Stagnation Syndrome: Relevance of the Multilayers of Illness Experiences in Chinese Medicine to the Understanding of Functional Somatic Syndrome
Similarly, FSS's high comorbidity with mental disorder has also been observed in traditional Chinese medicine (TCM). In a study we conducted to investigate the point prevalence of major depression among patients diagnosed as having stagnation syndrome, an internal illness in TCM, the results showed that the comorbidity of stagnation syndrome with major depression was alarmingly high. Specifically, more than one quarter (26.5%) of the stagnation syndrome patients met the DSM-V diagnostic criteria for major depression. More than half (53%) of the patients experienced clinical significant depression symptoms, comparable to the rate reported among patients with somatic symptoms disorder (59.1%) (3). Stagnation syndrome, with a high point prevalent rate of 6.2% among Chinese adults, can be understood as an FSS in the language of Western medicine (4). It has long been regarded as the TCM counterpart of major depression in Western medicine because of its similarity to depression, particularly somatized depression, in terms of clinical presentations (5), such as sleeping problems, fatigue, headache, gastrointestinal problems, and emotional restlessness (6).
FSSs pose major challenges to medical practitioners and researchers. Current conventional medical therapy for FSS is only mildly effective, and the use of medical resources by FSS patients is disproportionally costly (1). The question of how to understand the FSS better is therefore of clinical significance.
A recent special section of Psychosomatic Medicine addressed new developments in somatic symptom disorders and FSS, including an important article by Van den Houte and colleagues (7) examining cognitive processes of somatosensory perception. They observed that compared with healthy controls, patients with fibromyalgia and/or chronic fatigue syndrome displayed inflated ratings of somatic symptoms in the context of negative affective states produced by negative pictures. Moreover, the magnitude of increases in symptoms after negative pictures was mediated by patients' weaker ability to identify their feelings, whereas trait negative affect did not play a mediating role. These results are consistent with our understanding of stagnation syndrome as an FSS. Based on the mind-body holistic paradigm of TCM, the etiology and maintenance of stagnation syndrome are conceptualized as a continuous interplay of physical discomforts with emotional imbalance (4). It is the presence of habitual emotion inhibition, that is, the proclivity of not identifying with feelings, rather than negative affect or depressed mood that distinguishes individuals with stagnation syndrome from healthy persons (5).
Although the sensory perception of somatic symptoms might determine the immediate unpleasantness among FSS patients, it might not fully explain their deteriorating functional outcomes. In our study on the wellness of 117 patients with stagnation syndrome, we found these patients characterized by significantly heightened somatic symptoms and debilitating functioning compared with the general population (see Table 1). It seems reasonable to postulate that these patients' unfavorable functional outcomes result from the challenges related to having somatic symptoms. To test this hypothesis, we examined the mediation effects of physical distress on daily functioning, and we found no such effect. This suggests that patients' daily functioning is not disrupted because of the elevated physical distress but other elements, despite the fact that stagnation syndrome presents itself primarily in terms of pronounced physical discomforts.
Perhaps, for functional outcomes, what matters most might not be how patients perceive the somatic symptoms but how they interpret these symptoms and the illness experiences.