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Updated: Jun 17, 2026

Identification and Quantification of Deranged Metabolites in Critically Ill Patients Using NMR-Based Metabolomics
Published on: November 29, 2024
Using multilevel path analysis in analyzing 24-h ambulatory physiological recordings applied to medically unexplained
Jan H Houtveen1, Ellen L Hamaker, Lorenz J P Van Doornen
1Department of Clinical and Health Psychology, Faculty of Social Sciences, Utrecht University, 3508 TC Utrecht, The Netherlands. j.h.houtveen@uu.nl
Abstract:
A non-clinical group high on heterogeneous medically unexplained symptoms (MUS; n=97) was compared with healthy controls (n=66) on the within-subject relationships between physiological measures using multilevel path analysis. Momentary experienced somatic complaints, mood (tension and depression), cardiac autonomic activity (inter-beat intervals, pre-ejection period (PEP), and respiratory sinus arrhythmia (RSA)) and respiration (rate and partial pressure of CO(2) at the end of a normal expiration) were monitored for 24 h using electronic diary and ambulatory devices. Relationships between measures were controlled for diurnal variation and individual means. Only subtle group differences were found in the diurnal rhythm and in the within-subject relationships between physiological measures. For participants high on MUS, within-subject changes in bodily symptoms were related to changes in mood, but only marginally to the physiological measures. Results of the current path analysis confirm the subordinate role of cardiac autonomic and respiratory parameters in MUS.

