Houtveen Jan H, van Doornen Lorenz J P
Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands. j.h.houtveen@uu/nl
Biol Psychol. 2007 Oct;76(3):239-49. doi: 10.1016/j.biopsycho.2007.08.005. Epub 2007 Aug 30.
People with medically unexplained symptoms (MUS) often have a comorbid history of stress and negative affect. Although the verbal-cognitive and (peripheral) physiological stress systems have shown a great degree of independence, at the same time it is claimed that chronic stress and negative affect can result in a disregulated physiological stress system, which may lead to MUS. Previous studies could not demonstrate a straightforward between subject relationship between MUS and stress physiology, supporting the view of independence. The aim of the current study was to further explore this relationship using an improved methodology based on ecologically valid 24-h real-life ambulatory recordings. Seventy-four participants (19 male; 55 female) with heterogeneous MUS were compared with 71 healthy controls (26 male; 45 females). Momentary experienced somatic complaints and mood, heart rate, cardiac autonomic activity, respiration and saliva cortisol were monitored using electronic diary and ambulatory registration devices. Participants with MUS reported much more momentary complaints and negative affect as compared to controls. Although MUS seemed to be associated with elevated heart rate and reduced low and very-low frequency heart period variability, these effects disappeared after controlling for differences in sports behaviour. No group differences were found for cardiac autonomic activity, respiration, end-tidal CO(2) and saliva cortisol. Our 24-h real-life ambulatory study did not support the existence of a connection between MUS and disregulated peripheral stress physiology. Future studies may instead focus on central measures to reveal potential abnormalities such as deviant central processing of visceral signals in MUS patients.
患有医学上无法解释的症状（MUS）的人通常有压力和负面影响的共病病史。尽管言语认知和（外周）生理应激系统已显示出很大程度的独立性，但同时有人认为，慢性压力和负面影响会导致生理应激系统失调，这可能会导致出现MUS。先前的研究未能证明MUS与应激生理学之间存在直接的受试者间关系，这支持了独立性的观点。本研究的目的是使用基于生态有效24小时现实生活动态记录的改进方法，进一步探索这种关系。将74名患有异质性MUS的参与者（19名男性；55名女性）与71名健康对照者（26名男性；45名女性）进行比较。使用电子日记和动态记录设备监测瞬间体验到的躯体不适和情绪、心率、心脏自主活动、呼吸和唾液皮质醇。与对照组相比，患有MUS的参与者报告的瞬间不适和负面影响要多得多。尽管MUS似乎与心率升高以及低频和极低频心动周期变异性降低有关，但在控制了运动行为差异后，这些影响消失了。在心脏自主活动、呼吸、呼气末二氧化碳和唾液皮质醇方面未发现组间差异。我们的24小时现实生活动态研究不支持MUS与外周应激生理失调之间存在联系。未来的研究可能转而关注中枢测量，以揭示潜在异常，如MUS患者内脏信号的异常中枢处理。
