Distorted symptom perception in patients with medically unexplained symptoms.

Abstract

The present study investigated differences in symptom perception between a clinical sample with medically unexplained symptoms (MUS) and a matched healthy control group. Participants (N = 58, 29 patients) were told that they would inhale different gas mixtures that might induce symptoms. Next, they went through 2 subsequent rebreathing trials consisting of a baseline (60 s room air breathing), a rebreathing phase (150 s, which gradually increased ventilation, PCO2 in the blood, and perceived dyspnea), and a recovery phase (150 s, returning to room air breathing). Breathing behavior was continuously monitored, and dyspnea was rated every 10 s. The within-subject correlations between dyspnea on the one hand and end-tidal CO2 and minute ventilation on the other were used to index the degree to which perceived dyspnea was related to specific relevant respiratory changes. The results showed that perceived symptoms were less strongly related to relevant physiological parameters in MUS patients than in healthy persons, specifically when afferent physiological input was relatively weak. This suggests a stronger role for top-down psychological processes in the symptom perception of patients with MUS.

Symptoms and the body: Taking the inferential leap

“…'false alarms'), seemingly contradicting the prediction of improved accuracy. Similarly, Van den Bergh and colleagues found significantly lower correspondence between induced respiratory changes and self-reported breathlessness in a CO 2 inhalation paradigm for non-clinical MUS reporters (Bogaerts et al, 2008) and MUS patients (Bogaerts et al, 2010b).…”

“…This effect only appeared when participants were asked to rate "symptoms" (e.g., dyspnea/breathlessness) and not when rating neutrally labelled "sensations" (e.g., breathing intensity), showing that a reduction in sensory-perceptual detail is only applied when contextual cues advance symptom-related priors (Bogaerts et al, 2005(Bogaerts et al, , 2008(Bogaerts et al, , 2010b. Less detailed sensoryperceptual processing of somatic episodes in SSD patients may also underlie the absence of a peak-end bias when evaluating previous somatic episodes (Bogaerts et al, 2012) and less specific healthrelated autobiographical memories (Walentynowicz et al, 2016).…”

Health hazard evaluation report: evaluation of indoor environmental quality in a college teaching and administrative building.

“…A symptom is any subjective sensation or perceived change in bodily function which only the individual can perceive. Research has shown that symptoms are influenced by cognitive processes [Bogaerts et al 2010]. In this evaluation there was heightened awareness by building occupants of a suspected problem in the building.…”

“…These symptoms are rarely caused by serious illness. In fact, 15%-50% of primary care visits are for what is termed "medically unexplained symptoms" [Kirmayer et al 2004;Jackson et al 2009;Bogaerts et al 2010].…”

Health hazard evaluation report: evaluation of indoor environmental quality in a natural history building.

“…We have learned from prior indoor environmental evaluations that often symptoms reported by building occupants are wide ranging, do not suggest a particular medical diagnosis, and are not readily associated with a causative agent. Symptoms are influenced by cognitive (thought) processes [Bogaerts et al 2010] and are more common when pollution or health threats are perceived, as on the seventh floor [Watson and Pennebaker 1989;Williams and Lees-Haley 1993]. Of the general population, 86%-95% have one or more common symptoms during any 2-to 4-week period.…”