷走神经活动会增加。我们还假设,生化特征处于正常范围内(即目前未节食或未营养不良)的BN患者,与非饮食失调对照组相比,其心率变异性反应(HRV)和对精神应激的反应性将表明交感神经激活增加。17名被诊断为神经性贪食症的女性志愿者根据其血清指标(葡萄糖、前白蛋白、胰岛素样生长因子-1、促甲状腺激素、瘦素)被分为当前禁食组和非禁食组,并与16名年龄和体重指数匹配的非饮食失调对照组进行比较。使用自回归分析,根据静息期和精神应激期(标准化成就挑战)的心率数据计算HRV的频谱成分。与非禁食的BN患者和对照组相比,禁食的BN患者在静息期和恢复期的迷走神经调节增加,交感神经调节减少。心脏自主神经调节在应对精神挑战时未受损。非禁食的BN患者和对照组之间未发现差异。结果证实了节食期间心脏交感神经抑制和迷走神经占主导地位的观点,并表明饥饿相关生化变化对心脏自主神经控制具有特异性。从这些患者心脏并发症发生率较高的角度对结果进行了讨论。